,,science ,,and ,,culture ,,and ,,other ,,essays ,illustration ,,science ,,and ,,culture ,,and ,,other ,,essays ,,by ,,thomas ,,henry ,,huxley1 ,,ll4,d41 ,f4,r4,s4 ,london ,,macmillan ,,and ,,co4 ,,and ,,new ,,york #ahhh ,all rights reserved ,first ,edition printed #ahha ,reprinted #ahhb1 #ahhh4 ,,preface4 ,the ,addresses1 ,lectures1 and ,essays gathered together in this volume have appeared at intervals during the past seven years1 and ,i can give no better reason for republishing them in their present form1 than the fact that three earlier collections of a similar nature have been received with favour1 and1 indeed1 have not yet ceased to be in request4 ,i beg leave to offer my best thanks to the ,editors and ,publishers of the various publications in which these pieces have appeared1 for their kindly accorded permission to reprint them4 ,,london4 ,october #ahha4 ,,contents4 ,i4 ,,science ,,and ,,culture4 ,an ,address delivered at the ,opening of ,sir ,josiah ,mason's ,science ,college1 at ,birmingham1 on the #ast of ,october #ahhj ,pages #a to #bc ,,ii4 ,,universities3 ,,actual ,,and ,,ideal4 ,the ,inaugural ,address of the ,lord ,rector of the ,university of ,aberdeen1 #bgth ,february #ahgd4--;,contemporary ,review1 #ahgd #bd to #fd ,,iii4 ,,technical ,,education4 ,an ,address delivered to the ,working ,men's ,club and ,institute1 #ast ,december #ahgg4--,nineteenth ,century1 #ahgh #fe to #he ,,iv4 ,,elementary ,,instruction ,,in ,,physiology4 ,read at the ,meeting of the ,domestic ,economy ,congress at ,birmingham1 #ahgg #hf to #ic ,v4 ,,joseph ,,priestley4 ,an ,address delivered on the occasion of the ,presentation of a ,statue of ,priestley to the ,town of ,birmingham1 on the #ast of ,august #ahgd4--,macmillan's ,magazine1 #ahgd #id to #abg ,,vi4 ,,on ,,the ,,method ,,of ,,zadig4 ,a ,lecture delivered at the ,working ,men's ,college1 ,great ,ormond ,street1 #ahhj4--,nineteenth ,century1 #ahhj #abh to #adh ,,vii4 ,,on ,,the ,,border ,,territory ,,between ,,the ,,animal ,,and ,,the ,,vegetable ,,kingdoms4 ,an ,evening ,lecture at the ,royal ,institution1 ,friday1 ,january #bh1 #ahgf4--,macmillan's ,magazine1 #ahgd #adi to #agi ,,viii4 ,,on ,,certain ,,errors ,,respecting ,,the ,,structure ,,of ,,the ,,heart ,,attributed ,,to ,,aristotle4 ,nature1 #fth ,november #ahgi #ahj to #aih ,,ix4 ,,on ,,the ,,hypothesis ,,that ,,animals ,,are ,,automata1 ,,and ,,its ,,history4 ,an ,address delivered at the ,meeting of the ,british ,association for the ,advancement of ,science1 at ,belfast1 #ahgd4--;,fortnightly ,review1 #ahgd #aii to #bde ,x4 ,,on ,,sensation ,,and ,,the ,,unity ,,of ,,structure ,,of ,,the ,,sensiferous ,,organs4 ,an ,evening ,lecture at the ,royal ,institution1 ,friday1 ,march #g1 #ahgi4--,nineteenth ,century1 #ahgi #bdf to #bgc ,,xi4 ,,evolution ,,in ,,biology4 ,the ,encyclopdia ,britannica1 ,ninth ,edition1 vol4 viii4 #ahgh #bgd to #cji ,,xii4 ,,the ,,coming ,,of ,,age ,,of 8,,the ,,origin ,,of ,,species40 ,an evening ,lecture at the ,royal ,institution1 ,friday1 #ith ,april #ahhj4--,nature1 #ahhj #caj to #cbd ,,xiii4 ,,the ,,connection ,,of ,,the ,,biological ,,sciences ,,with ,,medicine4 ,an ,address delivered at the ,meeting of the ,international ,medical ,congress in ,london1 #ith ,august #ahha #cbe to #cdi ,i4 ,,science ,,and ,,culture4 ,six years ago1 as some of my present hearers may remember1 ,i had the privilege of addressing a large assemblage of the inhabitants of this city1 who had gathered together to do honour to the memory of their famous townsman1 ,joseph ,priestley2#a and1 if any satisfaction attaches to posthumous glory1 we may hope that the manes of the burnt-out philosopher were then finally appeased4 ,no man1 however1 who is endowed with a fair share of common sense1 and not more than a fair share of vanity1 will identify either contemporary or posthumous fame with the highest good2 and ,priestley's life leaves no doubt that he1 at any rate1 set a much higher value upon the advancement of knowledge1 and the promotion of that freedom of thought which is at once the cause and the consequence of intellectual progress4 ,hence ,i am disposed to think that1 if ,priestley could be amongst us to-day1 the occasion of our meeting would afford him even greater pleasure than the proceedings which celebrated the centenary of his chief discovery4 ,the kindly heart would be moved1 the high sense of social duty would be satisfied1 by the spectacle of well-earned wealth1 neither squandered in tawdry luxury and vainglorious show1 nor scattered with the careless charity which blesses neither him that gives nor him that takes1 but expended in the execution of a well-considered plan for the aid of present and future generations of those who are willing to help themselves4 ,we shall all be of one mind thus far4 ,but it is needful to share ,priestley's keen interest in physical science2 and to have learned1 as he had learned1 the value of scientific training in fields of inquiry apparently far remote from physical science2 in order to appreciate1 as he would have appreciated1 the value of the noble gift which ,sir ,josiah ,mason has bestowed upon the inhabitants of the ,midland district4 ,for us children of the nineteenth century1 however1 the establishment of a college under the conditions of ,sir ,josiah ,mason's ,trust1 has a significance apart from any which it could have possessed a hundred years ago4 ,it appears to be an indication that we are reaching the crisis of the battle1 or rather of the long series of battles1 which have been fought over education in a campaign which began long before ,priestley's time1 and will probably not be finished just yet4 ,in the last century1 the combatants were the champions of ancient literature1 on the one side1 and those of modern literature on the other2 but1 some thirty years#b ago1 the contest became complicated by the appearance of a third army1 ranged round the banner of ,physical ,science4 ,i am not aware that any one has authority to speak in the name of this new host4 ,for it must be admitted to be somewhat of a guerilla force1 composed largely of irregulars1 each of whom fights pretty much for his own hand4 ,but the impressions of a full private1 who has seen a good deal of service in the ranks1 respecting the present position of affairs and the conditions of a permanent peace1 may not be devoid of interest2 and ,i do not know that ,i could make a better use of the present opportunity than by laying them before you4 ,from the time that the first suggestion to introduce physical science into ordinary education was timidly whispered1 until now1 the advocates of scientific education have met with opposition of two kinds4 ,on the one hand1 they have been pooh-poohed by the men of business who pride themselves on being the representatives of practicality2 while1 on the other hand1 they have been excommunicated by the classical scholars1 in their capacity of ,levites in charge of the ark of culture and monopolists of liberal education4 ,the practical men believed that the idol whom they worship--rule of thumb--has been the source of the past prosperity1 and will suffice for the future welfare of the arts and manufactures4 ,they were of opinion that science is speculative rubbish2 that theory and practice have nothing to do with one another2 and that the scientific habit of mind is an impediment1 rather than an aid1 in the conduct of ordinary affairs4 ,i have used the past tense in speaking of the practical men--for although they were very formidable thirty years ago1 ,i am not sure that the pure species has not been extirpated4 ,in fact1 so far as mere argument goes1 they have been subjected to such a feu d'enfer that it is a miracle if any have escaped4 ,but ,i have remarked that your typical practical man has an unexpected resemblance to one of ,milton's angels4 ,his spiritual wounds1 such as are inflicted by logical weapons1 may be as deep as a well and as wide as a church door1 but beyond shedding a few drops of ichor1 celestial or otherwise1 he is no whit the worse4 ,so1 if any of these opponents be left1 ,i will not waste time in vain repetition of the demonstrative evidence of the practical value of science2 but knowing that a parable will sometimes penetrate where syllogisms fail to effect an entrance1 ,i will offer a story for their consideration4 ,once upon a time1 a boy1 with nothing to depend upon but his own vigorous nature1 was thrown into the thick of the struggle for existence in the midst of a great manufacturing population4 ,he seems to have had a hard fight1 inasmuch as1 by the time he was thirty years of age1 his total disposable funds amounted to twenty pounds4 ,nevertheless1 middle life found him giving proof of his comprehension of the practical problems he had been roughly called upon to solve1 by a career of remarkable prosperity4 ,finally1 having reached old age with its well-earned surroundings of 8honour1 troops of friends10 the hero of my story bethought himself of those who were making a like start in life1 and how he could stretch out a helping hand to them4 ,after long and anxious reflection this successful practical man of business could devise nothing better than to provide them with the means of obtaining 8sound1 extensive1 and practical scientific knowledge40 ,and he devoted a large part of his wealth and five years of incessant work to this end4 ,i need not point the moral of a tale which1 as the solid and spacious fabric of the ,scientific ,college assures us1 is no fable1 nor can anything which ,i could say intensify the force of this practical answer to practical objections4 ,we may take it for granted then1 that1 in the opinion of those best qualified to judge1 the diffusion of thorough scientific education is an absolutely essential condition of industrial progress2 and that the ,college which has been opened to-day will confer an inestimable boon upon those whose livelihood is to be gained by the practice of the arts and manufactures of the district4 ,the only question worth discussion is1 whether the conditions1 under which the work of the ,college is to be carried out1 are such as to give it the best possible chance of achieving permanent success4 ,sir ,josiah ,mason1 without doubt most wisely1 has left very large freedom of action to the trustees1 to whom he proposes ultimately to commit the administration of the ,college1 so that they may be able to adjust its arrangements in accordance with the changing conditions of the future4 ,but1 with respect to three points1 he has laid most explicit injunctions upon both administrators and teachers4 ,party politics are forbidden to enter into the minds of either1 so far as the work of the ,college is concerned2 theology is as sternly banished from its precincts2 and finally1 it is especially declared that the ,college shall make no provision for 8mere literary instruction and education40 ,it does not concern me at present to dwell upon the first two injunctions any longer than may be needful to express my full conviction of their wisdom4 ,but the third prohibition brings us face to face with those other opponents of scientific education1 who are by no means in the moribund condition of the practical man1 but alive1 alert1 and formidable4 ,it is not impossible that we shall hear this express exclusion of 8literary instruction and education0 from a ,college which1 nevertheless1 professes to give a high and efficient education1 sharply criticised4 ,certainly the time was that the ,levites of culture would have sounded their trumpets against its walls as against an educational ,jericho4 ,how often have we not been told that the study of physical science is incompetent to confer culture2 that it touches none of the higher problems of life2 and1 what is worse1 that the continual devotion to scientific studies tends to generate a narrow and bigoted belief in the applicability of scientific methods to the search after truth of all kinds4 ,how frequently one has reason to observe that no reply to a troublesome argument tells so well as calling its author a 8mere scientific specialist40 ,and1 as ,i am afraid it is not permissible to speak of this form of opposition to scientific education in the past tense2 may we not expect to be told that this1 not only omission1 but prohibition1 of 8mere literary instruction and education0 is a patent example of scientific narrow-mindedness8 ,i am not acquainted with ,sir ,josiah ,mason's reasons for the action which he has taken2 but if1 as ,i apprehend is the case1 he refers to the ordinary classical course of our schools and universities by the name of 8mere literary instruction and education10 ,i venture to offer sundry reasons of my own in support of that action4 ,for ,i hold very strongly by two convictions--,the first is1 that neither the discipline nor the subject-matter of classical education is of such direct value to the student of physical science as to justify the expenditure of valuable time upon either2 and the second is1 that for the purpose of attaining real culture1 an exclusively scientific education is at least as effectual as an exclusively literary education4 ,i need hardly point out to you that these opinions1 especially the latter1 are diametrically opposed to those of the great majority of educated ,englishmen1 influenced as they are by school and university traditions4 ,in their belief1 culture is obtainable only by a liberal education2 and a liberal education is synonymous1 not merely with education and instruction in literature1 but in one particular form of literature1 namely1 that of ,greek and ,roman antiquity4 ,they hold that the man who has learned ,latin and ,greek1 however little1 is educated2 while he who is versed in other branches of knowledge1 however deeply1 is a more or less respectable specialist1 not admissible into the cultured caste4 ,the stamp of the educated man1 the ,university degree1 is not for him4 ,i am too well acquainted with the generous catholicity of spirit1 the true sympathy with scientific thought1 which pervades the writings of our chief apostle of culture to identify him with these opinions2 and yet one may cull from one and another of those epistles to the ,philistines1 which so much delight all who do not answer to that name1 sentences which lend them some support4 ,mr4 ,arnold tells us that the meaning of culture is 8to know the best that has been thought and said in the world40 ,it is the criticism of life contained in literature4 ,that criticism regards 8,europe as being1 for intellectual and spiritual purposes1 one great confederation1 bound to a joint action and working to a common result2 and whose members have1 for their common outfit1 a knowledge of ,greek1 ,roman1 and ,eastern antiquity1 and of one another4 ,special1 local1 and temporary advantages being put out of account1 that modern nation will in the intellectual and spiritual sphere make most progress1 which most thoroughly carries out this programme4 ,and what is that but saying that we too1 all of us1 as individuals1 the more thoroughly we carry it out1 shall make the more progress80#c ,we have here to deal with two distinct propositions4 ,the first1 that a criticism of life is the essence of culture2 the second1 that literature contains the materials which suffice for the construction of such a criticism4 ,i think that we must all assent to the first proposition4 ,for culture certainly means something quite different from learning or technical skill4 ,it implies the possession of an ideal1 and the habit of critically estimating the value of things by comparison with a theoretic standard4 ,perfect culture should supply a complete theory of life1 based upon a clear knowledge alike of its possibilities and of its limitations4 ,but we may agree to all this1 and yet strongly dissent from the assumption that literature alone is competent to supply this knowledge4 ,after having learnt all that ,greek1 ,roman1 and ,eastern antiquity have thought and said1 and all that modern literatures have to tell us1 it is not self-evident that we have laid a sufficiently broad and deep foundation for that criticism of life which constitutes culture4 ,indeed1 to any one acquainted with the scope of physical science1 it is not at all evident4 ,considering progress only in the 8intellectual and spiritual sphere10 ,i find myself wholly unable to admit that either nations or individuals will really advance1 if their common outfit draws nothing from the stores of physical science4 ,i should say that an army1 without weapons of precision and with no particular base of operations1 might more hopefully enter upon a campaign on the ,rhine1 than a man1 devoid of a knowledge of what physical science has done in the last century1 upon a criticism of life4 ,when a biologist meets with an anomaly1 he instinctively turns to the study of development to clear it up4 ,the rationale of contradictory opinions may with equal confidence be sought in history4 ,it is1 happily1 no new thing that ,englishmen should employ their wealth in building and endowing institutions for educational purposes4 ,but1 five or six hundred years ago1 deeds of foundation expressed or implied conditions as nearly as possible contrary to those which have been thought expedient by ,sir ,josiah ,mason4 ,that is to say1 physical science was practically ignored1 while a certain literary training was enjoined as a means to the acquirement of knowledge which was essentially theological4 ,the reason of this singular contradiction between the actions of men alike animated by a strong and disinterested desire to promote the welfare of their fellows1 is easily discovered4 ,at that time1 in fact1 if any one desired knowledge beyond such as could be obtained by his own observation1 or by common conversation1 his first necessity was to learn the ,latin language1 inasmuch as all the higher knowledge of the western world was contained in works written in that language4 ,hence1 ,latin grammar1 with logic and rhetoric1 studied through ,latin1 were the fundamentals of education4 ,with respect to the substance of the knowledge imparted through this channel1 the ,jewish and ,christian ,scriptures1 as interpreted and supplemented by the ,romish ,church1 were held to contain a complete and infallibly true body of information4 ,theological dicta were1 to the thinkers of those days1 that which the axioms and definitions of ,euclid are to the geometers of these4 ,the business of the philosophers of the middle ages was to deduce from the data furnished by the theologians1 conclusions in accordance with ecclesiastical decrees4 ,they were allowed the high privilege of showing1 by logical process1 how and why that which the ,church said was true1 must be true4 ,and if their demonstrations fell short of or exceeded this limit1 the ,church was maternally ready to check their aberrations1 if need be1 by the help of the secular arm4 ,between the two1 our ancestors were furnished with a compact and complete criticism of life4 ,they were told how the world began and how it would end2 they learned that all material existence was but a base and insignificant blot upon the fair face of the spiritual world1 and that nature was1 to all intents and purposes1 the playground of the devil2 they learned that the earth is the centre of the visible universe1 and that man is the cynosure of things terrestrial2 and more especially was it inculcated that the course of nature had no fixed order1 but that it could be1 and constantly was1 altered by the agency of innumerable spiritual beings1 good and bad1 according as they were moved by the deeds and prayers of men4 ,the sum and substance of the whole doctrine was to produce the conviction that the only thing really worth knowing in this world was how to secure that place in a better which1 under certain conditions1 the ,church promised4 ,our ancestors had a living belief in this theory of life1 and acted upon it in their dealings with education1 as in all other matters4 ,culture meant saintliness--after the fashion of the saints of those days2 the education that led to it was1 of necessity1 theological2 and the way to theology lay through ,latin4 ,that the study of nature--further than was requisite for the satisfaction of everyday wants--should have any bearing on human life was far from the thoughts of men thus trained4 ,indeed1 as nature had been cursed for man's sake1 it was an obvious conclusion that those who meddled with nature were likely to come into pretty close contact with ,satan4 ,and1 if any born scientific investigator followed his instincts1 he might safely reckon upon earning the reputation1 and probably upon suffering the fate1 of a sorcerer4 ,had the western world been left to itself in ,chinese isolation1 there is no saying how long this state of things might have endured4 ,but1 happily1 it was not left to itself4 ,even earlier than the thirteenth century1 the development of ,moorish civilisation in ,spain and the great movement of the ,crusades had introduced the leaven which1 from that day to this1 has never ceased to work4 ,at first1 through the intermediation of ,arabic translations1 afterwards1 by the study of the originals1 the western nations of ,europe became acquainted with the writings of the ancient philosophers and poets1 and1 in time1 with the whole of the vast literature of antiquity4 ,whatever there was of high intellectual aspiration or dominant capacity in ,italy1 ,france1 ,germany1 and ,england1 spent itself for centuries in taking possession of the rich inheritance left by the dead civilisations of ,greece and ,rome4 ,marvellously aided by the invention of printing1 classical learning spread and flourished4 ,those who possessed it prided themselves on having attained the highest culture then within the reach of mankind4 ,and justly4 ,for1 saving ,dante on his solitary pinnacle1 there was no figure in modern literature at the time of the ,renascence to compare with the men of antiquity2 there was no art to compete with their sculpture2 there was no physical science but that which ,greece had created4 ,above all1 there was no other example of perfect intellectual freedom--of the unhesitating acceptance of reason as the sole guide to truth and the supreme arbiter of conduct4 ,the new learning necessarily soon exerted a profound influence upon education4 ,the language of the monks and schoolmen seemed little better than gibberish to scholars fresh from ,virgil and ,cicero1 and the study of ,latin was placed upon a new foundation4 ,moreover1 ,latin itself ceased to afford the sole key to knowledge4 ,the student who sought the highest thought of antiquity1 found only a second-hand reflection of it in ,roman literature1 and turned his face to the full light of the ,greeks4 ,and after a battle1 not altogether dissimilar to that which is at present being fought over the teaching of physical science1 the study of ,greek was recognised as an essential element of all higher education4 ,thus the ,humanists1 as they were called1 won the day2 and the great reform which they effected was of incalculable service to mankind4 ,but the ,nemesis of all reformers is finality2 and the reformers of education1 like those of religion1 fell into the profound1 however common1 error of mistaking the beginning for the end of the work of reformation4 ,the representatives of the ,humanists1 in the nineteenth century1 take their stand upon classical education as the sole avenue to culture1 as firmly as if we were still in the age of ,renascence4 ,yet1 surely1 the present intellectual relations of the modern and the ancient worlds are profoundly different from those which obtained three centuries ago4 ,leaving aside the existence of a great and characteristically modern literature1 of modern painting1 and1 especially1 of modern music1 there is one feature of the present state of the civilised world which separates it more widely from the ,renascence1 than the ,renascence was separated from the middle ages4 ,this distinctive character of our own times lies in the vast and constantly increasing part which is played by natural knowledge4 ,not only is our daily life shaped by it1 not only does the prosperity of millions of men depend upon it1 but our whole theory of life has long been influenced1 consciously or unconsciously1 by the general conceptions of the universe1 which have been forced upon us by physical science4 ,in fact1 the most elementary acquaintance with the results of scientific investigation shows us that they offer a broad and striking contradiction to the opinions so implicitly credited and taught in the middle ages4 ,the notions of the beginning and the end of the world entertained by our forefathers are no longer credible4 ,it is very certain that the earth is not the chief body in the material universe1 and that the world is not subordinated to man's use4 ,it is even more certain that nature is the expression of a definite order with which nothing interferes1 and that the chief business of mankind is to learn that order and govern themselves accordingly4 ,moreover this scientific 8criticism of life0 presents itself to us with different credentials from any other4 ,it appeals not to authority1 nor to what anybody may have thought or said1 but to nature4 ,it admits that all our interpretations of natural fact are more or less imperfect and symbolic1 and bids the learner seek for truth not among words but among things4 ,it warns us that the assertion which outstrips evidence is not only a blunder but a crime4 ,the purely classical education advocated by the representatives of the ,humanists in our day1 gives no inkling of all this4 ,a man may be a better scholar than ,erasmus1 and know no more of the chief causes of the present intellectual fermentation than ,erasmus did4 ,scholarly and pious persons1 worthy of all respect1 favour us with allocutions upon the sadness of the antagonism of science to their medival way of thinking1 which betray an ignorance of the first principles of scientific investigation1 an incapacity for understanding what a man of science means by veracity1 and an unconsciousness of the weight of established scientific truths1 which is almost comical4 ,there is no great force in the tu quoque argument1 or else the advocates of scientific education might fairly enough retort upon the modern ,humanists that they may be learned specialists1 but that they possess no such sound foundation for a criticism of life as deserves the name of culture4 ,and1 indeed1 if we were disposed to be cruel1 we might urge that the ,humanists have brought this reproach upon themselves1 not because they are too full of the spirit of the ancient ,greek1 but because they lack it4 ,the period of the ,renascence is commonly called that of the 8,revival of ,letters10 as if the influences then brought to bear upon the mind of ,western ,europe had been wholly exhausted in the field of literature4 ,i think it is very commonly forgotten that the revival of science1 effected by the same agency1 although less conspicuous1 was not less momentous4 ,in fact1 the few and scattered students of nature of that day picked up the clue to her secrets exactly as it fell from the hands of the ,greeks a thousand years before4 ,the foundations of mathematics were so well laid by them1 that our children learn their geometry from a book written for the schools of ,alexandria two thousand years ago4 ,modern astronomy is the natural continuation and development of the work of ,hipparchus and of ,ptolemy2 modern physics of that of ,democritus and of ,archimedes2 it was long before modern biological science outgrew the knowledge bequeathed to us by ,aristotle1 by ,theophrastus1 and by ,galen4 ,we cannot know all the best thoughts and sayings of the ,greeks unless we know what they thought about natural phenomena4 ,we cannot fully apprehend their criticism of life unless we understand the extent to which that criticism was affected by scientific conceptions4 ,we falsely pretend to be the inheritors of their culture1 unless we are penetrated1 as the best minds among them were1 with an unhesitating faith that the free employment of reason1 in accordance with scientific method1 is the sole method of reaching truth4 ,thus ,i venture to think that the pretensions of our modern ,humanists to the possession of the monopoly of culture and to the exclusive inheritance of the spirit of antiquity must be abated1 if not abandoned4 ,but ,i should be very sorry that anything ,i have said should be taken to imply a desire on my part to depreciate the value of classical education1 as it might be and as it sometimes is4 ,the native capacities of mankind vary no less than their opportunities2 and while culture is one1 the road by which one man may best reach it is widely different from that which is most advantageous to another4 ,again1 while scientific education is yet inchoate and tentative1 classical education is thoroughly well organised upon the practical experience of generations of teachers4 ,so that1 given ample time for learning and destination for ordinary life1 or for a literary career1 ,i do not think that a young ,englishman in search of culture can do better than follow the course usually marked out for him1 supplementing its deficiencies by his own efforts4 ,but for those who mean to make science their serious occupation2 or who intend to follow the profession of medicine2 or who have to enter early upon the business of life2 for all these1 in my opinion1 classical education is a mistake2 and it is for this reason that ,i am glad to see 8mere literary education and instruction0 shut out from the curriculum of ,sir ,josiah ,mason's ,college1 seeing that its inclusion would probably lead to the introduction of the ordinary smattering of ,latin and ,greek4 ,nevertheless1 ,i am the last person to question the importance of genuine literary education1 or to suppose that intellectual culture can be complete without it4 ,an exclusively scientific training will bring about a mental twist as surely as an exclusively literary training4 ,the value of the cargo does not compensate for a ship's being out of trim2 and ,i should be very sorry to think that the ,scientific ,college would turn out none but lop-sided men4 ,there is no need1 however1 that such a catastrophe should happen4 ,instruction in ,english1 ,french1 and ,german is provided1 and thus the three greatest literatures of the modern world are made accessible to the student4 ,french and ,german1 and especially the latter language1 are absolutely indispensable to those who desire full knowledge in any department of science4 ,but even supposing that the knowledge of these languages acquired is not more than sufficient for purely scientific purposes1 every ,englishman has1 in his native tongue1 an almost perfect instrument of literary expression2 and1 in his own literature1 models of every kind of literary excellence4 ,if an ,englishman cannot get literary culture out of his ,bible1 his ,shakspeare1 his ,milton1 neither1 in my belief1 will the profoundest study of ,homer and ,sophocles1 ,virgil and ,horace1 give it to him4 ,thus1 since the constitution of the ,college makes sufficient provision for literary as well as for scientific education1 and since artistic instruction is also contemplated1 it seems to me that a fairly complete culture is offered to all who are willing to take advantage of it4 ,but ,i am not sure that at this point the 8practical0 man1 scotched but not slain1 may ask what all this talk about culture has to do with an ,institution1 the object of which is defined to be 8to promote the prosperity of the manufactures and the industry of the country40 ,he may suggest that what is wanted for this end is not culture1 nor even a purely scientific discipline1 but simply a knowledge of applied science4 ,i often wish that this phrase1 8applied science10 had never been invented4 ,for it suggests that there is a sort of scientific knowledge of direct practical use1 which can be studied apart from another sort of scientific knowledge1 which is of no practical utility1 and which is termed 8pure science40 ,but there is no more complete fallacy than this4 ,what people call applied science is nothing but the application of pure science to particular classes of problems4 ,it consists of deductions from those general principles1 established by reasoning and observation1 which constitute pure science4 ,no one can safely make these deductions until he has a firm grasp of the principles2 and he can obtain that grasp only by personal experience of the operations of observation and of reasoning on which they are founded4 ,almost all the processes employed in the arts and manufactures fall within the range either of physics or of chemistry4 ,in order to improve them1 one must thoroughly understand them2 and no one has a chance of really understanding them1 unless he has obtained that mastery of principles and that habit of dealing with facts1 which is given by long-continued and well-directed purely scientific training in the physical and the chemical laboratory4 ,so that there really is no question as to the necessity of purely scientific discipline1 even if the work of the ,college were limited by the narrowest interpretation of its stated aims4 ,and1 as to the desirableness of a wider culture than that yielded by science alone1 it is to be recollected that the improvement of manufacturing processes is only one of the conditions which contribute to the prosperity of industry4 ,industry is a means and not an end2 and mankind work only to get something which they want4 ,what that something is depends partly on their innate1 and partly on their acquired1 desires4 ,if the wealth resulting from prosperous industry is to be spent upon the gratification of unworthy desires1 if the increasing perfection of manufacturing processes is to be accompanied by an increasing debasement of those who carry them on1 ,i do not see the good of industry and prosperity4 ,now it is perfectly true that men's views of what is desirable depend upon their characters2 and that the innate proclivities to which we give that name are not touched by any amount of instruction4 ,but it does not follow that even mere intellectual education may not1 to an indefinite extent1 modify the practical manifestation of the characters of men in their actions1 by supplying them with motives unknown to the ignorant4 ,a pleasure-loving character will have pleasure of some sort2 but1 if you give him the choice1 he may prefer pleasures which do not degrade him to those which do4 ,and this choice is offered to every man1 who possesses in literary or artistic culture a never-failing source of pleasures1 which are neither withered by age1 nor staled by custom1 nor embittered in the recollection by the pangs of self-reproach4 ,if the ,institution opened to-day fulfils the intention of its founder1 the picked intelligences among all classes of the population of this district will pass through it4 ,no child born in ,birmingham1 henceforward1 if he have the capacity to profit by the opportunities offered to him1 first in the primary and other schools1 and afterwards in the ,scientific ,college1 need fail to obtain1 not merely the instruction1 but the culture most appropriate to the conditions of his life4 ,within these walls1 the future employer and the future artisan may sojourn together for a while1 and carry1 through all their lives1 the stamp of the influences then brought to bear upon them4 ,hence1 it is not beside the mark to remind you1 that the prosperity of industry depends not merely upon the improvement of manufacturing processes1 not merely upon the ennobling of the individual character1 but upon a third condition1 namely1 a clear understanding of the conditions of social life on the part of both the capitalist and the operative1 and their agreement upon common principles of social action4 ,they must learn that social phenomena are as much the expression of natural laws as any others2 that no social arrangements can be permanent unless they harmonise with the requirements of social statics and dynamics2 and that1 in the nature of things1 there is an arbiter whose decisions execute themselves4 ,but this knowledge is only to be obtained by the application of the methods of investigation adopted in physical researches to the investigation of the phenomena of society4 ,hence1 ,i confess1 ,i should like to see one addition made to the excellent scheme of education propounded for the ,college1 in the shape of provision for the teaching of ,sociology4 ,for though we are all agreed that party politics are to have no place in the instruction of the ,college2 yet in this country1 practically governed as it is now by universal suffrage1 every man who does his duty must exercise political functions4 ,and1 if the evils which are inseparable from the good of political liberty are to be checked1 if the perpetual oscillation of nations between anarchy and despotism is to be replaced by the steady march of self-restraining freedom2 it will be because men will gradually bring themselves to deal with political1 as they now deal with scientific questions2 to be as ashamed of undue haste and partisan prejudice in the one case as in the other2 and to believe that the machinery of society is at least as delicate as that of a spinning-jenny1 and as little likely to be improved by the meddling of those who have not taken the trouble to master the principles of its action4 ,in conclusion1 ,i am sure that ,i make myself the mouthpiece of all present in offering to the venerable founder of the ,institution1 which now commences its beneficent career1 our congratulations on the completion of his work2 and in expressing the conviction1 that the remotest posterity will point to it as a crucial instance of the wisdom which natural piety leads all men to ascribe to their ancestors4 ,,ii4 ,,universities3 ,,actual ,,and ,,ideal4 ,elected by the suffrages of your four ,nations1 ,rector of the ancient ,university of which you are scholars1 ,i take the earliest opportunity which has presented itself since my restoration to health1 of delivering the ,address which1 by long custom1 is expected of the holder of my office4 ,my first duty in opening that ,address1 is to offer you my most hearty thanks for the signal honour you have conferred upon me--an honour of which1 as a man unconnected with you by personal or by national ties1 devoid of political distinction1 and a plebeian who stands by his order1 ,i could not have dreamed4 ,and it was the more surprising to me1 as the five-and-twenty years which have passed over my head since ,i reached intellectual manhood1 have been largely spent in no half-hearted advocacy of doctrines which have not yet found favour in the eyes of ,academic respectability2 so that1 when the proposal to nominate me for your ,rector came1 ,i was almost as much astonished as was ,hal o' the ,wynd1 8who fought for his own hand10 by the ,black ,douglas's proffer of knighthood4 ,and ,i fear that my acceptance must be taken as evidence that1 less wise than the ,armourer of ,perth1 ,i have not yet done with soldiering4 ,in fact1 if1 for a moment1 ,i imagined that your intention was simply1 in the kindness of your hearts1 to do me honour2 and that the ,rector of your ,university1 like that of some other ,universities1 was one of those happy beings who sit in glory for three years1 with nothing to do for it save the making of a speech1 a conversation with my distinguished predecessor soon dispelled the dream4 ,i found that1 by the constitution of the ,university of ,aberdeen1 the incumbent of the ,rectorate is1 if not a power1 at any rate a potential energy2 and that1 whatever may be his chances of success or failure1 it is his duty to convert that potential energy into a living force1 directed towards such ends as may seem to him conducive to the welfare of the corporation of which he is the theoretical head4 ,i need not tell you that your late ,lord ,rector took this view of his position1 and acted upon it with the comprehensive1 far-seeing insight into the actual condition and tendencies1 not merely of his own1 but of other countries1 which is his honourable characteristic among statesmen4 ,i have already done my best1 and1 as long as ,i hold my office1 ,i shall continue my endeavours1 to follow in the path which he trod2 to do what in me lies1 to bring this ,university nearer to the ideal--alas1 that ,i should be obliged to say ideal--of all ,universities2 which1 as ,i conceive1 should be places in which thought is free from all fetters2 and in which all sources of knowledge1 and all aids to learning1 should be accessible to all comers1 without distinction of creed or country1 riches or poverty4 ,do not suppose1 however1 that ,i am sanguine enough to expect much to come of any poor efforts of mine4 ,if your annals take any notice of my incumbency1 ,i shall probably go down to posterity as the ,rector who was always beaten4 ,but if they add1 as ,i think they will1 that my defeats became victories in the hands of my successors1 ,i shall be well content4 ,the scenes are shifting in the great theatre of the world4 ,the act which commenced with the ,protestant ,reformation is nearly played out1 and a wider and a deeper change than that effected three centuries ago--a reformation1 or rather a revolution of thought1 the extremes of which are represented by the intellectual heirs of ,john of ,leyden and of ,ignatius ,loyola1 rather than by those of ,luther and of ,leo--is waiting to come on1 nay1 visible behind the scenes to those who have good eyes4 ,men are beginning1 once more1 to awake to the fact that matters of belief and of speculation are of absolutely infinite practical importance2 and are drawing off from that sunny country 8where it is always afternoon0--the sleepy hollow of broad indifferentism--to range themselves under their natural banners4 ,change is in the air4 ,it is whirling feather-heads into all sorts of eccentric orbits1 and filling the steadiest with a sense of insecurity4 ,it insists on reopening all questions and asking all institutions1 however venerable1 by what right they exist1 and whether they are1 or are not1 in harmony with the real or supposed wants of mankind4 ,and it is remarkable that these searching inquiries are not so much forced on institutions from without1 as developed from within4 ,consummate scholars question the value of learning2 priests condemn dogma2 and women turn their backs upon man's ideal of perfect womanhood1 and seek satisfaction in apocalyptic visions of some1 as yet unrealised1 epicene reality4 ,if there be a type of stability in this world1 one would be inclined to look for it in the old ,universities of ,england4 ,but it has been my business of late to hear a good deal about what is going on in these famous corporations2 and ,i have been filled with astonishment by the evidences of internal fermentation which they exhibit4 ,if ,gibbon could revisit the ancient seat of learning of which he has written so cavalierly1 assuredly he would no longer speak of 8the monks of ,oxford sunk in prejudice and port40 ,there1 as elsewhere1 port has gone out of fashion1 and so has prejudice--at least that particular fine1 old1 crusted sort of prejudice to which the great historian alludes4 ,indeed1 things are moving so fast in ,oxford and ,cambridge1 that1 for my part1 ,i rejoiced when the ,royal ,commission1 of which ,i am a member1 had finished and presented the ,report which related to these ,universities2 for we should have looked like mere plagiarists1 if1 in consequence of a little longer delay in issuing it1 all the measures of reform we proposed had been anticipated by the spontaneous action of the ,universities themselves4 ,a month ago ,i should have gone on to say that one might speedily expect changes of another kind in ,oxford and ,cambridge4 ,a ,commission has been inquiring into the revenues of the many wealthy societies1 in more or less direct connection with the ,universities1 resident in those towns4 ,it is said that the ,commission has reported1 and that1 for the first time in recorded history1 the nation1 and perhaps the ,colleges themselves1 will know what they are worth4 ,and it was announced that a statesman1 who1 whatever his other merits or defects1 has aims above the level of mere party fighting1 and a clear vision into the most complex practical problems1 meant to deal with these revenues4 ,but1 ,bos locutus est4 ,that mysterious independent variable of political calculation1 ,public ,opinion--which some whisper is1 in the present case1 very much the same thing as publican's opinion--has willed otherwise4 ,the ,heads may return to their wonted slumbers--at any rate for a space4 ,is the spirit of change1 which is working thus vigorously in the ,south1 likely to affect the ,northern ,universities1 and if so1 to what extent8 ,the violence of fermentation depends1 not so much on the quantity of the yeast1 as on the composition of the wort1 and its richness in fermentable material2 and1 as a preliminary to the discussion of this question1 ,i venture to call to your minds the essential and fundamental differences between the ,scottish and the ,english type of ,university4 ,do not charge me with anything worse than official egotism1 if ,i say that these differences appear to be largely symbolised by my own existence4 ,there is no ,rector in an ,english ,university4 ,now1 the organisation of the members of an ,university into ,nations1 with their elective ,rector1 is the last relic of the primitive constitution of ,universities4 ,the ,rectorate was the most important of all offices in that ,university of ,paris1 upon the model of which the ,university of ,aberdeen was fashioned2 and which was certainly a great and flourishing institution in the twelfth century4 ,enthusiasts for the antiquity of one of the two acknowledged parents of all ,universities1 indeed1 do not hesitate to trace the origin of the 8,studium ,parisiense0 up to that wonderful king of the ,franks and ,lombards1 ,karl1 surnamed the ,great1 whom we all called ,charlemagne1 and believed to be a ,frenchman1 until a learned historian1 by beneficent iteration1 taught us better4 ,karl is said not to have been much of a scholar himself1 but he had the wisdom of which knowledge is only the servitor4 ,and that wisdom enabled him to see that ignorance is one of the roots of all evil4 ,in the ,capitulary which enjoins the foundation of monasterial and cathedral schools1 he says3 8,right action is better than knowledge2 but in order to do what is right1 we must know what is right40#d ,an irrefragable truth1 ,i fancy4 ,acting upon it1 the king took pretty full compulsory powers1 and carried into effect a really considerable and effectual scheme of elementary education through the length and breadth of his dominions4 ,no doubt the idolaters out by the ,elbe1 in what is now part of ,prussia1 objected to the ,frankish king's measures2 no doubt the priests1 who had never hesitated about sacrificing all unbelievers in their fantastic deities and futile conjurations1 were the loudest in chanting the virtues of toleration2 no doubt they denounced as a cruel persecutor the man who would not allow them1 however sincere they might be1 to go on spreading delusions which debased the intellect1 as much as they deadened the moral sense1 and undermined the bonds of civil allegiance2 no doubt1 if they had lived in these times1 they would have been able to show1 with ease1 that the king's proceedings were totally contrary to the best liberal principles4 ,but it may be said1 in justification of the ,teutonic ruler1 first1 that he was born before those principles1 and did not suspect that the best way of getting disorder into order was to let it alone2 and1 secondly1 that his rough and questionable proceedings did1 more or less1 bring about the end he had in view4 ,for1 in a couple of centuries1 the schools he sowed broadcast produced their crop of men1 thirsting for knowledge and craving for culture4 ,such men gravitating towards ,paris1 as a light amidst the darkness of evil days1 from ,germany1 from ,spain1 from ,britain1 and from ,scandinavia1 came together by natural affinity4 ,by degrees they banded themselves into a society1 which1 as its end was the knowledge of all things knowable1 called itself a 8,studium ,generale20 and when it had grown into a recognised corporation1 acquired the name of 8,universitas ,studii ,generalis10 which1 mark you1 means not a 8,useful ,knowledge ,society10 but a 8,knowledge-of-things-in-general ,society40 ,and thus the first 8,university10 at any rate on this side of the ,alps1 came into being4 ,originally it had but one ,faculty1 that of ,arts4 ,its aim was to be a centre of knowledge and culture2 not to be1 in any sense1 a technical school4 ,the scholars seem to have studied ,grammar1 ,logic1 and ,rhetoric2 ,arithmetic and ,geometry2 ,astronomy2 ,theology2 and ,music4 ,thus1 their work1 however imperfect and faulty1 judged by modern lights1 it may have been1 brought them face to face with all the leading aspects of the many-sided mind of man4 ,for these studies did really contain1 at any rate in embryo--sometimes1 it may be1 in caricature--what we now call ,philosophy1 ,mathematical and ,physical ,science1 and ,art4 ,and ,i doubt if the curriculum of any modern ,university shows so clear and generous a comprehension of what is meant by culture1 as this old ,trivium and ,quadrivium does4 ,the students who had passed through the ,university course1 and had proved themselves competent to teach1 became masters and teachers of their younger brethren4 ,whence the distinction of ,masters and ,regents on the one hand1 and ,scholars on the other4 ,rapid growth necessitated organisation4 ,the ,masters and ,scholars of various tongues and countries grouped themselves into four ,nations2 and the ,nations1 by their own votes at first1 and subsequently by those of their ,procurators1 or representatives1 elected their supreme head and governor1 the ,rector--at that time the sole representative of the ,university1 and a very real power1 who could defy ,provosts interfering from without2 or could inflict even corporal punishment on disobedient members within the ,university4 ,such was the primitive constitution of the ,university of ,paris4 ,it is in reference to this original state of things that ,i have spoken of the ,rectorate1 and all that appertains to it1 as the sole relic of that constitution4 ,but this original organisation did not last long4 ,society was not then1 any more than it is now1 patient of culture1 as such4 ,it says to everything1 8,be useful to me1 or away with you40 ,and to the learned1 the unlearned man said then1 as he does now1 8,what is the use of all your learning1 unless you can tell me what ,i want to know8 ,i am here blindly groping about1 and constantly damaging myself by collision with three mighty powers1 the power of the invisible ,god1 the power of my fellow ,man1 and the power of brute ,nature4 ,let your learning be turned to the study of these powers1 that ,i may know how ,i am to comport myself with regard to them40 ,in answer to this demand1 some of the ,masters of the ,faculty of ,arts devoted themselves to the study of ,theology1 some to that of ,law1 and some to that of ,medicine2 and they became ,doctors--men learned in those technical1 or1 as we now call them1 professional1 branches of knowledge4 ,like cleaving to like1 the ,doctors formed schools1 or ,faculties1 of ,theology1 ,law1 and ,medicine1 which sometimes assumed airs of superiority over their parent1 the ,faculty of ,arts1 though the latter always asserted and maintained its fundamental supremacy4 ,the ,faculties arose by process of natural differentiation out of the primitive ,university4 ,other constituents1 foreign to its nature1 were speedily grafted upon it4 ,one of these extraneous elements was forced into it by the ,roman ,church1 which in those days asserted with effect1 that which it now asserts1 happily without any effect in these realms1 its right of censorship and control over all teaching4 ,the local habitation of the ,university lay partly in the lands attached to the monastery of ,s4 ,genevive1 partly in the diocese of the ,bishop of ,paris2 and he who would teach must have the licence of the ,abbot1 or of the ,bishop1 as the nearest representative of the ,pope1 so to do1 which licence was granted by the ,chancellors of these ,ecclesiastics4 ,thus1 if ,i am what archologists call a 8survival0 of the primitive head and ruler of the ,university1 your ,chancellor stands in the same relation to the ,papacy2 and1 with all respect for his ,grace1 ,i think ,i may say that we both look terribly shrunken when compared with our great originals4 ,not so is it with a second foreign element1 which silently dropped into the soil of ,universities1 like the grain of mustard-seed in the parable2 and1 like that grain1 grew into a tree1 in whose branches a whole aviary of fowls took shelter4 ,that element is the element of ,endowment4 ,it differed from the preceding1 in its original design to serve as a prop to the young plant1 not to be a parasite upon it4 ,the charitable and the humane1 blessed with wealth1 were very early penetrated by the misery of the poor student4 ,and the wise saw that intellectual ability is not so common or so unimportant a gift that it should be allowed to run to waste upon mere handicrafts and chares4 ,the man who was a blessing to his contemporaries1 but who so often has been converted into a curse1 by the blind adherence of his posterity to the letter1 rather than to the spirit1 of his wishes--,i mean the 8pious founder0--gave money and lands1 that the student1 who was rich in brain and poor in all else1 might be taken from the plough or from the stithy1 and enabled to devote himself to the higher service of mankind2 and built colleges and halls in which he might be not only housed and fed1 but taught4 ,the ,colleges were very generally placed in strict subordination to the ,university by their founders2 but1 in many cases1 their endowment1 consisting of land1 has undergone an 8unearned increment10 which has given these societies a continually increasing weight and importance as against the unendowed1 or fixedly endowed1 ,university4 ,in ,pharaoh's dream1 the seven lean kine eat up the seven fat ones4 ,in the reality of historical fact1 the fat ,colleges have eaten up the lean ,universities4 ,even here in ,aberdeen1 though the causes at work may have been somewhat different1 the effects have been similar2 and you see how much more substantial an entity is the ,very ,reverend the ,principal1 analogue1 if not homologue1 of the ,principals of ,king's ,college1 than the ,rector1 lineal representative of the ancient monarchs of the ,university1 though now1 little more than a 8king of shreds and patches40 ,do not suppose that1 in thus briefly tracing the process of ,university metamorphosis1 ,i have had any intention of quarrelling with its results4 ,practically1 it seems to me that the broad changes effected in #aheh have given the ,scottish ,universities a very liberal constitution1 with as much real approximation to the primitive state of things as is at all desirable4 ,if your fat kine have eaten the lean1 they have not lain down to chew the cud ever since4 ,the ,scottish ,universities1 like the ,english1 have diverged widely enough from their primitive model2 but ,i cannot help thinking that the northern form has remained more faithful to its original1 not only in constitution1 but1 what is more to the purpose1 in view of the cry for change1 in the practical application of the endowments connected with it4 ,in ,aberdeen1 these endowments are numerous1 but so small that1 taken altogether1 they are not equal to the revenue of a single third-rate ,english college4 ,they are scholarships1 not fellowships2 aids to do work--not rewards for such work as it lies within the reach of an ordinary1 or even an extraordinary1 young man to do4 ,you do not think that passing a respectable examination is a fair equivalent for an income1 such as many a gray-headed veteran1 or clergyman1 would envy2 and which is larger than the endowment of many ,regius chairs4 ,you do not care to make your ,university a school of manners for the rich2 of sports for the athletic2 or a hot-bed of high-fed1 hypercritical refinement1 more destructive to vigour and originality than are starvation and oppression4 ,no2 your little ,bursaries of ten and twenty 7,i believe even fifty7 pounds a year1 enable any boy who has shown ability in the course of his education in those remarkable primary schools1 which have made ,scotland the power she is1 to obtain the highest culture the country can give him2 and when he is armed and equipped1 his ,spartan ,alma ,mater tells him that1 so far1 he has had his wages for his work1 and that he may go and earn the rest4 ,when ,i think of the host of pleasant1 monied1 well-bred young gentlemen1 who do a little learning and much boating by ,cam and ,isis1 the vision is a pleasant one2 and1 as a patriot1 ,i rejoice that the youth of the upper and richer classes of the nation receive a wholesome and a manly training1 however small may be the modicum of knowledge they gather1 in the intervals of this1 their serious business4 ,i admit1 to the full1 the social and political value of that training4 ,but1 when ,i proceed to consider that these young men may be said to represent the great bulk of what the ,colleges have to show for their enormous wealth1 plus1 at least1 a hundred and fifty pounds a year apiece which each undergraduate costs his parents or guardians1 ,i feel inclined to ask1 whether the rate-in-aid of the education of the wealthy and professional classes1 thus levied on the resources of the community1 is not1 after all1 a little heavy8 ,and1 still further1 ,i am tempted to inquire what has become of the indigent scholars1 the sons of the masses of the people whose daily labour just suffices to meet their daily wants1 for whose benefit these rich foundations were largely1 if not mainly1 instituted8 ,it seems as if ,pharaoh's dream had been rigorously carried out1 and that even the fat scholar has eaten the lean one4 ,and when ,i turn from this picture to the no less real vision of many a brave and frugal ,scotch boy1 spending his summer in hard manual labour1 that he may have the privilege of wending his way in autumn to this ,university1 with a bag of oatmeal1 ten pounds in his pocket1 and his own stout heart to depend upon through the northern winter2 not bent on seeking 8,the bubble reputation at the cannon's mouth10 but determined to wring knowledge from the hard hands of penury2 when ,i see him win through all such outward obstacles to positions of wide usefulness and well-earned fame2 ,i cannot but think that1 in essence1 ,aberdeen has departed but little from the primitive intention of the founders of ,universities1 and that the spirit of reform has so much to do on the other side of the ,border1 that it may be long before he has leisure to look this way4 ,as compared with other actual ,universities1 then1 ,aberdeen1 may1 perhaps1 be well satisfied with itself4 ,but do not think me an impracticable dreamer1 if ,i ask you not to rest and be thankful in this state of satisfaction2 if ,i ask you to consider awhile1 how this actual good stands related to that ideal better1 towards which both men and institutions must progress1 if they would not retrograde4 ,in an ideal ,university1 as ,i conceive it1 a man should be able to obtain instruction in all forms of knowledge1 and discipline in the use of all the methods by which knowledge is obtained4 ,in such an ,university1 the force of living example should fire the student with a noble ambition to emulate the learning of learned men1 and to follow in the footsteps of the explorers of new fields of knowledge4 ,and the very air he breathes should be charged with that enthusiasm for truth1 that fanaticism of veracity1 which is a greater possession than much learning2 a nobler gift than the power of increasing knowledge2 by so much greater and nobler than these1 as the moral nature of man is greater than the intellectual2 for veracity is the heart of morality4 ,but the man who is all morality and intellect1 although he may be good and even great1 is1 after all1 only half a man4 ,there is beauty in the moral world and in the intellectual world2 but there is also a beauty which is neither moral nor intellectual--the beauty of the world of ,art4 ,there are men who are devoid of the power of seeing it1 as there are men who are born deaf and blind1 and the loss of those1 as of these1 is simply infinite4 ,there are others in whom it is an overpowering passion2 happy men1 born with the productive1 or at lowest1 the appreciative1 genius of the ,artist4 ,but1 in the mass of mankind1 the sthetic faculty1 like the reasoning power and the moral sense1 needs to be roused1 directed1 and cultivated2 and ,i know not why the development of that side of his nature1 through which man has access to a perennial spring of ennobling pleasure1 should be omitted from any comprehensive scheme of ,university education4 ,all ,universities recognise ,literature in the sense of the old ,rhetoric1 which is art incarnate in words4 ,some1 to their credit1 recognise ,art in its narrower sense1 to a certain extent1 and confer degrees for proficiency in some of its branches4 ,if there are ,doctors of ,music1 why should there be no ,masters of ,painting1 of ,sculpture1 of ,architecture8 ,i should like to see ,professors of the ,fine ,arts in every ,university2 and instruction in some branch of their work made a part of the ,arts curriculum4 ,i just now expressed the opinion that1 in our ideal ,university1 a man should be able to obtain instruction in all forms of knowledge4 ,now1 by 8forms of knowledge0 ,i mean the great classes of things knowable2 of which the first1 in logical1 though not in natural1 order is knowledge relating to the scope and limits of the mental faculties of man2 a form of knowledge which1 in its positive aspect1 answers pretty much to ,logic and part of ,psychology1 while1 on its negative and critical side1 it corresponds with ,metaphysics4 ,a second class comprehends all that knowledge which relates to man's welfare1 so far as it is determined by his own acts1 or what we call his conduct4 ,it answers to ,moral and ,religious philosophy4 ,practically1 it is the most directly valuable of all forms of knowledge1 but speculatively1 it is limited and criticised by that which precedes and by that which follows it in my order of enumeration4 ,a third class embraces knowledge of the phenomena of the ,universe1 as that which lies about the individual man3 and of the rules which those phenomena are observed to follow in the order of their occurrence1 which we term the laws of ,nature4 ,this is what ought to be called ,natural ,science1 or ,physiology1 though those terms are hopelessly diverted from such a meaning2 and it includes all exact knowledge of natural fact1 whether ,mathematical1 ,physical1 ,biological1 or ,social4 ,kant has said that the ultimate object of all knowledge is to give replies to these three questions3 ,what can ,i do8 ,what ought ,i to do8 ,what may ,i hope for8 ,the forms of knowledge which ,i have enumerated1 should furnish such replies as are within human reach1 to the first and second of these questions4 ,while to the third1 perhaps the wisest answer is1 8,do what you can to do what you ought1 and leave hoping and fearing alone40 ,if this be a just and an exhaustive classification of the forms of knowledge1 no question as to their relative importance1 or as to the superiority of one to the other1 can be seriously raised4 ,on the face of the matter1 it is absurd to ask whether it is more important to know the limits of one's powers2 or the ends for which they ought to be exerted2 or the conditions under which they must be exerted4 ,one may as well inquire which of the terms of a ,rule of ,three sum one ought to know1 in order to get a trustworthy result4 ,practical life is such a sum1 in which your duty multiplied into your capacity1 and divided by your circumstances1 gives you the fourth term in the proportion1 which is your deserts1 with great accuracy4 ,all agree1 ,i take it1 that men ought to have these three kinds of knowledge4 ,the so-called 8conflict of studies0 turns upon the question of how they may best be obtained4 ,the founders of ,universities held the theory that the ,scriptures and ,aristotle taken together1 the latter being limited by the former1 contained all knowledge worth having1 and that the business of philosophy was to interpret and co-ordinate these two4 ,i imagine that in the twelfth century this was a very fair conclusion from known facts4 ,nowhere in the world1 in those days1 was there such an encyclopdia of knowledge of all three classes1 as is to be found in those writings4 ,the scholastic philosophy is a wonderful monument of the patience and ingenuity with which the human mind toiled to build up a logically consistent theory of the ,universe1 out of such materials4 ,and that philosophy is by no means dead and buried1 as many vainly suppose4 ,on the contrary1 numbers of men of no mean learning and accomplishment1 and sometimes of rare power and subtlety of thought1 hold by it as the best theory of things which has yet been stated4 ,and1 what is still more remarkable1 men who speak the language of modern philosophy1 nevertheless think the thoughts of the schoolmen4 8,the voice is the voice of ,jacob1 but the hands are the hands of ,esau40 ,every day ,i hear 8,cause10 8,law10 8,force10 8,vitality10 spoken of as entities1 by people who can enjoy ,swift's joke about the meat-roasting quality of the smoke-jack1 and comfort themselves with the reflection that they are not even as those benighted schoolmen4 ,well1 this great system had its day1 and then it was sapped and mined by two influences4 ,the first was the study of classical literature1 which familiarised men with methods of philosophising2 with conceptions of the highest ,good2 with ideas of the order of ,nature2 with notions of ,literary and ,historical ,criticism2 and1 above all1 with visions of ,art1 of a kind which not only would not fit into the scholastic scheme1 but showed them a pre-,christian1 and indeed altogether un-,christian world1 of such grandeur and beauty that they ceased to think of any other4 ,they were as men who had kissed the ,fairy ,queen1 and wandering with her in the dim loveliness of the underworld1 cared not to return to the familiar ways of home and fatherland1 though they lay1 at arm's length1 overhead4 ,cardinals were more familiar with ,virgil than with ,isaiah2 and ,popes laboured1 with great success1 to re-paganise ,rome4 ,the second influence was the slow1 but sure1 growth of the physical sciences4 ,it was discovered that some results of speculative thought1 of immense practical and theoretical importance1 can be verified by observation2 and are always true1 however severely they may be tested4 ,here1 at any rate1 was knowledge1 to the certainty of which no authority could add1 or take away1 one jot or tittle1 and to which the tradition of a thousand years was as insignificant as the hearsay of yesterday4 ,to the scholastic system1 the study of classical literature might be inconvenient and distracting1 but it was possible to hope that it could be kept within bounds4 ,physical science1 on the other hand1 was an irreconcilable enemy1 to be excluded at all hazards4 ,the ,college of ,cardinals has not distinguished itself in ,physics or ,physiology2 and no ,pope has1 as yet1 set up public laboratories in the ,vatican4 ,people do not always formulate the beliefs on which they act4 ,the instinct of fear and dislike is quicker than the reasoning process2 and ,i suspect that1 taken in conjunction with some other causes1 such instinctive aversion is at the bottom of the long exclusion of any serious discipline in the physical sciences from the general curriculum of ,universities2 while1 on the other hand1 classical literature has been gradually made the backbone of the ,arts course4 ,i am ashamed to repeat here what ,i have said elsewhere1 in season and out of season1 respecting the value of ,science as knowledge and discipline4 ,but the other day ,i met with some passages in the ,address to another ,scottish ,university1 of a great thinker1 recently lost to us1 which express so fully1 and yet so tersely1 the truth in this matter1 that ,i am fain to quote them3-- 8,to question all things2--never to turn away from any difficulty2 to accept no doctrine either from ourselves or from other people without a rigid scrutiny by negative criticism2 letting no fallacy1 or incoherence1 or confusion of thought step by unperceived2 above all1 to insist upon having the meaning of a word clearly understood before using it1 and the meaning of a proposition before assenting to it2--these are the lessons we learn0 from workers in ,science4 8,with all this vigorous management of the negative element1 they inspire no scepticism about the reality of truth or indifference to its pursuit4 ,the noblest enthusiasm1 both for the search after truth and for applying it to its highest uses1 pervades those writers40 8,in cultivating1 therefore10 science as an essential ingredient in education1 8we are all the while laying an admirable foundation for ethical and philosophical culture40#e ,the passages ,i have quoted were uttered by ,john ,stuart ,mill2 but you cannot hear inverted commas1 and it is therefore right that ,i should add1 without delay1 that ,i have taken the liberty of substituting 8workers in science0 for 8ancient dialecticians10 and 8,science as an essential ingredient in education0 for 8the ancient languages as our best literary education40 ,mill did1 in fact1 deliver a noble panegyric upon classical studies4 ,i do not doubt its justice1 nor presume to question its wisdom4 ,but ,i venture to maintain that no wise or just judge1 who has a knowledge of the facts1 will hesitate to say that it applies with equal force to scientific training4 ,but it is only fair to the ,scottish ,universities to point out that they have long understood the value of ,science as a branch of general education4 ,i observe1 with the greatest satisfaction1 that candidates for the degree of ,master of ,arts in this ,university are required to have a knowledge1 not only of ,mental and ,moral ,philosophy1 and of ,mathematics and ,natural ,philosophy1 but of ,natural ,history1 in addition to the ordinary ,latin and ,greek course2 and that a candidate may take honours in these subjects and in ,chemistry4 ,i do not know what the requirements of your examiners may be1 but ,i sincerely trust they are not satisfied with a mere book knowledge of these matters4 ,for my own part1 ,i would not raise a finger1 if ,i could thereby introduce mere book work in science into every ,arts curriculum in the country4 ,let those who want to study books devote themselves to ,literature1 in which we have the perfection of books1 both as to substance and as to form4 ,if ,i may paraphrase ,hobbes's well-known aphorism1 ,i would say that 8books are the money of ,literature1 but only the counters of ,science10 ,science 7in the sense in which ,i now use the term7 being the knowledge of fact1 of which every verbal description is but an incomplete and symbolic expression4 ,and be assured that no teaching of science is worth anything1 as a mental discipline1 which is not based upon direct perception of the facts1 and practical exercise of the observing and logical faculties upon them4 ,even in such a simple matter as the mere comprehension of form1 ask the most practised and widely informed anatomist what is the difference between his knowledge of a structure which he has read about1 and his knowledge of the same structure when he has seen it for himself2 and he will tell you that the two things are not comparable--the difference is infinite4 ,thus ,i am very strongly inclined to agree with some learned school-masters who say that1 in their experience1 the teaching of science is all waste time4 ,as they teach it1 ,i have no doubt it is4 ,but to teach it otherwise1 requires an amount of personal labour and a development of means and appliances1 which must strike horror and dismay into a man accustomed to mere book work2 and who has been in the habit of teaching a class of fifty without much strain upon his energies4 ,and this is one of the real difficulties in the way of the introduction of physical science into the ordinary ,university course1 to which ,i have alluded4 ,it is a difficulty which will not be overcome1 until years of patient study have organised scientific teaching as well as1 or ,i hope better than1 classical teaching has been organised hitherto4 ,a little while ago1 ,i ventured to hint a doubt as to the perfection of some of the arrangements in the ancient ,universities of ,england2 but1 in their provision for giving instruction in ,science as such1 and without direct reference to any of its practical applications1 they have set a brilliant example4 ,within the last twenty years1 ,oxford alone has sunk more than a hundred and twenty thousand pounds in building and furnishing ,physical1 ,chemical1 and ,physiological ,laboratories1 and a magnificent ,museum1 arranged with an almost luxurious regard for the needs of the student4 ,cambridge1 less rich1 but aided by the munificence of her ,chancellor1 is taking the same course2 and1 in a few years1 it will be for no lack of the means and appliances of sound teaching1 if the mass of ,english ,university men remain in their present state of barbarous ignorance of even the rudiments of scientific culture4 ,yet another step needs to be made before ,science can be said to have taken its proper place in the ,universities4 ,that is its recognition as a ,faculty1 or branch of study demanding recognition and special organisation1 on account of its bearing on the wants of mankind4 ,the ,faculties of ,theology1 ,law1 and ,medicine1 are technical schools1 intended to equip men who have received general culture1 with the special knowledge which is needed for the proper performance of the duties of clergymen1 lawyers1 and medical practitioners4 ,when the material well-being of the country depended upon rude pasture and agriculture1 and still ruder mining2 in the days when all the innumerable applications of the principles of physical science to practical purposes were non-existent even as dreams2 days which men living may have heard their fathers speak of2 what little physical science could be seen to bear directly upon human life1 lay within the province of ,medicine4 ,medicine was the foster-mother of ,chemistry1 because it has to do with the preparation of drugs and the detection of poisons2 of ,botany1 because it enabled the physician to recognise medicinal herbs2 of ,comparative ,anatomy and ,physiology1 because the man who studied ,human ,anatomy and ,physiology for purely medical purposes was led to extend his studies to the rest of the animal world4 ,within my recollection1 the only way in which a student could obtain anything like a training in ,physical ,science1 was by attending the lectures of the ,professors of ,physical and ,natural ,science attached to the ,medical ,schools4 ,but1 in the course of the last thirty years1 both foster-mother and child have grown so big1 that they threaten not only to crush one another1 but to press the very life out of the unhappy student who enters the nursery2 to the great detriment of all three4 ,i speak in the presence of those who know practically what medical education is2 for ,i may assume that a large proportion of my hearers are more or less advanced students of medicine4 ,i appeal to the most industrious and conscientious among you1 to those who are most deeply penetrated with a sense of the extremely serious responsibilities which attach to the calling of a medical practitioner1 when ,i ask whether1 out of the four years which you devote to your studies1 you ought to spare even so much as an hour for any work which does not tend directly to fit you for your duties8 ,consider what that work is4 ,its foundation is a sound and practical acquaintance with the structure of the human organism1 and with the modes and conditions of its action in health4 ,i say a sound and practical acquaintance1 to guard against the supposition that my intention is to suggest that you ought all to be minute anatomists and accomplished physiologists4 ,the devotion of your whole four years to ,anatomy and ,physiology alone1 would be totally insufficient to attain that end4 ,what ,i mean is1 the sort of practical1 familiar1 finger-end knowledge which a watchmaker has of a watch1 and which you expect that craftsman1 as an honest man1 to have1 when you entrust a watch that goes badly1 to him4 ,it is a kind of knowledge which is to be acquired1 not in the lecture-room1 nor in the library1 but in the dissecting-room and the laboratory4 ,it is to be had1 not by sharing your attention between these and sundry other subjects1 but by concentrating your minds1 week after week1 and month after month1 six or seven hours a day1 upon all the complexities of organ and function1 until each of the greater truths of anatomy and physiology has become an organic part of your minds--until you would know them if you were roused and questioned in the middle of the night1 as a man knows the geography of his native place and the daily life of his home4 ,that is the sort of knowledge which1 once obtained1 is a life-long possession4 ,other occupations may fill your minds--it may grow dim1 and seem to be forgotten--but there it is1 like the inscription on a battered and defaced coin1 which comes out when you warm it4 ,if ,i had the power to remodel ,medical ,education1 the first two years of the medical curriculum should be devoted to nothing but such thorough study of ,anatomy and ,physiology1 with ,physiological ,chemistry and ,physics2 the student should then pass a real1 practical examination in these subjects2 and1 having gone through that ordeal satisfactorily1 he should be troubled no more with them4 ,his whole mind should then be given with equal intentness1 to ,therapeutics1 in its broadest sense1 to ,practical ,medicine and to ,surgery1 with instruction in ,hygiene and in ,medical ,jurisprudence2 and of these subjects only--surely there are enough of them--should he be required to show a knowledge in his final examination4 ,i cannot claim any special property in this theory of what the medical curriculum should be1 for ,i find that views1 more or less closely approximating these1 are held by all who have seriously considered the very grave and pressing question of ,medical ,reform2 and have1 indeed1 been carried into practice1 to some extent1 by the most enlightened ,examining ,boards4 ,i have heard but two kinds of objections to them4 ,there is1 first1 the objection of vested interests1 which ,i will not deal with here1 because ,i want to make myself as pleasant as ,i can1 and no discussions are so unpleasant as those which turn on such points4 ,and there is1 secondly1 the much more respectable objection1 which takes the general form of the reproach that1 in thus limiting the curriculum1 we are seeking to narrow it4 ,we are told that the medical man ought to be a person of good education and general information1 if his profession is to hold its own among other professions2 that he ought to know ,botany1 or else1 if he goes abroad1 he will not be able to tell poisonous fruits from edible ones2 that he ought to know drugs1 as a druggist knows them1 or he will not be able to tell sham bark and senna from the real articles2 that he ought to know ,zoology1 because--well1 ,i really have never been able to learn exactly why he is to be expected to know zoology4 ,there is1 indeed1 a popular superstition1 that doctors know all about things that are queer or nasty to the general mind1 and may1 therefore1 be reasonably expected to know the 8barbarous binomials0 applicable to snakes1 snails1 and slugs2 an amount of information with which the general mind is usually completely satisfied4 ,and there is a scientific superstition that ,physiology is largely aided by ,comparative ,anatomy--a superstition which1 like most superstitions1 once had a grain of truth at bottom2 but the grain has become homopathic1 since ,physiology took its modern experimental development1 and became what it is now1 the application of the principles of ,physics and ,chemistry to the elucidation of the phenomena of life4 ,i hold as strongly as any one can do1 that the medical practitioner ought to be a person of education and good general culture2 but ,i also hold by the old theory of a ,faculty1 that a man should have his general culture before he devotes himself to the special studies of that ,faculty2 and ,i venture to maintain1 that1 if the general culture obtained in the ,faculty of ,arts were what it ought to be1 the student would have quite as much knowledge of the fundamental principles of ,physics1 of ,chemistry1 and of ,biology1 as he needs1 before he commenced his special medical studies4 ,moreover1 ,i would urge1 that a thorough study of ,human ,physiology is1 in itself1 an education broader and more comprehensive than much that passes under that name4 ,there is no side of the intellect which it does not call into play1 no region of human knowledge into which either its roots1 or its branches1 do not extend2 like the ,atlantic between the ,old and the ,new ,worlds1 its waves wash the shores of the two worlds of matter and of mind2 its tributary streams flow from both2 through its waters1 as yet unfurrowed by the keel of any ,columbus1 lies the road1 if such there be1 from the one to the other2 far away from that ,north-west ,passage of mere speculation1 in which so many brave souls have been hopelessly frozen up4 ,but whether ,i am right or wrong about all this1 the patent fact of the limitation of time remains4 ,as the song runs3-- 8,if a man could be sure ,that his life would endure ,for the space of a thousand long years----0 he might do a number of things not practicable under present conditions4 ,methuselah might1 with much propriety1 have taken half a century to get his doctor's degree2 and might1 very fairly1 have been required to pass a practical examination upon the contents of the ,british ,museum1 before commencing practice as a promising young fellow of two hundred1 or thereabouts4 ,but you have four years to do your work in1 and are turned loose1 to save or slay1 at two or three and twenty4 ,now1 ,i put it to you1 whether you think that1 when you come down to the realities of life--when you stand by the sick-bed1 racking your brains for the principles which shall furnish you with the means of interpreting symptoms1 and forming a rational theory of the condition of your patient1 it will be satisfactory for you to find that those principles are not there--although1 to use the examination slang which is unfortunately too familiar to me1 you can quite easily 8give an account of the leading peculiarities of the ,marsupialia10 or 8enumerate the chief characters of the ,composit10 or 8state the class and order of the animal from which ,castoreum is obtained40 ,i really do not think that state of things will be satisfactory to you2 ,i am very sure it will not be so to your patient4 ,indeed1 ,i am so narrow-minded myself1 that if ,i had to choose between two physicians--one who did not know whether a whale is a fish or not1 and could not tell gentian from ginger1 but did understand the applications of the institutes of medicine to his art2 while the other1 like ,talleyrand's doctor1 8knew everything1 even a little physic0--with all my love for breadth of culture1 ,i should assuredly consult the former4 ,it is not pleasant to incur the suspicion of an inclination to injure or depreciate particular branches of knowledge4 ,but the fact that one of those which ,i should have no hesitation in excluding from the medical curriculum1 is that to which my own life has been specially devoted1 should1 at any rate1 defend me from the suspicion of being urged to this course by any but the very gravest considerations of the public welfare4 ,and ,i should like1 further1 to call your attention to the important circumstance that1 in thus proposing the exclusion of the study of such branches of knowledge as ,zoology and ,botany1 from those compulsory upon the medical student1 ,i am not1 for a moment1 suggesting their exclusion from the ,university4 ,i think that sound and practical instruction in the elementary facts and broad principles of ,biology should form part of the ,arts ,curriculum3 and here1 happily1 my theory is in entire accordance with your practice4 ,moreover1 as ,i have already said1 ,i have no sort of doubt that1 in view of the relation of ,physical ,science to the practical life of the present day1 it has the same right as ,theology1 ,law1 and ,medicine1 to a ,faculty of its own in which men shall be trained to be professional men of science4 ,it may be doubted whether ,universities are the places for technical schools of ,engineering1 or ,applied ,chemistry1 or ,agriculture4 ,but there can surely be little question1 that instruction in the branches of ,science which lie at the foundation of these ,arts1 of a far more advanced and special character than could1 with any propriety1 be included in the ordinary ,arts ,curriculum1 ought to be obtainable by means of a duly organised ,faculty of ,science in every ,university4 ,the establishment of such a ,faculty would have the additional advantage of providing1 in some measure1 for one of the greatest wants of our time and country4 ,i mean the proper support and encouragement of original research4 ,the other day1 an emphatic friend of mine committed himself to the opinion that1 in ,england1 it is better for a man's worldly prospects to be a drunkard1 than to be smitten with the divine dipsomania of the original investigator4 ,i am inclined to think he was not far wrong4 ,and1 be it observed1 that the question is not1 whether such a man shall be able to make as much out of his abilities as his brother1 of like ability1 who goes into ,law1 or ,engineering1 or ,commerce2 it is not a question of 8maintaining a due number of saddle horses10 as ,george ,eliot somewhere puts it--it is a question of living or starving4 ,if a student of my own subject shows power and originality1 ,i dare not advise him to adopt a scientific career2 for1 supposing he is able to maintain himself until he has attained distinction1 ,i cannot give him the assurance that any amount of proficiency in the ,biological ,sciences will be convertible into1 even the most modest1 bread and cheese4 ,and ,i believe that the case is as bad1 or perhaps worse1 with other branches of ,science4 ,in this respect ,britain1 whose immense wealth and prosperity hang upon the thread of ,applied ,science1 is far behind ,france1 and infinitely behind ,germany4 ,and the worst of it is1 that it is very difficult to see one's way to any immediate remedy for this state of affairs which shall be free from a tendency to become worse than the disease4 ,great schemes for the ,endowment of ,research have been proposed4 ,it has been suggested1 that ,laboratories for all branches of ,physical ,science1 provided with every apparatus needed by the investigator1 shall be established by the ,state3 and shall be accessible1 under due conditions and regulations1 to all properly qualified persons4 ,i see no objection to the principle of such a proposal4 ,if it be legitimate to spend great sums of money on public ,libraries and public collections of ,painting and ,sculpture1 in aid of the man of letters1 or the ,artist1 or for the mere sake of affording pleasure to the general public1 ,i apprehend that it cannot be illegitimate to do as much for the promotion of scientific investigation4 ,to take the lowest ground1 as a mere investment of money1 the latter is likely to be much more immediately profitable4 ,to my mind1 the difficulty in the way of such schemes is not theoretical1 but practical4 ,given the laboratories1 how are the investigators to be maintained8 ,what career is open to those who have been thus encouraged to leave bread-winning pursuits8 ,if they are to be provided for by endowment1 we come back to the ,college ,fellowship system1 the results of which1 for ,literature1 have not been so brilliant that one would wish to see it extended to ,science2 unless some much better securities1 than at present exist1 can be taken that it will foster real work4 ,you know that among the ,bees1 it depends on the kind of cell in which the egg is deposited1 and the quantity and quality of food which is supplied to the grub1 whether it shall turn out a busy little worker or a big idle queen4 ,and1 in the human hive1 the cells of the endowed larv are always tending to enlarge1 and their food to improve1 until we get queens1 beautiful to behold1 but which gather no honey and build no comb4 ,i do not say that these difficulties may not be overcome1 but their gravity is not to be lightly estimated4 ,in the meanwhile1 there is one step in the direction of the endowment of research which is free from such objections4 ,it is possible to place the scientific inquirer in a position in which he shall have ample leisure and opportunity for original work1 and yet shall give a fair and tangible equivalent for those privileges4 ,the establishment of a ,faculty of ,science in every ,university1 implies that of a corresponding number of ,professorial chairs1 the incumbents of which need not be so burdened with teaching as to deprive them of ample leisure for original work4 ,i do not think that it is any impediment to an original investigator to have to devote a moderate portion of his time to lecturing1 or superintending practical instruction4 ,on the contrary1 ,i think it may be1 and often is1 a benefit to be obliged to take a comprehensive survey of your subject2 or to bring your results to a point1 and give them1 as it were1 a tangible objective existence4 ,the besetting sins of the investigator are two3 the one is the desire to put aside a subject1 the general bearings of which he has mastered himself1 and pass on to something which has the attraction of novelty2 and the other1 the desire for too much perfection1 which leads him to 8,add and alter many times1 ,till all be ripe and rotten20 to spend the energies which should be reserved for action1 in whitening the decks and polishing the guns4 ,the obligation to produce results for the instruction of others1 seems to me to be a more effectual check on these tendencies1 than even the love of usefulness or the ambition for fame4 ,but supposing the ,professorial forces of our ,university to be duly organised1 there remains an important question1 relating to the teaching power1 to be considered4 ,is the ,professorial system--the system1 ,i mean1 of teaching in the lecture-room alone1 and leaving the student to find his own way when he is outside the lecture-room--adequate to the wants of learners8 ,in answering this question1 ,i confine myself to my own province1 and ,i venture to reply for ,physical ,science1 assuredly and undoubtedly1 ,no4 ,as ,i have already intimated1 practical work in the ,laboratory is absolutely indispensable1 and that practical work must be guided and superintended by a sufficient staff of ,demonstrators1 who are for ,science what ,tutors are for other branches of study4 ,and there must be a good supply of such ,demonstrators4 ,i doubt if the practical work of more than twenty students can be properly superintended by one ,demonstrator4 ,if we take the working day at six hours1 that is less than twenty minutes apiece--not a very large allowance of time for helping a dull man1 for correcting an inaccurate one1 or even for making an intelligent student clearly apprehend what he is about4 ,and1 no doubt1 the supplying of a proper amount of this tutorial1 practical teaching1 is a difficulty in the way of giving proper instruction in ,physical ,science in such ,universities as that of ,aberdeen1 which are devoid of endowments2 and1 unlike the ,english ,universities1 have no moral claim on the funds of richly endowed bodies to supply their wants4 ,examination--thorough1 searching examination--is an indispensable accompaniment of teaching2 but ,i am almost inclined to commit myself to the very heterodox proposition that it is a necessary evil4 ,i am a very old ,examiner1 having1 for some twenty years past1 been occupied with examinations on a considerable scale1 of all sorts and conditions of men1 and women too1--from the boys and girls of elementary schools to the candidates for ,honours and ,fellowships in the ,universities4 ,i will not say that1 in this case as in so many others1 the adage1 that familiarity breeds contempt1 holds good2 but my admiration for the existing system of examination and its products1 does not wax warmer as ,i see more of it4 ,examination1 like fire1 is a good servant1 but a bad master2 and there seems to me to be some danger of its becoming our master4 ,i by no means stand alone in this opinion4 ,experienced friends of mine do not hesitate to say that students whose career they watch1 appear to them to become deteriorated by the constant effort to pass this or that examination1 just as we hear of men's brains becoming affected by the daily necessity of catching a train4 ,they work to pass1 not to know2 and outraged ,science takes her revenge4 ,they do pass1 and they don't know4 ,i have passed sundry examinations in my time1 not without credit1 and ,i confess ,i am ashamed to think how very little real knowledge underlay the torrent of stuff which ,i was able to pour out on paper4 ,in fact1 that which examination1 as ordinarily conducted1 tests1 is simply a man's power of work under stimulus1 and his capacity for rapidly and clearly producing that which1 for the time1 he has got into his mind4 ,now1 these faculties are by no means to be despised4 ,they are of great value in practical life1 and are the making of many an advocate1 and of many a so-called statesman4 ,but in the pursuit of truth1 scientific or other1 they count for very little1 unless they are supplemented by that long-continued1 patient 8intending of the mind10 as ,newton phrased it1 which makes very little show in ,examinations4 ,i imagine that an ,examiner who knows his students personally1 must not unfrequently have found himself in the position of finding ,a's paper better than ,b's1 though his own judgment tells him1 quite clearly1 that ,b is the man who has the larger share of genuine capacity4 ,again1 there is a fallacy about ,examiners4 ,it is commonly supposed that any one who knows a subject is competent to teach it2 and no one seems to doubt that any one who knows a subject is competent to examine in it4 ,i believe both these opinions to be serious mistakes3 the latter1 perhaps1 the more serious of the two4 ,in the first place1 ,i do not believe that any one who is not1 or has not been1 a teacher is really qualified to examine advanced students4 ,and in the second place1 ,examination is an ,art1 and a difficult one1 which has to be learned like all other arts4 ,beginners always set too difficult questions--partly because they are afraid of being suspected of ignorance if they set easy ones1 and partly from not understanding their business4 ,suppose that you want to test the relative physical strength of a score of young men4 ,you do not put a hundredweight down before them1 and tell each to swing it round4 ,if you do1 half of them won't be able to lift it at all1 and only one or two will be able to perform the task4 ,you must give them half a hundredweight1 and see how they manuvre that1 if you want to form any estimate of the muscular strength of each4 ,so1 a practised ,examiner will seek for information respecting the mental vigour and training of candidates from the way in which they deal with questions easy enough to let reason1 memory1 and method have free play4 ,no doubt1 a great deal is to be done by the careful selection of ,examiners1 and by the copious introduction of practical work1 to remove the evils inseparable from examination2 but1 under the best of circumstances1 ,i believe that examination will remain but an imperfect test of knowledge1 and a still more imperfect test of capacity1 while it tells next to nothing about a man's power as an investigator4 ,there is much to be said in favour of restricting the highest degrees in each ,faculty1 to those who have shown evidence of such original power1 by prosecuting a research under the eye of the ,professor in whose province it lies2 or1 at any rate1 under conditions which shall afford satisfactory proof that the work is theirs4 ,the notion may sound revolutionary1 but it is really very old2 for1 ,i take it1 that it lies at the bottom of that presentation of a thesis by the candidate for a doctorate1 which has now1 too often1 become little better than a matter of form4 ,thus far1 ,i have endeavoured to lay before you1 in a too brief and imperfect manner1 my views respecting the teaching half--the ,magistri and ,regentes--of the ,university of the ,future4 ,now let me turn to the learning half--the ,scholares4 ,if the ,universities are to be the sanctuaries of the highest culture of the country1 those who would enter that sanctuary1 must not come with unwashed hands4 ,if the good seed is to yield its hundredfold harvest1 it must not be scattered amidst the stones of ignorance1 or the tares of undisciplined indolence and wantonness4 ,on the contrary1 the soil must have been carefully prepared1 and the ,professor should find that the operations of clod-crushing1 draining1 and weeding1 and even a good deal of planting1 have been done by the ,schoolmaster4 ,that is exactly what the ,professor does not find in any ,university in the three ,kingdoms that ,i can hear of--the reason of which state of things lies in the extremely faulty organisation of the majority of secondary ,schools4 ,students come to the ,universities ill-prepared in classics and mathematics1 not at all prepared in anything else2 and half their time is spent in learning that which they ought to have known when they came4 ,i sometimes hear it said that the ,scottish ,universities differ from the ,english1 in being to a much greater extent places of comparatively elementary education for a younger class of students4 ,but it would seem doubtful if any great difference of this kind really exists2 for a high authority1 himself ,head of an ,english ,college1 has solemnly affirmed that3 8,elementary teaching of youths under twenty is now the only function performed by the ,university20 and that ,colleges are 8boarding schools in which the elements of the learned languages are taught to youths40#f ,this is not the first time that ,i have quoted those remarkable assertions4 ,i should like to engrave them in public view1 for they have not been refuted2 and ,i am convinced that if their import is once clearly apprehended1 they will play no mean part when the question of ,university reorganisation1 with a view to practical measures1 comes on for discussion4 ,you are not responsible for this anomalous state of affairs now2 but1 as you pass into active life and acquire the political influence to which your education and your position should entitle you1 you will become responsible for it1 unless each in his sphere does his best to alter it1 by insisting on the improvement of secondary ,schools4 ,your present responsibility is of another1 though not less serious1 kind4 ,institutions do not make men1 any more than organisation makes life2 and even the ideal ,university we have been dreaming about will be but a superior piece of mechanism1 unless each student strive after the ideal of the ,scholar4 ,and that ideal1 it seems to me1 has never been better embodied than by the great ,poet1 who1 though lapped in luxury1 the favourite of a ,court1 and the idol of his countrymen1 remained through all the length of his honoured years a ,scholar in ,art1 in ,science1 and in ,life4 8,would'st shape a noble life8 ,then cast ,no backward glances towards the past3 ,and though somewhat be lost and gone1 ,yet do thou act as one new-born4 ,what each day needs1 that shalt thou ask2 ,each day will set its proper task4 ,give other's work just share of praise2 ,not of thine own the merits raise4 ,beware no fellow man thou hate3 ,and so in ,god's hands leave thy fate40#g ,,iii4 ,,technical ,,education4 ,any candid observer of the phenomena of modern society will readily admit that bores must be classed among the enemies of the human race2 and a little consideration will probably lead him to the further admission1 that no species of that extensive genus of noxious creatures is more objectionable than the educational bore4 ,convinced as ,i am of the truth of this great social generalisation1 it is not without a certain trepidation that ,i venture to address you on an educational topic4 ,for1 in the course of the last ten years1 to go back no farther1 ,i am afraid to say how often ,i have ventured to speak of education1 from that given in the primary schools to that which is to be had in the universities and medical colleges2 indeed1 the only part of this wide region into which1 as yet1 ,i have not adventured is that into which ,i propose to intrude to-day4 ,thus1 ,i cannot but be aware that ,i am dangerously near becoming the thing which all men fear and fly4 ,but ,i have deliberately elected to run the risk4 ,for when you did me the honour to ask me to address you1 an unexpected circumstance had led me to occupy myself seriously with the question of technical education2 and ,i had acquired the conviction that there are few subjects respecting which it is more important for all classes of the community to have clear and just ideas than this2 while1 certainly1 there is none which is more deserving of attention by the ,working ,men's ,club and ,institute ,union4 ,it is not for me to express an opinion whether the considerations1 which ,i am about to submit to you1 will be proved by experience to be just or not2 but ,i will do my best to make them clear4 ,among the many good things to be found in ,lord ,bacon's works1 none is more full of wisdom than the saying that 8truth more easily comes out of error than out of confusion40 ,clear and consecutive wrong-thinking is the next best thing to right-thinking2 so that1 if ,i succeed in clearing your ideas on this topic1 ,i shall have wasted neither your time nor my own4 8,technical education10 in the sense in which the term is ordinarily used1 and in which ,i am now employing it1 means that sort of education which is specially adapted to the needs of men whose business in life it is to pursue some kind of handicraft2 it is1 in fact1 a fine ,greco-,latin equivalent for what in good vernacular ,english would be called 8the teaching of handicrafts40 ,and probably1 at this stage of our progress1 it may occur to many of you to think of the story of the cobbler and his last1 and to say to yourselves1 though you will be too polite to put the question openly to me1 ,what does the speaker know practically about this matter8 ,what is his handicraft8 ,i think the question is a very proper one1 and unless ,i were prepared to answer it1 ,i hope satisfactorily1 ,i should have chosen some other theme4 ,the fact is1 ,i am1 and have been1 any time these thirty years1 a man who works with his hands--a handicraftsman4 ,i do not say this in the broadly metaphorical sense in which fine gentlemen1 with all the delicacy of ,agag about them1 trip to the hustings about election time1 and protest that they too are working men4 ,i really mean my words to be taken in their direct1 literal1 and straightforward sense4 ,in fact1 if the most nimble-fingered watchmaker among you will come to my workshop1 he may set me to put a watch together1 and ,i will set him to dissect1 say1 a blackbeetle's nerves4 ,i do not wish to vaunt1 but ,i am inclined to think that ,i shall manage my job to his satisfaction sooner than he will do his piece of work to mine4 ,in truth1 anatomy1 which is my handicraft1 is one of the most difficult kinds of mechanical labour1 involving1 as it does1 not only lightness and dexterity of hand1 but sharp eyes and endless patience4 ,and you must not suppose that my particular branch of science is especially distinguished for the demand it makes upon skill in manipulation4 ,a similar requirement is made upon all students of physical science4 ,the astronomer1 the electrician1 the chemist1 the mineralogist1 the botanist1 are constantly called upon to perform manual operations of exceeding delicacy4 ,the progress of all branches of physical science depends upon observation1 or on that artificial observation which is termed experiment1 of one kind or another2 and1 the farther we advance1 the more practical difficulties surround the investigation of the conditions of the problems offered to us2 so that mobile and yet steady hands1 guided by clear vision1 are more and more in request in the workshops of science4 ,indeed1 it has struck me that one of the grounds of that sympathy between the handicraftsmen of this country and the men of science1 by which it has so often been my good fortune to profit1 may1 perhaps1 lie here4 ,you feel and we feel that1 among the so-called learned folks1 we alone are brought into contact with tangible facts in the way that you are4 ,you know well enough that it is one thing to write a history of chairs in general1 or to address a poem to a throne1 or to speculate about the occult powers of the chair of ,st4 ,peter2 and quite another thing to make with your own hands a veritable chair1 that will stand fair and square1 and afford a safe and satisfactory resting-place to a frame of sensitiveness and solidity4 ,so it is with us1 when we look out from our scientific handicrafts upon the doings of our learned brethren1 whose work is untrammelled by anything 8base and mechanical10 as handicrafts used to be called when the world was younger1 and1 in some respects1 less wise than now4 ,we take the greatest interest in their pursuits2 we are edified by their histories and are charmed with their poems1 which sometimes illustrate so remarkably the powers of man's imagination2 some of us admire and even humbly try to follow them in their high philosophical excursions1 though we know the risk of being snubbed by the inquiry whether grovelling dissectors of monkeys and blackbeetles can hope to enter into the empyreal kingdom of speculation4 ,but still we feel that our business is different2 humbler if you will1 though the diminution of dignity is1 perhaps1 compensated by the increase of reality2 and that we1 like you1 have to get our work done in a region where little avails1 if the power of dealing with practical tangible facts is wanting4 ,you know that clever talk touching joinery will not make a chair2 and ,i know that it is of about as much value in the physical sciences4 ,mother ,nature is serenely obdurate to honeyed words2 only those who understand the ways of things1 and can silently and effectually handle them1 get any good out of her4 ,and now1 having1 as ,i hope1 justified my assumption of a place among handicraftsmen1 and put myself right with you as to my qualification1 from practical knowledge1 to speak about technical education1 ,i will proceed to lay before you the results of my experience as a teacher of a handicraft1 and tell you what sort of education ,i should think best adapted for a boy whom one wanted to make a professional anatomist4 ,i should say1 in the first place1 let him have a good ,english elementary education4 ,i do not mean that he shall be able to pass in such and such a standard--that may or may not be an equivalent expression--but that his teaching shall have been such as to have given him command of the common implements of learning and to have created a desire for the things of the understanding4 ,further1 ,i should like him to know the elements of physical science1 and especially of physics and chemistry1 and ,i should take care that this elementary knowledge was real4 ,i should like my aspirant to be able to read a scientific treatise in ,latin1 ,french1 or ,german1 because an enormous amount of anatomical knowledge is locked up in those languages4 ,and especially1 ,i should require some ability to draw--,i do not mean artistically1 for that is a gift which may be cultivated but cannot be learned1 but with fair accuracy4 ,i will not say that everybody can learn even this2 for the negative development of the faculty of drawing in some people is almost miraculous4 ,still everybody1 or almost everybody1 can learn to write2 and1 as writing is a kind of drawing1 ,i suppose that the majority of the people who say they cannot draw1 and give copious evidence of the accuracy of their assertion1 could draw1 after a fashion1 if they tried4 ,and that 8after a fashion0 would be better than nothing for my purposes4 ,above all things1 let my imaginary pupil have preserved the freshness and vigour of youth in his mind as well as his body4 ,the educational abomination of desolation of the present day is the stimulation of young people to work at high pressure by incessant competitive examinations4 ,some wise man 7who probably was not an early riser7 has said of early risers in general1 that they are conceited all the forenoon and stupid all the afternoon4 ,now whether this is true of early risers in the common acceptation of the word or not1 ,i will not pretend to say2 but it is too often true of the unhappy children who are forced to rise too early in their classes4 ,they are conceited all the forenoon of life1 and stupid all its afternoon4 ,the vigour and freshness1 which should have been stored up for the purposes of the hard struggle for existence in practical life1 have been washed out of them by precocious mental debauchery--by book gluttony and lesson bibbing4 ,their faculties are worn out by the strain put upon their callow brains1 and they are demoralised by worthless childish triumphs before the real work of life begins4 ,i have no compassion for sloth1 but youth has more need for intellectual rest than age2 and the cheerfulness1 the tenacity of purpose1 the power of work which make many a successful man what he is1 must often be placed to the credit1 not of his hours of industry1 but to that of his hours of idleness1 in boyhood4 ,even the hardest worker of us all1 if he has to deal with anything above mere details1 will do well1 now and again1 to let his brain lie fallow for a space4 ,the next crop of thought will certainly be all the fuller in the ear and the weeds fewer4 ,this is the sort of education which ,i should like any one who was going to devote himself to my handicraft to undergo4 ,as to knowing anything about anatomy itself1 on the whole ,i would rather he left that alone until he took it up seriously in my laboratory4 ,it is hard work enough to teach1 and ,i should not like to have superadded to that the possible need of unteaching4 ,well1 but1 you will say1 this is ,hamlet with the ,prince of ,denmark left out2 your 8technical education0 is simply a good education1 with more attention to physical science1 to drawing1 and to modern languages1 than is common1 and there is nothing specially technical about it4 ,exactly so2 that remark takes us straight to the heart of what ,i have to say2 which is1 that1 in my judgment1 the preparatory education of the handicraftsman ought to have nothing of what is ordinarily understood by 8technical0 about it4 ,the workshop is the only real school for a handicraft4 ,the education which precedes that of the workshop should be entirely devoted to the strengthening of the body1 the elevation of the moral faculties1 and the cultivation of the intelligence2 and1 especially1 to the imbuing the mind with a broad and clear view of the laws of that natural world with the components of which the handicraftsman will have to deal4 ,and1 the earlier the period of life at which the handicraftsman has to enter into actual practice of his craft1 the more important is it that he should devote the precious hours of preliminary education to things of the mind1 which have no direct and immediate bearing on his branch of industry1 though they lie at the foundation of all realities4 ,now let me apply the lessons ,i have learned from my handicraft to yours4 ,if any of you were obliged to take an apprentice1 ,i suppose you would like to get a good healthy lad1 ready and willing to learn1 handy1 and with his fingers not all thumbs1 as the saying goes4 ,you would like that he should read1 write1 and cipher well2 and1 if you were an intelligent master1 and your trade involved the application of scientific principles1 as so many trades do1 you would like him to know enough of the elementary principles of science to understand what was going on4 ,i suppose that1 in nine trades out of ten1 it would be useful if he could draw2 and many of you must have lamented your inability to find out for yourselves what foreigners are doing or have done4 ,so that some knowledge of ,french and ,german might1 in many cases1 be very desirable4 ,so it appears to me that what you want is pretty much what ,i want2 and the practical question is1 ,how you are to get what you need1 under the actual limitations and conditions of life of handicraftsmen in this country8 ,i think ,i shall have the assent both of the employers of labour and of the employed as to one of these limitations2 which is1 that no scheme of technical education is likely to be seriously entertained which will delay the entrance of boys into working life1 or prevent them from contributing towards their own support1 as early as they do at present4 ,not only do ,i believe that any such scheme could not be carried out1 but ,i doubt its desirableness1 even if it were practicable4 ,the period between childhood and manhood is full of difficulties and dangers1 under the most favourable circumstances2 and1 even among the well-to-do1 who can afford to surround their children with the most favourable conditions1 examples of a career ruined1 before it has well begun1 are but too frequent4 ,moreover1 those who have to live by labour must be shaped to labour early4 ,the colt that is left at grass too long makes but a sorry draught-horse1 though his way of life does not bring him within the reach of artificial temptations4 ,perhaps the most valuable result of all education is the ability to make yourself do the thing you have to do1 when it ought to be done1 whether you like it or not2 it is the first lesson that ought to be learned2 and1 however early a man's training begins1 it is probably the last lesson that he learns thoroughly4 ,there is another reason1 to which ,i have already adverted1 and which ,i would reiterate1 why any extension of the time devoted to ordinary school-work is undesirable4 ,in the newly awakened zeal for education1 we run some risk of forgetting the truth that while under-instruction is a bad thing1 over-instruction may possibly be a worse4 ,success in any kind of practical life is not dependent solely1 or indeed chiefly1 upon knowledge4 ,even in the learned professions1 knowledge1 alone1 is of less consequence than people are apt to suppose4 ,and1 if much expenditure of bodily energy is involved in the day's work1 mere knowledge is of still less importance when weighed against the probable cost of its acquirement4 ,to do a fair day's work with his hands1 a man needs1 above all things1 health1 strength1 and the patience and cheerfulness which1 if they do not always accompany these blessings1 can hardly in the nature of things exist without them2 to which we must add honesty of purpose and a pride in doing what is done well4 ,a good handicraftsman can get on very well without genius1 but he will fare badly without a reasonable share of that which is a more useful possession for workaday life1 namely1 mother-wit2 and he will be all the better for a real knowledge1 however limited1 of the ordinary laws of nature1 and especially of those which apply to his own business4 ,instruction carried so far as to help the scholar to turn his store of mother-wit to account1 to acquire a fair amount of sound elementary knowledge1 and to use his hands and eyes2 while leaving him fresh1 vigorous1 and with a sense of the dignity of his own calling1 whatever it may be1 if fairly and honestly pursued1 cannot fail to be of invaluable service to all those who come under its influence4 ,but1 on the other hand1 if school instruction is carried so far as to encourage bookishness2 if the ambition of the scholar is directed1 not to the gaining of knowledge1 but to the being able to pass examinations successfully2 especially if encouragement is given to the mischievous delusion that brainwork is1 in itself1 and apart from its quality1 a nobler or more respectable thing than handiwork--such education may be a deadly mischief to the workman1 and lead to the rapid ruin of the industries it is intended to serve4 ,i know that ,i am expressing the opinion of some of the largest as well as the most enlightened employers of labour1 when ,i say that there is a real danger that1 from the extreme of no education1 we may run to the other extreme of over-education of handicraftsmen4 ,and ,i apprehend that what is true for the ordinary hand-worker is true for the foreman4 ,activity1 probity1 knowledge of men1 ready mother-wit1 supplemented by a good knowledge of the general principles involved in his business1 are the making of a good foreman4 ,if he possess these qualities1 no amount of learning will fit him better for his position2 while the course of life and the habit of mind required for the attainment of such learning may1 in various direct and indirect ways1 act as direct disqualifications for it4 ,keeping in mind1 then1 that the two things to be avoided are1 the delay of the entrance of boys into practical life1 and the substitution of exhausted book-worms for shrewd1 handy men1 in our works and factories1 let us consider what may be wisely and safely attempted in the way of improving the education of the handicraftsman4 ,first1 ,i look to the elementary schools now happily established all over the country4 ,i am not going to criticise or find fault with them2 on the contrary1 their establishment seems to me to be the most important and the most beneficial result of the corporate action of the people in our day4 ,a great deal is said of ,british interests just now1 but1 depend upon it1 that no ,eastern difficulty needs our intervention as a nation so seriously1 as the putting down both the ,bashi-,bazouks of ignorance and the ,cossacks of sectarianism at home4 ,what has already been achieved in these directions is a great thing2 you must have lived some time to know how great4 ,an education1 better in its processes1 better in its substance1 than that which was accessible to the great majority of well-to-do ,britons a quarter of a century ago1 is now obtainable by every child in the land4 ,let any man of my age go into an ordinary elementary school1 and1 unless he was unusually fortunate in his youth1 he will tell you that the educational method1 the intelligence1 patience1 and good temper on the teacher's part1 which are now at the disposal of the veriest waifs and wastrels of society1 are things of which he had no experience in those costly middle-class schools1 which were so ingeniously contrived as to combine all the evils and shortcomings of the great public schools with none of their advantages4 ,many a man1 whose so-called education cost a good deal of valuable money and occupied many a year of invaluable time1 leaves the inspection of a well-ordered elementary school devoutly wishing that1 in his young days1 he had had the chance of being as well taught as these boys and girls are4 ,but while1 in view of such an advance in general education1 ,i willingly obey the natural impulse to be thankful1 ,i am not willing altogether to rest4 ,i want to see instruction in elementary science and in art more thoroughly incorporated in the educational system4 ,at present1 it is being administered by driblets1 as if it were a potent medicine1 8a few drops to be taken occasionally in a teaspoon40 ,every year ,i notice that that earnest and untiring friend of yours and of mine1 ,sir ,john ,lubbock1 stirs up the ,government of the day in the ,house of ,commons on this subject2 and also that1 every year1 he1 and the few members of the ,house of ,commons1 such as ,mr4 ,playfair1 who sympathise with him1 are met with expressions of warm admiration for science in general1 and reasons at large for doing nothing in particular4 ,but now that ,mr4 ,forster1 to whom the education of the country owes so much1 has announced his conversion to the right faith1 ,i begin to hope that1 sooner or later1 things will mend4 ,i have given what ,i believe to be a good reason for the assumption1 that the keeping at school of boys1 who are to be handicraftsmen1 beyond the age of thirteen or fourteen is neither practicable nor desirable2 and1 as it is quite certain1 that1 with justice to other and no less important branches of education1 nothing more than the rudiments of science and art teaching can be introduced into elementary schools1 we must seek elsewhere for a supplementary training in these subjects1 and1 if need be1 in foreign languages1 which may go on after the workman's life has begun4 ,the means of acquiring the scientific and artistic part of this training already exists in full working order1 in the first place1 in the classes of the ,science and ,art ,department1 which are1 for the most part1 held in the evening1 so as to be accessible to all who choose to avail themselves of them after working hours4 ,the great advantage of these classes is that they bring the means of instruction to the doors of the factories and workshops2 that they are no artificial creations1 but by their very existence prove the desire of the people for them2 and finally1 that they admit of indefinite development in proportion as they are wanted4 ,i have often expressed the opinion1 and ,i repeat it here1 that1 during the eighteen years they have been in existence1 these classes have done incalculable good2 and ,i can say1 of my own knowledge1 that the ,department spares no pains and trouble in trying to increase their usefulness and ensure the soundness of their work4 ,no one knows better than my friend ,colonel ,donnelly1 to whose clear views and great administrative abilities so much of the successful working of the science classes is due1 that there is much to be done before the system can be said to be thoroughly satisfactory4 ,the instruction given needs to be made more systematic and especially more practical2 the teachers are of very unequal excellence1 and not a few stand much in need of instruction themselves1 not only in the subjects which they teach1 but in the objects for which they teach4 ,i daresay you have heard of that proceeding1 reprobated by all true sportsmen1 which is called 8shooting for the pot40 ,well1 there is such a thing as 8teaching for the pot0--teaching1 that is1 not that your scholar may know1 but that he may count for payment among those who pass the examination2 and there are some teachers1 happily not many1 who have yet to learn that the examiners of the ,department regard them as poachers of the worst description4 ,without presuming in any way to speak in the name of the ,department1 ,i think ,i may say1 as a matter which has come under my own observation1 that it is doing its best to meet all these difficulties4 ,it systematically promotes practical instruction in the classes2 it affords facilities to teachers who desire to learn their business thoroughly2 and it is always ready to aid in the suppression of pot-teaching4 ,all this is1 as you may imagine1 highly satisfactory to me4 ,i see that spread of scientific education1 about which ,i have so often permitted myself to worry the public1 become1 for all practical purposes1 an accomplished fact4 ,grateful as ,i am for all that is now being done1 in the same direction1 in our higher schools and universities1 ,i have ceased to have any anxiety about the wealthier classes4 ,scientific knowledge is spreading by what the alchemists called a 8distillatio per ascensum20 and nothing now can prevent it from continuing to distil upwards and permeate ,english society1 until1 in the remote future1 there shall be no member of the legislature who does not know as much of science as an elementary school-boy2 and even the heads of houses in our venerable seats of learning shall acknowledge that natural science is not merely a sort of ,university back-door through which inferior men may get at their degrees4 ,perhaps this apocalyptic vision is a little wild2 and ,i feel ,i ought to ask pardon for an outbreak of enthusiasm1 which1 ,i assure you1 is not my commonest failing4 ,i have said that the ,government is already doing a great deal in aid of that kind of technical education for handicraftsmen which1 to my mind1 is alone worth seeking4 ,perhaps it is doing as much as it ought to do1 even in this direction4 ,certainly there is another kind of help of the most important character1 for which we may look elsewhere than to the ,government4 ,the great mass of mankind have neither the liking1 nor the aptitude1 for either literary1 or scientific1 or artistic pursuits2 nor1 indeed1 for excellence of any sort4 ,their ambition is to go through life with moderate exertion and a fair share of ease1 doing common things in a common way4 ,and a great blessing and comfort it is that the majority of men are of this mind2 for the majority of things to be done are common things1 and are quite well enough done when commonly done4 ,the great end of life is not knowledge but action4 ,what men need is1 as much knowledge as they can assimilate and organise into a basis for action2 give them more and it may become injurious4 ,one knows people who are as heavy and stupid from undigested learning as others are from over-fulness of meat and drink4 ,but a small percentage of the population is born with that most excellent quality1 a desire for excellence1 or with special aptitudes of some sort or another2 ,mr4 ,galton tells us that not more than one in four thousand may be expected to attain distinction1 and not more than one in a million some share of that intensity of instinctive aptitude1 that burning thirst for excellence1 which is called genius4 ,now1 the most important object of all educational schemes is to catch these exceptional people1 and turn them to account for the good of society4 ,no man can say where they will crop up2 like their opposites1 the fools and knaves1 they appear sometimes in the palace1 and sometimes in the hovel2 but the great thing to be aimed at1 ,i was almost going to say the most important end of all social arrangements1 is to keep these glorious sports of ,nature from being either corrupted by luxury or starved by poverty1 and to put them into the position in which they can do the work for which they are specially fitted4 ,thus1 if a lad in an elementary school showed signs of special capacity1 ,i would try to provide him with the means of continuing his education after his daily working life had begun2 if1 in the evening classes1 he developed special capabilities in the direction of science or of drawing1 ,i would try to secure him an apprenticeship to some trade in which those powers would have applicability4 ,or1 if he chose to become a teacher1 he should have the chance of so doing4 ,finally1 to the lad of genius1 the one in a million1 ,i would make accessible the highest and most complete training the country could afford4 ,whatever that might cost1 depend upon it the investment would be a good one4 ,i weigh my words when ,i say that if the nation could purchase a potential ,watt1 or ,davy1 or ,faraday1 at the cost of a hundred thousand pounds down1 he would be dirt-cheap at the money4 ,it is a mere commonplace and everyday piece of knowledge1 that what these three men did has produced untold millions of wealth1 in the narrowest economical sense of the word4 ,therefore1 as the sum and crown of what is to be done for technical education1 ,i look to the provision of a machinery for winnowing out the capacities and giving them scope4 ,when ,i was a member of the ,london ,school ,board1 ,i said1 in the course of a speech1 that our business was to provide a ladder1 reaching from the gutter to the university1 along which every child in the three kingdoms should have the chance of climbing as far as he was fit to go4 ,this phrase was so much bandied about at the time1 that1 to say truth1 ,i am rather tired of it2 but ,i know of no other which so fully expresses my belief1 not only about education in general1 but about technical education in particular4 ,the essential foundation of all the organisation needed for the promotion of education among handicraftsmen will1 ,i believe1 exist in this country1 when every working lad can feel that society has done as much as lies in its power to remove all needless and artificial obstacles from his path2 that there is no barrier1 except such as exists in the nature of things1 between himself and whatever place in the social organisation he is fitted to fill2 and1 more than this1 that1 if he has capacity and industry1 a hand is held out to help him along any path which is wisely and honestly chosen4 ,i have endeavoured to point out to you that a great deal of such an organisation already exists2 and ,i am glad to be able to add that there is a good prospect that what is wanting will1 before long1 be supplemented4 ,those powerful and wealthy societies1 the livery companies of the ,city of ,london1 remembering that they are the heirs and representatives of the trade guilds of the ,middle ,ages1 are interesting themselves in the question4 ,so far back as #ahgb the ,society of ,arts organised a system of instruction in the technology of arts and manufactures1 for persons actually employed in factories and workshops1 who desired to extend and improve their knowledge of the theory and practice of their particular avocations2#h and a considerable subsidy1 in aid of the efforts of the ,society1 was liberally granted by the ,clothworkers' ,company4 ,we have here the hopeful commencement of a rational organisation for the promotion of excellence among handicraftsmen4 ,quite recently1 other of the livery companies have determined upon giving their powerful1 and1 indeed1 almost boundless1 aid to the improvement of the teaching of handicrafts4 ,they have already gone so far as to appoint a committee to act for them2 and ,i betray no confidence in adding that1 some time since1 the committee sought the advice and assistance of several persons1 myself among the number4 ,of course ,i cannot tell you what may be the result of the deliberations of the committee2 but we may all fairly hope that1 before long1 steps which will have a weighty and a lasting influence on the growth and spread of sound and thorough teaching among the handicraftsmen#i of this country will be taken by the livery companies of ,london4 ,this hope has been fully justified by the establishment of the ,cowper ,street ,schools1 and that of the ,central ,institution of the ,city and ,guilds of ,london ,institute4 ,september #ahha4 ,,iv4 ,,on ,,elementary ,,instruction ,,in ,,physiology4 ,the chief ground upon which ,i venture to recommend that the teaching of elementary physiology should form an essential part of any organised course of instruction in matters pertaining to domestic economy1 is1 that a knowledge of even the elements of this subject supplies those conceptions of the constitution and mode of action of the living body1 and of the nature of health and disease1 which prepare the mind to receive instruction from sanitary science4 ,it is1 ,i think1 eminently desirable that the hygienist and the physician should find something in the public mind to which they can appeal2 some little stock of universally acknowledged truths1 which may serve as a foundation for their warnings1 and predispose towards an intelligent obedience to their recommendations4 ,listening to ordinary talk about health1 disease1 and death1 one is often led to entertain a doubt whether the speakers believe that the course of natural causation runs as smoothly in the human body as elsewhere4 ,indications are too often obvious of a strong1 though perhaps an unavowed and half unconscious1 under-current of opinion that the phenomena of life are not only widely different1 in their superficial characters and in their practical importance1 from other natural events1 but that they do not follow in that definite order which characterises the succession of all other occurrences1 and the statement of which we call a law of nature4 ,hence1 ,i think1 arises the want of heartiness of belief in the value of knowledge respecting the laws of health and disease1 and of the foresight and care to which knowledge is the essential preliminary1 which is so often noticeable2 and a corresponding laxity and carelessness in practice1 the results of which are too frequently lamentable4 ,it is said that among the many religious sects of ,russia1 there is one which holds that all disease is brought about by the direct and special interference of the ,deity1 and which1 therefore1 looks with repugnance upon both preventive and curative measures as alike blasphemous interferences with the will of ,god4 ,among ourselves1 the 8,peculiar ,people0 are1 ,i believe1 the only persons who hold the like doctrine in its integrity1 and carry it out with logical rigour4 ,but many of us are old enough to recollect that the administration of chloroform in assuagement of the pangs of childbirth was1 at its introduction1 strenuously resisted upon similar grounds4 ,i am not sure that the feeling1 of which the doctrine to which ,i have referred is the full expression1 does not lie at the bottom of the minds of a great many people who yet would vigorously object to give a verbal assent to the doctrine itself4 ,however this may be1 the main point is that sufficient knowledge has now been acquired of vital phenomena1 to justify the assertion1 that the notion1 that there is anything exceptional about these phenomena1 receives not a particle of support from any known fact4 ,on the contrary1 there is a vast and an increasing mass of evidence that birth and death1 health and disease1 are as much parts of the ordinary stream of events as the rising and setting of the sun1 or the changes of the moon2 and that the living body is a mechanism1 the proper working of which we term health2 its disturbance1 disease2 its stoppage1 death4 ,the activity of this mechanism is dependent upon many and complicated conditions1 some of which are hopelessly beyond our control1 while others are readily accessible1 and are capable of being indefinitely modified by our own actions4 ,the business of the hygienist and of the physician is to know the range of these modifiable conditions1 and how to influence them towards the maintenance of health and the prolongation of life2 the business of the general public is to give an intelligent assent1 and a ready obedience based upon that assent1 to the rules laid down for their guidance by such experts4 ,but an intelligent assent is an assent based upon knowledge1 and the knowledge which is here in question means an acquaintance with the elements of physiology4 ,it is not difficult to acquire such knowledge4 ,what is true1 to a certain extent1 of all the physical sciences1 is eminently characteristic of physiology--the difficulty of the subject begins beyond the stage of elementary knowledge1 and increases with every stage of progress4 ,while the most highly trained and the best furnished intellect may find all its resources insufficient1 when it strives to reach the heights and penetrate into the depths of the problems of physiology1 the elementary and fundamental truths can be made clear to a child4 ,no one can have any difficulty in comprehending the mechanism of circulation or respiration2 or the general mode of operation of the organ of vision2 though the unravelling of all the minuti of these processes1 may1 for the present1 baffle the conjoined attacks of the most accomplished physicists1 chemists1 and mathematicians4 ,to know the anatomy of the human body1 with even an approximation to thoroughness1 is the work of a life2 but as much as is needed for a sound comprehension of elementary physiological truths1 may be learned in a week4 ,a knowledge of the elements of physiology is not only easy of acquirement1 but it may be made a real and practical acquaintance with the facts1 as far as it goes4 ,the subject of study is always at hand1 in oneself4 ,the principal constituents of the skeleton1 and the changes of form of contracting muscles1 may be felt through one's own skin4 ,the beating of one's heart1 and its connection with the pulse1 may be noted2 the influence of the valves of one's own veins may be shown2 the movements of respiration may be observed2 while the wonderful phenomena of sensation afford an endless field for curious and interesting self-study4 ,the prick of a needle will yield1 in a drop of one's own blood1 material for microscopic observation of phenomena which lie at the foundation of all biological conceptions2 and a cold1 with its concomitant coughing and sneezing1 may prove the sweet uses of adversity by helping one to a clear conception of what is meant by 8reflex action40 ,of course there is a limit to this physiological self-examination4 ,but there is so close a solidarity between ourselves and our poor relations of the animal world1 that our inaccessible inward parts may be supplemented by theirs4 ,a comparative anatomist knows that a sheep's heart and lungs1 or eye1 must not be confounded with those of a man2 but1 so far as the comprehension of the elementary facts of the physiology of circulation1 of respiration1 and of vision goes1 the one furnishes the needful anatomical data as well as the other4 ,thus1 it is quite possible to give instruction in elementary physiology in such a manner as1 not only to confer knowledge1 which1 for the reason ,i have mentioned1 is useful in itself2 but to serve the purposes of a training in accurate observation1 and in the methods of reasoning of physical science4 ,but that is an advantage which ,i mention only incidentally1 as the present ,conference does not deal with education in the ordinary sense of the word4 ,it will not be suspected that ,i wish to make physiologists of all the world4 ,it would be as reasonable to accuse an advocate of the 8three ,r's0 of a desire to make an orator1 an author1 and a mathematician of everybody4 ,a stumbling reader1 a pot-hook writer1 and an arithmetician who has not got beyond the rule of three1 is not a person of brilliant acquirements2 but the difference between such a member of society and one who can neither read1 write1 nor cipher is almost inexpressible2 and no one now-a-days doubts the value of instruction1 even if it goes no farther4 ,the saying that a little knowledge is a dangerous thing is1 to my mind1 a very dangerous adage4 ,if knowledge is real and genuine1 ,i do not believe that it is other than a very valuable possession1 however infinitesimal its quantity may be4 ,indeed1 if a little knowledge is dangerous1 where is the man who has so much as to be out of danger8 ,if ,william ,harvey's life-long labours had revealed to him a tenth part of that which may be made sound and real knowledge to our boys and girls1 he would not only have been what he was1 the greatest physiologist of his age1 but he would have loomed upon the seventeenth century as a sort of intellectual portent4 ,our 8little knowledge0 would have been to him a great1 astounding1 unlooked-for vision of scientific truth4 ,i really see no harm which can come of giving our children a little knowledge of physiology4 ,but then1 as ,i have said1 the instruction must be real1 based upon observation1 eked out by good explanatory diagrams and models1 and conveyed by a teacher whose own knowledge has been acquired by a study of the facts2 and not the mere catechismal parrot-work which too often usurps the place of elementary teaching4 ,it is1 ,i hope1 unnecessary for me to give a formal contradiction to the silly fiction1 which is assiduously circulated by fanatics who not only ought to know1 but do know1 that their assertions are untrue1 that ,i have advocated the introduction of that experimental discipline which is absolutely indispensable to the professed physiologist1 into elementary teaching4 ,but while ,i should object to any experimentation which can justly be called painful1 for the purpose of elementary instruction2 and1 while1 as a member of a late ,royal ,commission1 ,i gladly did my best to prevent the infliction of needless pain1 for any purpose2 ,i think it is my duty to take this opportunity of expressing my regret at a condition of the law which permits a boy to troll for pike1 or set lines with live frog bait1 for idle amusement2 and1 at the same time1 lays the teacher of that boy open to the penalty of fine and imprisonment1 if he uses the same animal for the purpose of exhibiting one of the most beautiful and instructive of physiological spectacles1 the circulation in the web of the foot4 ,no one could undertake to affirm that a frog is not inconvenienced by being wrapped up in a wet rag1 and having his toes tied out2 and it cannot be denied that inconvenience is a sort of pain4 ,but you must not inflict the least pain on a vertebrated animal for scientific purposes 7though you may do a good deal in that way for gain or for sport7 without due licence of the ,secretary of ,state for the ,home ,department1 granted under the authority of the ,vivisection ,act4 ,so it comes about1 that1 in this present year of grace #ahgg1 two persons may be charged with cruelty to animals4 ,one has impaled a frog1 and suffered the creature to writhe about in that condition for hours2 the other has pained the animal no more than one of us would be pained by tying strings round his fingers1 and keeping him in the position of a hydropathic patient4 ,the first offender says1 8,i did it because ,i find fishing very amusing10 and the magistrate bids him depart in peace2 nay1 probably wishes him good sport4 ,the second pleads1 8,i wanted to impress a scientific truth1 with a distinctness attainable in no other way1 on the minds of my scholars10 and the magistrate fines him five pounds4 ,i cannot but think that this is an anomalous and not wholly creditable state of things4 ,v4 ,,joseph ,,priestley4 ,if the man to perpetuate whose memory we have this day raised a statue had been asked on what part of his busy life's work he set the highest value1 he would undoubtedly have pointed to his voluminous contributions to theology4 ,in season and out of season1 he was the steadfast champion of that hypothesis respecting the ,divine nature which is termed ,unitarianism by its friends and ,socinianism by its foes4 ,regardless of odds1 he was ready to do battle with all comers in that cause2 and if no adversaries entered the lists1 he would sally forth to seek them4 ,to this1 his highest ideal of duty1 ,joseph ,priestley sacrificed the vulgar prizes of life1 which1 assuredly1 were within easy reach of a man of his singular energy and varied abilities4 ,for this object1 he put aside1 as of secondary importance1 those scientific investigations which he loved so well1 and in which he showed himself so competent to enlarge the boundaries of natural knowledge and to win fame4 ,in this cause1 he not only cheerfully suffered obloquy from the bigoted and the unthinking1 and came within sight of martyrdom2 but bore with that which is much harder to be borne than all these1 the unfeigned astonishment and hardly disguised contempt of a brilliant society1 composed of men whose sympathy and esteem must have been most dear to him1 and to whom it was simply incomprehensible that a philosopher should seriously occupy himself with any form of ,christianity4 ,it appears to me that the man who1 setting before himself such an ideal of life1 acted up to it consistently1 is worthy of the deepest respect1 whatever opinion may be entertained as to the real value of the tenets which he so zealously propagated and defended4 ,but ,i am sure that ,i speak not only for myself1 but for all this assemblage1 when ,i say that our purpose to-day is to do honour1 not to ,priestley1 the ,unitarian divine1 but to ,priestley1 the fearless defender of rational freedom in thought and in action3 to ,priestley1 the philosophic thinker2 to that ,priestley who held a foremost place among 8the swift runners who hand over the lamp of life10#aj and transmit from one generation to another the fire kindled1 in the childhood of the world1 at the ,promethean altar of ,science4 ,the main incidents of ,priestley's life are so well known that ,i need dwell upon them at no great length4 ,born in #agcc1 at ,fieldhead1 near ,leeds1 and brought up among ,calvinists of the straitest orthodoxy1 the boy's striking natural ability led to his being devoted to the profession of a minister of religion2 and1 in #ageb1 he was sent to the ,dissenting ,academy at ,daventry--an institution which authority left undisturbed1 though its existence contravened the law4 ,the teachers under whose instruction and influence the young man came at ,daventry1 carried out to the letter the injunction to 8try all things3 hold fast that which is good10 and encouraged the discussion of every imaginable proposition with complete freedom1 the leading professors taking opposite sides2 a discipline which1 admirable as it may be from a purely scientific point of view1 would seem to be calculated to make acute1 rather than sound1 divines4 ,priestley tells us1 in his 8,autobiography10 that he generally found himself on the unorthodox side3 and1 as he grew older1 and his faculties attained their maturity1 this native tendency towards heterodoxy grew with his growth and strengthened with his strength4 ,he passed from ,calvinism to ,arianism2 and finally1 in middle life1 landed in that very broad form of ,unitarianism1 by which his craving after a credible and consistent theory of things was satisfied4 ,on leaving ,daventry1 ,priestley became minister of a congregation1 first at ,needham ,market1 and secondly at ,nantwich2 but whether on account of his heterodox opinions1 or of the stuttering which impeded his expression of them in the pulpit1 little success attended his efforts in this capacity4 ,in #agfa1 a career much more suited to his abilities became open to him4 ,he was appointed 8tutor in the languages0 in the ,dissenting ,academy at ,warrington1 in which capacity1 besides giving three courses of lectures1 he taught ,latin1 ,greek1 ,french1 and ,italian1 and read lectures on the ,theory of ,language and ,universal ,grammar1 on ,oratory1 ,philosophical ,criticism1 and ,civil law4 ,and it is interesting to observe that1 as a teacher1 he encouraged and cherished in those whom he instructed1 the freedom which he had enjoyed1 in his own student days1 at ,daventry4 ,one of his pupils tells us that1 8,at the conclusion of his lecture1 he always encouraged his students to express their sentiments relative to the subject of it1 and to urge any objections to what he had delivered1 without reserve4 ,it pleased him when any one commenced such a conversation4 ,in order to excite the freest discussion1 he occasionally invited the students to drink tea with him1 in order to canvass the subjects of his lectures4 ,i do not recollect that he ever showed the least displeasure at the strongest objections that were made to what he delivered1 but ,i distinctly remember the smile of approbation with which he usually received them3 nor did he fail to point out1 in a very encouraging manner1 the ingenuity or force of any remarks that were made1 when they merited these characters4 ,his object1 as well as ,dr4 ,aikin's1 was to engage the students to examine and decide for themselves1 uninfluenced by the sentiments of any other persons40#aa ,it would be difficult to give a better description of a model teacher than that conveyed in these words4 ,from his earliest days1 ,priestley had shown a strong bent towards the study of nature2 and his brother ,timothy tells us that the boy put spiders into bottles1 to see how long they would live in the same air--a curious anticipation of the investigations of his later years4 ,at ,nantwich1 where he set up a school1 ,priestley informs us that he bought an air pump1 an electrical machine1 and other instruments1 in the use of which he instructed his scholars4 ,but he does not seem to have devoted himself seriously to physical science until #agff1 when he had the great good fortune to meet ,benjamin ,franklin1 whose friendship he ever afterwards enjoyed4 ,encouraged by ,franklin1 he wrote a 8,history of ,electricity10 which was published in #agfg1 and appears to have met with considerable success4 ,in the same year1 ,priestley left ,warrington to become the minister of a congregation at ,leeds2 and1 here1 happening to live next door to a public brewery1 as he says1 8,i1 at first1 amused myself with making experiments on the fixed air which ,i found ready-made in the process of fermentation4 ,when ,i removed from that house ,i was under the necessity of making fixed air for myself2 and one experiment leading to another1 as ,i have distinctly and faithfully noted in my various publications on the subject1 ,i by degrees contrived a convenient apparatus for the purpose1 but of the cheapest kind4 8,when ,i began these experiments ,i knew very little of chemistry1 and had1 in a manner1 no idea on the subject before ,i attended a course of chemical lectures1 delivered in the ,academy at ,warrington1 by ,dr4 ,turner of ,liverpool4 ,but ,i have often thought that1 upon the whole1 this circumstance was no disadvantage to me2 as1 in this situation1 ,i was led to devise an apparatus and processes of my own1 adapted to my peculiar views2 whereas1 if ,i had been previously accustomed to the usual chemical processes1 ,i should not have so easily thought of any other1 and without new modes of operation1 ,i should hardly have discovered anything materially new40#ab ,the first outcome of ,priestley's chemical work1 published in #aggb1 was of a very practical character4 ,he discovered the way of impregnating water with an excess of 8fixed air10 or carbonic acid1 and thereby producing what we now know as 8soda water0--a service to naturally1 and still more to artificially1 thirsty souls1 which those whose parched throats and hot heads are cooled by morning draughts of that beverage1 cannot too gratefully acknowledge4 ,in the same year1 ,priestley communicated the extensive series of observations which his industry and ingenuity had accumulated1 in the course of four years1 to the ,royal ,society1 under the title of 8,observations on ,different ,kinds of ,air0--a memoir which was justly regarded of so much merit and importance1 that the ,society at once conferred upon the author the highest distinction in their power1 by awarding him the ,copley ,medal4 ,in #agga a proposal was made to ,priestley to accompany ,captain ,cook in his second voyage to the ,south ,seas4 ,he accepted it1 and his congregation agreed to pay an assistant to supply his place during his absence4 ,but the appointment lay in the hands of the ,board of ,longitude1 of which certain clergymen were members2 and whether these worthy ecclesiastics feared that ,priestley's presence among the ship's company might expose his ,majesty's ,sloop ,resolution to the fate which aforetime befell a certain ship that went from ,joppa to ,tarshish2 or whether they were alarmed lest a ,socinian should undermine that piety which1 in the days of ,commodore ,trunnion1 so strikingly characterised sailors1 does not appear2 but1 at any rate1 they objected to ,priestley 8on account of his religious principles10 and appointed the two ,forsters1 whose 8religious principles10 if they had been known to these well-meaning but not far-sighted persons1 would probably have surprised them4 ,in #aggb another proposal was made to ,priestley4 ,lord ,shelburne1 desiring a 8literary companion10 had been brought into communication with ,priestley by the good offices of a friend of both1 ,dr4 ,price2 and offered him the nominal post of librarian1 with a good house and appointments1 and an annuity in case of the termination of the engagement4 ,priestley accepted the offer1 and remained with ,lord ,shelburne for seven years1 sometimes residing at ,calne1 sometimes travelling abroad with the ,earl4 ,why the connection terminated has never been exactly known2 but it is certain that ,lord ,shelburne behaved with the utmost consideration and kindness towards ,priestley2 that he fulfilled his engagements to the letter2 and that1 at a later period1 he expressed a desire that ,priestley should return to his old footing in his house4 ,probably enough1 the politician1 aspiring to the highest offices in the state1 may have found the position of the protector of a man who was being denounced all over the country as an infidel and an atheist somewhat embarrassing4 ,in fact1 a passage in ,priestley's 8,autobiography0 on the occasion of the publication of his 8,disquisitions relating to ,matter and ,spirit10 which took place in #aggg1 indicates pretty clearly the state of the case3-- 87#abf7 ,it being probable that this publication would be unpopular1 and might be the means of bringing odium on my patron1 several attempts were made by his friends1 though none by himself1 to dissuade me from persisting in it4 ,but being1 as ,i thought1 engaged in the cause of important truth1 ,i proceeded without regard to any consequences1 assuring them that this publication should not be injurious to his lordship40 ,it is not unreasonable to suppose that his lordship1 as a keen1 practical man of the world1 did not derive much satisfaction from this assurance4 ,the 8evident marks of dissatisfaction0 which ,priestley says he first perceived in his patron in #aggh1 may well have arisen from the peer's not unnatural uneasiness as to what his domesticated1 but not tamed1 philosopher might write next1 and what storm might thereby be brought down on his own head2 and it speaks very highly for ,lord ,shelburne's delicacy that1 in the midst of such perplexities1 he made not the least attempt to interfere with ,priestley's freedom of action4 ,in #aghj1 however1 he intimated to ,dr4 ,price that he should be glad to establish ,priestley on his ,irish estates3 the suggestion was interpreted1 as ,lord ,shelburne probably intended it should be1 and ,priestley left him1 the annuity of #aej a year1 which had been promised in view of such a contingency1 being punctually paid4 ,after leaving ,calne1 ,priestley spent some little time in ,london1 and then1 having settled in ,birmingham at the desire of his brother-in-law1 he was soon invited to become the minister of a large congregation4 ,this settlement ,priestley considered1 at the time1 to be 8the happiest event of his life40 ,and well he might think so2 for it gave him competence and leisure2 placed him within reach of the best makers of apparatus of the day2 made him a member of that remarkable 8,lunar ,society10 at whose meetings he could exchange thoughts with such men as ,watt1 ,wedgewood1 ,darwin1 and ,boulton2 and threw open to him the pleasant house of the ,galtons of ,barr1 where these men1 and others of less note1 formed a society of exceptional charm and intelligence4#ac ,but these halcyon days were ended by a bitter storm4 ,the ,french ,revolution broke out4 ,an electric shock ran through the nations2 whatever there was of corrupt and retrograde1 and1 at the same time1 a great deal of what there was of best and noblest1 in ,european society shuddered at the outburst of long-pent-up social fires4 ,men's feelings were excited in a way that we1 in this generation1 can hardly comprehend4 ,party wrath and virulence were expressed in a manner unparalleled1 and it is to be hoped impossible1 in our times2 and ,priestley and his friends were held up to public scorn1 even in ,parliament1 as fomenters of sedition4 ,a 8,church-and-,king0 cry was raised against the ,liberal ,dissenters2 and1 in ,birmingham1 it was intensified and specially directed towards ,priestley by a local controversy1 in which he had engaged with his usual vigour4 ,in #agia1 the celebration of the second anniversary of the taking of the ,bastille by a public dinner1 with which ,priestley had nothing whatever to do1 gave the signal to the loyal and pious mob1 who1 unchecked1 and indeed to some extent encouraged1 by those who were responsible for order1 had the town at their mercy for three days4 ,the chapels and houses of the leading ,dissenters were wrecked1 and ,priestley and his family had to fly for their lives1 leaving library1 apparatus1 papers1 and all their possessions1 a prey to the flames4 ,priestley never returned to ,birmingham4 ,he bore the outrages and losses inflicted upon him with extreme patience and sweetness1#ad and betook himself to ,london4 ,but even his scientific colleagues gave him a cold shoulder2 and though he was elected minister of a congregation at ,hackney1 he felt his position to be insecure1 and finally determined on emigrating to the ,united ,states4 ,he landed in ,america in #agid2 lived quietly with his sons at ,northumberland1 in ,pennsylvania1 where his posterity still flourish2 and1 clear-headed and busy to the last1 died on the #fth of ,february #ahjd4 ,such were the conditions under which ,joseph ,priestley did the work which lay before him1 and then1 as the ,norse ,sagas say1 went out of the story4 ,the work itself was of the most varied kind4 ,no human interest was without its attraction for ,priestley1 and few men have ever had so many irons in the fire at once2 but1 though he may have burned his fingers a little1 very few who have tried that operation have burned their fingers so little4 ,he made admirable discoveries in science2 his philosophical treatises are still well worth reading2 his political works are full of insight and replete with the spirit of freedom2 and while all these sparks flew off from his anvil1 the controversial hammer rained a hail of blows on orthodox priest and bishop4 ,while thus engaged1 the kindly1 cheerful doctor felt no more wrath or uncharitableness towards his opponents than a smith does towards his iron4 ,but if the iron could only speak6--and the priests and bishops took the point of view of the iron4 ,no doubt what ,priestley's friends repeatedly urged upon him--that he would have escaped the heavier trials of his life and done more for the advancement of knowledge1 if he had confined himself to his scientific pursuits and let his fellow-men go their way--was true4 ,but it seems to have been ,priestley's feeling that he was a man and a citizen before he was a philosopher1 and that the duties of the two former positions are at least as imperative as those of the latter4 ,moreover1 there are men 7and ,i think ,priestley was one of them7 to whom the satisfaction of throwing down a triumphant fallacy is as great as that which attends the discovery of a new truth2 who feel better satisfied with the government of the world1 when they have been helping ,providence by knocking an imposture on the head2 and who care even more for freedom of thought than for mere advance of knowledge4 ,these men are the ,carnots who organise victory for truth1 and they are1 at least1 as important as the generals who visibly fight her battles in the field4 ,priestley's reputation as a man of science rests upon his numerous and important contributions to the chemistry of gaseous bodies2 and to form a just estimate of the value of his work--of the extent to which it advanced the knowledge of fact and the development of sound theoretical views--we must reflect what chemistry was in the first half of the eighteenth century4 ,the vast science which now passes under that name had no existence4 ,air1 water1 and fire were still counted among the elemental bodies2 and though ,van ,helmont1 a century before1 had distinguished different kinds of air as gas ventosum and gas sylvestre1 and ,boyle and ,hales had experimentally defined the physical properties of air1 and discriminated some of the various kinds of ariform bodies1 no one suspected the existence of the numerous totally distinct gaseous elements which are now known1 or dreamed that the air we breathe and the water we drink are compounds of gaseous elements4 ,but1 in #aged1 a young ,scotch physician1 ,dr4 ,black1 made the first clearing in this tangled backwood of knowledge4 ,and it gives one a wonderful impression of the juvenility of scientific chemistry to think that ,lord ,brougham1 whom so many of us recollect1 attended ,black's lectures when he was a student in ,edinburgh4 ,black's researches gave the world the novel and startling conception of a gas that was a permanently elastic fluid like air1 but that differed from common air in being much heavier1 very poisonous1 and in having the properties of an acid1 capable of neutralising the strongest alkalies2 and it took the world some time to become accustomed to the notion4 ,a dozen years later1 one of the most sagacious and accurate investigators who has adorned this1 or any other1 country1 ,henry ,cavendish1 published a memoir in the 8,philosophical ,transactions10 in which he deals not only with the 8fixed air0 7now called carbonic acid or carbonic anhydride7 of ,black1 but with 8inflammable air10 or what we now term hydrogen4 ,by the rigorous application of weight and measure to all his processes1 ,cavendish implied the belief subsequently formulated by ,lavoisier1 that1 in chemical processes1 matter is neither created nor destroyed1 and indicated the path along which all future explorers must travel4 ,nor did he himself halt until this path led him1 in #aghd1 to the brilliant and fundamental discovery that water is composed of two gases united in fixed and constant proportions4 ,it is a trying ordeal for any man to be compared with ,black and ,cavendish1 and ,priestley cannot be said to stand on their level4 ,nevertheless1 his achievements are not only great in themselves1 but truly wonderful1 if we consider the disadvantages under which he laboured4 ,without the careful scientific training of ,black1 without the leisure and appliances secured by the wealth of ,cavendish1 he scaled the walls of science as so many ,englishmen have done before and since his day2 and trusting to mother wit to supply the place of training1 and to ingenuity to create apparatus out of washing tubs1 he discovered more new gases than all his predecessors put together had done4 ,he laid the foundations of gas analysis2 he discovered the complementary actions of animal and vegetable life upon the constituents of the atmosphere2 and1 finally1 he crowned his work1 this day one hundred years ago1 by the discovery of that 8pure dephlogisticated air0 to which the ,french chemists subsequently gave the name of oxygen4 ,its importance1 as the constituent of the atmosphere which disappears in the processes of respiration and combustion1 and is restored by green plants growing in sunshine1 was proved somewhat later4 ,for these brilliant discoveries1 the ,royal ,society elected ,priestley a fellow and gave him their medal1 while the ,academies of ,paris and ,st4 ,petersburg conferred their membership upon him4 ,edinburgh had made him an honorary doctor of laws at an early period of his career2 but1 ,i need hardly add1 that a man of ,priestley's opinions received no recognition from the universities of his own country4 ,that ,priestley's contributions to the knowledge of chemical fact were of the greatest importance1 and that they richly deserve all the praise that has been awarded to them1 is unquestionable2 but it must1 at the same time1 be admitted that he had no comprehension of the deeper significance of his work2 and1 so far from contributing anything to the theory of the facts which he discovered1 or assisting in their rational explanation1 his influence to the end of his life was warmly exerted in favour of error4 ,from first to last1 he was a stiff adherent of the phlogiston doctrine which was prevalent when his studies commenced2 and1 by a curious irony of fate1 the man who by the discovery of what he called 8dephlogisticated air0 furnished the essential datum for the true theory of combustion1 of respiration1 and of the composition of water1 to the end of his days fought against the inevitable corollaries from his own labours4 ,his last scientific work1 published in #ahjj1 bears the title1 8,the ,doctrine of ,phlogiston established1 and that of the ,composition of ,water refuted40 ,when ,priestley commenced his studies1 the current belief was1 that atmospheric air1 freed from accidental impurities1 is a simple elementary substance1 indestructible and unalterable1 as water was supposed to be4 ,when a combustible burned1 or when an animal breathed in air1 it was supposed that a substance1 8phlogiston10 the matter of heat and light1 passed from the burning or breathing body into it1 and destroyed its powers of supporting life and combustion4 ,thus1 air contained in a vessel in which a lighted candle had gone out1 or a living animal had breathed until it could breathe no longer1 was called 8phlogisticated40 ,the same result was supposed to be brought about by the addition of what ,priestley called 8nitrous gas0 to common air4 ,in the course of his researches1 ,priestley found that the quantity of common air which can thus become 8phlogisticated10 amounts to about one-fifth the volume of the whole quantity submitted to experiment4 ,hence it appeared that common air consists1 to the extent of four-fifths of its volume1 of air which is already 8phlogisticated20 while the other fifth is free from phlogiston1 or 8dephlogisticated40 ,on the other hand1 ,priestley found that air 8phlogisticated0 by combustion or respiration could be 8dephlogisticated10 or have the properties of pure common air restored to it1 by the action of green plants in sunshine4 ,the question1 therefore1 would naturally arise--as common air can be wholly phlogisticated by combustion1 and converted into a substance which will no longer support combustion1 is it possible to get air that shall be less phlogisticated than common air1 and consequently support combustion better than common air does8 ,now1 ,priestley says that1 in #aggd1 the possibility of obtaining air less phlogisticated than common air had not occurred to him4#ae ,but in pursuing his experiments on the evolution of air from various bodies by means of heat1 it happened that1 on the #ast of ,august #aggd1 he threw the heat of the sun1 by means of a large burning glass which he had recently obtained1 upon a substance which was then called mercurius calcinatus per se1 and which is commonly known as red precipitate4 8,i presently found that1 by means of this lens1 air was expelled from it very readily4 ,having got about three or four times as much as the bulk of my materials1 ,i admitted water to it1 and found that it was not imbibed by it4 ,but what surprised me more than ,i can well express1 was that a candle burned in this air with a remarkably vigorous flame1 very much like that enlarged flame with which a candle burns in nitrous air1 exposed to iron or lime of sulphur2 but as ,i had got nothing like this remarkable appearance from any kind of air besides this particular modification of nitrous air1 and ,i knew no nitrous acid was used in the preparation of mercurius calcinatus1 ,i was utterly at a loss how to account for it4 8,in this case also1 though ,i did not give sufficient attention to the circumstance at that time1 the flame of the candle1 besides being larger1 burned with more splendour and heat than in that species of nitrous air2 and a piece of red-hot wood sparkled in it1 exactly like paper dipped in a solution of nitre1 and it consumed very fast--an experiment which ,i had never thought of trying with nitrous air40#af ,priestley obtained the same sort of air from red lead1 but1 as he says himself1 he remained in ignorance of the properties of this new kind of air for seven months1 or until ,march #agge1 when he found that the new air behaved with 8nitrous gas0 in the same way as the dephlogisticated part of common air does2#ag but that1 instead of being diminished to four-fifths1 it almost completely vanished1 and1 therefore1 showed itself to be 8between five and six times as good as the best common air ,i have ever met with40#ah ,as this new air thus appeared to be completely free from phlogiston1 ,priestley called it 8dephlogisticated air40 ,what was the nature of this air8 ,priestley found that the same kind of air was to be obtained by moistening with the spirit of nitre 7which he terms nitrous acid7 any kind of earth that is free from phlogiston1 and applying heat2 and consequently he says3 8,there remained no doubt on my mind but that the atmospherical air1 or the thing that we breathe1 consists of the nitrous acid and earth1 with so much phlogiston as is necessary to its elasticity1 and likewise so much more as is required to bring it from its state of perfect purity to the mean condition in which we find it40#ai ,priestley's view1 in fact1 is that atmospheric air is a kind of saltpetre1 in which the potash is replaced by some unknown earth4 ,and in speculating on the manner in which saltpetre is formed1 he enunciates the hypothesis1 8that nitre is formed by a real decomposition of the air itself1 the bases that are presented to it having1 in such circumstances1 a nearer affinity with the spirit of nitre than that kind of earth with which it is united in the atmosphere40#bj ,it would have been hard for the most ingenious person to have wandered farther from the truth than ,priestley does in this hypothesis2 and1 though ,lavoisier undoubtedly treated ,priestley very ill1 and pretended to have discovered dephlogisticated air1 or oxygen1 as he called it1 independently1 we can almost forgive him1 when we reflect how different were the ideas which the great ,french chemist attached to the body which ,priestley discovered4 ,they are like two navigators of whom the first sees a new country1 but takes clouds for mountains and mirage for lowlands2 while the second determines its length and breadth1 and lays down on a chart its exact place1 so that1 thenceforth1 it serves as a guide to his successors1 and becomes a secure outpost whence new explorations may be pushed4 ,nevertheless1 as ,priestley himself somewhere remarks1 the first object of physical science is to ascertain facts1 and the service which he rendered to chemistry by the definite establishment of a large number of new and fundamentally important facts1 is such as to entitle him to a very high place among the fathers of chemical science4 ,it is difficult to say whether ,priestley's philosophical1 political1 or theological views were most responsible for the bitter hatred which was borne to him by a large body of his countrymen1#ba and which found its expression in the malignant insinuations in which ,burke1 to his everlasting shame1 indulged in the ,house of ,commons4 ,without containing much that will be new to the readers of ,hobbes1 ,spinoza1 ,collins1 ,hume1 and ,hartley1 and1 indeed1 while making no pretensions to originality1 ,priestley's 8,disquisitions relating to ,matter and ,spirit10 and his 8,doctrine of ,philosophical ,necessity illustrated10 are among the most powerful1 clear1 and unflinching expositions of materialism and necessarianism which exist in the ,english language1 and are still well worth reading4 ,priestley denied the freedom of the will in the sense of its self-determination2 he denied the existence of a soul distinct from the body2 and as a natural consequence1 he denied the natural immortality of man4 ,in relation to these matters ,english opinion1 a century ago1 was very much what it is now4 ,a man may be a necessarian without incurring graver reproach than that implied in being called a gloomy fanatic1 necessarianism1 though very shocking1 having a note of ,calvinistic orthodoxy2 but1 if a man is a materialist2 or1 if good authorities say he is and must be so1 in spite of his assertion to the contrary2 or1 if he acknowledge himself unable to see good reasons for believing in the natural immortality of man1 respectable folks look upon him as an unsafe neighbour of a cash-box1 as an actual or potential sensualist1 the more virtuous in outward seeming1 the more certainly loaded with secret 8grave personal sins40 ,nevertheless1 it is as certain as anything can be1 that ,joseph ,priestley was no gloomy fanatic1 but as cheerful and kindly a soul as ever breathed1 the idol of children2 a man who was hated only by those who did not know him1 and who charmed away the bitterest prejudices in personal intercourse2 a man who never lost a friend1 and the best testimony to whose worth is the generous and tender warmth with which his many friends vied with one another in rendering him substantial help1 in all the crises of his career4 ,the unspotted purity of ,priestley's life1 the strictness of his performance of every duty1 his transparent sincerity1 the unostentatious and deep-seated piety which breathes through all his correspondence1 are in themselves a sufficient refutation of the hypothesis1 invented by bigots to cover uncharitableness1 that such opinions as his must arise from moral defects4 ,and his statue will do as good service as the brazen image that was set upon a pole before the ,israelites1 if those who have been bitten by the fiery serpents of sectarian hatred1 which still haunt this wilderness of a world1 are made whole by looking upon the image of a heretic1 who was yet a saint4 ,though ,priestley did not believe in the natural immortality of man1 he held with an almost nave realism1 that man would be raised from the dead by a direct exertion of the power of ,god1 and thenceforward be immortal4 ,and it may be as well for those who may be shocked by this doctrine to know that views1 substantially identical with ,priestley's1 have been advocated1 since his time1 by two prelates of the ,anglican ,church3 by ,dr4 ,whately1 ,archbishop of ,dublin1 in his well-known 8,essays20#bb and by ,dr4 ,courtenay1 ,bishop of ,kingston in ,jamaica1 the first edition of whose remarkable book 8,on the ,future ,states10 dedicated to ,archbishop ,whately1 was published in #ahdc and the second in #aheg4 ,according to ,bishop ,courtenay1 8,the death of the body will cause a cessation of all the activity of the mind by way of natural consequence2 to continue for ever ,,unless the ,creator should interfere40 ,and again3-- 8,the natural end of human existence is the #8first death1' the dreamless slumber of the grave1 wherein man lies spellbound1 soul and body1 under the dominion of sin and death--that whatever modes of conscious existence1 whatever future states of #8life' or of #8torment' beyond ,hades are reserved for man1 are results of our blessed ,lord's victory over sin and death2 that the resurrection of the dead must be preliminary to their entrance into either of the future states1 and that the nature and even existence of these states and even the mere fact that there is a futurity of consciousness1 can be known only through ,god's revelation of ,himself in the ,person and the ,gospel of ,his ,son40--,p4 #chi4 ,and now hear ,priestley3-- 8,man1 according to this system 7of materialism71 is no more than we now see of him4 ,his being commences at the time of his conception1 or perhaps at an earlier period4 ,the corporeal and mental faculties1 in being in the same substance1 grow1 ripen1 and decay together2 and whenever the system is dissolved it continues in a state of dissolution till it shall please that ,almighty ,being who called it into existence to restore it to life again40--8,matter and ,spirit10 p4 #di4 ,and again3-- 8,the doctrine of the ,scripture is1 that ,god made man of the dust of the ground1 and by simply animating this organised matter1 made man that living percipient and intelligent being that he is4 ,according to ,revelation1 death is a state of rest and insensibility1 and our only though sure hope of a future life is founded on the doctrine of the resurrection of the whole man at some distant period2 this assurance being sufficiently confirmed to us both by the evident tokens of a ,divine commission attending the persons who delivered the doctrine1 and especially by the actual resurrection of ,jesus ,christ1 which is more authentically attested than any other fact in history40--,ibid41 p4 #bdg4 ,we all know that 8a saint in crape is twice a saint in lawn20 but it is not yet admitted that the views which are consistent with such saintliness in lawn1 become diabolical when held by a mere dissenter4#bc ,i am not here either to defend or to attack ,priestley's philosophical views1 and ,i cannot say that ,i am personally disposed to attach much value to episcopal authority in philosophical questions2 but it seems right to call attention to the fact1 that those of ,priestley's opinions which have brought most odium upon him1 have been openly promulgated1 without challenge1 by persons occupying the highest positions in the ,state ,church4 ,i must confess that what interests me most about ,priestley's materialism1 is the evidence that he saw dimly the seed of destruction which such materialism carries within its own bosom4 ,in the course of his reading for his 8,history of ,discoveries relating to ,vision1 ,light1 and ,colours10 he had come upon the speculations of ,boscovich and ,michell1 and had been led to admit the sufficiently obvious truth that our knowledge of matter is a knowledge of its properties2 and that of its substance--if it have a substance--we know nothing4 ,and this led to the further admission that1 so far as we can know1 there may be no difference between the substance of matter and the substance of spirit 78,disquisitions10 p4 #af74 ,a step farther would have shown ,priestley that his materialism was1 essentially1 very little different from the ,idealism of his contemporary1 the ,bishop of ,cloyne4 ,as ,priestley's philosophy is mainly a clear statement of the views of the deeper thinkers of his day1 so are his political conceptions based upon those of ,locke4 ,locke's aphorism that 8the end of government is the good of mankind10 is thus expanded by ,priestley3-- 8,it must necessarily be understood1 therefore1 whether it be expressed or not1 that all people live in society for their mutual advantage2 so that the good and happiness of the members1 that is1 of the majority of the members1 of any state1 is the great standard by which everything relating to that state must finally be determined40#bd ,the little sentence here interpolated1 8that is1 of the majority of the members of any state10 appears to be that passage which suggested to ,bentham1 according to his own acknowledgment1 the famous 8greatest happiness0 formula1 which by substituting 8happiness0 for 8good10 has converted a noble into an ignoble principle4 ,but ,i do not call to mind that there is any utterance in ,locke quite so outspoken as the following passage in the 8,essay on the ,first ,principles of ,government40 ,after laying down as 8a fundamental maxim in all governments10 the proposition that 8kings1 senators1 and nobles0 are 8the servants of the public10 ,priestley goes on to say3-- 8,but in the largest states1 if the abuses of the government should at any time be great and manifest2 if the servants of the people1 forgetting their masters and their masters' interest1 should pursue a separate one of their own2 if1 instead of considering that they are made for the people1 they should consider the people as made for them2 if the oppressions and violation of right should be great1 flagrant1 and universally resented2 if the tyrannical governors should have no friends but a few sycophants1 who had long preyed upon the vitals of their fellow-citizens1 and who might be expected to desert a government whenever their interests should be detached from it2 if1 in consequence of these circumstances1 it should become manifest that the risk which would be run in attempting a revolution would be trifling1 and the evils which might be apprehended from it were far less than those which were actually suffered and which were daily increasing2 in the name of ,god1 ,i ask1 what principles are those which ought to restrain an injured and insulted people from asserting their natural rights1 and from changing or even punishing their governors--that is1 their servants--who had abused their trust1 or from altering the whole form of their government1 if it appeared to be of a structure so liable to abuse80 ,as a ,dissenter1 subject to the operation of the ,corporation and ,test ,acts1 and as a ,unitarian1 excluded from the benefit of the ,toleration ,act1 it is not surprising to find that ,priestley had very definite opinions about ,ecclesiastical ,establishments2 the only wonder is that these opinions were so moderate as the following passages show them to have been3-- 8,ecclesiastical authority may have been necessary in the infant state of society1 and1 for the same reason1 it may perhaps continue to be1 in some degree1 necessary as long as society is imperfect2 and therefore may not be entirely abolished till civil governments have arrived at a much greater degree of perfection4 ,if1 therefore1 ,i were asked whether ,i should approve of the immediate dissolution of all the ecclesiastical establishments in ,europe1 ,i should answer1 ,no4444 ,let experiment be first made of alterations1 or1 which is the same thing1 of better establishments than the present4 ,let them be reformed in many essential articles1 and then not thrown aside entirely till it be found by experience that no good can be made of them40 ,priestley goes on to suggest four such reforms of a capital nature3-- 8#a4 ,let the ,articles of ,faith to be subscribed by candidates for the ministry be greatly reduced4 ,in the formulary of the ,church of ,england1 might not thirty-eight out of the thirty-nine be very well spared8 ,it is a reproach to any ,christian establishment if every man cannot claim the benefit of it who can say that he believes in the religion of ,jesus ,christ as it is set forth in the ,new ,testament4 ,you say the terms are so general that even ,deists would quibble and insinuate themselves4 ,i answer that all the articles which are subscribed at present1 by no means exclude ,deists who will prevaricate2 and upon this scheme you would at least exclude fewer honest men40#be ,the second reform suggested is the equalisation1 in proportion to work done1 of the stipends of the clergy2 the third1 the exclusion of the bishops from ,parliament2 and the fourth1 complete toleration1 so that every man may enjoy the rights of a citizen1 and be qualified to serve his country1 whether he belong to the ,established ,church or not4 ,opinions such as those ,i have quoted1 respecting the duties and the responsibilities of governors1 are the commonplaces of modern ,liberalism2 and ,priestley's views on ,ecclesiastical ,establishments would1 ,i fear1 meet with but a cool reception1 as altogether too conservative1 from a large proportion of the lineal descendants of the people who taught their children to cry 8,damn ,priestley20 and1 with that love for the practical application of science which is the source of the greatness of ,birmingham1 tried to set fire to the doctor's house with sparks from his own electrical machine2 thereby giving the man they called an incendiary and raiser of sedition against ,church and ,king1 an appropriately experimental illustration of the nature of arson and riot4 ,if ,i have succeeded in putting before you the main features of ,priestley's work1 its value will become apparent1 when we compare the condition of the ,english nation1 as he knew it1 with its present state4 ,the fact that ,france has been for eighty-five years trying1 without much success1 to right herself after the great storm of the ,revolution1 is not unfrequently cited among us1 as an indication of some inherent incapacity for self-government among the ,french people4 ,i think1 however1 that ,englishmen who argue thus1 forget that1 from the meeting of the ,long ,parliament in #afdj1 to the last ,stuart rebellion in #agde1 is a hundred and five years1 and that1 in the middle of the last century1 we had but just safely freed ourselves from our ,bourbons and all that they represented4 ,the corruption of our state was as bad as that of the ,second ,empire4 ,bribery was the instrument of government1 and peculation its reward4 ,four-fifths of the seats in the ,house of ,commons were more or less openly dealt with as property4 ,a minister had to consider the state of the vote market1 and the sovereign secured a sufficiency of 8king's friends0 by payments allotted with retail1 rather than royal1 sagacity4 ,barefaced and brutal immorality and intemperance pervaded the land1 from the highest to the lowest classes of society4 ,the ,established ,church was torpid1 so far as it was not a scandal2 but those who dissented from it came within the meshes of the ,act of ,uniformity1 the ,test ,act1 and the ,corporation ,act4 ,by law1 such a man as ,priestley1 being a ,unitarian1 could neither teach nor preach1 and was liable to ruinous fines and long imprisonment4#bf ,in those days1 the guns that were pointed by the ,church against the ,dissenters were shotted4 ,the law was a cesspool of iniquity and cruelty4 ,adam ,smith was a new prophet whom few regarded1 and commerce was hampered by idiotic impediments1 and ruined by still more absurd help1 on the part of government4 ,birmingham1 though already the centre of a considerable industry1 was a mere village as compared with its present extent4 ,people who travelled went about armed1 by reason of the abundance of highwaymen and the paucity and inefficiency of the police4 ,stage coaches had not reached ,birmingham1 and it took three days to get to ,london4 ,even canals were a recent and much opposed invention4 ,newton had laid the foundation of a mechanical conception of the physical universe3 ,hartley1 putting a modern face upon ancient materialism1 had extended that mechanical conception to psychology2 ,linnus and ,haller were beginning to introduce method and order into the chaotic accumulation of biological facts4 ,but those parts of physical science which deal with heat1 electricity1 and magnetism1 and above all1 chemistry1 in the modern sense1 can hardly be said to have had an existence4 ,no one knew that two of the old elemental bodies1 air and water1 are compounds1 and that a third1 fire1 is not a substance but a motion4 ,the great industries that have grown out of the applications of modern scientific discoveries had no existence1 and the man who should have foretold their coming into being in the days of his son1 would have been regarded as a mad enthusiast4 ,in common with many other excellent persons1 ,priestley believed that man is capable of reaching1 and will eventually attain1 perfection4 ,if the temperature of space presented no obstacle1 ,i should be glad to entertain the same idea2 but judging from the past progress of our species1 ,i am afraid that the globe will have cooled down so far1 before the advent of this natural millennium1 that we shall be1 at best1 perfected ,esquimaux4 ,for all practical purposes1 however1 it is enough that man may visibly improve his condition in the course of a century or so4 ,and1 if the picture of the state of things in ,priestley's time1 which ,i have just drawn1 have any pretence to accuracy1 ,i think it must be admitted that there has been a considerable change for the better4 ,i need not advert to the well-worn topic of material advancement1 in a place in which the very stones testify to that progress--in the town of ,watt and of ,boulton4 ,i will only remark1 in passing1 that material advancement has its share in moral and intellectual progress4 ,becky ,sharp's acute remark that it is not difficult to be virtuous on ten thousand a year1 has its application to nations2 and it is futile to expect a hungry and squalid population to be anything but violent and gross4 ,but as regards other than material welfare1 although perfection is not yet in sight--even from the mast-head--it is surely true that things are much better than they were4 ,take the upper and middle classes as a whole1 and it may be said that open immorality and gross intemperance have vanished4 ,four and six bottle men are as extinct as the dodo4 ,women of good repute do not gamble1 and talk modelled upon ,dean ,swift's 8,art of ,polite ,conversation0 would be tolerated in no decent kitchen4 ,members of the legislature are not to be bought2 and constituents are awakening to the fact that votes must not be sold--even for such trifles as rabbits and tea and cake4 ,political power has passed into the hands of the masses of the people4 ,those whom ,priestley calls their servants have recognised their position1 and have requested the master to be so good as to go to school and fit himself for the administration of his property4 ,no civil disability attaches to any one on theological grounds1 and the highest offices of the state are open to ,papist1 ,jew1 or ,secularist4#bg ,whatever men's opinions as to the policy of ,establishment1 no one can hesitate to admit that the clergy of the ,church are men of pure life and conversation1 zealous in the discharge of their duties2 and1 at present1 apparently1 more bent on prosecuting one another than on meddling with ,dissenters4 ,theology itself has broadened so much1 that ,anglican divines put forward doctrines more liberal than those of ,priestley2 and1 in our state-supported churches1 one listener may hear a sermon to which ,bossuet might have given his approbation1 while another may hear a discourse in which ,socrates would find nothing new4 ,but great as these changes may be1 they sink into insignificance beside the progress of physical science1 whether we consider the improvement of methods of investigation1 or the increase in bulk of solid knowledge4 ,consider that the labours of ,laplace1 of ,young1 of ,davy1 and of ,faraday2 of ,cuvier1 of ,lamarck1 and of ,robert ,brown2 of ,von ,baer1 and of ,schwann2 of ,smith and of ,hutton1 have all been carried on since ,priestley discovered oxygen2 and consider that they are now things of the past1 concealed by the industry of those who have built upon them1 as the first founders of a coral reef are hidden beneath the life's work of their successors2 consider that the methods of physical science are slowly spreading into all investigations1 and that proofs as valid as those required by her canons of investigation1 are being demanded of all doctrines which ask for men's assent2 and you will have a faint image of the astounding difference in this respect between the nineteenth century and the eighteenth4 ,if we ask what is the deeper meaning of all these vast changes1 ,i think there can be but one reply4 ,they mean that reason has asserted and exercised her primacy over all provinces of human activity3 that ecclesiastical authority has been relegated to its proper place2 that the good of the governed has been finally recognised as the end of government1 and the complete responsibility of governors to the people as its means2 and that the dependence of natural phenomena in general1 on the laws of action of what we call matter has become an axiom4 ,but it was to bring these things about1 and to enforce the recognition of these truths1 that ,joseph ,priestley laboured4 ,if the nineteenth century is other and better than the eighteenth1 it is1 in great measure1 to him and to such men as he1 that we owe the change4 ,if the twentieth century is to be better than the nineteenth1 it will be because there are among us men who walk in ,priestley's footsteps4 ,such men are not those whom their own generation delights to honour2 such men1 in fact1 rarely trouble themselves about honour1 but ask1 in another spirit than ,falstaff's1 8,what is honour8 ,who hath it8 ,he that died o' ,wednesday40 ,but whether ,priestley's lot be theirs1 and a future generation1 in justice and in gratitude1 set up their statues2 or whether their names and fame are blotted out from remembrance1 their work will live as long as time endures4 ,to all eternity1 the sum of truth and right will have been increased by their means2 to all eternity1 falsehood and injustice will be the weaker because they have lived4 ,,vi4 ,,on ,,the ,,method ,,of ,,zadig3 ,,retrospective ,,prophecy ,,as ,a ,,function ,,of ,,science4 8,une marque plus sre que toutes celles de ,zadig0--,,cuvier4#bh ,it is a usual and a commendable practice to preface the discussion of the views of a philosophic thinker by some account of the man and of the circumstances which shaped his life and coloured his way of looking at things2 but1 though ,zadig is cited in one of the most important chapters of ,cuvier's greatest work1 little is known about him1 and that little might perhaps be better authenticated than it is4 ,it is said that he lived at ,babylon in the time of ,king ,moabdar2 but the name of ,moabdar does not appear in the list of ,babylonian sovereigns brought to light by the patience and the industry of the decipherers of cuneiform inscriptions in these later years2 nor indeed am ,i aware that there is any other authority for his existence than that of the biographer of ,zadig1 one ,arouet de ,voltaire1 among whose more conspicuous merits strict historical accuracy is perhaps hardly to be reckoned4 ,happily ,zadig is in the position of a great many other philosophers4 ,what he was like when he was in the flesh1 indeed whether he existed at all1 are matters of no great consequence4 ,what we care about in a light is that it shows the way1 not whether it is lamp or candle1 tallow or wax4 ,our only real interest in ,zadig lies in the conceptions of which he is the putative father2 and his biographer has stated these with so much clearness and vivacious illustration1 that we need hardly feel a pang1 even if critical research should prove ,king ,moabdar and all the rest of the story to be unhistorical1 and reduce ,zadig himself to the shadowy condition of a solar myth4 ,voltaire tells us that1 disenchanted with life by sundry domestic misadventures1 ,zadig withdrew from the turmoil of ,babylon to a secluded retreat on the banks of the ,euphrates1 where he beguiled his solitude by the study of nature4 ,the manifold wonders of the world of life had a particular attraction for the lonely student2 incessant and patient observation of the plants and animals about him sharpened his naturally good powers of observation and of reasoning2 until1 at length1 he acquired a sagacity which enabled him to perceive endless minute differences among objects which1 to the untutored eye1 appeared absolutely alike4 ,it might have been expected that this enlargement of the powers of the mind and of its store of natural knowledge could tend to nothing but the increase of a man's own welfare and the good of his fellow-men4 ,but ,zadig was fated to experience the vanity of such expectations4 ,one day1 walking near a little wood1 he saw1 hastening that way1 one of the ,queen's chief eunuchs1 followed by a troop of officials1 who appeared to be in the greatest anxiety1 running hither and thither like men distraught1 in search of some lost treasure4 8,young man10 cried the eunuch1 8have you seen the ,queen's dog80 ,zadig answered modestly1 8,a bitch1 ,i think1 not a dog40 8,quite right10 replied the eunuch2 and ,zadig continued1 8,a very small spaniel who has lately had puppies2 she limps with the left foreleg1 and has very long ears40 8,ah6 you have seen her then10 said the breathless eunuch4 8,no10 answered ,zadig1 8,i have not seen her2 and ,i really was not aware that the ,queen possessed a spaniel40 ,by an odd coincidence1 at the very same time1 the handsomest horse in the ,king's stables broke away from his groom in the ,babylonian plains4 ,the grand huntsman and all his staff were seeking the horse with as much anxiety as the eunuch and his people the spaniel2 and the grand huntsman asked ,zadig if he had not seen the ,king's horse go that way4 8,a first-rate galloper1 small-hoofed1 five feet high2 tail three feet and a half long2 cheek pieces of the bit of twenty-three carat gold2 shoes silver80 said ,zadig4 8,which way did he go8 ,where is he80 cried the grand huntsman4 8,i have not seen anything of the horse1 and ,i never heard of him before10 replied ,zadig4 ,the grand huntsman and the chief eunuch made sure that ,zadig had stolen both the ,king's horse and the ,queen's spaniel1 so they haled him before the ,high ,court of ,desterham1 which at once condemned him to the knout1 and transportation for life to ,siberia4 ,but the sentence was hardly pronounced when the lost horse and spaniel were found4 ,so the judges were under the painful necessity of reconsidering their decision3 but they fined ,zadig four hundred ounces of gold for saying he had seen that which he had not seen4 ,the first thing was to pay the fine2 afterwards ,zadig was permitted to open his defence to the court1 which he did in the following terms3 8,stars of justice1 abysses of knowledge1 mirrors of truth1 whose gravity is as that of lead1 whose inflexibility is as that of iron1 who rival the diamond in clearness1 and possess no little affinity with gold2 since ,i am permitted to address your august assembly1 ,i swear by ,ormuzd that ,i have never seen the respectable lady dog of the queen1 nor beheld the sacrosanct horse of the ,king of ,kings4 8,this is what happened4 ,i was taking a walk towards the little wood near which ,i subsequently had the honour to meet the venerable chief eunuch and the most illustrious grand huntsman4 ,i noticed the track of an animal in the sand1 and it was easy to see that it was that of a small dog4 ,long faint streaks upon the little elevations of sand between the footmarks convinced me that it was a she dog with pendent dugs1 showing that she must have had puppies not many days since4 ,other scrapings of the sand1 which always lay close to the marks of the forepaws1 indicated that she had very long ears2 and1 as the imprint of one foot was always fainter than those of the other three1 ,i judged that the lady dog of our august ,queen was1 if ,i may venture to say so1 a little lame4 8,with respect to the horse of the ,king of ,kings1 permit me to observe that1 wandering through the paths which traverse the wood1 ,i noticed the marks of horse-shoes4 ,they were all equidistant4 #8,ah6' said ,i1 #8this is a famous galloper4' ,in a narrow alley1 only seven feet wide1 the dust upon the trunks of the trees was a little disturbed at three feet and a half from the middle of the path4 #8,this horse1' said ,i to myself1 #8had a tail three feet and a half long1 and1 lashing it from one side to the other1 he has swept away the dust4' ,branches of the trees met overhead at the height of five feet1 and under them ,i saw newly fallen leaves2 so ,i knew that the horse had brushed some of the branches1 and was therefore five feet high4 ,as to his bit1 it must have been made of twenty-three carat gold1 for he had rubbed it against a stone1 which turned out to be a touchstone1 with the properties of which ,i am familiar by experiment4 ,lastly1 by the marks which his shoes left upon pebbles of another kind1 ,i was led to think that his shoes were of fine silver40 ,all the judges admired ,zadig's profound and subtle discernment2 and the fame of it reached even the ,king and the ,queen4 ,from the ante-rooms to the presence-chamber1 ,zadig's name was in everybody's mouth2 and1 although many of the magi were of opinion that he ought to be burnt as a sorcerer1 the ,king commanded that the four hundred ounces of gold which he had been fined should be restored to him4 ,so the officers of the court went in state with the four hundred ounces2 only they retained three hundred and ninety-eight for legal expenses1 and their servants expected fees4 ,those who are interested in learning more of the fateful history of ,zadig must turn to the original2 we are dealing with him only as a philosopher1 and this brief excerpt suffices for the exemplification of the nature of his conclusions and of the method by which he arrived at them4 ,these conclusions may be said to be of the nature of retrospective prophecies2 though it is perhaps a little hazardous to employ phraseology which perilously suggests a contradiction in terms--the word 8prophecy0 being so constantly in ordinary use restricted to 8foretelling40 ,strictly1 however1 the term prophecy as much applies to outspeaking as to foretelling2 and1 even in the restricted sense of 8divination10 it is obvious that the essence of the prophetic operation does not lie in its backward or forward relation to the course of time1 but in the fact that it is the apprehension of that which lies out of the sphere of immediate knowledge2 the seeing of that which to the natural sense of the seer is invisible4 ,the foreteller asserts that1 at some future time1 a properly situated observer will witness certain events2 the clairvoyant declares that1 at this present time1 certain things are to be witnessed a thousand miles away2 the retrospective prophet 7would that there were such a word as 8backteller607 affirms that so many hours or years ago1 such and such things were to be seen4 ,in all these cases1 it is only the relation to time which alters--the process of divination beyond the limits of possible direct knowledge remains the same4 ,no doubt it was their instinctive recognition of the analogy between ,zadig's results and those obtained by authorised inspiration which inspired the ,babylonian magi with the desire to burn the philosopher4 ,zadig admitted that he had never either seen or heard of the horse of the king or of the spaniel of the queen2 and yet he ventured to assert in the most positive manner that animals answering to their description did actually exist1 and ran about the plains of ,babylon4 ,if his method was good for the divination of the course of events ten hours old1 why should it not be good for those of ten years or ten centuries past2 nay1 might it not extend to ten thousand years and justify the impious in meddling with the traditions of ,oannes and the fish1 and all the sacred foundations of ,babylonian cosmogony8 ,but this was not the worst4 ,there was another consideration which obviously dictated to the more thoughtful of the magi the propriety of burning ,zadig out of hand4 ,his defence was worse than his offence4 ,it showed that his mode of divination was fraught with danger to magianism in general4 ,swollen with the pride of human reason1 he had ignored the established canons of magian lore2 and1 trusting to what after all was mere carnal common sense1 he professed to lead men to a deeper insight into nature than magian wisdom1 with all its lofty antagonism to everything common1 had ever reached4 ,what1 in fact1 lay at the foundation of all ,zadig's arguments but the coarse commonplace assumption1 upon which every act of our daily lives is based1 that we may conclude from an effect to the pre-existence of a cause competent to produce that effect8 ,the tracks were exactly like those which dogs and horses leave2 therefore they were the effects of such animals as causes4 ,the marks at the sides of the fore prints of the dog track were exactly such as would be produced by long trailing ears2 therefore the dog's long ears were the causes of these marks--and so on4 ,nothing can be more hopelessly vulgar1 more unlike the majestic development of a system of grandly unintelligible conclusions from sublimely inconceivable premisses1 such as delights the magian heart4 ,in fact1 ,zadig's method was nothing but the method of all mankind4 ,retrospective prophecies1 far more astonishing for their minute accuracy than those of ,zadig1 are familiar to those who have watched the daily life of nomadic people4 ,from freshly broken twigs1 crushed leaves1 disturbed pebbles1 and imprints hardly discernible by the untrained eye1 such graduates in the ,university of ,nature will divine1 not only the fact that a party has passed that way1 but its strength1 its composition1 the course it took1 and the number of hours or days which have elapsed since it passed4 ,but they are able to do this because1 like ,zadig1 they perceive endless minute differences where untrained eyes discern nothing2 and because the unconscious logic of common sense compels them to account for these effects by the causes which they know to be competent to produce them4 ,and such mere methodised savagery was to discover the hidden things of nature better than priori deductions from the nature of ,ormuzd--perhaps to give a history of the past1 in which ,oannes would be altogether ignored6 ,decidedly it were better to burn this man at once4 ,if instinct1 or an unwonted use of reason1 led ,moabdar's magi to this conclusion two or three thousand years ago1 all that can be said is that subsequent history has fully justified them4 ,for the rigorous application of ,zadig's logic to the results of accurate and long-continued observation has founded all those sciences which have been termed historical or paltiological1 because they are retrospectively prophetic and strive towards the reconstruction in human imagination of events which have vanished and ceased to be4 ,history1 in the ordinary acceptation of the word1 is based upon the interpretation of documentary evidence2 and documents would have no evidential value unless historians were justified in their assumption that they have come into existence by the operation of causes similar to those of which documents are1 in our present experience1 the effects4 ,if a written history can be produced otherwise than by human agency1 or if the man who wrote a given document was actuated by other than ordinary human motives1 such documents are of no more evidential value than so many arabesques4 ,archology1 which takes up the thread of history beyond the point at which documentary evidence fails us1 could have no existence1 except for our well-grounded confidence that monuments and works of art or artifice1 have never been produced by causes different in kind from those to which they now owe their origin4 ,and geology1 which traces back the course of history beyond the limits of archology1 could tell us nothing except for the assumption that1 millions of years ago1 water1 heat1 gravitation1 friction1 animal and vegetable life1 caused effects of the same kind as they do now4 ,nay1 even physical astronomy1 in so far as it takes us back to the uttermost point of time which paltiological science can reach1 is founded upon the same assumption4 ,if the law of gravitation ever failed to be true1 even to the smallest extent1 for that period1 the calculations of the astronomer have no application4 ,the power of prediction1 of prospective prophecy1 is that which is commonly regarded as the great prerogative of physical science4 ,and truly it is a wonderful fact that one can go into a shop and buy for small price a book1 the 8,nautical ,almanac10 which will foretell the exact position to be occupied by one of ,jupiter's moons six months hence2 nay more1 that1 if it were worth while1 the ,astronomer ,royal could furnish us with as infallible a prediction applicable to #aihj or #bihj4 ,but astronomy is not less remarkable for its power of retrospective prophecy4 ,thales1 oldest of ,greek philosophers1 the dates of whose birth and death are uncertain1 but who flourished about #fjj ,b4,c41 is said to have foretold an eclipse of the sun which took place in his time during a battle between the ,medes and the ,lydians4 ,sir ,george ,airy has written a very learned and interesting memoir#bi in which he proves that such an eclipse was visible in ,lydia on the afternoon of the #bhth of ,may in the year #ehe ,b4,c4 ,no one doubts that1 on the day and at the hour mentioned by the ,astronomer ,royal1 the people of ,asia ,minor saw the face of the sun totally obscured4 ,but1 though we implicitly believe this retrospective prophecy1 it is incapable of verification4 ,in the total absence of historical records1 it is impossible even to conceive any means of ascertaining directly whether the eclipse of ,thales happened or not4 ,all that can be said is1 that the prospective prophecies of the astronomer are always verified2 and that1 inasmuch as his retrospective prophecies are the result of following backwards1 the very same method as that which invariably leads to verified results1 when it is worked forwards1 there is as much reason for placing full confidence in the one as in the other4 ,retrospective prophecy is therefore a legitimate function of astronomical science2 and if it is legitimate for one science it is legitimate for all2 the fundamental axiom on which it rests1 the constancy of the order of nature1 being the common foundation of all scientific thought4 ,indeed1 if there can be grades in legitimacy1 certain branches of science have the advantage over astronomy1 in so far as their retrospective prophecies are not only susceptible of verification1 but are sometimes strikingly verified4 ,such a science exists in that application of the principles of biology to the interpretation of the animal and vegetable remains imbedded in the rocks which compose the surface of the globe1 which is called ,palontology4 ,at no very distant time1 the question whether these so-called 8fossils0 were really the remains of animals and plants was hotly disputed4 ,very learned persons maintained that they were nothing of the kind1 but a sort of concretion1 or crystallisation1 which had taken place within the stone in which they are found2 and which simulated the forms of animal and vegetable life1 just as frost on a window-pane imitates vegetation4 ,at the present day1 it would probably be impossible to find any sane advocate of this opinion2 and the fact is rather surprising1 that among the people from whom the circle-squarers1 perpetual-motioners1 flat-earth men and the like1 are recruited1 to say nothing of table-turners and spirit-rappers1 somebody has not perceived the easy avenue to nonsensical notoriety open to any one who will take up the good old doctrine1 that fossils are all lusus natur4 ,the position would be impregnable1 inasmuch as it is quite impossible to prove the contrary4 ,if a man choose to maintain that a fossil oyster shell1 in spite of its correspondence1 down to every minutest particular1 with that of an oyster fresh taken out of the sea1 was never tenanted by a living oyster1 but is a mineral concretion1 there is no demonstrating his error4 ,all that can be done is to show him that1 by a parity of reasoning1 he is bound to admit that a heap of oyster shells outside a fishmonger's door may also be 8sports of nature10 and that a mutton bone in a dust-bin may have had the like origin4 ,and when you cannot prove that people are wrong1 but only that they are absurd1 the best course is to let them alone4 ,the whole fabric of palontology1 in fact1 falls to the ground unless we admit the validity of ,zadig's great principle1 that like effects imply like causes2 and that the process of reasoning from a shell1 or a tooth1 or a bone1 to the nature of the animal to which it belonged1 rests absolutely on the assumption that the likeness of this shell1 or tooth1 or bone1 to that of some animal with which we are already acquainted1 is such that we are justified in inferring a corresponding degree of likeness in the rest of the two organisms4 ,it is on this very simple principle1 and not upon imaginary laws of physiological correlation1 about which1 in most cases1 we know nothing whatever1 that the so-called restorations of the palontologist are based4 ,abundant illustrations of this truth will occur to every one who is familiar with palontology2 none is more suitable than the case of the so-called ,belemnites4 ,in the early days of the study of fossils1 this name was given to certain elongated stony bodies1 ending at one extremity in a conical point1 and truncated at the other1 which were commonly reputed to be thunderbolts1 and as such to have descended from the sky4 ,they are common enough in some parts of ,england2 and1 in the condition in which they are ordinarily found1 it might be difficult to give satisfactory reasons for denying them to be merely mineral bodies4 ,they appear1 in fact1 to consist of nothing but concentric layers of carbonate of lime1 disposed in subcrystalline fibres1 or prisms1 perpendicular to the layers4 ,among a great number of specimens of these ,belemnites1 however1 it was soon observed that some showed a conical cavity at the blunt end2 and1 in still better preserved specimens1 this cavity appeared to be divided into chambers by delicate saucer-shaped partitions1 situated at regular intervals one above the other4 ,now there is no mineral body which presents any structure comparable to this1 and the conclusion suggested itself that the ,belemnites must be the effects of causes other than those which are at work in inorganic nature4 ,on close examination1 the saucer-shaped partitions were proved to be all perforated at one point1 and the perforations being situated exactly in the same line1 the chambers were seen to be traversed by a canal1 or siphuncle1 which thus connected the smallest or apical chamber with the largest4 ,there is nothing like this in the vegetable world2 but an exactly corresponding structure is met with in the shells of two kinds of existing animals1 the pearly ,nautilus and the ,spirula1 and only in them4 ,these animals belong to the same division--the ,cephalopoda--as the cuttle-fish1 the squid1 and the octopus4 ,but they are the only existing members of the group which possess chambered1 siphunculated shells2 and it is utterly impossible to trace any physiological connection between the very peculiar structural characters of a cephalopod and the presence of a chambered shell4 ,in fact1 the squid has1 instead of any such shell1 a horny 8pen10 the cuttle-fish has the so-called 8cuttle-bone10 and the octopus has no shell1 or1 at most1 a mere rudiment of one4 ,nevertheless1 seeing that there is nothing in nature at all like the chambered shell of the ,belemnite1 except the shells of the ,nautilus and of the ,spirula1 it was legitimate to prophesy that the animal from which the fossil proceeded must have belonged to the group of the ,cephalopoda4 ,nautilus and ,spirula are both very rare animals1 but the progress of investigation brought to light the singular fact1 that1 though each has the characteristic cephalopodous organisation1 it is very different from the other4 ,the shell of ,nautilus is external1 that of ,spirula internal2 ,nautilus has four gills1 ,spirula two2 ,nautilus has multitudinous tentacles1 ,spirula has only ten arms beset with horny rimmed suckers2 ,spirula1 like the squids and cuttle-fishes1 which it closely resembles1 has a bag of ink which it squirts out to cover its retreat when alarmed2 ,nautilus has none4 ,no amount of physiological reasoning could enable any one to say whether the animal which fabricated the ,belemnite was more like ,nautilus1 or more like ,spirula4 ,but the accidental discovery of ,belemnites in due connection with black elongated masses which were certainly fossilised ink-bags1 inasmuch as the ink could be ground up and used for painting as well as if it were recent sepia1 settled the question2 and it became perfectly safe to prophesy that the creature which fabricated the ,belemnite was a two-gilled cephalopod with suckers on its arms1 and with all the other essential features of our living squids1 cuttle-fishes1 and ,spirul4 ,the palontologist was1 by this time1 able to speak as confidently about the animal of the ,belemnite1 as ,zadig was respecting the queen's spaniel4 ,he could give a very fair description of its external appearance1 and even enter pretty fully into the details of its internal organisation1 and yet could declare that neither he1 nor any one else1 had ever seen one4 ,and as the queen's spaniel was found1 so happily has the animal of the ,belemnite2 a few exceptionally preserved specimens having been discovered1 which completely verify the retrospective prophecy of those who interpreted the facts of the case by due application of the method of ,zadig4 ,these ,belemnites flourished in prodigious abundance in the seas of the mesozoic or secondary age of the world's geological history2 but no trace of them has been found in any of the tertiary deposits1 and they appear to have died out towards the close of the mesozoic epoch4 ,the method of ,zadig1 therefore1 applies in full force to the events of a period which is immeasurably remote1 which long preceded the origin of the most conspicuous mountain masses of the present world1 and the deposition1 at the bottom of the ocean1 of the rocks which form the greater part of the soil of our present continents4 ,the ,euphrates itself1 at the mouth of which ,oannes landed1 is a thing of yesterday compared with a ,belemnite2 and even the liberal chronology of ,magian cosmogony fixes the beginning of the world only at a time when other applications of ,zadig's method afford convincing evidence that1 could we have been there to see1 things would have looked very much as they do now4 ,truly the magi were wise in their generation2 they foresaw rightly that this pestilent application of the principles of common sense1 inaugurated by ,zadig1 would be their ruin4 ,but it may be said that the method of ,zadig1 which is simple reasoning from analogy1 does not account for the most striking feats of modern palontology--the reconstruction of entire animals from a tooth or perhaps a fragment of a bone2 and it may be justly urged that ,cuvier1 the great master of this kind of investigation1 gave a very different account of the process which yielded such remarkable results4 ,cuvier is not the first man of ability who has failed to make his own mental processes clear to himself1 and he will not be the last4 ,the matter can be easily tested4 ,search the eight volumes of the 8,recherches sur les ,ossemens fossiles0 from cover to cover1 and nothing but the application of the method of ,zadig will be found in the arguments by which a fragment of a skeleton is made to reveal the characters of the animal to which it belonged4 ,there is one well-known case which may represent all4 ,it is an excellent illustration of ,cuvier's sagacity1 and he evidently takes some pride in telling his story about it4 ,a split slab of stone arrived from the quarries of ,montmartre1 the two halves of which contained the greater part of the skeleton of a small animal4 ,on careful examinations of the characters of the teeth and of the lower jaw1 which happened to be exposed1 ,cuvier assured himself that they presented such a very close resemblance to the corresponding parts in the living opossums that he at once assigned the fossil to that genus4 ,now the opossums are unlike most mammals in that they possess two bones attached to the fore part of the pelvis1 which are commonly called 8marsupial bones40 ,the name is a misnomer1 originally conferred because it was thought that these bones have something to do with the support of the pouch1 or marsupium1 with which some1 but not all1 of the opossums are provided4 ,as a matter of fact1 they have nothing to do with the support of the pouch1 and they exist as much in those opossums which have no pouches as in those which possess them4 ,in truth1 no one knows what the use of these bones may be1 nor has any valid theory of their physiological import yet been suggested4 ,and if we have no knowledge of the physiological importance of the bones themselves1 it is obviously absurd to pretend that we are able to give physiological reasons why the presence of these bones is associated with certain peculiarities of the teeth and of the jaws4 ,if any one knows why four molar teeth and an inflected angle of the jaw are very generally found along with marsupial bones1 he has not yet communicated that knowledge to the world4 ,if1 however1 ,zadig was right in concluding from the likeness of the hoof-prints which he observed to a horse's that the creature which made them had a tail like that of a horse1 ,cuvier1 seeing that the teeth and jaw of his fossil were just like those of an opossum1 had the same right to conclude that the pelvis would also be like an opossum's2 and so strong was his conviction that this retrospective prophecy1 about an animal which he had never seen before1 and which had been dead and buried for millions of years1 would be verified1 that he went to work upon the slab which contained the pelvis in confident expectation of finding and laying bare the 8marsupial bones10 to the satisfaction of some persons whom he had invited to witness their disinterment4 ,as he says3--8,cette opration se fit en prsence de quelques personnes qui j'en avais annonc d'avance le rsultat1 dans l'intention de leur prouver par le fait la justice de nos thories zoologiques2 puisque le vrai cachet d'une thorie est sans contredit la facult qu'elle donne de prvoir les phnomnes40 ,in the 8,ossemens fossiles0 ,cuvier leaves his paper just as it first appeared in the 8,annales du ,musum10 as 8a curious monument of the force of zoological laws and of the use which may be made of them40 ,zoological laws truly1 but not physiological laws4 ,if one sees a live dog's head1 it is extremely probable that a dog's tail is not far off1 though nobody can say why that sort of head and that sort of tail go together2 what physiological connection there is between the two4 ,so1 in the case of the ,montmartre fossil1 ,cuvier1 finding a thorough opossum's head1 concluded that the pelvis also would be like an opossum's4 ,but1 most assuredly1 the most advanced physiologist of the present day could throw no light on the question why these are associated1 nor could pretend to affirm that the existence of the one is necessarily connected with that of the other4 ,in fact1 had it so happened that the pelvis of the fossil had been originally exposed1 while the head lay hidden1 the presence of the 8marsupial bones10 however like they might have been to an opossum's1 would by no means have warranted the prediction that the skull would turn out to be that of the opossum4 ,it might just as well have been like that of some other ,marsupial2 or even like that of the totally different group of ,monotremes1 of which the only living representatives are the ,echidna and the ,ornithorhynchus4 ,for all practical purposes1 however1 the empirical laws of co-ordination of structures1 which are embodied in the generalisations of morphology1 may be confidently trusted1 if employed with due caution1 to lead to a just interpretation of fossil remains2 or1 in other words1 we may look for the verification of the retrospective prophecies which are based upon them4 ,and if this be the case1 the late advances which have been made in palontological discovery open out a new field for such prophecies4 ,for it has been ascertained with respect to many groups of animals1 that1 as we trace them back in time1 their ancestors gradually cease to exhibit those special modifications which at present characterise the type1 and more nearly embody the general plan of the group to which they belong4 ,thus1 in the well-known case of the horse1 the toes which are suppressed in the living horse are found to be more and more complete in the older members of the group1 until1 at the bottom of the ,tertiary series of ,america1 we find an equine animal which has four toes in front and three behind4 ,no remains of the horse tribe are at present known from any ,mesozoic deposit4 ,yet who can doubt that1 whenever a sufficiently extensive series of lacustrine and fluviatile beds of that age becomes known1 the lineage which has been traced thus far will be continued by equine quadrupeds with an increasing number of digits1 until the horse type merges in the five-toed form towards which these gradations point8 ,but the argument which holds good for the horse1 holds good1 not only for all mammals1 but for the whole animal world4 ,and as the study of the pedigrees1 or lines of evolution1 to which1 at present1 we have access1 brings to light1 as it assuredly will do1 the laws of that process1 we shall be able to reason from the facts with which the geological record furnishes us to those which have hitherto remained1 and many of which1 perhaps1 may for ever remain1 hidden4 ,the same method of reasoning which enables us1 when furnished with a fragment of an extinct animal1 to prophesy the character which the whole organism exhibited1 will1 sooner or later1 enable us1 when we know a few of the later terms of a genealogical series1 to predict the nature of the earlier terms4 ,in no very distant future1 the method of ,zadig1 applied to a greater body of facts than the present generation is fortunate enough to handle1 will enable the biologist to reconstruct the scheme of life from its beginning1 and to speak as confidently of the character of long extinct living beings1 no trace of which has been preserved1 as ,zadig did of the queen's spaniel and the king's horse4 ,let us hope that they may be better rewarded for their toil and their sagacity than was the ,babylonian philosopher2 for perhaps1 by that time1 the ,magi also may be reckoned among the members of a forgotten ,fauna1 extinguished in the struggle for existence against their great rival1 common sense4 ,,vii4 ,,on ,,the ,,border ,,territory ,,between ,,the ,,animal ,,and ,,the ,,vegetable ,,kingdoms4 ,in the whole history of science there is nothing more remarkable than the rapidity of the growth of biological knowledge within the last half-century1 and the extent of the modification which has thereby been effected in some of the fundamental conceptions of the naturalist4 ,in the second edition of the 8,rgne ,animal10 published in #ahbh1 ,cuvier devotes a special section to the 8,division of ,organised ,beings into ,animals and ,vegetables10 in which the question is treated with that comprehensiveness of knowledge and clear critical judgment which characterise his writings1 and justify us in regarding them as representative expressions of the most extensive1 if not the profoundest1 knowledge of his time4 ,he tells us that living beings have been subdivided from the earliest times into animated beings1 which possess sense and motion1 and inanimated beings1 which are devoid of these functions1 and simply vegetate4 ,although the roots of plants direct themselves towards moisture1 and their leaves towards air and light1--although the parts of some plants exhibit oscillating movements without any perceptible cause1 and the leaves of others retract when touched1--yet none of these movements justify the ascription to plants of perception or of will4 ,from the mobility of animals1 ,cuvier1 with his characteristic partiality for teleological reasoning1 deduces the necessity of the existence in them of an alimentary cavity1 or reservoir of food1 whence their nutrition may be drawn by the vessels1 which are a sort of internal roots2 and1 in the presence of this alimentary cavity1 he naturally sees the primary and the most important distinction between animals and plants4 ,following out his teleological argument1 ,cuvier remarks that the organisation of this cavity and its appurtenances must needs vary according to the nature of the aliment1 and the operations which it has to undergo1 before it can be converted into substances fitted for absorption2 while the atmosphere and the earth supply plants with juices ready prepared1 and which can be absorbed immediately4 ,as the animal body required to be independent of heat and of the atmosphere1 there were no means by which the motion of its fluids could be produced by internal causes4 ,hence arose the second great distinctive character of animals1 or the circulatory system1 which is less important than the digestive1 since it was unnecessary1 and therefore is absent1 in the more simple animals4 ,animals further needed muscles for locomotion and nerves for sensibility4 ,hence1 says ,cuvier1 it was necessary that the chemical composition of the animal body should be more complicated than that of the plant2 and it is so1 inasmuch as an additional substance1 nitrogen1 enters into it as an essential element2 while1 in plants1 nitrogen is only accidentally joined with the three other fundamental constituents of organic beings--carbon1 hydrogen1 and oxygen4 ,indeed1 he afterwards affirms that nitrogen is peculiar to animals2 and herein he places the third distinction between the animal and the plant4 ,the soil and the atmosphere supply plants with water1 composed of hydrogen and oxygen2 air1 consisting of nitrogen and oxygen2 and carbonic acid1 containing carbon and oxygen4 ,they retain the hydrogen and the carbon1 exhale the superfluous oxygen1 and absorb little or no nitrogen4 ,the essential character of vegetable life is the exhalation of oxygen1 which is effected through the agency of light4 ,animals1 on the contrary1 derive their nourishment either directly or indirectly from plants4 ,they get rid of the superfluous hydrogen and carbon1 and accumulate nitrogen4 ,the relations of plants and animals to the atmosphere are therefore inverse4 ,the plant withdraws water and carbonic acid from the atmosphere1 the animal contributes both to it4 ,respiration--that is1 the absorption of oxygen and the exhalation of carbonic acid--is the specially animal function of animals1 and constitutes their fourth distinctive character4 ,thus wrote ,cuvier in #ahbh4 ,but1 in the fourth and fifth decades of this century1 the greatest and most rapid revolution which biological science has ever undergone was effected by the application of the modern microscope to the investigation of organic structure2 by the introduction of exact and easily manageable methods of conducting the chemical analysis of organic compounds2 and finally1 by the employment of instruments of precision for the measurement of the physical forces which are at work in the living economy4 ,that the semi-fluid contents 7which we now term protoplasm7 of the cells of certain plants1 such as the ,char1 are in constant and regular motion1 was made out by ,bonaventura ,corti a century ago2 but the fact1 important as it was1 fell into oblivion1 and had to be rediscovered by ,treviranus in #ahjg4 ,robert ,brown noted the more complex motions of the protoplasm in the cells of ,tradescantia in #ahca2 and now such movements of the living substance of plants are well known to be some of the most widely-prevalent phenomena of vegetable life4 ,agardh1 and other of the botanists of ,cuvier's generation1 who occupied themselves with the lower plants1 had observed that1 under particular circumstances1 the contents of the cells of certain water-weeds were set free1 and moved about with considerable velocity1 and with all the appearances of spontaneity1 as locomotive bodies1 which1 from their similarity to animals of simple organisation1 were called 8zoospores40 ,even as late as #ahde1 however1 a botanist of ,schleiden's eminence dealt very sceptically with these statements2 and his scepticism was the more justified1 since ,ehrenberg1 in his elaborate and comprehensive work on the ,infusoria1 had declared the greater number of what are now recognised as locomotive plants to be animals4 ,at the present day1 innumerable plants and free plant cells are known to pass the whole or part of their lives in an actively locomotive condition1 in no wise distinguishable from that of one of the simpler animals2 and1 while in this condition1 their movements are1 to all appearance1 as spontaneous--as much the product of volition--as those of such animals4 ,hence the teleological argument for ,cuvier's first diagnostic character--the presence in animals of an alimentary cavity1 or internal pocket1 in which they can carry about their nutriment--has broken down1 so far1 at least1 as his mode of stating it goes4 ,and1 with the advance of microscopic anatomy1 the universality of the fact itself among animals has ceased to be predicable4 ,many animals of even complex structure1 which live parasitically within others1 are wholly devoid of an alimentary cavity4 ,their food is provided for them1 not only ready cooked1 but ready digested1 and the alimentary canal1 become superfluous1 has disappeared4 ,again1 the males of most ,rotifers have no digestive apparatus2 as a ,german naturalist has remarked1 they devote themselves entirely to the 8,minnedienst10 and are to be reckoned among the few realisations of the ,byronic ideal of a lover4 ,finally1 amidst the lowest forms of animal life1 the speck of gelatinous protoplasm1 which constitutes the whole body1 has no permanent digestive cavity or mouth1 but takes in its food anywhere2 and digests1 so to speak1 all over its body4 ,but although ,cuvier's leading diagnosis of the animal from the plant will not stand a strict test1 it remains one of the most constant of the distinctive characters of animals4 ,and1 if we substitute for the possession of an alimentary cavity1 the power of taking solid nutriment into the body and there digesting it1 the definition so changed will cover all animals1 except certain parasites1 and the few and exceptional cases of non-parasitic animals which do not feed at all4 ,on the other hand1 the definition thus amended will exclude all ordinary vegetable organisms4 ,cuvier himself practically gives up his second distinctive mark when he admits that it is wanting in the simpler animals4 ,the third distinction is based on a completely erroneous conception of the chemical differences and resemblances between the constituents of animal and vegetable organisms1 for which ,cuvier is not responsible1 as it was current among contemporary chemists4 ,it is now established that nitrogen is as essential a constituent of vegetable as of animal living matter2 and that the latter is1 chemically speaking1 just as complicated as the former4 ,starchy substances1 cellulose and sugar1 once supposed to be exclusively confined to plants1 are now known to be regular and normal products of animals4 ,amylaceous and saccharine substances are largely manufactured1 even by the highest animals2 cellulose is widespread as a constituent of the skeletons of the lower animals2 and it is probable that amyloid substances are universally present in the animal organism1 though not in the precise form of starch4 ,moreover1 although it remains true that there is an inverse relation between the green plant in sunshine and the animal1 in so far as1 under these circumstances1 the green plant decomposes carbonic acid and exhales oxygen1 while the animal absorbs oxygen and exhales carbonic acid2 yet1 the exact researches of the modern chemical investigators of the physiological processes of plants have clearly demonstrated the fallacy of attempting to draw any general distinction between animals and vegetables on this ground4 ,in fact1 the difference vanishes with the sunshine1 even in the case of the green plant2 which1 in the dark1 absorbs oxygen and gives out carbonic acid like any animal4#cj ,on the other hand1 those plants1 such as the fungi1 which contain no chlorophyll and are not green1 are always1 so far as respiration is concerned1 in the exact position of animals4 ,they absorb oxygen and give out carbonic acid4 ,thus1 by the progress of knowledge1 ,cuvier's fourth distinction between the animal and the plant has been as completely invalidated as the third and second2 and even the first can be retained only in a modified form and subject to exceptions4 ,but has the advance of biology simply tended to break down old distinctions1 without establishing new ones8 ,with a qualification1 to be considered presently1 the answer to this question is undoubtedly in the affirmative4 ,the famous researches of ,schwann and ,schleiden in #ahcg and the following years1 founded the modern science of histology1 or that branch of anatomy which deals with the ultimate visible structure of organisms1 as revealed by the microscope2 and1 from that day to this1 the rapid improvement of methods of investigation1 and the energy of a host of accurate observers1 have given greater and greater breadth and firmness to ,schwann's great generalisation1 that a fundamental unity of structure obtains in animals and plants2 and that1 however diverse may be the fabrics1 or tissues1 of which their bodies are composed1 all these varied structures result from the metamorphosis of morphological units 7termed cells1 in a more general sense than that in which the word 8cells0 was at first employed71 which are not only similar in animals and in plants respectively1 but present a close resemblance1 when those of animals and those of plants are compared together4 ,the contractility which is the fundamental condition of locomotion1 has not only been discovered to exist far more widely among plants than was formerly imagined2 but1 in plants1 the act of contraction has been found to be accompanied1 as ,dr4 ,burdon ,sanderson's interesting investigations have shown1 by a disturbance of the electrical state of the contractile substance1 comparable to that which was found by ,du ,bois ,reymond to be a concomitant of the activity of ordinary muscle in animals4 ,again1 ,i know of no test by which the reaction of the leaves of the ,sundew and of other plants to stimuli1 so fully and carefully studied by ,mr4 ,darwin1 can be distinguished from those acts of contraction following upon stimuli1 which are called 8reflex0 in animals4 ,on each lobe of the bilobed leaf of ,venus's fly trap 7,diona muscipula7 are three delicate filaments which stand out at right angle from the surface of the leaf4 ,touch one of them with the end of a fine human hair and the lobes of the leaf instantly close together#ca in virtue of an act of contraction of part of their substance1 just as the body of a snail contracts into its shell when one of its 8horns0 is irritated4 ,the reflex action of the snail is the result of the presence of a nervous system in the animal4 ,a molecular change takes place in the nerve of the tentacle1 is propagated to the muscles by which the body is retracted1 and causing them to contract1 the act of retraction is brought about4 ,of course the similarity of the acts does not necessarily involve the conclusion that the mechanism by which they are effected is the same2 but it suggests a suspicion of their identity which needs careful testing4 ,the results of recent inquiries into the structure of the nervous system of animals converge towards the conclusion that the nerve fibres1 which we have hitherto regarded as ultimate elements of nervous tissue1 are not such1 but are simply the visible aggregations of vastly more attenuated filaments1 the diameter of which dwindles down to the limits of our present microscopic vision1 greatly as these have been extended by modern improvements of the microscope2 and that a nerve is1 in its essence1 nothing but a linear tract of specially modified protoplasm between two points of an organism--one of which is able to affect the other by means of the communication so established4 ,hence1 it is conceivable that even the simplest living being may possess a nervous system4 ,and the question whether plants are provided with a nervous system or not1 thus acquires a new aspect1 and presents the histologist and physiologist with a problem of extreme difficulty1 which must be attacked from a new point of view and by the aid of methods which have yet to be invented4 ,thus it must be admitted that plants may be contractile and locomotive2 that1 while locomotive1 their movements may have as much appearance of spontaneity as those of the lowest animals2 and that many exhibit actions1 comparable to those which are brought about by the agency of a nervous system in animals4 ,and it must be allowed to be possible that further research may reveal the existence of something comparable to a nervous system in plants4 ,so that ,i know not where we can hope to find any absolute distinction between animals and plants1 unless we return to their mode of nutrition1 and inquire whether certain differences of a more occult character than those imagined to exist by ,cuvier1 and which certainly hold good for the vast majority of animals and plants1 are of universal application4 ,a bean may be supplied with water in which salts of ammonia and certain other mineral salts are dissolved in due proportion2 with atmospheric air containing its ordinary minute dose of carbonic acid2 and with nothing else but sunlight and heat4 ,under these circumstances1 unnatural as they are1 with proper management1 the bean will thrust forth its radicle and its plumule2 the former will grow down into roots1 the latter grow up into the stem and leaves of a vigorous bean plant2 and this plant will1 in due time1 flower and produce its crop of beans1 just as if it were grown in the garden or in the field4 ,the weight of the nitrogenous protein compounds1 of the oily1 starchy1 saccharine and woody substances contained in the full-grown plant and its seeds1 will be vastly greater than the weight of the same substances contained in the bean from which it sprang4 ,but nothing has been supplied to the bean save water1 carbonic acid1 ammonia1 potash1 lime1 iron1 and the like1 in combination with phosphoric1 sulphuric1 and other acids4 ,neither protein1 nor fat1 nor starch1 nor sugar1 nor any substance in the slightest degree resembling them1 has formed part of the food of the bean4 ,but the weights of the carbon1 hydrogen1 oxygen1 nitrogen1 phosphorus1 sulphur1 and other elementary bodies contained in the bean-plant1 and in the seeds which it produces1 are exactly equivalent to the weights of the same elements which have disappeared from the materials supplied to the bean during its growth4 ,whence it follows that the bean has taken in only the raw materials of its fabric1 and has manufactured them into bean stuffs4 ,the bean has been able to perform this great chemical feat by the help of its green colouring matter1 or chlorophyll2 for it is only the green parts of the plant which1 under the influence of sunlight1 have the marvellous power of decomposing carbonic acid1 setting free the oxygen and laying hold of the carbon which it contains4 ,in fact1 the bean obtains two of the absolutely indispensable elements of its substance from two distinct sources2 the watery solution1 in which its roots are plunged1 contains nitrogen but no carbon2 the air1 to which the leaves are exposed1 contains carbon1 but its nitrogen is in the state of a free gas1 in which condition the bean can make no use of it2#cb and the chlorophyll#cc is the apparatus by which the carbon is extracted from the atmospheric carbonic acid--the leaves being the chief laboratories in which this operation is effected4 ,the great majority of conspicuous plants are1 as everybody knows1 green2 and this arises from the abundance of their chlorophyll4 ,the few which contain no chlorophyll and are colourless1 are unable to extract the carbon which they require from atmospheric carbonic acid1 and lead a parasitic existence upon other plants2 but it by no means follows1 often as the statement has been repeated1 that the manufacturing power of plants depends on their chlorophyll1 and its interaction with the rays of the sun4 ,on the contrary1 it is easily demonstrated1 as ,pasteur first proved1 that the lowest fungi1 devoid of chlorophyll1 or of any substitute for it1 as they are1 nevertheless possess the characteristic manufacturing powers of plants in a very high degree4 ,only it is necessary that they should be supplied with a different kind of raw material2 as they cannot extract carbon from carbonic acid1 they must be furnished with something else that contains carbon4 ,tartaric acid is such a substance2 and if a single spore of the commonest and most troublesome of moulds--,penicillium--be sown in a saucerful of water1 in which tartrate of ammonia1 with a small percentage of phosphates and sulphates is contained1 and kept warm1 whether in the dark or exposed to light1 it will1 in a short time1 give rise to a thick crust of mould1 which contains many million times the weight of the original spore1 in protein compounds and cellulose4 ,thus we have a very wide basis of fact for the generalisation that plants are essentially characterised by their manufacturing capacity--by their power of working up mere mineral matters into complex organic compounds4 ,contrariwise1 there is a no less wide foundation for the generalisation that animals1 as ,cuvier puts it1 depend directly or indirectly upon plants for the materials of their bodies2 that is1 either they are herbivorous1 or they eat other animals which are herbivorous4 ,but for what constituents of their bodies are animals thus dependent upon plants8 ,certainly not for their horny matter2 nor for chondrin1 the proximate chemical element of cartilage2 nor for gelatine2 nor for syntonin1 the constituent of muscle2 nor for their nervous or biliary substances2 nor for their amyloid matters2 nor1 necessarily1 for their fats4 ,it can be experimentally demonstrated that animals can make these for themselves4 ,but that which they cannot make1 but must1 in all known cases1 obtain directly or indirectly from plants1 is the peculiar nitrogenous matter1 protein4 ,thus the plant is the ideal proltaire of the living world1 the worker who produces2 the animal1 the ideal aristocrat1 who mostly occupies himself in consuming1 after the manner of that noble representative of the line of ,zhdarm1 whose epitaph is written in ,sartor ,resartus4 ,here is our last hope of finding a sharp line of demarcation between plants and animals2 for1 as ,i have already hinted1 there is a border territory between the two kingdoms1 a sort of no-man's-land1 the inhabitants of which certainly cannot be discriminated and brought to their proper allegiance in any other way4 ,some months ago1 ,professor ,tyndall asked me to examine a drop of infusion of hay1 placed under an excellent and powerful microscope1 and to tell him what ,i thought some organisms visible in it were4 ,i looked and observed1 in the first place1 multitudes of ,bacteria moving about with their ordinary intermittent spasmodic wriggles4 ,as to the vegetable nature of these there is now no doubt4 ,not only does the close resemblance of the ,bacteria to unquestionable plants1 such as the ,oscillatori1 and lower forms of ,fungi1 justify this conclusion1 but the manufacturing test settles the question at once4 ,it is only needful to add a minute drop of fluid containing ,bacteria1 to water in which tartrate1 phosphate1 and sulphate of ammonia are dissolved2 and1 in a very short space of time1 the clear fluid becomes milky by reason of their prodigious multiplication1 which1 of course1 implies the manufacture of living ,bacterium-stuff out of these merely saline matters4 ,but other active organisms1 very much larger than the ,bacteria1 attaining in fact the comparatively gigantic dimensions of #a_/cjjj of an inch or more1 incessantly crossed the field of view4 ,each of these had a body shaped like a pear1 the small end being slightly incurved and produced into a long curved filament1 or cilium1 of extreme tenuity4 ,behind this1 from the concave side of the incurvation1 proceeded another long cilium1 so delicate as to be discernible only by the use of the highest powers and careful management of the light4 ,in the centre of the pear-shaped body a clear round space could occasionally be discerned1 but not always2 and careful watching showed that this clear vacuity appeared gradually1 and then shut up and disappeared suddenly1 at regular intervals4 ,such a structure is of common occurrence among the lowest plants and animals1 and is known as a contractile vacuole4 ,the little creature thus described sometimes propelled itself with great activity1 with a curious rolling motion1 by the lashing of the front cilium1 while the second cilium trailed behind2 sometimes it anchored itself by the hinder cilium and was spun round by the working of the other1 its motions resembling those of an anchor buoy in a heavy sea4 ,sometimes1 when two were in full career towards one another1 each would appear dexterously to get out of the other's way2 sometimes a crowd would assemble and jostle one another1 with as much semblance of individual effort as a spectator on the ,grands ,mulets might observe with a telescope among the specks representing men in the valley of ,chamounix4 ,the spectacle1 though always surprising1 was not new to me4 ,so my reply to the question put to me was1 that these organisms were what biologists call ,monads1 and though they might be animals1 it was also possible that they might1 like the ,bacteria1 be plants4 ,my friend received my verdict with an expression which showed a sad want of respect for authority4 ,he would as soon believe that a sheep was a plant4 ,naturally piqued by this want of faith1 ,i have thought a good deal over the matter2 and as ,i still rest in the lame conclusion ,i originally expressed1 and must even now confess that ,i cannot certainly say whether this creature is an animal or a plant1 ,i think it may be well to state the grounds of my hesitation at length4 ,but1 in the first place1 in order that ,i may conveniently distinguish this 8,monad0 from the multitude of other things which go by the same designation1 ,i must give it a name of its own4 ,i think 7though1 for reasons which need not be stated at present1 ,i am not quite sure7 that it is identical with the species ,monas lens1 as defined by the eminent ,french microscopist ,dujardin1 though his magnifying power was probably insufficient to enable him to see that it is curiously like a much larger form of monad which he has named ,heteromita4 ,i shall1 therefore1 call it not ,monas1 but ,heteromita lens4 ,i have been unable to devote to my ,heteromita the prolonged study needful to work out its whole history1 which would involve weeks1 or it may be months1 of unremitting attention4 ,but ,i the less regret this circumstance1 as some remarkable observations recently published by ,messrs4 ,dallinger and ,drysdale#cd on certain ,monads1 relate1 in part1 to a form so similar to my ,heteromita lens1 that the history of the one may be used to illustrate that of the other4 ,these most patient and painstaking observers1 who employed the highest attainable powers of the microscope and1 relieving one another1 kept watch day and night over the same individual monads1 have been enabled to trace out the whole history of their ,heteromita2 which they found in infusions of the heads of fishes of the ,cod tribe4 ,of the four monads described and figured by these investigators1 one1 as ,i have said1 very closely resembles ,heteromita lens in every particular1 except that it has a separately distinguishable central particle or 8nucleus10 which is not certainly to be made out in ,heteromita lens2 and that nothing is said by ,messrs4 ,dallinger and ,drysdale of the existence of a contractile vacuole in this monad1 though they describe it in another4 ,their ,heteromita1 however1 multiplied rapidly by fission4 ,sometimes a transverse constriction appeared2 the hinder half developed a new cilium1 and the hinder cilium gradually split from its base to its free end1 until it was divided into two2 a process which1 considering the fact that this fine filament cannot be much more than #a_/ajjjjj of an inch in diameter1 is wonderful enough4 ,the constriction of the body extended inwards until the two portions were united by a narrow isthmus2 finally1 they separated and each swam away by itself1 a complete ,heteromita1 provided with its two cilia4 ,sometimes the constriction took a longitudinal direction1 with the same ultimate result4 ,in each case the process occupied not more than six or seven minutes4 ,at this rate1 a single ,heteromita would give rise to a thousand like itself in the course of an hour1 to about a million in two hours1 and to a number greater than the generally assumed number of human beings now living in the world in three hours2 or1 if we give each ,heteromita an hour's enjoyment of individual existence1 the same result will be obtained in about a day4 ,the apparent suddenness of the appearance of multitudes of such organisms as these1 in any nutritive fluid to which one obtains access1 is thus easily explained4 ,during these processes of multiplication by fission1 the ,heteromita remains active2 but sometimes another mode of fission occurs4 ,the body becomes rounded and quiescent1 or nearly so2 and1 while in this resting state1 divides into two portions1 each of which is rapidly converted into an active ,heteromita4 ,a still more remarkable phenomenon is that kind of multiplication which is preceded by the union of two monads1 by a process which is termed conjugation4 ,two active ,heteromit become applied to one another1 and then slowly and gradually coalesce into one body4 ,the two nuclei run into one2 and the mass resulting from the conjugation of the two ,heteromit1 thus fused together1 has a triangular form4 ,the two pairs of cilia are to be seen1 for some time1 at two of the angles1 which answer to the small ends of the conjoined monads2 but they ultimately vanish1 and the twin organism1 in which all visible traces of organisation have disappeared1 falls into a state of rest4 ,sudden wave-like movements of its substance next occur2 and1 in a short time1 the apices of the triangular mass burst1 and give exit to a dense yellowish1 glairy fluid1 filled with minute granules4 ,this process1 which1 it will be observed1 involves the actual confluence and mixture of the substance of two distinct organisms1 is effected in the space of about two hours4 ,the authors whom ,i quote say that they 8cannot express0 the excessive minuteness of the granules in question1 and they estimate their diameter at less than #a_/bjjjjj of an inch4 ,under the highest powers of the microscope at present applicable such specks are hardly discernible4 ,nevertheless1 particles of this size are massive when compared to physical molecules2 whence there is no reason to doubt that each1 small as it is1 may have a molecular structure sufficiently complex to give rise to the phenomena of life4 ,and1 as a matter of fact1 by patient watching of the place at which these infinitesimal living particles were discharged1 our observers assured themselves of their growth and development into new monads4 ,these1 in about four hours from their being set free1 had attained a sixth of the length of the parent1 with the characteristic cilia1 though at first they were quite motionless2 and1 in four hours more1 they had attained the dimensions and exhibited all the activity of the adult4 ,these inconceivably minute particles are therefore the germs of the ,heteromita2 and from the dimensions of these germs it is easily shown that the body formed by conjugation may1 at a low estimate1 have given exit to thirty thousand of them2 a result of a matrimonial process whereby the contracting parties1 without a metaphor1 8become one flesh10 enough to make a ,malthusian despair of the future of the ,universe4 ,i am not aware that the investigators from whom ,i have borrowed this history have endeavoured to ascertain whether their monads take solid nutriment or not2 so that though they help us very much to fill up the blanks in the history of my ,heteromita1 their observations throw no light on the problem we are trying to solve--,is it an animal or is it a plant8 ,undoubtedly it is possible to bring forward very strong arguments in favour of regarding ,heteromita as a plant4 ,for example1 there is a ,fungus1 an obscure and almost microscopic mould1 termed ,peronospora infestans4 ,like many other ,fungi1 the ,peronospor are parasitic upon other plants2 and this particular ,peronospora happens to have attained much notoriety and political importance1 in a way not without a parallel in the career of notorious politicians1 namely1 by reason of the frightful mischief it has done to mankind4 ,for it is this ,fungus which is the cause of the potato disease2 and1 therefore1 ,peronospora infestans 7doubtless of exclusively ,saxon origin1 though not accurately known to be so7 brought about the ,irish famine4 ,the plants afflicted with the malady are found to be infested by a mould1 consisting of fine tubular filaments1 termed hyph1 which burrow through the substance of the potato plant1 and appropriate to themselves the substance of their host2 while1 at the same time1 directly or indirectly1 they set up chemical changes by which even its woody framework becomes blackened1 sodden1 and withered4 ,in structure1 however1 the ,peronospora is as much a mould as the common ,penicillium2 and just as the ,penicillium multiplies by the breaking up of its hyph into separate rounded bodies1 the spores2 so1 in the ,peronospora1 certain of the hyph grow out into the air through the interstices of the superficial cells of the potato plant1 and develop spores4 ,each of these hyph usually gives off several branches4 ,the ends of the branches dilate and become closed sacs1 which eventually drop off as spores4 ,the spores falling on some part of the same potato plant1 or carried by the wind to another1 may at once germinate1 throwing out tubular prolongations which become hyph1 and burrow into the substance of the plant attacked4 ,but1 more commonly1 the contents of the spore divide into six or eight separate portions4 ,the coat of the spore gives way1 and each portion then emerges as an independent organism1 which has the shape of a bean1 rather narrower at one end than the other1 convex on one side1 and depressed or concave on the opposite4 ,from the depression1 two long and delicate cilia proceed1 one shorter than the other1 and directed forwards4 ,close to the origin of these cilia1 in the substance of the body1 is a regularly pulsating1 contractile vacuole4 ,the shorter cilium vibrates actively1 and effects the locomotion of the organism1 while the other trails behind2 the whole body rolling on its axis with its pointed end forwards4 ,the eminent botanist1 ,de ,bary1 who was not thinking of our problem1 tells us1 in describing the movements of these 8,zoospores10 that1 as they swim about1 8,foreign bodies are carefully avoided1 and the whole movement has a deceptive likeness to the voluntary changes of place which are observed in microscopic animals40 ,after swarming about in this way in the moisture on the surface of a leaf or stem 7which1 film though it may be1 is an ocean to such a fish7 for half an hour1 more or less1 the movement of the zoospore becomes slower1 and is limited to a slow turning upon its axis1 without change of place4 ,it then becomes quite quiet1 the cilia disappear1 it assumes a spherical form1 and surrounds itself with a distinct1 though delicate1 membranous coat4 ,a protuberance then grows out from one side of the sphere1 and rapidly increasing in length1 assumes the character of a hypha4 ,the latter penetrates into the substance of the potato plant1 either by entering a stomate1 or by boring through the wall of an epidermic cell1 and ramifies1 as a mycelium1 in the substance of the plant1 destroying the tissues with which it comes in contact4 ,as these processes of multiplication take place very rapidly1 millions of spores are soon set free from a single infested plant2 and1 from their minuteness1 they are readily transported by the gentlest breeze4 ,since1 again1 the zoospores set free from each spore1 in virtue of their powers of locomotion1 swiftly disperse themselves over the surface1 it is no wonder that the infection1 once started1 soon spreads from field to field1 and extends its ravages over a whole country4 ,however1 it does not enter into my present plan to treat of the potato disease1 instructively as its history bears upon that of other epidemics2 and ,i have selected the case of the ,peronospora simply because it affords an example of an organism1 which1 in one stage of its existence1 is truly a 8,monad10 indistinguishable by any important character from our ,heteromita1 and extraordinarily like it in some respects4 ,and yet this 8,monad0 can be traced1 step by step1 through the series of metamorphoses which ,i have described1 until it assumes the features of an organism1 which is as much a plant as is an oak or an elm4 ,moreover1 it would be possible to pursue the analogy farther4 ,under certain circumstances1 a process of conjugation takes place in the ,peronospora4 ,two separate portions of its protoplasm become fused together1 surround themselves with a thick coat1 and give rise to a sort of vegetable egg called an oospore4 ,after a period of rest1 the contents of the oospore break up into a number of zoospores like those already described1 each of which1 after a period of activity1 germinates in the ordinary way4 ,this process obviously corresponds with the conjugation and subsequent setting free of germs in the ,heteromita4 ,but it may be said that the ,peronospora is1 after all1 a questionable sort of plant2 that it seems to be wanting in the manufacturing power1 selected as the main distinctive character of vegetable life2 or1 at any rate1 that there is no proof that it does not get its protein matter ready made from the potato plant4 ,let us1 therefore1 take a case which is not open to these objections4 ,there are some small plants known to botanists as members of the genus ,coleochte1 which1 without being truly parasitic1 grow upon certain water-weeds1 as lichens grow upon trees4 ,the little plant has the form of an elegant green star1 the branching arms of which are divided into cells4 ,its greenness is due to its chlorophyll1 and it undoubtedly has the manufacturing power in full degree1 decomposing carbonic acid and setting oxygen free1 under the influence of sunlight4 ,but the protoplasmic contents of some of the cells of which the plant is made up occasionally divide1 by a method similar to that which effects the division of the contents of the ,peronospora spore2 and the severed portions are then set free as active monad-like zoospores4 ,each is oval and is provided at one extremity with two long active cilia4 ,propelled by these1 it swims about for a longer or shorter time1 but at length comes to a state of rest and gradually grows into a ,coleochte4 ,moreover1 as in the ,peronospora1 conjugation may take place and result in an oospore2 the contents of which divide and are set free as monadiform germs4 ,if the whole history of the zoospores of ,peronospora1 and of ,coleochte were unknown1 they would undoubtedly be classed among 8,monads0 with the same right as ,heteromita2 why then may not ,heteromita be a plant1 even though the cycle of forms through which it passes shows no terms quite so complex as those which occur in ,peronospora and ,coleochte8 ,and1 in fact1 there are some green organisms1 in every respect characteristically plants1 such as ,chlamydomonas1 and the common ,volvox1 or so-called 8,globe animalcule10 which run through a cycle of forms of just the same simple character as those of ,heteromita4 ,the name of ,chlamydomonas is applied to certain microscopic green bodies1 each of which consists of a protoplasmic central substance invested by a structureless sac4 ,the latter contains cellulose1 as in ordinary plants2 and the chlorophyll which gives the green colour enables the ,chlamydomonas to decompose carbonic acid and fix carbon as they do4 ,two long cilia protrude through the cell-wall1 and effect the rapid locomotion of this 8monad10 which1 in all respects except its mobility1 is characteristically a plant4 ,under ordinary circumstances1 the ,chlamydomonas multiplies by simple fission1 each splitting into two or into four parts1 which separate and become independent organisms4 ,sometimes1 however1 the ,chlamydomonas divides into eight parts1 each of which is provided with four instead of two cilia4 ,these 8zoospores0 conjugate in pairs1 and give rise to quiescent bodies1 which multiply by division1 and eventually pass into the active state4 ,thus1 so far as outward form and the general character of the cycle of modifications1 through which the organism passes in the course of its life1 are concerned1 the resemblance between ,chlamydomonas and ,heteromita is of the closest description4 ,and on the face of the matter there is no ground for refusing to admit that ,heteromita may be related to ,chlamydomonas1 as the colourless fungus is to the green alga4 ,volvox may be compared to a hollow sphere1 the wall of which is made up of coherent ,chlamydomonads2 and which progresses with a rotating motion effected by the paddling of the multitudinous pairs of cilia which project from its surface4 ,each ,volvoxmonad1 moreover1 possesses a red pigment spot1 like the simplest form of eye known among animals4 ,the methods of fissive multiplication and of conjugation observed in the monads of this locomotive globe are essentially similar to those observed in ,chlamydomonas2 and1 though a hard battle has been fought over it1 ,volvox is now finally surrendered to the ,botanists4 ,thus there is really no reason why ,heteromita may not be a plant2 and this conclusion would be very satisfactory1 if it were not equally easy to show that there is really no reason why it should not be an animal4 ,for there are numerous organisms presenting the closest resemblance to ,heteromita1 and1 like it1 grouped under the general name of 8,monads10 which1 nevertheless1 can be observed to take in solid nutriment1 and which1 therefore1 have a virtual1 if not an actual1 mouth and digestive cavity1 and thus come under ,cuvier's definition of an animal4 ,numerous forms of such animals have been described by ,ehrenberg1 ,dujardin1 ,h4 ,james ,clark1 and other writers on the ,infusoria4 ,indeed1 in another infusion of hay in which my ,heteromita lens occurred1 there were innumerable infusorial animalcules belonging to the well-known species ,colpoda cucullus4#ce ,full-sized specimens of this animalcule attain a length of between #a_/cjj or #a_/djj of an inch1 so that it may have ten times the length and a thousand times the mass of a ,heteromita4 ,in shape1 it is not altogether unlike ,heteromita4 ,the small end1 however1 is not produced into one long cilium1 but the general surface of the body is covered with small actively vibrating ciliary organs1 which are only longest at the small end4 ,at the point which answers to that from which the two cilia arise in ,heteromita1 there is a conical depression1 the mouth2 and1 in young specimens1 a tapering filament1 which reminds one of the posterior cilium of ,heteromita1 projects from this region4 ,the body consists of a soft granular protoplasmic substance1 the middle of which is occupied by a large oval mass called the 8nucleus20 while1 at its hinder end1 is a 8contractile vacuole10 conspicuous by its regular rhythmic appearances and disappearances4 ,obviously1 although the ,colpoda is not a monad1 it differs from one only in subordinate details4 ,moreover1 under certain conditions1 it becomes quiescent1 incloses itself in a delicate case or cyst1 and then divides into two1 four1 or more portions1 which are eventually set free and swim about as active ,colpod4 ,but this creature is an unmistakable animal1 and full-sized ,colpod may be fed as easily as one feeds chickens4 ,it is only needful to diffuse very finely ground carmine through the water in which they live1 and1 in a very short time1 the bodies of the ,colpod are stuffed with the deeply-coloured granules of the pigment4 ,and if this were not sufficient evidence of the animality of ,colpoda1 there comes the fact that it is even more similar to another well-known animalcule1 ,paramcium1 than it is to a monad4 ,but ,paramcium is so huge a creature compared with those hitherto discussed--it reaches #a_/abj of an inch or more in length--that there is no difficulty in making out its organisation in detail2 and in proving that it is not only an animal1 but that it is an animal which possesses a somewhat complicated organisation4 ,for example1 the surface layer of its body is different in structure from the deeper parts4 ,there are two contractile vacuoles1 from each of which radiates a system of vessel-like canals2 and not only is there a conical depression continuous with a tube1 which serve as mouth and gullet1 but the food ingested takes a definite course1 and refuse is rejected from a definite region4 ,nothing is easier than to feed these animals1 and to watch the particles of indigo or carmine accumulate at the lower end of the gullet4 ,from this they gradually project1 surrounded by a ball of water1 which at length passes with a jerk1 oddly simulating a gulp1 into the pulpy central substance of the body1 there to circulate up one side and down the other1 until its contents are digested and assimilated4 ,nevertheless1 this complex animal multiplies by division1 as the monad does1 and1 like the monad1 undergoes conjugation4 ,it stands in the same relation to ,heteromita on the animal side1 as ,coleochte does on the plant side4 ,start from either1 and such an insensible series of gradations leads to the monad that it is impossible to say at any stage of the progress--here the line between the animal and the plant must be drawn4 ,there is reason to think that certain organisms which pass through a monad stage of existence1 such as the ,myxomycetes1 are1 at one time of their lives1 dependent upon external sources for their protein matter1 or are animals2 and1 at another period1 manufacture it1 or are plants4 ,and seeing that the whole progress of modern investigation is in favour of the doctrine of continuity1 it is a fair and probable speculation--though only a speculation--that1 as there are some plants which can manufacture protein out of such apparently intractable mineral matters as carbonic acid1 water1 nitrate of ammonia1 metallic and earthy salts2 while others need to be supplied with their carbon and nitrogen in the somewhat less raw form of tartrate of ammonia and allied compounds2 so there may be yet others1 as is possibly the case with the true parasitic plants1 which can only manage to put together materials still better prepared--still more nearly approximated to protein--until we arrive at such organisms as the ,psorospermi and the ,panhistophyton1 which are as much animal as vegetable in structure1 but are animal in their dependence on other organisms for their food4 ,the singular circumstance observed by ,meyer1 that the ,torula of yeast1 though an indubitable plant1 still flourishes most vigorously when supplied with the complex nitrogenous substance1 pepsin2 the probability that the ,peronospora is nourished directly by the protoplasm of the potato-plant2 and the wonderful facts which have recently been brought to light respecting insectivorous plants1 all favour this view2 and tend to the conclusion that the difference between animal and plant is one of degree rather than of kind2 and that the problem whether1 in a given case1 an organism is an animal or a plant1 may be essentially insoluble4 ,,viii4 ,,on ,,certain ,,errors ,,respecting ,,the ,,structure ,,of ,,the ,,heart ,,attributed ,,to ,,aristotle4 ,in all the commentaries upon the 8,historia ,animalium0 which ,i have met with1 ,aristotle's express and repeated statement1 that the heart of man and the largest animals contains only three cavities1 is noted as a remarkable error4 ,even ,cuvier1 who had a great advantage over most of the commentators in his familiarity with the subject of ,aristotle's description1 and whose habitual caution and moderation seem to desert him when the opportunity of panegyrising the philosopher presents itself1 is betrayed into something like a sneer on this topic4 8,du reste il n'attribue cet organe que trois cavits1 erreur qui prouve au moins qu'il en avait regard la structure40#cf ,to which remark1 what follows will1 ,i think1 justify the reply1 that it 8prouve au moins0 that ,cuvier had not given ordinary attention1 to say nothing of the careful study which they deserve1 to sundry passages in the first and the third books of the 8,historia0 which ,i proceed to lay before the reader4 ,for convenience of reference these passages are marked ,a1 ,b1 ,c1 etc4#cg ,book i4 #ag4--7;,a7 8,the heart has three cavities1 it lies above the lung on the division of the windpipe1 and has a fatty and thick membrane where it is united with the great vein and the aorta4 ,it lies upon the aorta1 with its point down the chest1 in all animals that have a chest4 ,in all1 alike in those that have a chest and in those that have none1 the foremost part of it is the apex4 ,this is often overlooked through the turning upside down of the dissection4 ,the rounded end of the heart is uppermost1 the pointed end of it is largely fleshy and thick1 and in its cavities there are tendons4 ,in other animals which have a chest the heart lies in the middle of the chest2 in men1 more to the left side1 between the nipples1 a little inclined to the left nipple in the upper part of the chest4 ,the heart is not large1 and its general form is not elongated but rounded1 except that the apex is produced into a point4 7,b7 8,it has1 as already stated1 three cavities1 the largest of them is on the right1 the smallest on the left1 the middle-sized one in the middle2 they have all1 also the two small ones1 passages 77 towards the lung1 very evidently as respects one of the cavities4 ,in the region of the union with the great vein and the aorta the largest cavity is connected with the largest vein 7near which is the mesentery72 the middle cavity with the aorta4 7,c7 8,canals 77 from the heart pass to the lung and divide in the same fashion as the windpipe does1 closely accompanying those from the windpipe through the whole lung4 ,the canals from the heart are uppermost4 7,d7 8,no canal is common to the branches of the windpipe and those of the vein 7 ' 7 but through those parts of them which are in contact 7 7 the air passes in and they the carry it to the heart4 7,e7 8,one of the canals leads to the right cavity1 the other to the left4 7,f7 8,of all the viscera1 the heart alone contains blood in itself4 ,the lung contains blood1 not in itself but in the veins1 the heart in itself2 for in each of the cavities there is blood2 the thinnest is in the middle cavity40 ,book iii4 #c4--7;,g7 8,two veins lie in the thorax alongside the spine1 on its inner face2 the larger more forwards1 the smaller behind2 the larger more to the right1 the smaller1 which some call aorta 7on account of the tendinous part of it seen in dead bodies71 to the left4 ,these take their origin from the heart2 they pass entire1 preserving the nature of veins1 through the other viscera that they reach2 while the heart is rather a part of them1 and more especially of the anterior and larger one1 which is continued into veins above and below1 while between these is the heart4 7,h7 8,all hearts contain cavities1 but1 in those of very small animals1 the largest cavity is hardly visible1 those of middling size have another1 and the biggest all three4 7,i7 8,the point of the heart is directed forwards1 as was mentioned at first2 the largest cavity to the right and upper side of it1 the smallest to the left1 and the middle-sized one between these2 both of these are much smaller than the largest4 7,k7 8,they are all connected by passages 77 with the lung1 but1 on account of the smallness of the canals1 this is obscure except in one4 7,l7 8,the great vein proceeds from the largest cavity which lies upwards and to the right2 next through the hollow middle part 7 7 it becomes vein again1 this cavity being a part of the vein in which the blood stagnates4 7,m7 8,the aorta proceeds from the middle cavity1 but not in the same way1 for it is connected with the middle cavity by a much more narrow tube 774 7,n7 8,the great vein extends through the heart1 towards the aorta from the heart4 7,o7 8,the great vein is membranous like skin1 the aorta narrower than it and very tendinous1 and as it extends towards the head and the lower parts it becomes narrow and altogether tendinous4 7,p7 8,in the first place1 a part of the great vein extends upwards from the heart towards the lung and the attachment of the aorta1 the vein being large and undivided4 ,it divides into two parts1 the one to the lung1 the other to the spine and the lowest vertebra of the neck4 7,q7 8,the vein which extends to the lung first divides into two parts for the two halves of it and then extends alongside each tube 77 and each passage 771 the larger beside the larger and the smaller beside the smaller1 so that no part of the lung can be found from which a passage 77 and a vein are absent4 ,the terminations are invisible on account of their minuteness1 but the whole lung appears full of blood4 ,the canals from the vein lie above the tubes given off from the windpipe40 ,the key to the whole of the foregoing description of the heart lies in the passages 7,g7 and 7,l74 ,they prove that ,aristotle1 like ,galen1 five hundred years afterwards1 and like the great majority of the old ,greek anatomists1 did not reckon what we call the right auricle as a constituent of the heart at all1 but as a hollow part1 or dilatation1 of the 8great vein40 ,aristotle is careful to state that his observations were conducted on suffocated animals2 and if any one will lay open the thorax of a dog or a rabbit1 which has been killed with chloroform1 in such a manner as to avoid wounding any important vessel1 he will at once see why ,aristotle adopted this view4 ,for1 as the subjoined figure 7p4 #ahe7 shows1 the vena cava inferior 7b71 the right auricle 7,r4a471 and the vena cava superior and innominate vein 7,v4,i47 distended with blood seem to form one continuous column1 to which the heart is attached as a sort of appendage4 ,this column is1 as ,aristotle says1 vein above 7a7 and vein below 7b71 the upper and the lower divisions being connected --or by means of the intervening cavity or chamber 7,r4a47--which is that which we call the right auricle4 ,illustration3 ,a dog having been killed by chloroform1 enough of the right wall of the thorax was removed1 without any notable bleeding1 to expose the thoracic viscera4 ,a carefully measured outline sketch of the parts in situ was then made1 and on dissection1 twenty-four hours afterwards1 the necessary anatomical details were added4 ,the woodcut is a faithfully reduced copy of the drawing thus constructed2 and it represents the relations of the heart and great vessels as ,aristotle saw them in a suffocated animal4 ,all but the inner lobe of the right lung has been removed2 as well as the right half of the pericardium and the right walls of the right auricle and ventricle4 ,it must be remembered that the thin transparent pericardial membrane appears nothing like so distinct in nature4 a4b41 ,aristotle's 8great vein02 ,v4,i41 right vena innominata and vena cava superior2 b1 the inferior vena cava2 ,r4a41 the 8hollow middle0 part of the great vein or the right auricle2 ,r4v1 the prolongation of the cavity of the right ventricle ,r4v towards the pulmonary artery2 tr1 one of the tricuspid valves2 ,pc1 the pericardium2 ,i4sv1 superior intercostal vein2 ,az1 vena azygos2 ,p4,a41 right pulmonary artery2 ,br1 right bronchus2 ,l1 inner lobe of the right lung2 1 sophagus2 ,ao1 descending aorta2 ,h1 liver1 in section1 with hepatic vein1 vena port1 and gall-bladder1 gb1 separated by the diaphragm1 also seen in section1 from the thoracic cavity4 ,but when1 from the four cavities of the heart recognised by us moderns1 one is excluded1 there remain three--which is just what ,aristotle says4 ,the solution of the difficulty is1 in fact1 as absurdly simple as that presented by the egg of ,columbus2 and any error there may be1 is not to be put down to ,aristotle1 but to that inability to comprehend that the same fact may be accurately described in different ways1 which is the special characteristic of the commentatorial mind4 ,that the three cavities mentioned by ,aristotle are just those which remain if the right auricle is omitted1 is plain enough from what is said in 7,b71 7,c71 7,e71 7,i71 and 7,l74 ,for1 in a suffocated animal1 the 8right cavity0 which is directly connected with the great vein1 and is obviously the right ventricle1 being distended with blood1 will look much larger than the middle cavity1 which1 since it gives rise to the aorta1 can only be the left ventricle4 ,and this1 again1 will appear larger than the thin and collapsed left auricle1 which must be ,aristotle's left cavity1 inasmuch as this cavity is said to be connected by with the lung4 ,the reason why ,aristotle considered the left auricle to be a part of the heart1 while he merged the right auricle in the great vein1 is1 obviously1 the small relative size of the venous trunks and their sharper demarcation from the auricle4 ,galen1 however1 perhaps more consistently1 regarded the left auricle also as a mere part of the 8arteria venosa40 ,the canal which leads from the right cavity of the heart to the lung 7or1 as ,aristotle puts it 7,e71 from the lung to the heart7 is1 without doubt1 the pulmonary artery4 ,but it may be said that1 in this case1 ,aristotle contradicts himself1 inasmuch as in 7,p7 and 7,q7 a vessel1 which is obviously the pulmonary artery1 is described as a branch of the great vein4 ,however1 this difficulty also disappears1 if we reflect that1 in ,aristotle's way of looking at the matter1 the line of demarcation between the great vein and the heart coincides with the right auriculo-ventricular aperture2 and that1 inasmuch as the conical prolongation of the right ventricle which leads to the pulmonary artery 7,r4v in the ,figure71 lies close in front of the auricle1 its base may very easily 7as the figure shows7 be regarded as part of the general opening of the great vein into the right ventricle4 ,in fact1 it is clear that ,aristotle1 having failed to notice the valves of the heart1 did not distinguish the part of the right ventricle from which the pulmonary artery arises 7,r4v7 from the proper trunk of the artery on the one hand1 and from the right auricle 7,r4a7 on the other4 ,thus the root1 as we may call it1 of the pulmonary artery and the right auricle1 taken together1 are spoken of as the 8part of the great vein which extends upwards0 7,p72 and1 as the vena azygos 7,az7 was one branch of this1 so the 8vein to the lung0 was regarded as another branch of it4 ,but the latter branch1 being given off close to the connection of the great vein with the ventricle1 was also counted as one of the two by which the 8heart0 7that is to say the right ventricle1 the left ventricle1 and the left auricle of our nomenclature7 communicates with the lung4 ,the only other difficulty that ,i observe is connected with 7,k74 ,if ,aristotle intended by this to affirm that the middle cavity 7the left ventricle71 like the other two1 is directly connected with the lung by a 1 he would be in error4 ,but he has excluded this interpretation of his words by 7,e71 in which the number and relations of the canals1 the existence of which he admits1 are distinctly defined4 ,i can only imagine then1 that1 so far as this passage applies to the left ventricle1 it merely refers to the indirect communication of that cavity with the vessels of the lungs1 through the left auricle4 ,on this evidence ,i submit that there is no escape from the conclusion that1 instead of having committed a gross blunder1 ,aristotle has given a description of the heart which1 so far as it goes1 is remarkably accurate4 ,he is in error only in regard to the differences which he imagines to exist between large and small hearts 7,h74 ,cuvier 7who has been followed by other commentators7 ascribes another error to ,aristotle3-- 8,aristote suppose que la trache-artre se prolonge jusqu'au cur1 et semble croire1 en consquence1 que l'air y pntre 7l4 c4 p4 #aeb740 ,upon what foundation ,cuvier rested the first of these two assertions1 ,i am at a loss to divine4 ,as a matter of fact1 it will appear from the following excerpts that ,aristotle gives an account of the structure of the lungs which is almost as good as that of the heart1 and that it contains nothing about any prolongation of the windpipe to the heart4 8,within the neck lie what is called the sophagus 7so named on account of its length and its narrowness7 and the windpipe 774 ,the position of the windpipe in all animals that have one1 is in front of the sophagus4 ,all animals which possess a lung have a windpipe4 ,the windpipe is of a cartilaginous nature and is exsanguine1 but is surrounded by many little veins4444 8,it goes downwards towards the middle of the lung1 and then divides for each of the halves of the lung4 ,in all animals that possess one1 the lung is divided into two parts2 but1 in those which bring forth their young alive1 the separation is not equally well marked1 least of all in man4 8,in oviparous animals1 such as birds1 and in quadrupeds which are oviparous1 the one half of the lung is widely separated from the other2 so that it appears as if they had two lungs4 ,and from being single1 the windpipe becomes 7divided into7 two1 which extend to each half of the lung4 ,it is fastened to the great vein1 and to what is called the aorta4 ,when the windpipe is blown up1 the air passes into the hollow parts of the lung4 ,in these1 are cartilaginous tubes 77 which unite at an angle2 from the tubes passages 77 traverse the whole of the lung2 they are continually given off1 the smaller from the larger40 7,book i4 #af47 ,that ,aristotle should speak of the lung as a single organ divided into two halves1 and should say that the division is least marked in man1 is puzzling at first2 but the statement becomes intelligible1 if we reflect upon the close union of the bronchi1 the pulmonary vessels and the mediastinal walls of the pleur1 in mammals2#ch and it is quite true that the lungs are much more obviously distinct from one another in birds4 ,aubert and ,wimmer translate the last paragraph of the passage just cited as follows3-- 8,diese haben aber knorpelige ,scheidewnde1 welche unter spitzen ,winkeln zusammentreten1 und aus ihnen fhren ,oeffnungen durch die ganze ,lunge1 indem sie sich in immer kleineren verzweigen40 ,but ,i cannot think that by and 1 in this passage1 ,aristotle meant either 8partitions0 or openings in the ordinary sense of the latter word4 ,for1 in ,book iii4 ,cap4 #c1 in describing the distribution of the 8vein which goes to the lung0 7the pulmonary artery71 he says that it 8extends alongside each tube 77 and each passage 771 the larger beside the larger1 and the smaller beside the smaller2 so that no part 7of the lung7 can be found from which a passage 77 and a vein are absent40 ,moreover1 in ,book i4 #ag1 he says-- 8,canals 77 from the heart pass to the lung and divide in the same fashion as the windpipe does1 closely accompanying those from the windpipe through the whole lung40 ,and again in ,book i4 #ag-- 8,it 7the lung7 is entirely spongy1 and alongside of each tube 77 run canals 77 from the great vein40 ,on comparing the last three statements with the facts of the case1 it is plain that by 1 or tubes1 ,aristotle means the bronchi and so many of their larger divisions as obviously contain cartilages2 and that by he denotes the same things2 and1 if this be so1 then the must be the smaller bronchial canals1 in which the cartilages disappear4 ,this view of the structure of the lung is perfectly correct so far as it extends2 and1 bearing it in mind1 we shall be in a position to understand what ,aristotle thought about the passage of air from the lungs into the heart4 ,in every part of the lung1 he says1 in effect1 there is an air tube which is derived from the trachea1 and other tubes which are derived from the which connect the lung with the heart 7supr1 ,c74 ,their applied walls constitute the thin 8synapses0 7 7 through which the air passes out of the air tubes into the 1 or blood-vessels1 by transudation or diffusion2 for there is no community between the cavities of the air tubes and cavities of the canals2 that is to say1 no opening from one into the other 7supr1 ,d74 ,on the words 8 0 ,aubert and ,wimmer remark 7l4 c4 p4 #bci71 8,da ,a4 die ,ansicht hat die ,lungenluft wrde dem ,herzen zugefhrt1 so postulirt er statt vieler kleiner ,verbindungen einen grossen ,verbindungsgang zwischen ,lunge und ,herz40 ,but does ,aristotle make this assumption8 ,the only evidence so far as ,i know in favour of the affirmative answer to this question is the following passage3-- 8 1 4 1 0 7i4 cap4 #af74 8,the heart and the windpipe are connected by fatty and cartilaginous and fibrous bands2 where they are connected it is hollow4 ,blowing into the windpipe does not show clearly in some animals1 but in the larger animals it is clear that the air goes into it40 ,aubert and ,wimmer give a somewhat different rendering of this passage3-- 8,auch das ,herz hngt mit der ,luftrhre durch fettreiche1 knorpelige und faserige ,bnder zusammen2 und da1 wo sie zusammenhngen1 ist eine ,hhlung4 ,beim ,aufblasen der ,lunge wird es bei manchen ,thieren nicht wahrnehmbar1 bei den grsseren aber ist es offenbar1 dass die ,luft in das ,herz gelangt40 ,the sense here turns upon the signification which is to be ascribed to 4 ,but if these words refer to the heart1 then ,aristotle has distinctly pointed out the road which the air1 in his opinion1 takes1 namely1 through the 8synapses0 7,d72 and there is no reason that ,i can discover to believe that he 8postulated0 any other and more direct communication4 ,with respect to the meaning of 1 ,aubert and ,wimmer observe3-- 8,dies scheint wohl die kurze ,lungenvene zu sein4 ,schneider bezieht dies auf die ,vorkammern1 allein diese werden unten als ,hhlen des ,herzens beschrieben40 ,i am disposed to think1 on the contrary1 that the words refer simply to the cavity of the pericardium4 ,for a part of this cavity 7sinus transversus pericardii7 lies between the aorta1 on the one hand1 and the pulmonary vessels with the bifurcation of the trachea1 on the other hand1 and is much more conspicuous in some animals than in man4 ,it is strictly correct1 therefore1 in ,aristotle's words1 to say that where the heart and the windpipe are connected 8it is hollow40 ,if he had meant to speak of one of the pulmonary veins1 or of any of the cavities of the heart1 he would have used the terms or which he always employs for these parts4 ,according to ,aristotle1 then1 the air taken into the lungs passes1 from the final ramifications of the bronchial tubes into the corresponding branches of the pulmonary blood-vessels1 not through openings1 but by transudation1 or1 as we should nowadays say1 diffusion1 through the thin partitions formed by the applied coats of the two sets of canals4 ,but the 8pneuma0 which thus reached the interior of the blood-vessels was not1 in ,aristotle's opinion1 exactly the same thing as the air4 ,it was 8 0 78,de ,mundo10 iv4 #i7--subtilised and condensed air2 and it is hard to make out whether ,aristotle considered it to possess the physical properties of an elastic fluid or those of a liquid4 ,as he affirms that all the cavities of the heart contain blood 7,f71 it is clear that he did not hold the erroneous view propounded in the next generation by ,erasistratus4 ,on the other hand1 the fact that he supposes that the spermatic arteries do not contain blood but only an 78,hist4 ,animalium10 iii4 #a71 shows that his notions respecting the contents of the arteries were vague4 ,nor does he seem to have known that the pulse is characteristic only of the arteries2 and as he thought that the arteries end in solid fibrous bands1 he naturally could not have entertained the faintest conception of the true motion of the blood4 ,but1 without attempting to read into ,aristotle modern conceptions which never entered his mind1 it is only just to observe that his view of what becomes of the air taken into the lungs is by no means worthy of contempt as a gross error4 ,on the contrary1 here1 as in the case of his anatomy of the heart1 what ,aristotle asserts is true as far as it goes4 ,something does actually pass from the air contained in the lungs through the coats of the vessels into the blood1 and thence to the heart2 to wit1 oxygen4 ,and ,i think that it speaks very well for ancient ,greek science that the investigator of so difficult a physiological problem as that of respiration1 should have arrived at a conclusion1 the statement of which1 after the lapse of more than two thousand years1 can be accepted as a thoroughly established scientific truth4 ,i trust that the case in favour of removing the statements about the heart1 from the list of the 8errors of ,aristotle0 is now clear2 and that the evidence proves1 on the contrary1 that they justify us in forming a very favourable estimate of the oldest anatomical investigations among the ,greeks of which any sufficient record remains4 ,but is ,aristotle to be credited with the merit of having ascertained so much of the truth8 ,this question will not appear superfluous to those who are acquainted with the extraordinary history of ,aristotle's works1 or who adopt the conclusion of ,aubert and ,wimmer1 that1 of the ten books of the 8,historia ,animalium0 which have come down to us1 three are largely or entirely spurious1 and that the others contain many interpolations by later writers4 ,it so happens1 however1 that1 apart from other reasons1 there are satisfactory internal grounds for ascribing the account of the heart to a writer of the time at which ,aristotle lived4 ,for1 within thirty years of his death1 the anatomists of the ,alexandrian school had thoroughly investigated the structure and the functions of the valves of the heart4 ,during this time1 the manuscripts of ,aristotle were in the possession of ,theophrastus2 and no interpolator of later date would have shown that he was ignorant of the nature and significance of these important structures1 by the brief and obscure allusion--8in its cavities there are tendons0 7,a74 ,on the other hand1 ,polybus1 whose account of the vascular system is quoted in the 8,historia ,animalium0 was an elder contemporary of ,aristotle4 ,hence1 if any part of the work faithfully represents that which ,aristotle taught1 we may safely conclude that the description of the heart does so4 ,having granted this much1 however1 it is another question1 whether ,aristotle is to be regarded as the first discoverer of the facts which he has so well stated1 or whether he1 like other men1 was the intellectual child of his time and simply carried on a step or two the work which had been commenced by others4 ,on the subject of ,aristotle's significance as an original worker in biology extraordinarily divergent views have been put forward4 ,if we are to adopt ,cuvier's estimate1 ,aristotle was simply a miracle3-- 8,avant ,aristote la philosophie1 entirement spculative1 se perdait dans les abstractions dpourvues de fondement2 la science n'existait pas4 ,il semble qu'elle soit sortie toute faite du cerveau d',aristote comme ,minerve1 toute arme1 du cerveau de ,jupiter4 ,seul1 en effet1 sans antcdents1 sans rien emprunter aux sicles qui l'avaient prcd1 puisqu'ils n'avaient rien produit de solide1 le disciple de ,platon dcouvrit et dmontra plus de vrits1 executa plus de travaux scientifiques en un vie de soixante-deux ans1 qu'aprs lui vingt sicles n'en ont pu faire10#ci etc4 etc4 8,aristote est le premier qui ait introduit la mthode de l'induction1 de la comparaison des observations pour en faire sortir des ides gnrales1 et celle de l'exprience pour multiplier les faits dont ces ides gnrales peuvent tre dduites40--ii4 p4 #eae4 ,the late ,mr4 ,g4 ,h4 ,lewes1#dj on the contrary1 tells us 8on a superficial examination1 therefore1 he ,aristotle will seem to have given tolerable descriptions2 especially if approached with that disposition to discover marvels which unconsciously determines us in our study of eminent writers4 ,but a more unbiassed and impartial criticism will disclose that he has given no single anatomical description of the least value4 ,all that he knew may have been known1 and probably was known1 without dissection4444 ,i do not assert that he never opened an animal2 on the contrary it seems highly probable that he had opened many4444 ,he never followed the course of a vessel or a nerve2 never laid bare the origin and insertion of a muscle2 never discriminated the component parts of organs2 never made clear to himself the connection of organs into systems40--7pp4 #aef-g47 ,in the face of the description of the heart and lungs1 just quoted1 ,i think we may venture to say that no one who has acquired even an elementary practical acquaintance with anatomy1 and knows of his own knowledge that which ,aristotle describes1 will agree with the opinion expressed by ,mr4 ,lewes2 and those who turn to the accounts of the structure of the rock lobster and the common lobster1 or to that of the ,cephalopods and other ,mollusks1 in the fourth book of the 8,historia ,animalium0 will probably feel inclined to object to it still more strongly4 ,on the other hand1 ,cuvier's exaggerated panegyric will as little bear the test of cool discussion4 ,in ,greece1 the century before ,aristotle's birth was a period of great intellectual activity1 in the field of physical science no less than elsewhere4 ,the method of induction has never been used to better effect than by ,hippocrates2 and the labours of such men as ,alkmeon1 ,demokritus1 and ,polybus1 among ,aristotle's predecessors2 ,diokles1 and ,praxagoras1 among his contemporaries1 laid a solid foundation for the scientific study of anatomy and development1 independently of his labours4 ,aristotle himself informs us that the dissection of animals was commonly practised2 that the aorta had been distinguished from the great vein2 and that the connection of both with the heart had been observed by his predecessors4 ,what they thought about the structure of the heart itself or that of the lungs1 he does not tell us1 and we have no means of knowing4 ,so far from arrogantly suggesting that he owed nothing to his predecessors1 ,aristotle is careful to refer to their observations1 and to explain why1 in his judgment1 they fell into the errors which he corrects4 ,aristotle's knowledge1 in fact1 appears to have stood in the same relation to that of such men as ,polybus and ,diogenes of ,apollonia1 as that of ,herophilus and ,erasistratus did to his own1 so far as the heart is concerned4 ,he carried science a step beyond the point at which he found it2 a meritorious1 but not a miraculous1 achievement4 ,what he did1 required the possession of very good powers of observation2 if they had been powers of the highest class1 he could hardly have left such conspicuous objects as the valves of the heart to be discovered by his successors4 ,and this leads me to make a final remark upon a singular feature of the 8,historia ,animalium40 ,as a whole1 it is a most notable production1 full of accurate information1 and of extremely acute generalisations of the observations accumulated by naturalists up to that time4 ,and yet1 every here and there1 one stumbles upon assertions respecting matters which lie within the scope of the commonest inspection1 which are not so much to be called errors1 as stupidities4 ,what is to be made of the statement that the sutures of women's skulls are different from those of men2 that men and sundry male animals have more teeth than their respective females2 that the back of the skull is empty2 and so on8 ,it is simply incredible to me1 that the ,aristotle who wrote the account of the heart1 also committed himself to absurdities which can be excused by no theoretical prepossession and which are contradicted by the plainest observation4 ,what1 after all1 were the original manuscripts of the 8,historia ,animalium08 ,if they were notes of ,aristotle's lectures taken by some of his students1 any lecturer who has chanced to look through such notes1 would find the interspersion of a foundation of general and sometimes minute accuracy1 with patches of transcendent blundering1 perfectly intelligible4 ,some competent ,greek scholar may perhaps think it worth while to tell us what may be said for or against the hypothesis thus hinted4 ,one obvious difficulty in the way of adopting it is the fact that1 in other works1 ,aristotle refers to the 8,historia ,animalium0 as if it had already been made public by himself4 ,,ix4 ,,on ,,the ,,hypothesis ,,that ,,animals ,,are ,,automata1 ,,and ,,its ,,history4 ,the first half of the seventeenth century is one of the great epochs of biological science4 ,for though suggestions and indications of the conceptions which took definite shape1 at that time1 are to be met with in works of earlier date1 they are little more than the shadows which coming truth casts forward2 men's knowledge was neither extensive enough1 nor exact enough1 to show them the solid body of fact which threw these shadows4 ,but1 in the seventeenth century1 the idea that the physical processes of life are capable of being explained in the same way as other physical phenomena1 and1 therefore1 that the living body is a mechanism1 was proved to be true for certain classes of vital actions2 and1 having thus taken firm root in irrefragable fact1 this conception has not only successfully repelled every assault which has been made upon it1 but has steadily grown in force and extent of application1 until it is now the expressed or implied fundamental proposition of the whole doctrine of scientific ,physiology4 ,if we ask to whom mankind are indebted for this great service1 the general voice will name ,william ,harvey4 ,for1 by his discovery of the circulation of the blood in the higher animals1 by his explanation of the nature of the mechanism by which that circulation is effected1 and by his no less remarkable1 though less known1 investigations of the process of development1 ,harvey solidly laid the foundations of all those physical explanations of the functions of sustentation and reproduction which modern physiologists have achieved4 ,but the living body is not only sustained and reproduced3 it adjusts itself to external and internal changes2 it moves and feels4 ,the attempt to reduce the endless complexities of animal motion and feeling to law and order is1 at least1 as important a part of the task of the physiologist as the elucidation of what are sometimes called the vegetative processes4 ,harvey did not make this attempt himself2 but the influence of his work upon the man who did make it is patent and unquestionable4 ,this man was ,ren ,descartes1 who1 though by many years ,harvey's junior1 died before him2 and yet1 in his short span of fifty-four years1 took an undisputed place1 not only among the chiefs of philosophy1 but amongst the greatest and most original of mathematicians2 while1 in my belief1 he is no less certainly entitled to the rank of a great and original physiologist2 inasmuch as he did for the physiology of motion and sensation that which ,harvey had done for the circulation of the blood1 and opened up that road to the mechanical theory of these processes1 which has been followed by all his successors4 ,descartes was no mere speculator1 as some would have us believe3 but a man who knew of his own knowledge what was to be known of the facts of anatomy and physiology in his day4 ,he was an unwearied dissector and observer2 and it is said1 that1 on a visitor once asking to see his library1 ,descartes led him into a room set aside for dissections1 and full of specimens under examination4 8,there10 said he1 8is my library40 ,i anticipate a smile of incredulity when ,i thus champion ,descartes' claim to be considered a physiologist of the first rank4 ,i expect to be told that ,i have read into his works what ,i find there1 and to be asked1 ,why is it that we are left to discover ,descartes' deserts at this time of day1 more than two centuries after his death8 ,how is it that ,descartes is utterly ignored in some of the latest works which treat expressly of the subject in which he is said to have been so great8 ,it is much easier to ask such questions than to answer them1 especially if one desires to be on good terms with one's contemporaries2 but1 if ,i must give an answer1 it is this3 ,the growth of physical science is now so prodigiously rapid1 that those who are actively engaged in keeping up with the present1 have much ado to find time to look at the past1 and even grow into the habit of neglecting it4 ,but1 natural as this result may be1 it is none the less detrimental4 ,the intellect loses1 for there is assuredly no more effectual method of clearing up one's own mind on any subject than by talking it over1 so to speak1 with men of real power and grasp1 who have considered it from a totally different point of view4 ,the parallax of time helps us to the true position of a conception1 as the parallax of space helps us to that of a star4 ,and the moral nature loses no less4 ,it is well to turn aside from the fretful stir of the present and to dwell with gratitude and respect upon the services of those 8mighty men of old who have gone down to the grave with their weapons of war10 but who1 while they yet lived1 won splendid victories over ignorance4 ,it is well1 again1 to reflect that the fame of ,descartes filled all ,europe1 and his authority overshadowed it1 for a century2 while now1 most of those who know his name think of him1 either as a person who had some preposterous notions about vortices and was deservedly annihilated by the great ,sir ,isaac ,newton2 or as the apostle of an essentially vicious method of deductive speculation2 and that1 nevertheless1 neither the chatter of shifting opinion1 nor the silence of personal oblivion1 has in the slightest degree affected the growth of the great ideas of which he was the instrument and the mouthpiece4 ,it is a matter of fact that the greatest physiologist of the eighteenth century1 ,haller1 in treating of the functions of nerve1 does little more than reproduce and enlarge upon the ideas of ,descartes4 ,it is a matter of fact that ,david ,hartley1 in his remarkable work the 8,essay on ,man10 expressly1 though still insufficiently1 acknowledges the resemblance of his fundamental conceptions to those of ,descartes2 and ,i shall now endeavour to show that a series of propositions1 which constitute the foundation and essence of the modern physiology of the nervous system1 are fully expressed and illustrated in the works of ,descartes4 ,i4 ,the brain is the organ of sensation1 thought1 and emotion2 that is to say1 some change in the condition of the matter of this organ is the invariable antecedent of the state of consciousness to which each of these terms is applied4 ,in the 8,principes de la ,philosophie0 7 #afi71 ,descartes says3--#da 8,although the soul is united to the whole body1 its principal functions are1 nevertheless1 performed in the brain2 it is here that it not only understands and imagines1 but also feels2 and this is effected by the intermediation of the nerves1 which extend in the form of delicate threads from the brain to all parts of the body1 to which they are attached in such a manner1 that we can hardly touch any part of the body without setting the extremity of some nerve in motion4 ,this motion passes along the nerve to that part of the brain which is the common sensorium1 as ,i have sufficiently explained in my ,treatise on ,dioptrics2 and the movements which thus travel along the nerves1 as far as that part of the brain with which the soul is closely joined and united1 cause it1 by reason of their diverse characters1 to have different thoughts4 ,and it is these different thoughts of the soul1 which arise immediately from the movements that are excited by the nerves in the brain1 which we properly term our feelings1 or the perceptions of our senses40 ,elsewhere1#db ,descartes1 in arguing that the seat of the passions is not 7as many suppose7 the heart1 but the brain1 uses the following remarkable language3-- 8,the opinion of those who think that the soul receives its passions in the heart1 is of no weight1 for it is based upon the fact that the passions cause a change to be felt in that organ2 and it is easy to see that this change is felt1 as if it were in the heart1 only by the intermediation of a little nerve which descends from the brain to it2 ,just as pain is felt1 as if it were in the foot1 by the intermediation of the nerves of the foot2 and the stars are perceived1 as if they were in the heavens1 by the intermediation of their light and of the optic nerves4 ,so that it is no more necessary for the soul to exert its functions immediately in the heart1 to feel its passions there1 than it is necessary that it should be in the heavens to see the stars there40 ,this definite allocation of all the phenomena of consciousness to the brain as their organ1 was a step the value of which it is difficult for us to appraise1 so completely has ,descartes' view incorporated itself with every-day thought and common language4 ,a lunatic is said to be 8crack-brained0 or 8touched in the head10 a confused thinker is 8muddle-headed10 while a clever man is said to have 8plenty of brains20 but it must be remembered that at the end of the last century a considerable1 though much over-estimated1 anatomist1 ,bichat1 so far from having reached the level of ,descartes1 could gravely argue that the apparatuses of organic life are the sole seat of the passions1 which in no way affect the brain1 except so far as it is the agent by which the influence of the passions is transmitted to the muscles4#dc ,modern physiology1 aided by pathology1 easily demonstrates that the brain is the seat of all forms of consciousness1 and fully bears out ,descartes' explanation of the reference of those sensations in the viscera which accompany intense emotion1 to these organs4 ,it proves1 directly1 that those states of consciousness which we call sensations are the immediate consequent of a change in the brain excited by the sensory nerves2 and1 on the well-known effects of injuries1 of stimulants1 and of narcotics1 it bases the conclusion that thought and emotion are1 in like manner1 the consequents of physical antecedents4 ,,ii4 ,the movements of animals are due to the change of form of muscles1 which shorten and become thicker2 and this change of form in a muscle arises from a motion of the substance contained within the nerves which go to the muscle4 ,in the 8,passions de l'me10 ,art4 vii41 ,descartes writes3-- 8,moreover1 we know that all the movements of the limbs depend on the muscles1 and that these muscles are opposed to one another in such a manner1 that when one of them shortens1 it draws along the part of the body to which it is attached1 and so gives rise to a simultaneous elongation of the muscle which is opposed to it4 ,then1 if it happens1 afterwards1 that the latter shortens1 it causes the former to elongate1 and draws towards itself the part to which it is attached4 ,lastly1 we know that all these movements of the muscles1 as all the senses1 depend on the nerves1 which are like little threads or tubes1 which all come from the brain1 and1 like it1 contain a certain very subtle air or wind1 termed the animal spirits40 ,the property of muscle mentioned by ,descartes now goes by the general name of contractility1 but his definition of it remains untouched4 ,the long-continued controversy whether contractile substance1 speaking generally1 has an inherent power of contraction1 or whether it contracts only in virtue of an influence exerted by nerve1 is now settled in ,haller's favour2 but ,descartes' statement of the dependence of muscular contraction on nerve holds good for the higher forms of muscle1 under normal circumstances2 so that1 although the structure of the various modifications of contractile matter has been worked out with astonishing minuteness--although the delicate physical and chemical changes which accompany muscular contraction have been determined to an extent of which ,descartes could not have dreamed1 and have quite upset his hypothesis that the cause of the shortening and thickening of the muscle is the flow of animal spirits into it from the nerves--the important and fundamental part of his statement remains perfectly true4 ,the like may be affirmed of what he says about nerve4 ,we know now that nerves are not exactly tubes1 and that 8animal spirits0 are myths2 but the exquisitely refined methods of investigation of ,dubois-,reymond and of ,helmholz have no less clearly proved that the antecedent of ordinary muscular contraction is a motion of the molecules of the nerve going to the muscle2 and that this motion is propagated with a measurable1 and by no means great1 velocity1 through the substance of the nerve towards the muscle4 ,with the progress of research1 the term 8animal spirits0 gave way to 8nervous fluid10 and 8nervous fluid0 has now given way to 8molecular motion of nerve-substance40 ,our conceptions of what takes place in nerve have altered in the same way as our conceptions of what takes place in a conducting wire have altered1 since electricity was shown to be not a fluid1 but a mode of molecular motion4 ,the change is of vast importance1 but it does not affect ,descartes' fundamental idea1 that a change in the substance of a motor nerve propagated towards a muscle is the ordinary cause of muscular contraction4 ,,iii4 ,the sensations of animals are due to a motion of the substance of the nerves which connect the sensory organs with the brain4 ,in ,la ,dioptrique 7,discours ,quatrime71 ,descartes explains1 more fully than in the passage cited above1 his hypothesis of the mode of action of sensory nerves3-- 8,it is the little threads of which the inner substance of the nerves is composed which subserve sensation4 ,you must conceive that these little threads1 being inclosed in tubes1 which are always distended and kept open by the animal spirits which they contain1 neither press upon nor interfere with one another1 and are extended from the brain to the extremities of all the members which are sensitive--in such a manner1 that the slightest touch which excites the part of one of the members to which a thread is attached1 gives rise to a motion of the part of the brain whence it arises1 just as by pulling one of the ends of a stretched cord1 the other end is instantaneously moved4444 ,and we must take care not to imagine that1 in order to feel1 the soul needs to behold certain images sent by the objects of sense to the brain1 as our philosophers commonly suppose2 or1 at least1 we must conceive these images to be something quite different from what they suppose them to be4 ,for1 as all they suppose is that these images ought to resemble the objects which they represent1 it is impossible for them to show how they can be formed by the objects received by the organs of the external senses and transmitted to the brain4 ,and they have had no reason for supposing the existence of these images except this2 seeing that the mind is readily excited by a picture to conceive the object which is depicted1 they have thought that it must be excited in the same way to conceive those objects which affect our senses by little pictures of them formed in the head2 instead of which we ought to recollect that there are many things besides images which may excite the mind1 as1 for example1 signs and words1 which have not the least resemblance to the objects which they signify40#dd ,modern physiology amends ,descartes' conception of the mode of action of sensory nerves in detail1 by showing that their structure is the same as that of motor nerves2 and that the changes which take place in them1 when the sensory organs with which they are connected are excited1 are of just the same nature as those which occur in motor nerves1 when the muscles to which they are distributed are made to contract3 there is a molecular change which1 in the case of the sensory nerve1 is propagated towards the brain4 ,but the great fact insisted upon by ,descartes1 that no likeness of external things is1 or can be1 transmitted to the mind by the sensory organs2 on the contrary1 that1 between the external cause of a sensation and the sensation1 there is interposed a mode of motion of nervous matter1 of which the state of consciousness is no likeness1 but a mere symbol1 is of the profoundest importance4 ,it is the physiological foundation of the doctrine of the relativity of knowledge1 and a more or less complete idealism is a necessary consequence of it4 ,for of two alternatives one must be true4 ,either consciousness is the function of a something distinct from the brain1 which we call the soul1 and a sensation is the mode in which this soul is affected by the motion of a part of the brain2 or there is no soul1 and a sensation is something generated by the mode of motion of a part of the brain4 ,in the former case1 the phenomena of the senses are purely spiritual affections2 in the latter1 they are something manufactured by the mechanism of the body1 and as unlike the causes which set that mechanism in motion1 as the sound of a repeater is unlike the pushing of the spring which gives rise to it4 ,the nervous system stands between consciousness and the assumed external world1 as an interpreter who can talk with his fingers stands between a hidden speaker and a man who is stone deaf--and ,realism is equivalent to a belief on the part of the deaf man1 that the speaker must also be talking with his fingers4 8,les extrmes se touchent20 the shibboleth of materialists that 8thought is a secretion of the brain10 is the ,fichtean doctrine that 8the phenomenal universe is the creation of the ,ego10 expressed in other language4 ,,iv4 ,the motion of the matter of a sensory nerve may be transmitted through the brain to motor nerves1 and thereby give rise to contraction of the muscles to which these motor nerves are distributed2 and this reflection of motion from a sensory into a motor nerve may take place without volition1 or even contrary to it4 ,in stating these important truths1 ,descartes defined that which we now term 8reflex action40 ,indeed he almost uses the term itself1 as he talks of the 8animal spirits0 as 8rflchis10#de from the sensory into the motor nerves4 ,and that this use of the word 8reflected0 was no mere accident1 but that the importance and appropriateness of the idea it suggests was fully understood by ,descartes' contemporaries1 is apparent from a passage in ,willis's well-known essay1 8,de ,anim ,brutorum10 published in #afgb1 in which1 in giving an account of ,descartes' views1 he speaks of the animal spirits being diverted into motor channels1 8velut undulatione reflex40#df ,nothing can be clearer in statement1 or in illustration1 than the view of reflex action which ,descartes gives in the 8,passions de l'me10 ,art4 xiii4 ,after recapitulating the manner in which sensory impressions transmitted by the sensory nerves to the brain give rise to sensation1 he proceeds3-- 8,and in addition to the different feelings excited in the soul by these different motions of the brain1 the animal spirits1 without the intervention of the soul1 may take their course towards certain muscles1 rather than towards others1 and thus move the limbs1 as ,i shall prove by an example4 ,if some one moves his hand rapidly towards our eyes1 as if he were going to strike us1 although we know that he is a friend1 that he does it only in jest1 and that he will be very careful to do us no harm1 nevertheless it will be hard to keep from winking4 ,and this shows1 that it is not by the agency of the soul that the eyes shut1 since this action is contrary to that volition which is the only1 or at least the chief1 function of the soul2 but it is because the mechanism of our body is so disposed1 that the motion of the hand towards our eyes excites another movement in our brain1 and this sends the animal spirits into those muscles which cause the eyelids to close40 ,since ,descartes' time1 experiment has eminently enlarged our knowledge of the details of reflex action4 ,the discovery of ,bell has enabled us to follow the tracks of the sensory and motor impulses1 along distinct bundles of nerve fibres2 and the spinal cord1 apart from the brain1 has been proved to be a great centre of reflex action2 but the fundamental conception remains as ,descartes left it1 and it is one of the pillars of nerve physiology at the present day4 ,v4 ,the motion of any given portion of the matter of the brain excited by the motion of a sensory nerve1 leaves behind a readiness to be moved in the same way1 in that part4 ,anything which resuscitates the motion gives rise to the appropriate feeling4 ,this is the physical mechanism of memory4 ,descartes imagined that the pineal body 7a curious appendage to the upper side of the brain1 the function of which1 if it have any1 is wholly unknown7 was the instrument through which the soul received impressions from1 and communicated them to1 the brain4 ,and he thus endeavours to explain what happens when one tries to recollect something3-- 8,thus when the soul wills to remember anything1 this volition1 causing the pineal gland to incline itself in different directions1 drives the animal spirits towards different regions of the brain1 until they reach that part in which are the traces1 which the object which it desires to remember has left4 ,these traces are produced thus3 those pores of the brain through which the animal spirits have previously been driven1 by reason of the presence of the object1 have thereby acquired a tendency to be opened by the animal spirits which return towards them1 more easily than other pores1 so that the animal spirits1 impinging on these pores1 enter them more readily than others4 ,by this means they excite a particular movement in the pineal gland1 which represents the object to the soul1 and causes it to know what it is which it desired to recollect40#dg ,that memory is dependent upon some condition of the brain is a fact established by many considerations--among the most important of which are the remarkable phenomena of aphasia4 ,and that the condition of the brain on which memory depends1 is largely determined by the repeated occurrence of that condition of its molecules1 which gives rise to the idea of the thing remembered1 is no less certain4 ,every boy who learns his lesson by repeating it exemplifies the fact4 ,descartes1 as we have seen1 supposes that the pores of a given part of the brain are stretched by the animal spirits1 on the occurrence of a sensation1 and that the part of the brain thus stretched1 being imperfectly elastic1 does not return to exactly its previous condition1 but remains more distensible than it was before4 ,hartley supposes that the vibrations1 excited by a sensory1 or other1 impression1 do not die away1 but are represented by smaller vibrations or 8vibratiuncules10 the permanency and intensity of which are in relation with the frequency of repetition of the primary vibrations4 ,haller has substantially the same idea1 but contents himself with the general term 8mutationes10 to express the cerebral change which is the cause of a state of consciousness4 ,these 8mutationes0 persist for a long time after the cause which gives rise to them has ceased to operate1 and are arranged in the brain according to the order of coexistence and succession of their causes4 ,and he gives these persistent 8mutationes0 the picturesque name of vestigia rerum1 8qu non in mente sed in ipso corpore et in medulla quidem cerebri ineffabili modo incredibiliter minutis notis et copia infinita1 inscript sunt40#dh ,i do not know that any modern theory of the physical conditions of memory differs essentially from these1 which are all children--mutatis mutandis--of the ,cartesian doctrine4 ,physiology is1 at present1 incompetent to say anything positively about the matter1 or to go farther than the expression of the high probability1 that every molecular change which gives rise to a state of consciousness1 leaves a more or less persistent structural modification1 through which the same molecular change may be regenerated by other agencies than the cause which first produced it4 ,thus far1 the propositions respecting the physiology of the nervous system which are stated by ,descartes have simply been more clearly defined1 more fully illustrated1 and1 for the most part1 demonstrated1 by modern physiological research4 ,but there remains a doctrine to which ,descartes attached great weight1 so that full acceptance of it became a sort of note of a thorough-going ,cartesian1 but which1 nevertheless1 is so opposed to ordinary prepossessions that it attained more general notoriety1 and gave rise to more discussion1 than almost any other ,cartesian hypothesis4 ,it is the doctrine1 that brute animals are mere machines or automata1 devoid not only of reason1 but of any kind of consciousness1 which is stated briefly in the 8,discours de la ,mthode10 and more fully in the 8,rponses aux ,quatrimes ,objections10 and in the correspondence with ,henry ,more4#di ,the process of reasoning by which ,descartes arrived at this startling conclusion is well shown in the following passage of the 8,rponses30-- 8,but as regards the souls of beasts1 although this is not the place for considering them1 and though1 without a general exposition of physics1 ,i can say no more on this subject than ,i have already said in the fifth part of my ,treatise on ,method2 yet1 ,i will further state1 here1 that it appears to me to be a very remarkable circumstance that no movement can take place1 either in the bodies of beasts1 or even in our own1 if these bodies have not in themselves all the organs and instruments by means of which the very same movements would be accomplished in a machine4 ,so that1 even in us1 the spirit1 or the soul1 does not directly move the limbs1 but only determines the course of that very subtle liquid which is called the animal spirits1 which1 running continually from the heart by the brain into the muscles1 is the cause of all the movements of our limbs1 and often may cause many different motions1 one as easily as the other4 8,and it does not even always exert this determination2 for among the movements which take place in us1 there are many which do not depend on the mind at all1 such as the beating of the heart1 the digestion of food1 the nutrition1 the respiration1 of those who sleep2 and1 even in those who are awake1 walking1 singing1 and other similar actions1 when they are performed without the mind thinking about them4 ,and1 when one who falls from a height throws his hands forwards to save his head1 it is in virtue of no ratiocination that he performs this action2 it does not depend upon his mind1 but takes place merely because his senses being affected by the present danger1 some change arises in his brain which determines the animal spirits to pass thence into the nerves1 in such a manner as is required to produce this motion1 in the same way as in a machine1 and without the mind being able to hinder it4 ,now since we observe this in ourselves1 why should we be so much astonished if the light reflected from the body of a wolf into the eye of a sheep has the same force to excite in it the motion of flight8 8,after having observed this1 if we wish to learn by reasoning1 whether certain movements of beasts are comparable to those which are effected in us by the operation of the mind1 or1 on the contrary1 to those which depend only on the animal spirits and the disposition of the organs1 it is necessary to consider the difference between the two1 which ,i have explained in the fifth part of the ,discourse on ,method 7for ,i do not think that any others are discoverable71 and then it will easily be seen1 that all the actions of beasts are similar only to those which we perform without the help of our minds4 ,for which reason we shall be forced to conclude1 that we know of the existence in them of no other principle of motion than the disposition of their organs and the continual affluence of animal spirits produced by the heat of the heart1 which attenuates and subtilises the blood2 and1 at the same time1 we shall acknowledge that we have had no reason for assuming any other principle1 except that1 not having distinguished these two principles of motion1 and seeing that the one1 which depends only on the animal spirits and the organs1 exists in beasts as well as in us1 we have hastily concluded that the other1 which depends on mind and on thought1 was also possessed by them40 ,descartes' line of argument is perfectly clear4 ,he starts from reflex action in man1 from the unquestionable fact that1 in ourselves1 co-ordinate1 purposive1 actions may take place1 without the intervention of consciousness or volition1 or even contrary to the latter4 ,as actions of a certain degree of complexity are brought about by mere mechanism1 why may not actions of still greater complexity be the result of a more refined mechanism8 ,what proof is there that brutes are other than a superior race of marionettes1 which eat without pleasure1 cry without pain1 desire nothing1 know nothing1 and only simulate intelligence as a bee simulates a mathematician8#ej ,the ,port ,royalists adopted the hypothesis that brutes are machines1 and are said to have carried its practical applications so far1 as to treat domestic animals with neglect1 if not with actual cruelty4 ,as late as the middle of the eighteenth century1 the problem was discussed very fully and ably by ,bouillier1 in his 8,essai philosophique sur l'me des ,btes10 while ,condillac deals with it in his 8,trait des ,animaux20 but since then it has received little attention4 ,nevertheless1 modern research has brought to light a great multitude of facts1 which not only show that ,descartes' view is defensible1 but render it far more defensible than it was in his day4 ,it must be premised1 that it is wholly impossible absolutely to prove the presence or absence of consciousness in anything but one's own brain1 though1 by analogy1 we are justified in assuming its existence in other men4 ,now if1 by some accident1 a man's spinal cord is divided1 his limbs are paralysed1 so far as his volition is concerned1 below the point of injury2 and he is incapable of experiencing all those states of consciousness1 which1 in his uninjured state1 would be excited by irritation of those nerves which come off below the injury4 ,if the spinal cord is divided in the middle of the back1 for example1 the skin of the feet may be cut1 or pinched1 or burned1 or wetted with vitriol1 without any sensation of touch1 or of pain1 arising in consciousness4 ,so far as the man is concerned1 therefore1 the part of the central nervous system which lies beyond the injury is cut off from consciousness4 ,it must indeed be admitted1 that1 if any one think fit to maintain that the spinal cord below the injury is conscious1 but that it is cut off from any means of making its consciousness known to the other consciousness in the brain1 there is no means of driving him from his position by logic4 ,but assuredly there is no way of proving it1 and in the matter of consciousness1 if in anything1 we may hold by the rule1 8,de non apparentibus et de non existentibus eadem est ratio40 ,however near the brain the spinal cord is injured1 consciousness remains intact1 except that the irritation of parts below the injury is no longer represented by sensation4 ,on the other hand1 pressure upon the anterior division of the brain1 or extensive injuries to it1 abolish consciousness4 ,hence1 it is a highly probable conclusion1 that consciousness in man depends upon the integrity of the anterior division of the brain1 while the middle and hinder divisions of the brain1 and the rest of the nervous centres1 have nothing to do with it4 ,and it is further highly probable1 that what is true for man is true for other vertebrated animals4 ,we may assume1 then1 that in a living vertebrated animal1 any segment of the cerebro-spinal axis 7or spinal cord and brain7 separated from that anterior division of the brain which is the organ of consciousness1 is as completely incapable of giving rise to consciousness1 as we know it to be incapable of carrying out volitions4 ,nevertheless1 this separated segment of the spinal cord is not passive and inert4 ,on the contrary1 it is the seat of extremely remarkable powers4 ,in our imaginary case of injury1 the man would1 as we have seen1 be devoid of sensation in his legs1 and would have not the least power of moving them4 ,but1 if the soles of his feet were tickled1 the legs would be drawn up1 just as vigorously as they would have been before the injury4 ,we know exactly what happens when the soles of the feet are tickled2 a molecular change takes place in the sensory nerves of the skin1 and is propagated along them and through the posterior roots of the spinal nerves1 which are constituted by them1 to the grey matter of the spinal cord4 ,through that grey matter1 the molecular motion is reflected into the anterior roots of the same nerves1 constituted by the filaments which supply the muscles of the legs1 and1 travelling along these motor filaments1 reaches the muscles1 which at once contract1 and cause the limbs to be drawn up4 ,in order to move the legs in this way1 a definite co-ordination of muscular contractions is necessary2 the muscles must contract in a certain order and with duly proportioned force2 and moreover1 as the feet are drawn away from the source of irritation1 it may be said that the action has a final cause1 or is purposive4 ,thus it follows1 that the grey matter of the segment of the man's spinal cord1 though it is devoid of consciousness1 nevertheless responds to a simple stimulus by giving rise to a complex set of muscular contractions1 co-ordinated towards a definite end1 and serving an obvious purpose4 ,if the spinal cord of a frog is cut across1 so as to provide us with a segment separated from the brain1 we shall have a subject parallel to the injured man1 on which experiments can be made without remorse2 as we have a right to conclude that a frog's spinal cord is not likely to be conscious1 when a man's is not4 ,now the frog behaves just as the man did4 ,the legs are utterly paralysed1 so far as voluntary movement is concerned2 but they are vigorously drawn up to the body when any irritant is applied to the foot4 ,but let us study our frog a little farther4 ,touch the skin of the side of the body with a little acetic acid1 which gives rise to all the signs of great pain in an uninjured frog4 ,in this case1 there can be no pain1 because the application is made to a part of the skin supplied with nerves which come off from the cord below the point of section2 nevertheless1 the frog lifts up the limb of the same side1 and applies the foot to rub off the acetic acid2 and1 what is still more remarkable1 if the limb be held so that the frog cannot use it1 it will1 by-and-by1 move the limb of the other side1 turn it across the body1 and use it for the same rubbing process4 ,it is impossible that the frog1 if it were in its entirety and could reason1 should perform actions more purposive than these3 and yet we have most complete assurance that1 in this case1 the frog is not acting from purpose1 has no consciousness1 and is a mere insensible machine4 ,but now suppose that1 instead of making a section of the cord in the middle of the body1 it had been made in such a manner as to separate the hindermost division of the brain from the rest of the organ1 and suppose the foremost two-thirds of the brain entirely taken away4 ,the frog is then absolutely devoid of any spontaneity2 it sits upright in the attitude which a frog habitually assumes2 and it will not stir unless it is touched2 but it differs from the frog which ,i have just described in this1 that1 if it be thrown into the water1 it begins to swim1 and swims just as well as the perfect frog does4 ,but swimming requires the combination and successive co-ordination of a great number of muscular actions4 ,and we are forced to conclude1 that the impression made upon the sensory nerves of the skin of the frog by the contact with the water into which it is thrown1 causes the transmission to the central nervous apparatus of an impulse1 which sets going a certain machinery by which all the muscles of swimming are brought into play in due co-ordination4 ,if the frog be stimulated by some irritating body1 it jumps or walks as well as the complete frog can do4 ,the simple sensory impression1 acting through the machinery of the cord1 gives rise to these complex combined movements4 ,it is possible to go a step farther4 ,suppose that only the anterior division of the brain--so much of it as lies in front of the 8optic lobes0--is removed4 ,if that operation is performed quickly and skilfully1 the frog may be kept in a state of full bodily vigour for months1 or it may be for years2 but it will sit unmoved4 ,it sees nothing2 it hears nothing4 ,it will starve sooner than feed itself1 although food put into its mouth is swallowed4 ,on irritation1 it jumps or walks2 if thrown into the water it swims4 ,if it be put on the hand1 it sits there1 crouched1 perfectly quiet1 and would sit there for ever4 ,if the hand be inclined very gently and slowly1 so that the frog would naturally tend to slip off1 the creature's fore paws are shifted on to the edge of the hand1 until he can just prevent himself from falling4 ,if the turning of the hand be slowly continued1 he mounts up with great care and deliberation1 putting first one leg forward and then another1 until he balances himself with perfect precision upon the edge2 and1 if the turning of the hand is continued1 over he goes through the needful set of muscular operations1 until he comes to be seated in security1 upon the back of the hand4 ,the doing of all this requires a delicacy of co-ordination1 and a precision of adjustment of the muscular apparatus of the body1 which are only comparable to those of a rope-dancer4 ,to the ordinary influences of light1 the frog1 deprived of its cerebral hemispheres1 appears to be blind4 ,nevertheless1 if the animal be put upon a table1 with a book at some little distance between it and the light1 and the skin of the hinder part of its body is then irritated1 it will jump forward1 avoiding the book by passing to the right or left of it4 ,therefore1 although the frog appears to have no sensation of light1 visible objects act through its brain upon the motor mechanism of its body4#ea ,it is obvious1 that had ,descartes been acquainted with these remarkable results of modern research1 they would have furnished him with far more powerful arguments than he possessed in favour of his view of the automatism of brutes4 ,the habits of a frog1 leading its natural life1 involve such simple adaptations to surrounding conditions1 that the machinery which is competent to do so much without the intervention of consciousness1 might well do all4 ,and this argument is vastly strengthened by what has been learned in recent times of the marvellously complex operations which are performed mechanically1 and to all appearance without consciousness1 by men1 when1 in consequence of injury or disease1 they are reduced to a condition more or less comparable to that of a frog1 in which the anterior part of the brain has been removed4 ,a case has recently been published by an eminent ,french physician1 ,dr4 ,mesnet1 which illustrates this condition so remarkably1 that ,i make no apology for dwelling upon it at considerable length4#eb ,a sergeant of the ,french army1 ,f----1 twenty-seven years of age1 was wounded during the battle of ,bazeilles1 by a ball which fractured his left parietal bone4 ,he ran his bayonet through the ,prussian soldier who wounded him1 but almost immediately his right arm became paralysed2 after walking about two hundred yards1 his right leg became similarly affected1 and he lost his senses4 ,when he recovered them1 three weeks afterwards1 in hospital at ,mayence1 the right half of the body was completely paralysed1 and remained in this condition for a year4 ,at present1 the only trace of the paralysis which remains is a slight weakness of the right half of the body4 ,three or four months after the wound was inflicted1 periodical disturbances of the functions of the brain made their appearance1 and have continued ever since4 ,the disturbances last from fifteen to thirty hours2 the intervals at which they occur being from fifteen to thirty days4 ,for four years1 therefore1 the life of this man has been divided into alternating phases--short abnormal states intervening between long normal states4 ,in the periods of normal life1 the ex-sergeant's health is perfect2 he is intelligent and kindly1 and performs1 satisfactorily1 the duties of a hospital attendant4 ,the commencement of the abnormal state is ushered in by uneasiness and a sense of weight about the forehead1 which the patient compares to the constriction of a circle of iron2 and1 after its termination1 he complains1 for some hours1 of dulness and heaviness of the head4 ,but the transition from the normal to the abnormal state takes place in a few minutes1 without convulsions or cries1 and without anything to indicate the change to a bystander4 ,his movements remain free and his expression calm1 except for a contraction of the brow1 an incessant movement of the eyeballs1 and a chewing motion of the jaws4 ,the eyes are wide open1 and their pupils dilated4 ,if the man happens to be in a place to which he is accustomed1 he walks about as usual2 but1 if he is in a new place1 or if obstacles are intentionally placed in his way1 he stumbles gently against them1 stops1 and then1 feeling over the objects with his hands1 passes on one side of them4 ,he offers no resistance to any change of direction which may be impressed upon him1 or to the forcible acceleration or retardation of his movements4 ,he eats1 drinks1 smokes1 walks about1 dresses and undresses himself1 rises and goes to bed at the accustomed hours4 ,nevertheless1 pins may be run into his body1 or strong electric shocks sent through it1 without causing the least indication of pain2 no odorous substance1 pleasant or unpleasant1 makes the least impression2 he eats and drinks with avidity whatever is offered1 and takes asaftida1 or vinegar1 or quinine1 as readily as water2 no noise affects him2 and light influences him only under certain conditions4 ,dr4 ,mesnet remarks1 that the sense of touch alone seems to persist1 and indeed to be more acute and delicate than in the normal state2 and it is by means of the nerves of touch1 almost exclusively1 that his organism is brought into relation with the external world4 ,here a difficulty arises4 ,it is clear from the facts detailed1 that the nervous apparatus by which1 in the normal state1 sensations of touch are excited1 is that by which external influences determine the movements of the body1 in the abnormal state4 ,but does the state of consciousness1 which we term a tactile sensation1 accompany the operation of this nervous apparatus in the abnormal state8 or is consciousness utterly absent1 the man being reduced to an insensible mechanism8 ,it is impossible to obtain direct evidence in favour of the one conclusion or the other2 all that can be said is1 that the case of the frog shows that the man may be devoid of any kind of consciousness4 ,a further difficult problem is this4 ,the man is insensible to sensory impressions made through the ear1 the nose1 the tongue1 and1 to a great extent1 the eye2 nor is he susceptible of pain from causes operating during his abnormal state4 ,nevertheless1 it is possible so to act upon his tactile apparatus1 as to give rise to those molecular changes in his sensorium1 which are ordinarily the causes of associated trains of ideas4 ,i give a striking example of this process in ,dr4 ,mesnet's words3-- 8,il se promenait dans le jardin1 sous un massif d'arbres1 on lui remet la main sa canne qu'il avait laiss tomber quelques minutes avant4 ,il la palpe1 promne plusieurs reprises la main sur la poigne coude de sa canne--devient attentif--semble prter l'oreille--et1 tout--coup1 appelle #8,henri6' ,puis1 #8,les voil6 ,ils sont au moins une vingtaine6 nous deux1 nous en viendrons bout6' ,et alors portant la main derrire son dos comme pour prendre une cartouche1 il fait le mouvement de charger son arme1 se couche dans l'herbe plat ventre1 la tte cache par un arbre1 dans la position d'un tirailleur1 et suit1 l'arme paule1 tous les mouvements de l'ennemi qu'il croit voir courte distance40 ,in a subsequent abnormal period1 ,dr4 ,mesnet caused the patient to repeat this scene by placing him in the same conditions4 ,now1 in this case1 the question arises whether the series of actions constituting this singular pantomime was accompanied by the ordinary states of consciousness1 the appropriate train of ideas1 or not8 ,did the man dream that he was skirmishing8 or was he in the condition of one of ,vaucauson's automata--a senseless mechanism worked by molecular changes in his nervous system8 ,the analogy of the frog shows that the latter assumption is perfectly justifiable4 ,the ex-sergeant has a good voice1 and had1 at one time1 been employed as a singer at a caf4 ,in one of his abnormal states he was observed to begin humming a tune4 ,he then went to his room1 dressed himself carefully1 and took up some parts of a periodical novel1 which lay on his bed1 as if he were trying to find something4 ,dr4 ,mesnet1 suspecting that he was seeking his music1 made up one of these into a roll and put it into his hand4 ,he appeared satisfied1 took up his cane and went down-stairs to the door4 ,here ,dr4 ,mesnet turned him round1 and he walked quite contentedly1 in the opposite direction1 towards the room of the concirge4 ,the light of the sun shining through a window now happened to fall upon him1 and seemed to suggest the footlights of the stage on which he was accustomed to make his appearance4 ,he stopped1 opened his roll of imaginary music1 put himself into the attitude of a singer1 and sang1 with perfect execution1 three songs1 one after the other4 ,after which he wiped his face with his handkerchief and drank1 without a grimace1 a tumbler of strong vinegar and water which was put into his hand4 ,an experiment which may be performed upon the frog deprived of the fore part of its brain1 well known as ,gltz's 8,quak-versuch10 affords a parallel to this performance4 ,if the skin of a certain part of the back of such a frog is gently stroked with the finger1 it immediately croaks4 ,it never croaks unless it is so stroked1 and the croak always follows the stroke1 just as the sound of a repeater follows the touching of the spring4 ,in the frog1 this 8song0 is innate--so to speak priori--and depends upon a mechanism in the brain governing the vocal apparatus1 which is set at work by the molecular change set up in the sensory nerves of the skin of the back by the contact of a foreign body4 ,in man there is also a vocal mechanism1 and the cry of an infant is in the same sense innate and priori1 inasmuch as it depends on an organic relation between its sensory nerves and the nervous mechanism which governs the vocal apparatus4 ,learning to speak1 and learning to sing1 are processes by which the vocal mechanism is set to new tunes4 ,a song which has been learned has its molecular equivalent1 which potentially represents it in the brain1 just as a musical box wound up potentially represents an overture4 ,touch the stop and the overture begins2 send a molecular impulse along the proper afferent nerve and the singer begins his song4 ,again1 the manner in which the frog1 though apparently insensible to light1 is yet1 under some circumstances1 influenced by visual images1 finds a singular parallel in the case of the ex-sergeant4 ,sitting at a table1 in one of his abnormal states1 he took up a pen1 felt for paper and ink1 and began to write a letter to his general1 in which he recommended himself for a medal1 on account of his good conduct and courage4 ,it occurred to ,dr4 ,mesnet to ascertain experimentally how far vision was concerned in this act of writing4 ,he therefore interposed a screen between the man's eyes and his hands2 under these circumstances he went on writing for a short time1 but the words became illegible1 and he finally stopped1 without manifesting any discontent4 ,on the withdrawal of the screen he began to write again where he had left off4 ,the substitution of water for ink in the inkstand had a similar result4 ,he stopped1 looked at his pen1 wiped it on his coat1 dipped it in the water1 and began again1 with the same effect4 ,on one occasion1 he began to write upon the topmost of ten superimposed sheets of paper4 ,after he had written a line or two1 this sheet was suddenly drawn away4 ,there was a slight expression of surprise1 but he continued his letter on the second sheet exactly as if it had been the first4 ,this operation was repeated five times1 so that the fifth sheet contained nothing but the writer's signature at the bottom of the page4 ,nevertheless1 when the signature was finished1 his eyes turned to the top of the blank sheet1 and he went through the form of reading over what he had written1 a movement of the lips accompanying each word2 moreover1 with his pen1 he put in such corrections as were needed1 in that part of the blank page which corresponded with the position of the words which required correction1 in the sheets which had been taken away4 ,if the five sheets had been transparent1 therefore1 they would1 when superposed1 have formed a properly written and corrected letter4 ,immediately after he had written his letter1 ,f---- got up1 walked down to the garden1 made himself a cigarette1 lighted and smoked it4 ,he was about to prepare another1 but sought in vain for his tobacco-pouch1 which had been purposely taken away4 ,the pouch was now thrust before his eyes and put under his nose1 but he neither saw nor smelt it2 but1 when it was placed in his hand1 he at once seized it1 made a fresh cigarette1 and ignited a match to light the latter4 ,the match was blown out1 and another lighted match placed close before his eyes1 but he made no attempt to take it2 and1 if his cigarette was lighted for him1 he made no attempt to smoke4 ,all this time the eyes were vacant1 and neither winked1 nor exhibited any contraction of the pupils4 ,from these and other experiments1 ,dr4 ,mesnet draws the conclusion that his patient sees some things and not others2 that the sense of sight is accessible to all things which are brought into relation with him by the sense of touch1 and1 on the contrary1 insensible to things which lie outside this relation4 ,he sees the match he holds1 and does not see any other4 ,just so the frog 8sees0 the book which is in the way of his jump1 at the same time that isolated visual impressions take no effect upon him4#ec ,as ,i have pointed out1 it is impossible to prove that ,f---- is absolutely unconscious in his abnormal state1 but it is no less impossible to prove the contrary2 and the case of the frog goes a long way to justify the assumption that1 in the abnormal state1 the man is a mere insensible machine4 ,if such facts as these had come under the knowledge of ,descartes1 would they not have formed an apt commentary upon that remarkable passage in the 8,trait de l',homme10 which ,i have quoted elsewhere1#ed but which is worth repetition8-- 8,all the functions which ,i have attributed to this machine 7the body71 as the digestion of food1 the pulsation of the heart and of the arteries2 the nutrition and the growth of the limbs2 respiration1 wakefulness1 and sleep2 the reception of light1 sounds1 odours1 flavours1 heat1 and such like qualities1 in the organs of the external senses2 the impression of the ideas of these in the organ of common sensation and in the imagination2 the retention or the impression of these ideas on the memory3 the internal movements of the appetites and the passions2 and lastly the external movements of all the limbs1 which follow so aptly1 as well the action of the objects which are presented to the senses1 as the impressions which meet in the memory1 that they imitate as nearly as possible those of a real man2 ,i desire1 ,i say1 that you should consider that these functions in the machine naturally proceed from the mere arrangement of its organs1 neither more nor less than do the movements of a clock1 or other automaton1 from that of its weights and its wheels2 so that1 so far as these are concerned1 it is not necessary to conceive any other vegetative or sensitive soul1 nor any other principle of motion or of life1 than the blood and the spirits agitated by the fire which burns continually in the heart1 and which is no wise essentially different from all the fires which exist in inanimate bodies40 ,and would ,descartes not have been justified in asking why we need deny that animals are machines1 when men1 in a state of unconsciousness1 perform1 mechanically1 actions as complicated and as seemingly rational as those of any animals8 ,but though ,i do not think that ,descartes' hypothesis can be positively refuted1 ,i am not disposed to accept it4 ,the doctrine of continuity is too well established for it to be permissible to me to suppose that any complex natural phenomenon comes into existence suddenly1 and without being preceded by simpler modifications2 and very strong arguments would be needed to prove that such complex phenomena1 as those of consciousness1 first make their appearance in man4 ,we know1 that1 in the individual man1 consciousness grows from a dim glimmer to its full light1 whether we consider the infant advancing in years1 or the adult emerging from slumber and swoon4 ,we know1 further1 that the lower animals possess1 though less developed1 that part of the brain which we have every reason to believe to be the organ of consciousness in man2 and as1 in other cases1 function and organ are proportional1 so we have a right to conclude it is with the brain2 and that the brutes1 though they may not possess our intensity of consciousness1 and though1 from the absence of language1 they can have no trains of thoughts1 but only trains of feelings1 yet have a consciousness which1 more or less distinctly1 foreshadows our own4 ,i confess that1 in view of the struggle for existence which goes on in the animal world1 and of the frightful quantity of pain with which it must be accompanied1 ,i should be glad if the probabilities were in favour of ,descartes' hypothesis2 but1 on the other hand1 considering the terrible practical consequences to domestic animals which might ensue from any error on our part1 it is as well to err on the right side1 if we err at all1 and deal with them as weaker brethren1 who are bound1 like the rest of us1 to pay their toll for living1 and suffer what is needful for the general good4 ,as ,hartley finely says1 8,we seem to be in the place of ,god to them20 and we may justly follow the precedents ,he sets in nature in our dealings with them4 ,but though we may see reason to disagree with ,descartes' hypothesis that brutes are unconscious machines1 it does not follow that he was wrong in regarding them as automata4 ,they may be more or less conscious1 sensitive1 automata2 and the view that they are such conscious machines is that which is implicitly1 or explicitly1 adopted by most persons4 ,when we speak of the actions of the lower animals being guided by instinct and not by reason1 what we really mean is that1 though they feel as we do1 yet their actions are the results of their physical organisation4 ,we believe1 in short1 that they are machines1 one part of which 7the nervous system7 not only sets the rest in motion1 and co-ordinates its movements in relation with changes in surrounding bodies1 but is provided with special apparatus1 the function of which is the calling into existence of those states of consciousness which are termed sensations1 emotions1 and ideas4 ,i believe that this generally accepted view is the best expression of the facts at present known4 ,it is experimentally demonstrable--any one who cares to run a pin into himself may perform a sufficient demonstration of the fact--that a mode of motion of the nervous system is the immediate antecedent of a state of consciousness4 ,all but the adherents of 8,occasionalism10 or of the doctrine of 8,pre-established ,harmony0 7if any such now exist71 must admit that we have as much reason for regarding the mode of motion of the nervous system as the cause of the state of consciousness1 as we have for regarding any event as the cause of another4 ,how the one phenomenon causes the other we know1 as much or as little1 as in any other case of causation2 but we have as much right to believe that the sensation is an effect of the molecular change1 as we have to believe that motion is an effect of impact2 and there is as much propriety in saying that the brain evolves sensation1 as there is in saying that an iron rod1 when hammered1 evolves heat4 ,as ,i have endeavoured to show1 we are justified in supposing that something analogous to what happens in ourselves takes place in the brutes1 and that the affections of their sensory nerves give rise to molecular changes in the brain1 which again give rise to1 or evolve1 the corresponding states of consciousness4 ,nor can there be any reasonable doubt that the emotions of brutes1 and such ideas as they possess1 are similarly dependent upon molecular brain changes4 ,each sensory impression leaves behind a record in the structure of the brain--an 8ideagenous0 molecule1 so to speak1 which is competent1 under certain conditions1 to reproduce1 in a fainter condition1 the state of consciousness which corresponds with that sensory impression2 and it is these 8ideagenous molecules0 which are the physical basis of memory4 ,it may be assumed1 then1 that molecular changes in the brain are the causes of all the states of consciousness of brutes4 ,is there any evidence that these states of consciousness may1 conversely1 cause those molecular changes which give rise to muscular motion8 ,i see no such evidence4 ,the frog walks1 hops1 swims1 and goes through his gymnastic performances quite as well without consciousness1 and consequently without volition1 as with it2 and1 if a frog1 in his natural state1 possesses anything corresponding with what we call volition1 there is no reason to think that it is anything but a concomitant of the molecular changes in the brain which form part of the series involved in the production of motion4 ,the consciousness of brutes would appear to be related to the mechanism of their body simply as a collateral product of its working1 and to be as completely without any power of modifying that working as the steam-whistle which accompanies the work of a locomotive engine is without influence upon its machinery4 ,their volition1 if they have any1 is an emotion indicative of physical changes1 not a cause of such changes4 ,this conception of the relations of states of consciousness with molecular changes in the brain--of psychoses with neuroses--does not prevent us from ascribing free will to brutes4 ,for an agent is free when there is nothing to prevent him from doing that which he desires to do4 ,if a greyhound chases a hare1 he is a free agent1 because his action is in entire accordance with his strong desire to catch the hare2 while so long as he is held back by the leash he is not free1 being prevented by external force from following his inclination4 ,and the ascription of freedom to the greyhound under the former circumstances is by no means inconsistent with the other aspect of the facts of the case--that he is a machine impelled to the chase1 and caused1 at the same time1 to have the desire to catch the game by the impression which the rays of light proceeding from the hare make upon his eyes1 and through them upon his brain4 ,much ingenious argument has1 at various times1 been bestowed upon the question3 ,how is it possible to imagine that volition1 which is a state of consciousness1 and1 as such1 has not the slightest community of nature with matter in motion1 can act upon the moving matter of which the body is composed1 as it is assumed to do in voluntary acts8 ,but if1 as is here suggested1 the voluntary acts of brutes--or1 in other words1 the acts which they desire to perform--are as purely mechanical as the rest of their actions1 and are simply accompanied by the state of consciousness called volition1 the inquiry1 so far as they are concerned1 becomes superfluous4 ,their volitions do not enter into the chain of causation of their actions at all4 ,the hypothesis that brutes are conscious automata is perfectly consistent with any view that may be held respecting the often discussed and curious question whether they have souls or not2 and1 if they have souls1 whether those souls are immortal or not4 ,it is obviously harmonious with the most literal adherence to the text of ,scripture concerning 8the beast that perisheth20 but it is not inconsistent with the amiable conviction ascribed by ,pope to his 8untutored savage10 that when he passes to the happy hunting-grounds in the sky1 8his faithful dog shall bear him company40 ,if the brutes have consciousness and no souls1 then it is clear that1 in them1 consciousness is a direct function of material changes2 while1 if they possess immaterial subjects of consciousness1 or souls1 then1 as consciousness is brought into existence only as the consequence of molecular motion of the brain1 it follows that it is an indirect product of material changes4 ,the soul stands related to the body as the bell of a clock to the works1 and consciousness answers to the sound which the bell gives out when it is struck4 ,thus far ,i have strictly confined myself to the problem with which ,i proposed to deal at starting--the automatism of brutes4 ,the question is1 ,i believe1 a perfectly open one1 and ,i feel happy in running no risk of either ,papal or ,presbyterian condemnation for the views which ,i have ventured to put forward4 ,and there are so very few interesting questions which one is1 at present1 allowed to think out scientifically--to go as far as reason leads1 and stop where evidence comes to an end--without speedily being deafened by the tattoo of 8the drum ecclesiastic0--that ,i have luxuriated in my rare freedom1 and would now willingly bring this disquisition to an end if ,i could hope that other people would go no farther4 ,unfortunately1 past experience debars me from entertaining any such hope1 even if 8444 that drum's discordant sound ,parading round and round and round10 were not1 at present1 as audible to me1 as it was to the mild poet who ventured to express his hatred of drums in general1 in that well-known couplet4 ,it will be said1 that ,i mean that the conclusions deduced from the study of the brutes are applicable to man1 and that the logical consequences of such application are fatalism1 materialism1 and atheism--whereupon the drums will beat the pas de charge4 ,one does not do battle with drummers2 but ,i venture to offer a few remarks for the calm consideration of thoughtful persons1 untrammelled by foregone conclusions1 unpledged to shore-up tottering dogmas1 and anxious only to know the true bearings of the case4 ,it is quite true that1 to the best of my judgment1 the argumentation which applies to brutes holds equally good of men2 and1 therefore1 that all states of consciousness in us1 as in them1 are immediately caused by molecular changes of the brain-substance4 ,it seems to me that in men1 as in brutes1 there is no proof that any state of consciousness is the cause of change in the motion of the matter of the organism4 ,if these positions are well based1 it follows that our mental conditions are simply the symbols in consciousness of the changes which take place automatically in the organism2 and that1 to take an extreme illustration1 the feeling we call volition is not the cause of a voluntary act1 but the symbol of that state of the brain which is the immediate cause of that act4 ,we are conscious automata1 endowed with free will in the only intelligible sense of that much-abused term--inasmuch as in many respects we are able to do as we like--but none the less parts of the great series of causes and effects which1 in unbroken continuity1 composes that which is1 and has been1 and shall be--the sum of existence4 ,as to the logical consequences of this conviction of mine1 ,i may be permitted to remark that logical consequences are the scarecrows of fools and the beacons of wise men4 ,the only question which any wise man can ask himself1 and which any honest man will ask himself1 is whether a doctrine is true or false4 ,consequences will take care of themselves2 at most their importance can only justify us in testing with extra care the reasoning process from which they result4 ,so that if the view ,i have taken did really and logically lead to fatalism1 materialism1 and atheism1 ,i should profess myself a fatalist1 materialist1 and atheist2 and ,i should look upon those who1 while they believed in my honesty of purpose and intellectual competency1 should raise a hue and cry against me1 as people who by their own admission preferred lying to truth1 and whose opinions therefore were unworthy of the smallest attention4 ,but1 as ,i have endeavoured to explain on other occasions1 ,i really have no claim to rank myself among fatalistic1 materialistic1 or atheistic philosophers4 ,not among fatalists1 for ,i take the conception of necessity to have a logical1 and not a physical foundation2 not among materialists1 for ,i am utterly incapable of conceiving the existence of matter if there is no mind in which to picture that existence2 not among atheists1 for the problem of the ultimate cause of existence is one which seems to me to be hopelessly out of reach of my poor powers4 ,of all the senseless babble ,i have ever had occasion to read1 the demonstrations of these philosophers who undertake to tell us all about the nature of ,god would be the worst1 if they were not surpassed by the still greater absurdities of the philosophers who try to prove that there is no ,god4 ,and if this personal disclaimer should not be enough1 let me further point out that a great many persons whose acuteness and learning will not be contested1 and whose ,christian piety1 and1 in some cases1 strict orthodoxy1 are above suspicion1 have held more or less definitely the view that man is a conscious automaton4 ,it is held1 for example1 in substance1 by the whole school of predestinarian theologians1 typified by ,st4 ,augustine1 ,calvin1 and ,jonathan ,edwards--the great work of the latter on the will showing in this1 as in other cases1 that the growth of physical science has introduced no new difficulties of principle into theological problems1 but has merely given visible body1 as it were1 to those which already existed4 ,among philosophers1 the pious ,geulincx and the whole school of occasionalist ,cartesians held this view2 the orthodox ,leibnitz invented the term 8automate spirituel10 and applied it to man2 the fervent ,christian1 ,hartley1 was one of the chief advocates and best expositors of the doctrine2 while another zealous apologist of ,christianity in a sceptical age1 and a contemporary of ,hartley1 ,charles ,bonnet1 the ,genevese naturalist1 has embodied the doctrine in language of such precision and simplicity1 that ,i will quote the little-known passage of his 8,essai de ,psychologie0 at length3-- 8,,another ,,hypothesis ,,concerning ,,the ,,mechanism ,,of ,,ideas4#ee 8,philosophers accustomed to judge of things by that which they are in themselves1 and not by their relation to received ideas1 would not be shocked if they met with the proposition that the soul is a mere spectator of the movements of its body3 that the latter performs of itself all that series of actions which constitutes life3 that it moves of itself3 that it is the body alone which reproduces ideas1 compares and arranges them2 which forms reasonings1 imagines and executes plans of all kinds1 etc4 ,this hypothesis1 though perhaps of an excessive boldness1 nevertheless deserves some consideration4 8,it is not to be denied that ,supreme ,power could create an automaton which should exactly imitate all the external and internal actions of man4 8,i understand by external actions1 all those movements which pass under our eyes2 ,i term internal actions1 all the motions which in the natural state cannot be observed because they take place in the interior of the body--such as the movements of digestion1 circulation1 sensation1 etc4 ,moreover1 ,i include in this category the movements which give rise to ideas1 whatever be their nature4 8,in the automaton which we are considering everything would be precisely determined4 ,everything would occur according to the rules of the most admirable mechanism3 one state would succeed another state1 one operation would lead to another operation1 according to invariable laws2 motion would become alternately cause and effect1 effect and cause2 reaction would answer to action1 and reproduction to production4 8,constructed with definite relations to the activity of the beings which compose the world1 the automaton would receive impressions from it1 and1 in faithful correspondence thereto1 it would execute a corresponding series of motions4 8,indifferent towards any determination1 it would yield equally to all1 if the first impressions did not1 so to speak1 wind up the machine and decide its operations and its course4 8,the series of movements which this automaton could execute would distinguish it from all others formed on the same model1 but which1 not having been placed in similar circumstances1 would not have experienced the same impressions1 or would not have experienced them in the same order4 8,the senses of the automaton1 set in motion by the objects presented to it1 would communicate their motion to the brain1 the chief motor apparatus of the machine4 ,this would put in action the muscles of the hands and feet1 in virtue of their secret connection with the senses4 ,these muscles1 alternately contracted and dilated1 would approximate or remove the automaton from the objects1 in the relation which they would bear to the conservation or the destruction of the machine4 8,the motions of perception and sensation which the objects would have impressed on the brain1 would be preserved in it by the energy of its mechanism4 ,they would become more vivid according to the actual condition of the automaton1 considered in itself and relatively to the objects4 8,words being only the motions impressed on the organ of hearing and that of voice1 the diversity of these movements1 their combination1 the order in which they would succeed one another1 would represent judgments1 reasoning1 and all the operations of the mind4 8,a close correspondence between the organs of the senses1 either by the opening into one another of their nervous ramifications1 or by interposed springs 7ressorts71 would establish such a connection in their working1 that1 on the occasion of the movements impressed on one of these organs1 other movements would be excited1 or would become more vivid in some of the other senses4 8,give the automaton a soul which contemplates its movements1 which believes itself to be the author of them1 which has different volitions on the occasion of the different movements1 and you will on this hypothesis construct a man4 8,but would this man be free8 ,can the feeling of our liberty1 this feeling which is so clear and so distinct and so vivid as to persuade us that we are the authors of our actions1 be conciliated with this hypothesis8 ,if it removes the difficulty which attends the conception of the action of the soul on the body1 on the other hand it leaves untouched that which meets us in endeavouring to conceive the action of the body on the soul40 ,but if ,leibnitz1 ,jonathan ,edwards1 and ,hartley--men who rank among the giants of the world of thought--could see no antagonism between the doctrine under discussion and ,christian orthodoxy1 is it not just possible that smaller folk may be wrong in making such a coil about 8logical consequences08 ,and1 seeing how large a share of this clamour is raised by the clergy of one denomination or another1 may ,i say1 in conclusion1 that it really would be well if ecclesiastical persons would reflect that ordination1 whatever deep-seated graces it may confer1 has never been observed to be followed by any visible increase in the learning or the logic of its subject4 ,making a man a ,bishop1 or entrusting him with the office of ministering to even the largest of ,presbyterian congregations1 or setting him up to lecture to a ,church congress1 really does not in the smallest degree augment such title to respect as his opinions may intrinsically possess4 ,and1 when such a man presumes on an authority which was conferred upon him for other purposes1 to sit in judgment upon matters his incompetence to deal with which is patent1 it is permissible to ignore his sacerdotal pretensions1 and to tell him1 as one would tell a mere common1 unconsecrated1 layman3 that it is not necessary for any man to occupy himself with problems of this kind unless he so choose2 life is filled full enough by the performance of its ordinary and obvious duties4 ,but that1 if a man elect to become a judge of these grave questions2 still more1 if he assume the responsibility of attaching praise or blame to his fellow-men for the conclusions at which they arrive touching them1 he will commit a sin more grievous than most breaches of the ,decalogue1 unless he avoid a lazy reliance upon the information that is gathered by prejudice and filtered through passion1 unless he go back to the prime sources of knowledge--the facts of nature1 and the thoughts of those wise men who for generations past have been her best interpreters4 ,x4 ,,on ,,sensation ,,and ,,the ,,unity ,,of ,,structure ,,of ,,sensiferous ,,organs4 ,the maxim that metaphysical inquiries are barren of result1 and that the serious occupation of the mind with them is a mere waste of time and labour1 finds much favour in the eyes of the many persons who pride themselves on the possession of sound common sense2 and we sometimes hear it enunciated by weighty authorities1 as if its natural consequence1 the suppression of such studies1 had the force of a moral obligation4 ,in this case1 however1 as in some others1 those who lay down the law seem to forget that a wise legislator will consider1 not merely whether his proposed enactment is desirable1 but whether obedience to it is possible4 ,for1 if the latter question is answered negatively1 the former is surely hardly worth debate4 ,here1 in fact1 lies the pith of the reply to those who would make metaphysics contraband of intellect4 ,whether it is desirable to place a prohibitory duty upon philosophical speculations or not1 it is utterly impossible to prevent the importation of them into the mind4 ,and it is not a little curious to observe that those who most loudly profess to abstain from such commodities are1 all the while1 unconscious consumers1 on a great scale1 of one or other of their multitudinous disguises or adulterations4 ,with mouths full of the particular kind of heavily buttered toast which they affect1 they inveigh against the eating of plain bread4 ,in truth1 the attempt to nourish the human intellect upon a diet which contains no metaphysics is about as hopeful as that of certain ,eastern sages to nourish their bodies without destroying life4 ,everybody has heard the story of the pitiless microscopist1 who ruined the peace of mind of one of these mild enthusiasts by showing him the animals moving in a drop of the water with which1 in the innocency of his heart1 he slaked his thirst2 and the unsuspecting devotee of plain common sense may look for as unexpected a shock when the magnifier of severe logic reveals the germs1 if not the full-grown shapes1 of lively metaphysical postulates rampant amidst his most positive and matter-of-fact notions4 ,by way of escape from the metaphysical ,will-o'-the-wisps generated in the marshes of literature and theology1 the serious student is sometimes bidden to betake himself to the solid ground of physical science4 ,but the fish of immortal memory1 who threw himself out of the frying-pan into the fire1 was not more ill advised than the man who seeks sanctuary from philosophical persecution within the walls of the observatory or of the laboratory4 ,it is said that 8metaphysics0 owe their name to the fact that1 in ,aristotle's works1 questions of pure philosophy are dealt with immediately after those of physics4 ,if so1 the accident is happily symbolical of the essential relations of things2 for metaphysical speculation follows as closely upon physical theory as black care upon the horseman4 ,one need but mention such fundamental1 and indeed indispensable1 conceptions of the natural philosopher as those of atoms and forces3 or that of attraction considered as action at a distance2 or that of potential energy2 or the antinomies of a vacuum and a plenum2 to call to mind the metaphysical background of physics and chemistry2 while1 in the biological sciences1 the case is still worse4 ,what is an individual among the lower plants and animals8 ,are genera and species realities or abstractions8 ,is there such a thing as ,vital ,force8 or does the name denote a mere relic of metaphysical fetichism8 ,is the doctrine of final causes legitimate or illegitimate8 ,these are a few of the metaphysical topics which are suggested by the most elementary study of biological facts4 ,but1 more than this1 it may be truly said that the roots of every system of philosophy lie deep among the facts of physiology4 ,no one can doubt that the organs and the functions of sensation are as much a part of the province of the physiologist1 as are the organs and functions of motion1 or those of digestion2 and yet it is impossible to gain an acquaintance with even the rudiments of the physiology of sensation without being led straight to one of the most fundamental of all metaphysical problems4 ,in fact1 the sensory operations have been1 from time immemorial1 the battle-ground of philosophers4 ,i have more than once taken occasion to point out that we are indebted to ,descartes1 who happened to be a physiologist as well as a philosopher1 for the first distinct enunciation of the essential elements of the true theory of sensation4 ,in later times1 it is not to the works of the philosophers1 if ,hartley and ,james ,mill are excepted1 but to those of the physiologists1 that we must turn for an adequate account of the sensory process4 ,haller's luminous1 though summary1 account of sensation in his admirable 8,prim ,line10 the first edition of which was printed in #agdg1 offers a striking contrast to the prolixity and confusion of thought which pervade ,reid's 8,inquiry10 of seventeen years' later date4#ef ,even ,sir ,william ,hamilton1 learned historian and acute critic as he was1 not only failed to apprehend the philosophical bearing of long-established physiological truths2 but1 when he affirmed that there is no reason to deny that the mind feels at the finger points1 and none to assert that the brain is the sole organ of thought1#eg he showed that he had not apprehended the significance of the revolution commenced1 two hundred years before his time1 by ,descartes1 and effectively followed up by ,haller1 ,hartley1 and ,bonnet1 in the middle of the last century4 ,in truth1 the theory of sensation1 except in one point1 is1 at the present moment1 very much where ,hartley1 led by a hint of ,sir ,isaac ,newton's1 left it1 when1 a hundred and twenty years since1 the 8,observations on ,man3 his ,frame1 his ,duty1 and his ,expectations10 was laid before the world4 ,the whole matter is put in a nutshell in the following passages of this notable book4 8,external objects impressed upon the senses occasion1 first on the nerves on which they are impressed1 and then on the brain1 vibrations of the small and1 as we may say1 infinitesimal medullary particles4 8,these vibrations are motions backwards and forwards of the small particles2 of the same kind with the oscillations of pendulums and the tremblings of the particles of sounding bodies4 ,they must be conceived to be exceedingly short and small1 so as not to have the least efficacy to disturb or move the whole bodies of the nerves or brain40#eh 8,the white medullary substance of the brain is also the immediate instrument by which ideas are presented to the mind2 or1 in other words1 whatever changes are made in this substance1 corresponding changes are made in our ideas2 and vice versa40#ei ,hartley1 like ,haller1 had no conception of the nature and functions of the grey matter of the brain4 ,but1 if for 8white medullary substance10 in the latter paragraph1 we substitute 8grey cellular substance10 ,hartley's propositions embody the most probable conclusions which are to be drawn from the latest investigations of physiologists4 ,in order to judge how completely this is the case1 it will be well to study some simple case of sensation1 and1 following the example of ,reid and of ,james ,mill1 we may begin with the sense of smell4 ,suppose that ,i become aware of a musky scent1 to which the name of 8muskiness0 may be given4 ,i call this an odour1 and ,i class it along with the feelings of light1 colours1 sounds1 tastes1 and the like1 among those phenomena which are known as sensations4 ,to say that ,i am aware of this phenomenon1 or that ,i have it1 or that it exists1 are simply different modes of affirming the same facts4 ,if ,i am asked how ,i know that it exists1 ,i can only reply that its existence and my knowledge of it are one and the same thing2 in short1 that my knowledge is immediate or intuitive1 and1 as such1 is possessed of the highest conceivable degree of certainty4 ,the pure sensation of muskiness is almost sure to be followed by a mental state which is not a sensation1 but a belief1 that there is somewhere close at hand a something on which the existence of the sensation depends4 ,it may be a musk-deer1 or a musk-rat1 or a musk-plant1 or a grain of dry musk1 or simply a scented handkerchief2 but former experience leads us to believe that the sensation is due to the presence of one or other of these objects1 and that it will vanish if the object is removed4 ,in other words1 there arises a belief in an external cause of the muskiness1 which1 in common language1 is termed an odorous body4 ,but the manner in which this belief is usually put into words is strangely misleading4 ,if we are dealing with a musk-plant1 for example1 we do not confine ourselves to a simple statement of that which we believe1 and say that the musk-plant is the cause of the sensation called muskiness2 but we say that the plant has a musky smell1 and we speak of the odour as a quality1 or property1 inherent in the plant4 ,and the inevitable reaction of words upon thought has in this case become so complete1 and has penetrated so deeply1 that when an accurate statement of the case--namely1 that muskiness1 inasmuch as the term denotes nothing but a sensation1 is a mental state1 and has no existence except as a mental phenomenon--is first brought under the notice of common-sense folks1 it is usually regarded by them as what they are pleased to call a mere metaphysical paradox and a patent example of useless subtlety4 ,yet the slightest reflection must suffice to convince any one possessed of sound reasoning faculties1 that it is as absurd to suppose that muskiness is a quality inherent in one plant1 as it would be to imagine that pain is a quality inherent in another1 because we feel pain when a thorn pricks the finger4 ,even the common-sense philosopher1 par excellence1 says of smell3 8,it appears to be a simple and original affection or feeling of the mind1 altogether inexplicable and unaccountable4 ,it is indeed impossible that it can be in any body3 it is a sensation1 and a sensation can only be in a sentient thing40#fj ,that which is true of muskiness is true of every other odour4 ,lavender-smell1 clove-smell1 garlic-smell1 are1 like 8muskiness10 names of states of consciousness1 and have no existence except as such4 ,but1 in ordinary language1 we speak of all these odours as if they were independent entities residing in lavender1 cloves1 and garlic2 and it is not without a certain struggle that the false metaphysic of so-called common sense1 thus ingrained in us1 is expelled4 ,for the present purpose1 it is unnecessary to inquire into the origin of our belief in external bodies1 or into that of the notion of causation4 ,assuming the existence of an external world1 there is no difficulty in obtaining experimental proof that1 as a general rule1 olfactory sensations are caused by odorous bodies2 and we may pass on to the next step of the inquiry--namely1 how the odorous body produces the effect attributed to it4 ,the first point to be noted here is another fact revealed by experience2 that the appearance of the sensation is governed1 not only by the presence of the odorous substance1 but by the condition of a certain part of our corporeal structure1 the nose4 ,if the nostrils are closed1 the presence of the odorous substance does not give rise to the sensation2 while1 when they are open1 the sensation is intensified by the approximation of the odorous substance to them1 and by snuffing up the adjacent air in such a manner as to draw it into the nose4 ,on the other hand1 looking at an odorous substance1 or rubbing it on the skin1 or holding it to the ear1 does not awaken the sensation4 ,thus1 it can be readily established by experiment that the perviousness of the nasal passages is1 in some way1 essential to the sensory function2 in fact1 that the organ of that function is lodged somewhere in the nasal passages4 ,and1 since odorous bodies give rise to their effects at considerable distances1 the suggestion is obvious that something must pass from them into the sense organ4 ,what is this 8something10 which plays the part of an intermediary between the odorous body and the sensory organ8 ,the oldest speculation about the matter dates back to ,democritus and the ,epicurean ,school1 and it is to be found fully stated in the fourth book of ,lucretius4 ,it comes to this3 that the surfaces of bodies are constantly throwing off excessively attenuated films of their own substance3 and that these films1 reaching the mind1 excite the appropriate sensations in it4 ,aristotle did not admit the existence of any such material films1 but conceived that it was the form of the substance1 and not its matter1 which affected sense1 as a seal impresses wax1 without losing anything in the process4 ,while many1 if not the majority1 of the ,schoolmen took up an intermediate position and supposed that a something1 which was not exactly either material or immaterial1 and which they called an 8intentional species10 effected the needful communication between the bodily cause of sensation and the mind4 ,but all these notions1 whatever may be said for or against them in general1 are fundamentally defective1 by reason of an oversight which was inevitable1 in the state of knowledge at the time in which they were promulgated4 ,what the older philosophers did not know1 and could not know1 before the anatomist and the physiologist had done their work1 is that1 between the external object and that mind in which they supposed the sensation to inhere1 there lies a physical obstacle4 ,the sense organ is not a mere passage by which the 8tenuia simulacra rerum10 or the 8intentional species0 cast off by objects1 or the 8forms0 of sensible things1 pass straight to the mind2 on the contrary1 it stands as a firm and impervious barrier1 through which no material particle of the world without can make its way to the world within4 ,let us consider the olfactory sense organ more nearly4 ,each of the nostrils leads into a passage completely separated from the other by a partition1 and these two passages place the nostrils in free communication with the back of the throat1 so that they freely transmit the air passing to the lungs when the mouth is shut1 as in ordinary breathing4 ,the floor of each passage is flat1 but its roof is a high arch1 the crown of which is seated between the orbital cavities of the skull1 which serve for the lodgment and protection of the eyes2 and it therefore lies behind the apparent limits of that feature which1 in ordinary language1 is called the nose4 ,from the side walls of the upper and back part of these arched chambers1 certain delicate plates of bone project1 and these1 as well as a considerable part of the partition between the two chambers1 are covered by a fine1 soft1 moist membrane4 ,it is to this 8,schneiderian10 or olfactory1 membrane that odorous bodies must obtain direct access1 if they are to give rise to their appropriate sensations2 and it is upon the relatively large surface1 which the olfactory membrane offers1 that we must seek for the seat of the organ of the olfactory sense4 ,the only essential part of that organ consists of a multitude of minute rod-like bodies1 set perpendicularly to the surface of the membrane1 and forming a part of the cellular coat1 or epithelium1 which covers the olfactory membrane1 as the epidermis covers the skin4 ,in the case of the olfactory sense1 there can be no doubt that the ,democritic hypothesis1 at any rate for such odorous substances as musk1 has a good foundation4 ,infinitesimal particles of musk fly off from the surface of the odorous body1 and1 becoming diffused through the air1 are carried into the nasal passages1 and thence into the olfactory chambers1 where they come into contact with the filamentous extremities of the delicate olfactory epithelium4 ,but this is not all4 ,the 8mind0 is not1 so to speak1 upon the other side of the epithelium4 ,on the contrary1 the inner ends of the olfactory cells are connected with nerve fibres1 and these nerve fibres1 passing into the cavity of the skull1 at length end in a part of the brain1 the olfactory sensorium4 ,it is certain that the integrity of each1 and the physical inter-connection of all these three structures1 the epithelium of the sensory organ1 the nerve fibres1 and the sensorium1 are essential conditions of ordinary sensation4 ,that is to say1 the air in the olfactory chambers may be charged with particles of musk2 but1 if either the epithelium1 or the nerve fibres1 or the sensorium is injured1 or if they are physically disconnected from one another1 sensation will not arise4 ,moreover1 the epithelium may be said to be receptive1 the nerve fibres transmissive1 and the sensorium sensifacient4 ,for1 in the act of smelling1 the particles of the odorous substance produce a molecular change 7which ,hartley was in all probability right in terming a vibration7 in the epithelium1 and this change being transmitted to the nerve fibres1 passes along them with a measurable velocity1 and1 finally reaching the sensorium1 is immediately followed by the sensation4 ,thus1 modern investigation supplies a representative of the ,epicurean simulacra in the volatile particles of the musk2 but it also gives us the stamp of the particles on the olfactory epithelium1 without any transmission of matter1 as the equivalent of the ,aristotelian 8form20 while1 finally1 the modes of motion of the molecules of the olfactory cells1 of the nerve1 and of the cerebral sensorium1 which are ,hartley's vibrations1 may stand very well for a double of the 8intentional species0 of the ,schoolmen4 ,and this last remark is not intended merely to suggest a fanciful parallel2 for1 if the cause of the sensation is1 as analogy suggests1 to be sought in the mode of motion of the object of sense1 then it is quite possible that the particular mode of motion of the object is reproduced in the sensorium2 exactly as the diaphragm of a telephone reproduces the mode of motion taken up at its receiving end4 ,in other words1 the secondary 8intentional species0 may be1 as the ,schoolmen thought the primary one was1 the last link between matter and mind4 ,none the less1 however1 does it remain true that no similarity exists1 nor indeed is conceivable1 between the cause of the sensation and the sensation4 ,attend as closely to the sensations of muskiness1 or any other odour1 as we will1 no trace of extension1 resistance1 or motion is discernible in them4 ,they have no attribute in common with those which we ascribe to matter2 they are1 in the strictest sense of the words1 immaterial entities4 ,thus1 the most elementary study of sensation justifies ,descartes' position1 that we know more of mind than we do of body2 that the immaterial world is a firmer reality than the material4 ,for the sensation 8muskiness0 is known immediately4 ,so long as it persists1 it is a part of what we call our thinking selves1 and its existence lies beyond the possibility of doubt4 ,the knowledge of an objective or material cause of the sensation1 on the other hand1 is mediate2 it is a belief as contradistinguished from an intuition2 and it is a belief which1 in any given instance of sensation1 may1 by possibility1 be devoid of foundation4 ,for odours1 like other sensations1 may arise from the occurrence of the appropriate molecular changes in the nerve or in the sensorium1 by the operation of a cause distinct from the affection of the sense organ by an odorous body4 ,such 8subjective0 sensations are as real existences as any others1 and as distinctly suggest an external odorous object as their cause2 but the belief thus generated is a delusion4 ,and1 if beliefs are properly termed 8testimonies of consciousness10 then undoubtedly the testimony of consciousness may be1 and often is1 untrustworthy4 ,another very important consideration arises out of the facts as they are now known4 ,that which1 in the absence of a knowledge of the physiology of sensation1 we call the cause of the smell1 and term the odorous object1 is only such1 mediately1 by reason of its emitting particles which give rise to a mode of motion in the sense organ4 ,the sense organ1 again1 is only a mediate cause by reason of its producing a molecular change in the nerve fibre2 while this last change is also only a mediate cause of sensation1 depending1 as it does1 upon the change which it excites in the sensorium4 ,the sense organ1 the nerve1 and the sensorium1 taken together1 constitute the sensiferous apparatus4 ,they make up the thickness of the wall between the mind1 as represented by the sensation 8muskiness10 and the object1 as represented by the particle of musk in contact with the olfactory epithelium4 ,it will be observed that the sensiferous wall and the external world are of the same nature2 whatever it is that constitutes them both is expressible in terms of matter and motion4 ,whatever changes take place in the sensiferous apparatus are continuous with1 and similar to1 those which take place in the external world4#fa ,but1 with the sensorium1 matter and motion come to an end2 while phenomena of another order1 or immaterial states of consciousness1 make their appearance4 ,how is the relation between the material and the immaterial phenomena to be conceived8 ,this is the metaphysical problem of problems1 and the solutions which have been suggested have been made the corner-stones of systems of philosophy4 ,three mutually irreconcilable readings of the riddle have been offered4 ,the first is1 that an immaterial substance of mind exists2 and that it is affected by the mode of motion of the sensorium in such a way as to give rise to the sensation4 ,the second is1 that the sensation is a direct effect of the mode of motion of the sensorium1 brought about without the intervention of any substance of mind4 ,the third is1 that the sensation is neither directly nor indirectly an effect of the mode of motion of the sensorium1 but that it has an independent cause4 ,properly speaking1 therefore1 it is not an effect of the motion of the sensorium1 but a concomitant of it4 ,as none of these hypotheses is capable of even an approximation to demonstration1 it is almost needless to remark that they have been severally held with tenacity and advocated with passion4 ,i do not think it can be said of any of the three that it is inconceivable1 or that it can be assumed on priori grounds to be impossible4 ,consider the first1 for example2 an immaterial substance is perfectly conceivable4 ,in fact1 it is obvious that1 if we possessed no sensations but those of smell and hearing1 we should be unable to conceive a material substance4 ,we might have a conception of time1 but could have none of extension1 or of resistance1 or of motion4 ,and without the three latter conceptions no idea of matter could be formed4 ,our whole knowledge would be limited to that of a shifting succession of immaterial phenomena4 ,but1 if an immaterial substance may exist1 it may have any conceivable properties2 and sensation may be one of them4 ,all these propositions may be affirmed with complete dialectic safety1 inasmuch as they cannot possibly be disproved2 but neither can a particle of demonstrative evidence be offered in favour of the existence of an immaterial substance4 ,as regards the second hypothesis1 it certainly is not inconceivable1 and therefore it may be true1 that sensation is the direct effect of certain kinds of bodily motion4 ,it is just as easy to suppose this as to suppose1 on the former hypothesis1 that bodily motion affects an immaterial substance4 ,but neither is it susceptible of proof4 ,and1 as to the third hypothesis1 since the logic of induction is in no case competent to prove that events apparently standing in the relation of cause and effect may not both be effects of a common cause--that also is as safe from refutation1 if as incapable of demonstration1 as the other two4 ,in my own opinion1 neither of these speculations can be regarded seriously as anything but a more or less convenient working hypothesis4 ,but1 if ,i must choose among them1 ,i take the 8law of parsimony0 for my guide1 and select the simplest--namely1 that the sensation is the direct effect of the mode of motion of the sensorium4 ,it may justly be said that this is not the slightest explanation of sensation2 but then am ,i really any the wiser1 if ,i say that a sensation is an activity 7of which ,i know nothing7 of a substance of mind 7of which also ,i know nothing78 ,or1 if ,i say that the ,deity causes the sensation to arise in my mind immediately after ,he has caused the particles of the sensorium to move in a certain way1 is anything gained8 ,in truth1 a sensation1 as we have already seen1 is an intuition--a part of immediate knowledge4 ,as such1 it is an ultimate fact and inexplicable2 and all that we can hope to find out about it1 and that indeed is worth finding out1 is its relation to other natural facts4 ,that relation appears to me to be sufficiently expressed1 for all practical purposes1 by saying that sensation is the invariable consequent of certain changes in the sensorium--or1 in other words1 that1 so far as we know1 the change in the sensorium is the cause of the sensation4 ,i permit myself to imagine that the untutored1 if noble1 savage of 8common sense0 who has been misled into reading thus far by the hope of getting positive solid information about sensation1 giving way to not unnatural irritation1 may here interpellate3 8,the upshot of all this long disquisition is that we are profoundly ignorant4 ,we knew that to begin with1 and you have merely furnished another example of the emptiness and uselessness of metaphysics40 ,but ,i venture to reply1 ,pardon me1 you were ignorant1 but you did not know it4 ,on the contrary1 you thought you knew a great deal1 and were quite satisfied with the particularly absurd metaphysical notions which you were pleased to call the teachings of common sense4 ,you thought that your sensations were properties of external things1 and had an existence outside of yourself4 ,you thought that you knew more about material than you do about immaterial existences4 ,and if1 as a wise man has assured us1 the knowledge of what we don't know is the next best thing to the knowledge of what we do know1 this brief excursion into the province of philosophy has been highly profitable4 ,of all the dangerous mental habits1 that which schoolboys call 8cocksureness0 is probably the most perilous2 and the inestimable value of metaphysical discipline is that it furnishes an effectual counterpoise to this evil proclivity4 ,whoso has mastered the elements of philosophy knows that the attribute of unquestionable certainty appertains only to the existence of a state of consciousness so long as it exists2 all other beliefs are mere probabilities of a higher or lower order4 ,sound metaphysic is an amulet which renders its possessor proof alike against the poison of superstition and the counter-poison of nihilism2 by showing that the affirmations of the former and the denials of the latter alike deal with matters about which1 for lack of evidence1 nothing can be either affirmed or denied4 ,i have dwelt at length upon the nature and origin of our sensations of smell1 on account of the comparative freedom of the olfactory sense from the complications which are met with in most of the other senses4 ,sensations of taste1 however1 are generated in almost as simple a fashion as those of smell4 ,in this case1 the sense organ is the epithelium which covers the tongue and the palate3 and which sometimes1 becoming modified1 gives rise to peculiar organs termed 8gustatory bulbs10 in which the epithelial cells elongate and assume a somewhat rod-like form4 ,nerve fibres connect the sensory organ with the sensorium1 and tastes or flavours are states of consciousness caused by the change of molecular state of the latter4 ,in the case of the sense of touch there is often no sense organ distinct from the general epidermis4 ,but many fishes and amphibia exhibit local modifications of the epidermic cells which are sometimes extraordinarily like the gustatory bulbs2 more commonly1 both in lower and higher animals1 the effect of the contact of external bodies is intensified by the development of hair-like filaments1 or of true hairs1 the bases of which are in immediate relation with the ends of the sensory nerves4 ,every one must have noticed the extreme delicacy of the sensations produced by the contact of bodies with the ends of the hairs of the head2 and the 8whiskers0 of cats owe their functional importance to the abundant supply of nerves to the follicles in which their bases are lodged4 ,what part1 if any1 the so-called 8tactile corpuscles10 8end bulbs10 and 8,pacinian bodies10 play in the mechanism of touch is unknown4 ,if they are sense organs1 they are exceptional in character1 in so far as they do not appear to be modifications of the epidermis4 ,nothing is known respecting the organs of those sensations of resistance which are grouped under the head of the muscular sense2 nor of the sensations of warmth and cold2 nor of that very singular sensation which we call tickling4 ,in the case of heat and cold1 the organism not only becomes affected by external bodies1 far more remote than those which affect the sense of smell2 but the ,democritic hypothesis is obviously no longer permissible4 ,when the direct rays of the sun fall upon the skin1 the sensation of heat is certainly not caused by 8attenuated films0 thrown off from that luminary1 but is due to a mode of motion which is transmitted to us4 ,in ,aristotelian phrase1 it is the form without the matter of the sun which stamps the sense organ2 and this1 translated into modern language1 means nearly the same thing as ,hartley's vibrations4 ,thus we are prepared for what happens in the case of the auditory and the visual senses4 ,for neither the ear1 nor the eye1 receives anything but the impulses or vibrations originated by sonorous or luminous bodies4 ,nevertheless1 the receptive apparatus still consists of nothing but specially modified epithelial cells4 ,in the labyrinth of the ear of the higher animals1 the free ends of these cells terminate in excessively delicate hair-like filaments2 while1 in the lower forms of auditory organ1 its free surface is beset with delicate hairs like those of the surface of the body1 and the transmissive nerves are connected with the bases of these hairs4 ,thus there is an insensible gradation in the forms of the receptive apparatus1 from the organ of touch1 on the one hand1 to those of taste and smell2 and1 on the other hand1 to that of hearing4 ,even in the case of the most refined of all the sense organs1 that of vision1 the receptive apparatus departs but little from the general type4 ,the only essential constituent of the visual sense organ is the retina1 which forms so small a part of the eyes of the higher animals2 and the simplest eyes are nothing but portions of the integument1 in which the cells of the epidermis have become converted into glassy rod-like retinal corpuscles4 ,the outer ends of these are turned towards the light2 their sides are more or less extensively coated with a dark pigment1 and their inner ends are connected with the transmissive nerve fibres4 ,the light1 impinging on these visual rods1 produces a change in them which is communicated to the nerve fibres1 and1 being transmitted to the sensorium1 gives rise to the sensation--if indeed all animals which possess eyes are endowed with what we understand as sensation4 ,in the higher animals1 a complicated apparatus of lenses1 arranged on the principle of a camera obscura1 serves at once to concentrate and to individualise the pencils of light proceeding from external bodies4 ,but the essential part of the organ of vision is still a layer of cells1 which have the form of rods with truncated or conical ends4 ,by what seems a strange anomaly1 however1 the glassy ends of these are turned not towards1 but away from1 the light2 and the latter has to traverse the layer of nervous tissues with which their outer ends are connected1 before it can affect them4 ,moreover1 the rods and cones of the vertebrate retina are so deeply seated1 and in many respects so peculiar in character1 that it appears impossible1 at first sight1 that they can have anything to do with that epidermis of which gustatory and tactile1 and at any rate the lower forms of auditory and visual1 organs are obvious modifications4 ,whatever be the apparent diversities among the sensiferous apparatuses1 however1 they share certain common characters4 ,each consists of a receptive1 a transmissive1 and a sensificatory portion4 ,the essential part of the first is an epithelium1 of the second1 nerve fibres1 of the third1 a part of the brain2 the sensation is always the consequence of the mode of motion excited in the receptive1 and sent along the transmissive1 to the sensificatory part of the sensiferous apparatus4 ,and1 in all the senses1 there is no likeness whatever between the object of sense1 which is matter in motion1 and the sensation1 which is an immaterial phenomenon4 ,on the hypothesis which appears to me to be the most convenient1 sensation is a product of the sensiferous apparatus caused by certain modes of motion which are set up in it by impulses from without4 ,the sensiferous apparatuses are1 as it were1 factories1 all of which at the one end receive raw materials of a similar kind--namely1 modes of motion--while1 at the other1 each turns out a special product1 the feeling which constitutes the kind of sensation characteristic of it4 ,or1 to make use of a closer comparison1 each sensiferous apparatus is comparable to a musical-box wound up2 with as many tunes as there are separate sensations4 ,the object of a simple sensation is the agent which presses down the stop of one of these tunes1 and the more feeble the agent1 the more delicate must be the mobility of the stop4#fb ,but1 if this be true1 if the recipient part of the sensiferous apparatus is1 in all cases1 merely a mechanism affected by coarser or finer kinds of material motion1 we might expect to find that all sense organs are fundamentally alike1 and result from the modification of the same morphological elements4 ,and this is exactly what does result from all recent histological and embryological investigations4 ,it has been seen that the receptive part of the olfactory apparatus is a slightly modified epithelium1 which lines an olfactory chamber deeply seated between the orbits in adult human beings4 ,but1 if we trace back the nasal chambers to their origin in the embryo1 we find1 that1 to begin with1 they are mere depressions of the skin of the fore part of the head1 lined by a continuation of the general epidermis4 ,these depressions become pits1 and the pits1 by the growth of the adjacent parts1 gradually acquire the position which they finally occupy4 ,the olfactory organ1 therefore1 is a specially modified part of the general integument4 ,the human ear would seem to present greater difficulties4 ,for the essential part of the sense organ1 in this case1 is the membranous labyrinth1 a bag of complicated form1 which lies buried in the depths of the floor of the skull1 and is surrounded by dense and solid bone4 ,here1 however1 recourse to the study of development readily unravels the mystery4 ,shortly after the time when the olfactory organ appears1 as a depression of the skin on the side of the fore part of the head1 the auditory organ appears as a similar depression on the side of its back part4 ,the depression1 rapidly deepening1 becomes a small pouch2 and then1 the communication with the exterior becoming shut off1 the pouch is converted into a closed bag1 the epithelial lining of which is a part of the general epidermis segregated from the rest4 ,the adjacent tissues1 changing first into cartilage and then into bone1 enclose the auditory sac in a strong case1 in which it undergoes its further metamorphoses2 while the drum1 the ear bones1 and the external ear1 are superadded by no less extraordinary modifications of the adjacent parts4 ,still more marvellous is the history of the development of the organ of vision4 ,in the place of the eye1 as in that of the nose and that of the ear1 the young embryo presents a depression of the general integument2 but1 in man and the higher animals1 this does not give rise to the proper sensory organ1 but only to part of the accessory structures concerned in vision4 ,in fact1 this depression1 deepening and becoming converted into a shut sac1 produces only the cornea1 the aqueous humour1 and the crystalline lens of the perfect eye4 ,the retina is added to this by the outgrowth of the wall of a portion of the brain into a sort of bag1 or sac1 with a narrow neck1 the convex bottom of which is turned outwards1 or towards the crystalline lens4 ,as the development of the eye proceeds1 the convex bottom of the bag becomes pushed in1 so that it gradually obliterates the cavity of the sac1 the previously convex wall of which becomes deeply concave4 ,the sac of the brain is now like a double nightcap ready for the head1 but the place which the head would occupy is taken by the vitreous humour1 while the layer of nightcap next it becomes the retina4 ,the cells of this layer which lie farthest from the vitreous humour1 or1 in other words1 bound the original cavity of the sac1 are metamorphosed into the rods and cones4 ,suppose now that the sac of the brain could be brought back to its original form2 then the rods and cones would form part of the lining of a side pouch of the brain4 ,but one of the most wonderful revelations of embryology is the proof of the fact that the brain itself is1 at its first beginning1 merely an infolding of the epidermic layer of the general integument4 ,hence it follows that the rods and cones of the vertebrate eye are modified epidermic cells1 as much as the crystalline cones of the insect or crustacean eye are2 and that the inversion of the position of the former in relation to light arises simply from the roundabout way in which the vertebrate retina is developed4 ,thus all the higher sense organs start from one foundation1 and the receptive epithelium of the eye1 or of the ear1 is as much modified epidermis as is that of the nose4 ,the structural unity of the sense organs is the morphological parallel to their identity of physiological function1 which1 as we have seen1 is to be impressed by certain modes of motion2 and they are fine or coarse1 in proportion to the delicacy or the strength of the impulses by which they are to be affected4 ,in ultimate analysis1 then1 it appears that a sensation is the equivalent in terms of consciousness for a mode of motion of the matter of the sensorium4 ,but1 if inquiry is pushed a stage farther1 and the question is asked1 ,what then do we know about matter and motion8 there is but one reply possible4 ,all that we know about motion is that it is a name for certain changes in the relations of our visual1 tactile1 and muscular sensations2 and all that we know about matter is that it is the hypothetical substance of physical phenomena--the assumption of the existence of which is as pure a piece of metaphysical speculation as is that of the existence of the substance of mind4 ,our sensations1 our pleasures1 our pains1 and the relations of these1 make up the sum total of the elements of positive1 unquestionable knowledge4 ,we call a large section of these sensations and their relations matter and motion2 the rest we term mind and thinking2 and experience shows that there is a certain constant order of succession between some of the former and some of the latter4 ,this is all that just metaphysical criticism leaves of the idols set up by the spurious metaphysics of vulgar common sense4 ,it is consistent either with pure ,materialism1 or with pure ,idealism1 but it is neither4 ,for the ,idealist1 not content with declaring the truth that our knowledge is limited to facts of consciousness1 affirms the wholly unprovable proposition that nothing exists beyond these and the substance of mind4 ,and1 on the other hand1 the ,materialist1 holding by the truth that1 for anything that appears to the contrary1 material phenomena are the causes of mental phenomena1 asserts his unprovable dogma1 that material phenomena and the substance of matter are the sole primary existences4 ,strike out the propositions about which neither controversialist does or can know anything1 and there is nothing left for them to quarrel about4 ,make a desert of the ,unknowable1 and the divine ,astra of philosophic peace will commence her blessed reign4 ,,xi4 ,,evolution ,,in ,,biology4 ,in the former half of the eighteenth century1 the term 8evolution0 was introduced into biological writings1 in order to denote the mode in which some of the most eminent physiologists of that time conceived that the generation of living things took place2 in opposition to the hypothesis advocated1 in the preceding century1 by ,harvey in that remarkable work#fc which would give him a claim to rank among the founders of biological science1 even had he not been the discoverer of the circulation of the blood4 ,one of ,harvey's prime objects is to defend and establish1 on the basis of direct observation1 the opinion already held by ,aristotle2 that1 in the higher animals at any rate1 the formation of the new organism by the process of generation takes place1 not suddenly1 by simultaneous accretion of rudiments of all1 or of the most important1 of the organs of the adult2 nor by sudden metamorphosis of a formative substance into a miniature of the whole1 which subsequently grows2 but by epigenesis1 or successive differentiation of a relatively homogeneous rudiment into the parts and structures which are characteristic of the adult4 8,et prim1 quidem1 quoniam per epigenesin sive partium superexorientium additamentum pullum fabricari certum est3 qunam pars ante alias omnes exstruatur1 et quid de illa ejusque generandi modo observandum veniat1 dispiciemus4 ,ratum sane est et in ovo manifest apparet quod ,aristoteles de perfectorum animalium generatione enuntiat3 nimirum1 non omnes partes simul fieri1 sed ordine aliam post aliam2 primmque existere particulam genitalem1 cujus virtute postea 7tanquam ex principio quodam7 reliqu omnes partes prosiliant4 ,qualem in plantarum seminibus 7fabis1 put1 aut glandibus7 gemmam sive apicem protuberantem cernimus1 totius futur arboris principium4 ,estque hc particula velut filius emancipatus seorsumque collocatus1 et principium per se vivens2 unde postea membrorum ordo describitur2 et qucunque ad absolvendum animal pertinent1 disponuntur4#fd ,quoniam enim nulla pars se ipsam generat2 sed postquam generata est1 se ipsam jam auget2 ideo eam primm oriri necesse est1 qu principium augendi contineat 7sive enim planta1 sive animal est1 que omnibus inest quod vim habeat vegetandi1 sive nutriendi71#fe simulque reliquas omnes partes suo quamque ordine distinguat et formet2 proindeque in eadem primogenita particula anima primario inest1 sensus1 motusque1 et totius vit auctor et principium40 7,exercitatio #ea47 ,harvey proceeds to contrast this view with that of the 8,medici10 or followers of ,hippocrates and ,galen1 who1 8badly philosophising10 imagined that the brain1 the heart1 and the liver were simultaneously first generated in the form of vesicles2 and1 at the same time1 while expressing his agreement with ,aristotle in the principle of epigenesis1 he maintains that it is the blood which is the primal generative part1 and not1 as ,aristotle thought1 the heart4 ,in the latter part of the seventeenth century1 the doctrine of epigenesis1 thus advocated by ,harvey1 was controverted1 on the ground of direct observation1 by ,malpighi1 who affirmed that the body of the chick is to be seen in the egg1 before the punctum sanguineum makes its appearance4 ,but1 from this perfectly correct observation a conclusion which is by no means warranted was drawn2 namely1 that the chick1 as a whole1 really exists in the egg antecedently to incubation2 and that what happens in the course of the latter process is no addition of new parts1 8alias post alias natas10 as ,harvey puts it1 but a simple expansion1 or unfolding1 of the organs which already exist1 though they are too small and inconspicuous to be discovered4 ,the weight of ,malpighi's observations therefore fell into the scale of that doctrine which ,harvey terms metamorphosis1 in contradistinction to epigenesis4 ,the views of ,malpighi were warmly welcomed1 on philosophical grounds1 by ,leibnitz1#ff who found in them a support to his hypothesis of monads1 and by ,malebranche2#fg while1 in the middle of the eighteenth century1 not only speculative considerations1 but a great number of new and interesting observations on the phenomena of generation1 led the ingenious ,bonnet1 and ,haller1#fh the first physiologist of the age1 to adopt1 advocate1 and extend them4 ,bonnet affirms that1 before fecundation1 the hen's egg contains an excessively minute but complete chick2 and that fecundation and incubation simply cause this germ to absorb nutritious matters1 which are deposited in the interstices of the elementary structures of which the miniature chick1 or germ1 is made up4 ,the consequence of this intussusceptive growth is the 8development0 or 8evolution0 of the germ into the visible bird4 ,thus an organised individual 7tout organis7 8is a composite body consisting of the original1 or elementary1 parts and of the matters which have been associated with them by the aid of nutrition20 so that1 if these matters could be extracted from the individual 7tout71 it would1 so to speak1 become concentrated in a point1 and would thus be restored to its primitive condition of a germ2 8just as by extracting from a bone the calcareous substance which is the source of its hardness1 it is reduced to its primitive state of gristle or membrane40#fi 8,evolution0 and 8development0 are1 for ,bonnet1 synonymous terms2 and since by 8evolution0 he means simply the expansion of that which was invisible into visibility1 he was naturally led to the conclusion1 at which ,leibnitz had arrived by a different line of reasoning1 that no such thing as generation1 in the proper sense of the word1 exists in nature4 ,the growth of an organic being is simply a process of enlargement1 as a particle of dry gelatine may be swelled up by the intussusception of water2 its death is a shrinkage1 such as the swelled jelly might undergo on desiccation4 ,nothing really new is produced in the living world1 but the germs which develop have existed since the beginning of things2 and nothing really dies1 but1 when what we call death takes place1 the living thing shrinks back into its germ state4#gj ,the two parts of ,bonnet's hypothesis1 namely1 the doctrine that all living things proceed from pre-existing germs1 and that these contain1 one inclosed within the other1 the germs of all future living things1 which is the hypothesis of 8embotement20 and the doctrine that every germ contains in miniature all the organs of the adult1 which is the hypothesis of evolution or development1 in the primary senses of these words1 must be carefully distinguished4 ,in fact1 while holding firmly by the former1 ,bonnet more or less modified the latter in his later writings1 and1 at length1 he admits that a 8germ0 need not be an actual miniature of the organism2 but that it may be merely an 8original preformation0 capable of producing the latter4#ga ,but1 thus defined1 the germ is neither more nor less than the 8particula genitalis0 of ,aristotle1 or the 8primordium vegetale0 or 8ovum0 of ,harvey2 and the 8evolution0 of such a germ would not be distinguishable from 8epigenesis40 ,supported by the great authority of ,haller1 the doctrine of evolution1 or development1 prevailed throughout the whole of the eighteenth century1 and ,cuvier appears to have substantially adopted ,bonnet's later views1 though probably he would not have gone all lengths in the direction of 8embotement40 ,in a well-known note to ,laurillards' 8loge10 prefixed to the last edition of the 8,ossemens fossiles10 the 8radical de l'tre0 is much the same thing as ,aristotle's 8particula genitalis0 and ,harvey's 8ovum40#gb ,bonnet's eminent contemporary1 ,buffon1 held nearly the same views with respect to the nature of the germ1 and expresses them even more confidently4#gc 8,ceux qui ont cru que le cur toit le premier form1 se sont tromps2 ceux qui disent que c'est le sang se trompent aussi3 tout est form en mme temps4 ,si l'on ne consulte que l'observation1 le poulet se voit dans l'uf avant qui'il ait t couv40 8,j'ai ouvert une grande quantit d'ufs differens temps avant et aprs l'incubation1 et je me suis convaincu par mes yeux que le poulet existe en entier dans le milieu de la cicatricule au moment qu'il sort du corps de la poule40#gd ,the 8moule intrieur0 of ,buffon is the aggregate of elementary parts which constitute the individual1 and is thus the equivalent of ,bonnet's germ1#ge as defined in the passage cited above4 ,but ,buffon further imagined that innumerable 8molecules organiques0 are dispersed throughout the world1 and that alimentation consists in the appropriation by the parts of an organism of those molecules which are analogous to them4 ,growth1 therefore1 was1 on this hypothesis1 a process partly of simple evolution1 and partly of what has been termed 8syngenesis40 ,buffon's opinion is1 in fact1 a sort of combination of views1 essentially similar to those of ,bonnet1 with others1 somewhat similar to those of the 8,medici0 whom ,harvey condemns4 ,the 8molecules organiques0 are physical equivalents of ,leibnitz's 8monads40 ,it is a striking example of the difficulty of getting people to use their own powers of investigation accurately1 that this form of the doctrine of evolution should have held its ground so long2 for it was thoroughly and completely exploded1 not long after its enunciation1 by ,caspar ,friederich ,wolff1 who in his 8,theoria ,generationis10 published in #agei1 placed the opposite theory of epigenesis upon the secure foundation of fact1 from which it has never been displaced4 ,but ,wolff had no immediate successors4 ,the school of ,cuvier was lamentably deficient in embryologists2 and it was only in the course of the first thirty years of the present century1 that ,prvost and ,dumas in ,france1 and1 later on1 ,dllinger1 ,pander1 ,von ,br1 ,rathke1 and ,remak in ,germany1 founded modern embryology2 while1 at the same time1 they proved the utter incompatibility of the hypothesis of evolution1 as formulated by ,bonnet and ,haller1 with easily demonstrable facts4 ,nevertheless1 though the conceptions originally denoted by 8evolution0 and 8development0 were shown to be untenable1 the words retained their application to the process by which the embryos of living beings gradually make their appearance2 and the terms 8,development10 8,entwickelung10 and 8,evolutio10 are now indiscriminately used for the series of genetic changes exhibited by living beings1 by writers who would emphatically deny that 8,development0 or 8,entwickelung0 or 8,evolutio10 in the sense in which these words were usually employed by ,bonnet or by ,haller1 ever occurs4 ,evolution1 or development1 is1 in fact1 at present employed in biology as a general name for the history of the steps by which any living being has acquired the morphological and the physiological characters which distinguish it4 ,as civil history may be divided into biography1 which is the history of individuals1 and universal history1 which is the history of the human race1 so evolution falls naturally into two categories1--the evolution of the individual1 and the evolution of the sum of living beings4 ,it will be convenient to deal with the modern doctrine of evolution under these two heads4 ,i4 ,the ,evolution of the ,individual4 ,no exception is1 at this time1 known to the general law1 established upon an immense multitude of direct observations1 that every living thing is evolved from a particle of matter in which no trace of the distinctive characters of the adult form of that living thing is discernible4 ,this particle is termed a germ4 ,harvey#gf says-- 8,omnibus viventibus primordium insit1 ex quo et a quo proveniant4 ,liceat hoc nobis primordium vegetale nominare2 nempe substantiam quandam corpoream vitam habentem potenti2 vel quoddam per se existens1 quod aptum sit1 in vegetativam formam1 ab interno principio operante1 mutari4 ,quale nempe primordium1 ovum est et plantarum semen2 tale etiam viviparorum conceptus1 et insectorum vermis ab ,aristotele dictus3 diversa scilicet diversorum viventium primordia40 ,the definition of a germ as 8matter potentially alive1 and having within itself the tendency to assume a definite living form10 appears to meet all the requirements of modern science4 ,for1 notwithstanding it might be justly questioned whether a germ is not merely potentially1 but rather actually1 alive1 though its vital manifestations are reduced to a minimum1 the term 8potential0 may fairly be used in a sense broad enough to escape the objection4 ,and the qualification of 8potential0 has the advantage of reminding us that the great characteristic of the germ is not so much what it is1 but what it may1 under suitable conditions1 become4 ,harvey shared the belief of ,aristotle--whose writings he so often quotes1 and of whom he speaks as his precursor and model1 with the generous respect with which one genuine worker should regard another--that such germs may arise by a process of 8equivocal generation0 out of not-living matter2 and the aphorism so commonly ascribed to him1 8omne vivum ex ovo10 and which is indeed a fair summary of his reiterated assertions1 though incessantly employed against the modern advocates of spontaneous generation1 can be honestly so used only by those who have never read a score of pages of the 8,exercitationes40 ,harvey1 in fact1 believed as implicitly as ,aristotle did in the equivocal generation of the lower animals4 ,but1 while the course of modern investigation has only brought out into greater prominence the accuracy of ,harvey's conception of the nature and mode of development of germs1 it has as distinctly tended to disprove the occurrence of equivocal generation1 or abiogenesis1 in the present course of nature4 ,in the immense majority of both plants and animals1 it is certain that the germ is not merely a body in which life is dormant or potential1 but that it is itself simply a detached portion of the substance of a pre-existing living body2 and the evidence has yet to be adduced which will satisfy any cautious reasoner that 8omne vivum ex vivo0 is not as well-established a law of the existing course of nature as 8omne vivum ex ovo40 ,in all instances which have yet been investigated1 the substance of this germ has a peculiar chemical composition1 consisting of at fewest four elementary bodies1 viz4 carbon1 hydrogen1 oxygen1 and nitrogen1 united into the ill-defined compound known as protein1 and associated with much water1 and very generally1 if not always1 with sulphur and phosphorus in minute proportions4 ,moreover1 up to the present time1 protein is known only as a product and constituent of living matter4 ,again1 a true germ is either devoid of any structure discernible by optical means1 or1 at most1 it is a simple nucleated cell4#gg ,in all cases1 the process of evolution consists in a succession of changes of the form1 structure1 and functions of the germ1 by which it passes1 step by step1 from an extreme simplicity1 or relative homogeneity1 of visible structure1 to a greater or less degree of complexity or heterogeneity2 and the course of progressive differentiation is usually accompanied by growth1 which is effected by intussusception4 ,this intussusception1 however1 is a very different process from that imagined either by ,buffon1 or by ,bonnet4 ,the substance by the addition of which the germ is enlarged is1 in no case1 simply absorbed ready-made from the not-living world and packed between the elementary constituents of the germ1 as ,bonnet imagined2 still less does it consist of the 8molecules organiques0 of ,buffon4 ,the new material is1 in great measure1 not only absorbed but assimilated1 so that it becomes part and parcel of the molecular structure of the living body into which it enters4 ,and1 so far from the fully developed organism being simply the germ plus the nutriment which it has absorbed1 it is probable that the adult contains neither in form1 nor in substance1 more than an inappreciable fraction of the constituents of the germ1 and that it is almost1 if not wholly1 made up of assimilated and metamorphosed nutriment4 ,in the great majority of cases1 at any rate1 the full-grown organism becomes what it is by the absorption of not-living matter1 and its conversion into living matter of a specific type4 ,as ,harvey says 7,ex4 #de71 all parts of the body are nourished 8ab eodem succo alibili1 aliter aliterque cambiato10 8ut plant omnes ex eodem communi nutrimento 7sive rore seu terr humore740 ,in all animals and plants1 above the lowest1 the germ is a nucleated cell1 using that term in its broadest sense2 and the first step in the process of the evolution of the individual is the division of this cell into two or more portions4 ,the process of division is repeated1 until the organism1 from being unicellular1 becomes multicellular4 ,the single cell becomes a cell-aggregate2 and it is to the growth and metamorphosis of the cells of the cell-aggregate thus produced1 that all the organs and tissues of the adult owe their origin4 ,in certain animals belonging to every one of the chief groups into which the ,metazoa are divisible1 the cells of the cell-aggregate which results from the process of yelk-division1 and which is termed a morula1 diverge from one another in such a manner as to give rise to a central space1 around which they dispose themselves as a coat or envelope2 and thus the morula becomes a vesicle filled with fluid1 the planula4 ,the wall of the planula is next pushed in on one side1 or invaginated1 whereby it is converted into a double-walled sac with an opening1 the blastopore1 which leads into the cavity lined by the inner wall4 ,this cavity is the primitive alimentary cavity or archenteron2 the inner1 or invaginated1 layer is the hypoblast1 the outer the epiblast2 and the embryo1 in this stage1 is termed a gastrula4 ,in all the higher animals1 a layer of cells makes its appearance between the hypoblast and the epiblast1 and is termed the mesoblast4 ,in the further course of development1 the epiblast becomes the ectoderm or epidermic layer of the body2 the hypoblast becomes the epithelium of the middle portion of the alimentary canal2 and the mesoblast gives rise to all the other tissues1 except the central nervous system1 which originates from an ingrowth of the epiblast4 ,with more or less modification in detail1 the embryo has been observed to pass through these successive evolutional stages in sundry ,sponges1 ,clenterates1 ,worms1 ,echinoderms1 ,tunicates1 ,arthropods1 ,mollusks1 and ,vertebrates2 and there are valid reasons for the belief1 that all animals of higher organisation than the ,protozoa agree in the general character of the early stages of their individual evolution4 ,each1 starting from the condition of a simple nucleated cell1 becomes a cell-aggregate2 and this passes through a condition which represents the gastrula stage1 before taking on the features distinctive of the group to which it belongs4 ,stated in this form1 the 8gastra theory0 of ,haeckel appears to the present writer to be one of the most important and best founded of recent generalisations4 ,so far as individual plants and animals are concerned1 therefore1 evolution is not a speculation but a fact2 and it takes place by epigenesis4 8,animal 444 per epigenesin procreatur1 materiam simul attrahit1 parat1 concoquit1 et edem utitur2 formatur simul et augetur 444 primum futuri corporis concrementum 444 prout augetur1 dividitur sensim et distinguitur in partes1 non simul omnes1 sed alias post alias natas1 et ordine quasque suo emergentes40#gh ,in these words1 by the divination of genius1 ,harvey1 in the seventeenth century1 summed up the outcome of the work of all those who1 with appliances he could not dream of1 are continuing his labours in the nineteenth century4 ,nevertheless1 though the doctrine of epigenesis1 as understood by ,harvey1 has definitively triumphed over the doctrine of evolution1 as understood by his opponents of the eighteenth century1 it is not impossible that1 when the analysis of the process of development is carried still farther1 and the origin of the molecular components of the physically gross1 though sensibly minute1 bodies which we term germs is traced1 the theory of development will approach more nearly to metamorphosis than to epigenesis4 ,harvey thought that impregnation influenced the female organism as a contagion2 and that the blood1 which he conceived to be the first rudiment of the germ1 arose in the clear fluid of the 8colliquamentum0 of the ovum by a process of concrescence1 as a sort of living precipitate4 ,we now know1 on the contrary1 that the female germ or ovum1 in all the higher animals and plants1 is a body which possesses the structure of a nucleated cell2 that impregnation consists in the fusion of the substance#gi of another more or less modified nucleated cell1 the male germ1 with the ovum2 and that the structural components of the body of the embryo are all derived1 by a process of division1 from the coalesced male and female germs4 ,hence it is conceivable1 and indeed probable1 that every part of the adult contains molecules1 derived both from the male and from the female parent2 and that1 regarded as a mass of molecules1 the entire organism may be compared to a web of which the warp is derived from the female and the woof from the male4 ,and each of these may constitute one individuality1 in the same sense as the whole organism is one individual1 although the matter of the organism has been constantly changing4 ,the primitive male and female molecules may play the part of ,buffon's 8moules organiques10 and mould the assimilated nutriment1 each according to its own type1 into innumerable new molecules4 ,from this point of view the process1 which1 in its superficial aspect1 is epigenesis1 appears in essence1 to be evolution1 in the modified sense adopted in ,bonnet's later writings2 and development is merely the expansion of a potential organism or 8original preformation0 according to fixed laws4 ,,ii4 ,the ,evolution of the ,sum of ,living ,beings4 ,the notion that all the kinds of animals and plants may have come into existence by the growth and modification of primordial germs is as old as speculative thought2 but the modern scientific form of the doctrine can be traced historically to the influence of several converging lines of philosophical speculation and of physical observation1 none of which go farther back than the seventeenth century4 ,these are3-- #a4 ,the enunciation by ,descartes of the conception that the physical universe1 whether living or not living1 is a mechanism1 and that1 as such1 it is explicable on physical principles4 #b4 ,the observation of the gradations of structure1 from extreme simplicity to very great complexity1 presented by living things1 and of the relation of these graduated forms to one another4 #c4 ,the observation of the existence of an analogy between the series of gradations presented by the species which compose any great group of animals or plants1 and the series of embryonic conditions of the highest members of that group4 #d4 ,the observation that large groups of species of widely different habits present the same fundamental plan of structure2 and that parts of the same animal or plant1 the functions of which are very different1 likewise exhibit modifications of a common plan4 #e4 ,the observation of the existence of structures1 in a rudimentary and apparently useless condition1 in one species of a group1 which are fully developed and have definite functions in other species of the same group4 #f4 ,the observation of the effects of varying conditions in modifying living organisms4 #g4 ,the observation of the facts of geographical distribution4 #h4 ,the observation of the facts of the geological succession of the forms of life4 #a4 ,notwithstanding the elaborate disguise which fear of the powers that were led ,descartes to throw over his real opinions1 it is impossible to read the 8,principes de la ,philosophie0 without acquiring the conviction that this great philosopher held that the physical world and all things in it1 whether living or not living1 have originated by a process of evolution1 due to the continuous operation of purely physical causes1 out of a primitive relatively formless matter4#hj ,the following passage is especially instructive3-- 8,et tant s'en faut que je veuille que l'on croie toutes les choses que j'crirai1 que mme je pretends en proposer ici quelques unes que je crois absolument tre fausses2 savoir1 je ne doute point que le monde n'ait t cr au commencement avec autant de perfection qu'il en a2 en sorte que le soleil1 la terre1 la lune1 et les toiles ont t ds lors2 et que la terre n'a pas eu seulement en soi les semences des plantes1 mais que les plantes mme en ont couvert une partie2 et qu',adam et ,eve n'ont pas t crs enfans mais en ge d'hommes parfaits4 ,la religion chrtienne veut que nous le croyons ainsi1 et la raison naturelle nous persuade entirement cette vrit2 car si nous considrons la toute puissance de ,dieu1 nous devons juger que tout ce qu'il a fait a eu ds le commencement toute la perfection qu'il devoit avoir4 ,mais nanmoins1 comme on connitroit beaucoup mieux quelle a t la nature d',adam et celle des arbres de ,paradis si on avoit examin comment les enfants se forment peu peu dans le ventre de leurs mres et comment les plantes sortent de leurs semences1 que si on avoit seulement considr quels ils ont t quand ,dieu les a crs3 tout de mme1 nous ferons mieux entendre quelle est gnralement la nature de toutes les choses qui sont au monde si nous pouvons imaginer quelques principes qui soient fort intelligibles et fort simples1 desquels nous puissions voir clairement que les astres et la terre et enfin tout ce monde visible auroit pu tre produit ainsi que de quelques semences 7bien que nous sachions qu'il n'a pas t produit en cette faon7 que si nous la decrivions seulement comme il est1 ou bien comme nous croyons qu'il a t cr4 ,et parceque je pense avoir trouv des principes qui sont tels1 je tacherai ici de les expliquer40#ha ,if we read between the lines of this singular exhibition of force of one kind and weakness of another1 it is clear that ,descartes believed that he had divined the mode in which the physical universe had been evolved2 and the 8,trait de l'homme10 and the essay 8,sur les ,passions0 afford abundant additional evidence that he sought for1 and thought he had found1 an explanation of the phenomena of physical life by deduction from purely physical laws4 ,spinoza abounds in the same sense1 and is as usual perfectly candid-- 8,natur leges et regul1 secundum quas omnia fiunt et ex unis formis in alias mutantur1 sunt ubique et semper eadem40#hb ,leibnitz's doctrine of continuity necessarily led him in the same direction2 and1 of the infinite multitude of monads with which he peopled the world1 each is supposed to be the focus of an endless process of evolution and involution4 ,in the 8,protoga10 xxvi41 ,leibnitz distinctly suggests the mutability of species-- 8,alii mirantur in saxis passim species videri quas vel in orbe cognito1 vel saltem in vicinis locis frustra quras4 ,ita 8,cornua ,ammonis10 qu ex nautilorum numero habeantur1 passim et forma et magnitudine 7nam et pedali diametro aliquando reperiuntur7 ab omnibus illis naturis discrepare dicunt1 quas prbet mare4 ,sed quis absconditos ejus recessus aut subterraneas abyssos pervestigavit8 quam multa nobis animalia antea ignota offert novus orbis8 ,et credibile est per magnas illas conversiones etiam animalium species plurimum immutatas40 ,thus1 in the end of the seventeenth century1 the seed was sown which has1 at intervals1 brought forth recurrent crops of evolutional hypotheses1 based1 more or less completely1 on general reasonings4 ,among the earliest of these speculations is that put forward by ,benoit de ,maillet in his 8,telliamed10 which1 though printed in #agce1 was not published until twenty-three years later4 ,considering that this book was written before the time of ,haller1 or ,bonnet1 or ,linnus1 or ,hutton1 it surely deserves more respectful consideration than it usually receives4 ,for ,de ,maillet not only has a definite conception of the plasticity of living things1 and of the production of existing species by the modification of their predecessors2 but he clearly apprehends the cardinal maxim of modern geological science1 that the explanation of the structure of the globe is to be sought in the deductive application to geological phenomena of the principles established inductively by the study of the present course of nature4 ,somewhat later1 ,maupertuis#hc suggested a curious hypothesis as to the causes of variation1 which he thinks may be sufficient to account for the origin of all animals from a single pair4 ,robinet#hd followed out much the same line of thought as ,de ,maillet1 but less soberly2 and ,bonnet's speculations in the 8,palingnsie10 which appeared in #agfi1 have already been mentioned4 ,buffon 7#agec-aggh71 at first a partisan of the absolute immutability of species1 subsequently appears to have believed that larger or smaller groups of species have been produced by the modification of a primitive stock2 but he contributed nothing to the general doctrine of evolution4 ,erasmus ,darwin 78,zoonomia10 #agid71 though a zealous evolutionist1 can hardly be said to have made any real advance on his predecessors2 and1 notwithstanding that ,goethe 7#agia-d7 had the advantage of a wide knowledge of morphological facts1 and a true insight into their signification1 while he threw all the power of a great poet into the expression of his conceptions1 it may be questioned whether he supplied the doctrine of evolution with a firmer scientific basis than it already possessed4 ,moreover1 whatever the value of ,goethe's labours in that field1 they were not published before #ahbj1 long after evolutionism had taken a new departure from the works of ,treviranus and ,lamarck--the first of its advocates who were equipped for their task with the needful large and accurate knowledge of the phenomena of life1 as a whole4 ,it is remarkable that each of these writers seems to have been led1 independently and contemporaneously1 to invent the same name of 8,biology0 for the science of the phenomena of life2 and thus1 following ,buffon1 to have recognised the essential unity of these phenomena1 and their contradistinction from those of inanimate nature4 ,and it is hard to say whether ,lamarck or ,treviranus has the priority in propounding the main thesis of the doctrine of evolution2 for though the first volume of ,treviranus's 8,biologie0 appeared only in #ahjb1 he says1 in the preface to his later work1 the 8,erscheinungen und ,gesetze des organischen ,lebens10 dated #ahca1 that he wrote the first volume of the 8,biologie0 8nearly five-and-thirty years ago10 or about #agif4 ,now1 in #agid1 there is evidence that ,lamarck held doctrines which present a striking contrast to those which are to be found in the 8,philosophic ,zoologique10 as the following passages show3-- 8#fhe4 ,quoique mon unique objet dans cet article n'ait t que de traiter de la cause physique de l'entretien de la vie des tres organiques1 malgr cela j'ai os avancer en dbutant1 que l'existence de ces tres tonnants n'appartiennent nullement la nature2 que tout ce qu'on peut entendre par le mot nature1 ne pouvoit donner la vie1 c'est--dire1 que toutes les qualits de la matire1 jointes toutes les circonstances possibles1 et mme l'activit rpandue dans l'univers1 ne pouvaient point produire un tre muni du mouvement organique1 capable de reproduire son semblable1 et sujet la mort4 8#fhf4 ,tous les individus de cette nature1 qui existent1 proviennent d'individus semblables qui tous ensemble constituent l'espce entire4 ,or1 je crois qu'il est aussi impossible l'homme de connitre la cause physique du premier individu de chaque espce1 que d'assigner aussi physiquement la cause de l'existence de la matire ou de l'univers entier4 ,c'est au moins ce que le rsultat de mes connaissances et de mes rflexions me portent penser4 ,s'il existe beaucoup de varits produites par l'effet des circonstances1 ces varits ne dnaturent point les espces2 mais on se trompe1 sans doute souvent1 en indiquant comme espce1 ce qui n'est que varit2 et alors je sens que cette erreur peut tirer consquence dans les raisonnements que l'on fait sur cette matire40#he ,the first three volumes of ,treviranus's 8,biologie10 which contain his general views of evolution1 appeared between #ahjb and #ahje4 ,the 8,recherches sur l'organisation des corps vivants10 in which the outlines of ,lamarck's doctrines are given1 was published in #ahjb2 but the full development of his views1 in the 8,philosophie ,zoologique10 did not take place until #ahji4 ,the 8,biologie0 and the 8,philosophie ,zoologique0 are both very remarkable productions1 and are still worthy of attentive study1 but they fell upon evil times4 ,the vast authority of ,cuvier was employed in support of the traditionally respectable hypotheses of special creation and of catastrophism2 and the wild speculations of the 8,discours sur les ,rvolutions de la ,surface du ,globe0 were held to be models of sound scientific thinking1 while the really much more sober and philosophical hypotheses of the 8,hydrogeologie0 were scouted4 ,for many years it was the fashion to speak of ,lamarck with ridicule1 while ,treviranus was altogether ignored4 ,nevertheless1 the work had been done4 ,the conception of evolution was henceforward irrepressible1 and it incessantly reappears1 in one shape or another1#hf up to the year #aheh1 when ,mr4 ,darwin and ,mr4 ,wallace published their 8,theory of ,natural ,selection40 ,the 8,origin of ,species0 appeared in #ahei2 and it is within the knowledge of all whose memories go back to that time1 that1 henceforward1 the doctrine of evolution has assumed a position and acquired an importance which it never before possessed4 ,in the 8,origin of ,species10 and in his other numerous and important contributions to the solution of the problem of biological evolution1 ,mr4 ,darwin confines himself to the discussion of the causes which have brought about the present condition of living matter1 assuming such matter to have once come into existence4 ,on the other hand1 ,mr4 ,spencer#hg and ,professor ,haeckel#hh have dealt with the whole problem of evolution4 ,the profound and vigorous writings of ,mr4 ,spencer embody the spirit of ,descartes in the knowledge of our own day1 and may be regarded as the 8,principes de la ,philosophie0 of the nineteenth century2 while1 whatever hesitation may not unfrequently be felt by less daring minds1 in following ,haeckel in many of his speculations1 his attempt to systematise the doctrine of evolution and to exhibit its influence as the central thought of modern biology1 cannot fail to have a far-reaching influence on the progress of science4 ,if we seek for the reason of the difference between the scientific position of the doctrine of evolution a century ago1 and that which it occupies now1 we shall find it in the great accumulation of facts1 the several classes of which have been enumerated above1 under the second to the eighth heads4 ,for those which are grouped under the second to the seventh of these classes1 respectively1 have a clear significance on the hypothesis of evolution1 while they are unintelligible if that hypothesis be denied4 ,and those of the eighth group are not only unintelligible without the assumption of evolution1 but can be proved never to be discordant with that hypothesis1 while1 in some cases1 they are exactly such as the hypothesis requires4 ,the demonstration of these assertions would require a volume1 but the general nature of the evidence on which they rest may be briefly indicated4 #b4 ,the accurate investigation of the lowest forms of animal life1 commenced by ,leeuwenhoek and ,swammerdam1 and continued by the remarkable labours of ,reaumur1 ,trembley1 ,bonnet1 and a host of other observers1 in the latter part of the seventeenth and the first half of the eighteenth centuries1 drew the attention of biologists to the gradation in the complexity of organisation which is presented by living beings1 and culminated in the doctrine of the 8chelle des tres10 so powerfully and clearly stated by ,bonnet2 and1 before him1 adumbrated by ,locke and by ,leibnitz4 ,in the then state of knowledge1 it appeared that all the species of animals and plants could be arranged in one series2 in such a manner that1 by insensible gradations1 the mineral passed into the plant1 the plant into the polype1 the polype into the worm1 and so1 through gradually higher forms of life1 to man1 at the summit of the animated world4 ,but1 as knowledge advanced1 this conception ceased to be tenable in the crude form in which it was first put forward4 ,taking into account existing animals and plants alone1 it became obvious that they fell into groups which were more or less sharply separated from one another2 and1 moreover1 that even the species of a genus can hardly ever be arranged in linear series4 ,their natural resemblances and differences are only to be expressed by disposing them as if they were branches springing from a common hypothetical centre4 ,lamarck1 while affirming the verbal proposition that animals form a single series1 was forced by his vast acquaintance with the details of zoology to limit the assertion to such a series as may be formed out of the abstractions constituted by the common characters of each group4#hi ,cuvier on anatomical1 and ,von ,baer on embryological grounds1 made the further step of proving that1 even in this limited sense1 animals cannot be arranged in a single series1 but that there are several distinct plans of organisation to be observed among them1 no one of which1 in its highest and most complicated modification1 leads to any of the others4 ,the conclusions enunciated by ,cuvier and ,von ,baer have been confirmed1 in principle1 by all subsequent research into the structure of animals and plants4 ,but the effect of the adoption of these conclusions has been rather to substitute a new metaphor for that of ,bonnet than to abolish the conception expressed by it4 ,instead of regarding living things as capable of arrangement in one series like the steps of a ladder1 the results of modern investigation compel us to dispose them as if they were the twigs and branches of a tree4 ,the ends of the twigs represent individuals1 the smallest groups of twigs species1 larger groups genera1 and so on1 until we arrive at the source of all these ramifications of the main branch1 which is represented by a common plan of structure4 ,at the present moment1 it is impossible to draw up any definition1 based on broad anatomical or developmental characters1 by which any one of ,cuvier's great groups shall be separated from all the rest4 ,on the contrary1 the lower members of each tend to converge towards the lower members of all the others4 ,the same may be said of the vegetable world4 ,the apparently clear distinction between flowering and flowerless plants has been broken down by the series of gradations between the two exhibited by the ,lycopodiace1 ,rhizocarpe1 and ,gymnosperme4 ,the groups of ,fungi1 ,lichenes1 and ,alg have completely run into one another1 and1 when the lowest forms of each are alone considered1 even the animal and vegetable kingdoms cease to have a definite frontier4 ,if it is permissible to speak of the relations of living forms to one another metaphorically1 the similitude chosen must undoubtedly be that of a common root1 whence two main trunks1 one representing the vegetable and one the animal world1 spring2 and1 each dividing into a few main branches1 these subdivide into multitudes of branchlets and these into smaller groups of twigs4 ,as ,lamarck has well said--#ij 8,il n'y a que ceux qui se sont longtemps et fortement occups de la dtermination des espces1 et qui ont consult de riches collections1 qui peuvent savoir jusqu' quel point les espces1 parmi les corps vivants se fondent les unes dans les autres1 et qui ont pu se convaincre que1 dans les parties o nous voyons des espces isols1 cela n'est ainsi que parcequ'il nous en manque d'autres qui en sont plus voisines et que nous n'avons pas encore recueillies4 8,je ne veux pas dire pour cela que les animaux qui existent forment une srie trs-simple et partout galement nuance2 mais je dis qu'ils forment une srie rameuse1 irrgulirement gradue et qui n'a point de discontinuit dans ses parties1 ou qui1 du moins1 n'en a toujours pas eu1 s'il est vrai que1 par suite de quelques espces perdues1 il s'en trouve quelque part4 ,il en resulte que les espces qui terminent chaque rameau de la srie gnrale tiennent1 au moins d'un ct1 d'autres espces voisines qui se nuancent avec elles4 ,voil ce que l'tat bien connu des choses me met maintenant porte de demontrer4 ,je n'ai besoin d'aucune hypothse ni d'aucune supposition pour cela3 j'en atteste tous les naturalistes observateurs40 #c4 ,in a remarkable essay#ia ,meckel remarks-- 8,there is no good physiologist who has not been struck by the observation that the original form of all organisms is one and the same1 and that out of this one form1 all1 the lowest as well as the highest1 are developed in such a manner that the latter pass through the permanent forms of the former as transitory stages4 ,aristotle1 ,haller1 ,harvey1 ,kielmeyer1 ,autenrieth1 and many others1 have either made this observation incidentally1 or1 especially the latter1 have drawn particular attention to it1 and drawn therefrom results of permanent importance for physiology40 ,meckel proceeds to exemplify the thesis1 that the lower forms of animals represent stages in the course of the development of the higher1 with a large series of illustrations4 ,after comparing the ,salamanders and the perenni-branchiate ,urodela with the ,tadpoles and the ,frogs1 and enunciating the law that the more highly any animal is organised the more quickly does it pass through the lower stages1 ,meckel goes on to say-- 8,from these lowest ,vertebrata to the highest1 and to the highest forms among these1 the comparison between the embryonic conditions of the higher animals and the adult states of the lower can be more completely and thoroughly instituted than if the survey is extended to the ,invertebrata1 inasmuch as the latter are in many respects constructed upon an altogether too dissimilar type2 indeed they often differ from one another far more than the lowest vertebrate does from the highest mammal2 yet the following pages will show that the comparison may also be extended to them with interest4 ,in fact1 there is a period when1 as ,aristotle long ago said1 the embryo of the highest animal has the form of a mere worm2 and1 devoid of internal and external organisation1 is merely an almost structureless lump of polype-substance4 ,notwithstanding the origin of organs1 it still for a certain time1 by reason of its want of an internal bony skeleton1 remains worm and mollusk1 and only later enters into the series of the ,vertebrata1 although traces of the vertebral column even in the earliest periods testify its claim to a place in that series40--,op4 cit4 pp4 #d1 #e4 ,if ,meckel's proposition is so far qualified1 that the comparison of adult with embryonic forms is restricted within the limits of one type of organisation2 and1 if it is further recollected that the resemblance between the permanent lower form and the embryonic stage of a higher form is not special but general1 it is in entire accordance with modern embryology2 although there is no branch of biology which has grown so largely1 and improved its methods so much1 since ,meckel's time1 as this4 ,in its original form1 the doctrine of 8arrest of development10 as advocated by ,geoffroy ,saint-,hilaire and ,serres1 was no doubt an over-statement of the case4 ,it is not true1 for example1 that a fish is a reptile arrested in its development1 or that a reptile was ever a fish3 but it is true that the reptile embryo1 at one stage of its development1 is an organism which1 if it had an independent existence1 must be classified among fishes2 and all the organs of the reptile pass1 in the course of their development1 through conditions which are closely analogous to those which are permanent in some fishes4 #d4 ,that branch of biology which is termed ,morphology is a commentary upon1 and expansion of1 the proposition that widely different animals or plants1 and widely different parts of animals or plants1 are constructed upon the same plan4 ,from the rough comparison of the skeleton of a bird with that of a man by ,belon1 in the sixteenth century 7to go no farther back71 down to the theory of the limbs and the theory of the skull at the present day2 or1 from the first demonstration of the homologies of the parts of a flower by ,c4 ,f4 ,wolff1 to the present elaborate analysis of the floral organs1 morphology exhibits a continual advance towards the demonstration of a fundamental unity among the seeming diversities of living structures4 ,and this demonstration has been completed by the final establishment of the cell theory1 which involves the admission of a primitive conformity1 not only of all the elementary structures in animals and plants respectively1 but of those in the one of these great divisions of living things with those in the other4 ,no priori difficulty can be said to stand in the way of evolution1 when it can be shown that all animals and all plants proceed by modes of development1 which are similar in principle1 from a fundamental protoplasmic material4 #e4 ,the innumerable cases of structures1 which are rudimentary and apparently useless1 in species1 the close allies of which possess well developed and functionally important homologous structures1 are readily intelligible on the theory of evolution1 while it is hard to conceive their raison d'tre on any other hypothesis4 ,however1 a cautious reasoner will probably rather explain such cases deductively from the doctrine of evolution than endeavour to support the doctrine of evolution by them4 ,for it is almost impossible to prove that any structure1 however rudimentary1 is useless--that is to say1 that it plays no part whatever in the economy2 and1 if it is in the slightest degree useful1 there is no reason why1 on the hypothesis of direct creation1 it should not have been created4 ,nevertheless1 double-edged as is the argument from rudimentary organs1 there is probably none which has produced a greater effect in promoting the general acceptance of the theory of evolution4 #f4 ,the older advocates of evolution sought for the causes of the process exclusively in the influence of varying conditions1 such as climate and station1 or hybridisation1 upon living forms4 ,even ,treviranus has got no farther than this point4 ,lamarck introduced the conception of the action of an animal on itself as a factor in producing modification4 ,starting from the well-known fact that the habitual use of a limb tends to develop the muscles of the limb1 and to produce a greater and greater facility in using it1 he made the general assumption that the effort of an animal to exert an organ in a given direction tends to develop the organ in that direction4 ,but a little consideration showed that1 though ,lamarck had seized what1 as far as it goes1 is a true cause of modification1 it is a cause the actual effects of which are wholly inadequate to account for any considerable modification in animals1 and which can have no influence at all in the vegetable world2 and probably nothing contributed so much to discredit evolution1 in the early part of this century1 as the floods of easy ridicule which were poured upon this part of ,lamarck's speculation4 ,the theory of natural selection1 or survival of the fittest1 was suggested by ,wells in #ahac1 and further elaborated by ,matthew in #ahca4 ,but the pregnant suggestions of these writers remained practically unnoticed and forgotten1 until the theory was independently devised and promulgated by ,darwin and ,wallace in #aheh1 and the effect of its publication was immediate and profound4 ,those who were unwilling to accept evolution1 without better grounds than such as are offered by ,lamarck1 or the author of that particularly unsatisfactory book1 the 8,vestiges of the ,natural ,history of the ,creation10 and who therefore preferred to suspend their judgment on the question1 found1 in the principle of selective breeding1 pursued in all its applications with marvellous knowledge and skill by ,mr4 ,darwin1 a valid explanation of the occurrence of varieties and races2 and they saw clearly that1 if the explanation would apply to species1 it would not only solve the problem of their evolution1 but that it would account for the facts of teleology1 as well as for those of morphology2 and for the persistence of some forms of life unchanged through long epochs of time1 while others undergo comparatively rapid metamorphosis4 ,how far 8natural selection0 suffices for the production of species remains to be seen4 ,few can doubt that1 if not the whole cause1 it is a very important factor in that operation2 and that it must play a great part in the sorting out of varieties into those which are transitory and those which are permanent4 ,but the causes and conditions of variation have yet to be thoroughly explored2 and the importance of natural selection will not be impaired1 even if further inquiries should prove that variability is definite1 and is determined in certain directions rather than in others1 by conditions inherent in that which varies4 ,it is quite conceivable that every species tends to produce varieties of a limited number and kind1 and that the effect of natural selection is to favour the development of some of these1 while it opposes the development of others along their predetermined lines of modification4 #g4 ,no truths brought to light by biological investigation were better calculated to inspire distrust of the dogmas intruded upon science in the name of theology1 than those which relate to the distribution of animals and plants on the surface of the earth4 ,very skilful accommodation was needful1 if the limitation of sloths to ,south ,america1 and of the ornithorhynchus to ,australia1 was to be reconciled with the literal interpretation of the history of the deluge2 and1 with the establishment of the existence of distinct provinces of distribution1 any serious belief in the peopling of the world by migration from ,mount ,ararat came to an end4 ,under these circumstances1 only one alternative was left for those who denied the occurrence of evolution--namely1 the supposition that the characteristic animals and plants of each great province were created1 as such1 within the limits in which we find them4 ,and as the hypothesis of 8specific centres10 thus formulated1 was heterodox from the theological point of view1 and unintelligible under its scientific aspect1 it may be passed over without further notice1 as a phase of transition from the creational to the evolutional hypothesis4 #h4 ,in fact1 the strongest and most conclusive arguments in favour of evolution are those which are based upon the facts of geographical1 taken in conjunction with those of geological1 distribution4 ,both ,mr4 ,darwin and ,mr4 ,wallace lay great stress on the close relation which obtains between the existing fauna of any region and that of the immediately antecedent geological epoch in the same region2 and rightly1 for it is in truth inconceivable that there should be no genetic connection between the two4 ,it is possible to put into words the proposition that all the animals and plants of each geological epoch were annihilated1 and that a new set of very similar forms was created for the next epoch2 but it may be doubted if any one who ever tried to form a distinct mental image of this process of spontaneous generation on the grandest scale1 ever really succeeded in realising it4 ,within the last twenty years1 the attention of the best palontologists has been withdrawn from the hodman's work of making 8new species0 of fossils1 to the scientific task of completing our knowledge of individual species1 and tracing out the succession of the forms presented by any given type in time4 ,those who desire to inform themselves of the nature and extent of the evidence bearing on these questions may consult the works of ,rtimeyer1 ,gaudry1 ,kowalewsky1 ,marsh1 and the writer of the present article4 ,it must suffice1 in this place1 to say that the successive forms of the ,equine type have been fully worked out2 while those of nearly all the other existing types of ,ungulate mammals and of the ,carnivora have been almost as closely followed through the ,tertiary deposits2 the gradations between birds and reptiles have been traced2 and the modifications undergone by the ,crocodilia1 from the ,triassic epoch to the present day1 have been demonstrated4 ,on the evidence of palontology1 the evolution of many existing forms of animal life from their predecessors is no longer an hypothesis1 but an historical fact2 it is only the nature of the physiological factors to which that evolution is due which is still open to discussion4 ,,xii4 ,,the ,,coming ,,of ,,age ,,of 8,,the ,,origin ,,of ,,species40 ,many of you will be familiar with the aspect of this small green-covered book4 ,it is a copy of the first edition of the 8,origin of ,species10 and bears the date of its production--the #ast of ,october #ahei4 ,only a few months1 therefore1 are needed to complete the full tale of twenty-one years since its birthday4 ,those whose memories carry them back to this time will remember that the infant was remarkably lively1 and that a great number of excellent persons mistook its manifestations of a vigorous individuality for mere naughtiness2 in fact there was a very pretty turmoil about its cradle4 ,my recollections of the period are particularly vivid2 for1 having conceived a tender affection for a child of what appeared to me to be such remarkable promise1 ,i acted for some time in the capacity of a sort of under-nurse1 and thus came in for my share of the storms which threatened the very life of the young creature4 ,for some years it was undoubtedly warm work2 but considering how exceedingly unpleasant the apparition of the new-comer must have been to those who did not fall in love with him at first sight1 ,i think it is to the credit of our age that the war was not fiercer1 and that the more bitter and unscrupulous forms of opposition died away as soon as they did4 ,i speak of this period as of something past and gone1 possessing merely an historical1 ,i had almost said an antiquarian interest4 ,for1 during the second decade of the existence of the 8,origin of ,species10 opposition1 though by no means dead1 assumed a different aspect4 ,on the part of all those who had any reason to respect themselves1 it assumed a thoroughly respectful character4 ,by this time1 the dullest began to perceive that the child was not likely to perish of any congenital weakness or infantile disorder1 but was growing into a stalwart personage1 upon whom mere goody scoldings and threatenings with the birch-rod were quite thrown away4 ,in fact1 those who have watched the progress of science within the last ten years will bear me out to the full1 when ,i assert that there is no field of biological inquiry in which the influence of the 8,origin of ,species0 is not traceable2 the foremost men of science in every country are either avowed champions of its leading doctrines1 or at any rate abstain from opposing them2 a host of young and ardent investigators seek for and find inspiration and guidance in ,mr4 ,darwin's great work2 and the general doctrine of evolution1 to one side of which it gives expression1 obtains1 in the phenomena of biology1 a firm base of operations whence it may conduct its conquest of the whole realm of nature4 ,history warns us1 however1 that it is the customary fate of new truths to begin as heresies and to end as superstitions2 and1 as matters now stand1 it is hardly rash to anticipate that1 in another twenty years1 the new generation1 educated under the influences of the present day1 will be in danger of accepting the main doctrines of the 8,origin of ,species10 with as little reflection1 and it may be with as little justification1 as so many of our contemporaries1 twenty years ago1 rejected them4 ,against any such a consummation let us all devoutly pray2 for the scientific spirit is of more value than its products1 and irrationally held truths may be more harmful than reasoned errors4 ,now the essence of the scientific spirit is criticism4 ,it tells us that whenever a doctrine claims our assent we should reply1 ,take it if you can compel it4 ,the struggle for existence holds as much in the intellectual as in the physical world4 ,a theory is a species of thinking1 and its right to exist is coextensive with its power of resisting extinction by its rivals4 ,from this point of view1 it appears to me that it would be but a poor way of celebrating the ,coming of ,age of the 8,origin of ,species10 were ,i merely to dwell upon the facts1 undoubted and remarkable as they are1 of its far-reaching influence and of the great following of ardent disciples who are occupied in spreading and developing its doctrines4 ,mere insanities and inanities have before now swollen to portentous size in the course of twenty years4 ,let us rather ask this prodigious change in opinion to justify itself2 let us inquire whether anything has happened since #ahei1 which will explain1 on rational grounds1 why so many are worshipping that which they burned1 and burning that which they worshipped4 ,it is only in this way that we shall acquire the means of judging whether the movement we have witnessed is a mere eddy of fashion1 or truly one with the irreversible current of intellectual progress1 and1 like it1 safe from retrogressive reaction4 ,every belief is the product of two factors3 the first is the state of the mind to which the evidence in favour of that belief is presented2 and the second is the logical cogency of the evidence itself4 ,in both these respects1 the history of biological science during the last twenty years appears to me to afford an ample explanation of the change which has taken place2 and a brief consideration of the salient events of that history will enable us to understand why1 if the 8,origin of ,species0 appeared now1 it would meet with a very different reception from that which greeted it in #ahei4 ,one-and-twenty years ago1 in spite of the work commenced by ,hutton and continued with rare skill and patience by ,lyell1 the dominant view of the past history of the earth was catastrophic4 ,great and sudden physical revolutions1 wholesale creations and extinctions of living beings1 were the ordinary machinery of the geological epic brought into fashion by the misapplied genius of ,cuvier4 ,it was gravely maintained and taught that the end of every geological epoch was signalised by a cataclysm1 by which every living being on the globe was swept away1 to be replaced by a brand-new creation when the world returned to quiescence4 ,a scheme of nature which appeared to be modelled on the likeness of a succession of rubbers of whist1 at the end of each of which the players upset the table and called for a new pack1 did not seem to shock anybody4 ,i may be wrong1 but ,i doubt if1 at the present time1 there is a single responsible representative of these opinions left4 ,the progress of scientific geology has elevated the fundamental principle of uniformitarianism1 that the explanation of the past is to be sought in the study of the present1 into the position of an axiom2 and the wild speculations of the catastrophists1 to which we all listened with respect a quarter of a century ago1 would hardly find a single patient hearer at the present day4 ,no physical geologist now dreams of seeking1 outside the range of known natural causes1 for the explanation of anything that happened millions of years ago1 any more than he would be guilty of the like absurdity in regard to current events4 ,the effect of this change of opinion upon biological speculation is obvious4 ,for1 if there have been no periodical general physical catastrophes1 what brought about the assumed general extinctions and re-creations of life which are the corresponding biological catastrophes8 ,and1 if no such interruptions of the ordinary course of nature have taken place in the organic1 any more than in the inorganic1 world1 what alternative is there to the admission of evolution8 ,the doctrine of evolution in biology is the necessary result of the logical application of the principles of uniformitarianism to the phenomena of life4 ,darwin is the natural successor of ,hutton and ,lyell1 and the 8,origin of ,species0 the logical sequence of the 8,principles of ,geology40 ,the fundamental doctrine of the 8,origin of ,species10 as of all forms of the theory of evolution applied to biology1 is 8that the innumerable species1 genera1 and families of organic beings with which the world is peopled have all descended1 each within its own class or group1 from common parents1 and have all been modified in the course of descent40#ib ,and1 in view of the facts of geology1 it follows that all living animals and plants 8are the lineal descendants of those which lived long before the ,silurian epoch40#ic ,it is an obvious consequence of this theory of descent with modification1 as it is sometimes called1 that all plants and animals1 however different they may now be1 must1 at one time or other1 have been connected by direct or indirect intermediate gradations1 and that the appearance of isolation presented by various groups of organic beings must be unreal4 ,no part of ,mr4 ,darwin's work ran more directly counter to the prepossessions of naturalists twenty years ago than this4 ,and such prepossessions were very excusable1 for there was undoubtedly a great deal to be said1 at that time1 in favour of the fixity of species and of the existence of great breaks1 which there was no obvious or probable means of filling up1 between various groups of organic beings4 ,for various reasons1 scientific and unscientific1 much had been made of the hiatus between man and the rest of the higher mammalia1 and it is no wonder that issue was first joined on this part of the controversy4 ,i have no wish to revive past and happily forgotten controversies2 but ,i must state the simple fact that the distinctions in the cerebral and other characters1 which were so hotly affirmed to separate man from all other animals in #ahfj1 have all been demonstrated to be non-existent1 and that the contrary doctrine is now universally accepted and taught4 ,but there were other cases in which the wide structural gaps asserted to exist between one group of animals and another1 were by no means fictitious2 and1 when such structural breaks were real1 ,mr4 ,darwin could account for them only by supposing that the intermediate forms which once existed had become extinct4 ,in a remarkable passage he says-- 8,we may thus account even for the distinctness of whole classes from each other--for instance1 of birds from all other vertebrate animals--by the belief that many animal forms of life have been utterly lost1 through which the early progenitors of birds were formerly connected with the early progenitors of the other vertebrate classes40#id ,adverse criticism made merry over such suggestions as these4 ,of course it was easy to get out of the difficulty by supposing extinction2 but where was the slightest evidence that such intermediate forms between birds and reptiles as the hypothesis required ever existed8 ,and then probably followed a tirade upon this terrible forsaking of the paths of 8,baconian induction40 ,but the progress of knowledge has justified ,mr4 ,darwin to an extent which could hardly have been anticipated4 ,in #ahfb1 the specimen of ,archopteryx1 which1 until the last two or three years1 has remained unique1 was discovered2 and it is an animal which1 in its feathers and the greater part of its organisation1 is a veritable bird1 while1 in other parts1 it is as distinctly reptilian4 ,in #ahfh1 ,i had the honour of bringing under your notice1 in this theatre1 the results of investigations made1 up to that time1 into the anatomical characters of certain ancient reptiles1 which showed the nature of the modifications in virtue of which the type of the quadrupedal reptile passed into that of a bipedal bird2 and abundant confirmatory evidence of the justice of the conclusions which ,i then laid before you has since come to light4 ,in #ahge1 the discovery of the toothed birds of the cretaceous formation in ,north ,america by ,professor ,marsh completed the series of transitional forms between birds and reptiles1 and removed ,mr4 ,darwin's proposition that 8many animal forms of life have been utterly lost1 through which the early progenitors of birds were formerly connected with the early progenitors of the other vertebrate classes10 from the region of hypothesis to that of demonstrable fact4 ,in #ahei1 there appeared to be a very sharp and clear hiatus between vertebrated and invertebrated animals1 not only in their structure1 but1 what was more important1 in their development4 ,i do not think that we even yet know the precise links of connection between the two2 but the investigations of ,kowalewsky and others upon the development of ,amphioxus and of the ,tunicata prove1 beyond a doubt1 that the differences which were supposed to constitute a barrier between the two are non-existent4 ,there is no longer any difficulty in understanding how the vertebrate type may have arisen from the invertebrate1 though the full proof of the manner in which the transition was actually effected may still be lacking4 ,again1 in #ahei1 there appeared to be a no less sharp separation between the two great groups of flowering and flowerless plants4 ,it is only subsequently that the series of remarkable investigations inaugurated by ,hofmeister has brought to light the extraordinary and altogether unexpected modifications of the reproductive apparatus in the ,lycopodiace1 the ,rhizocarpe1 and the ,gymnosperme1 by which the ferns and the mosses are gradually connected with the ,phanerogamic division of the vegetable world4 ,so1 again1 it is only since #ahei that we have acquired that wealth of knowledge of the lowest forms of life which demonstrates the futility of any attempt to separate the lowest plants from the lowest animals1 and shows that the two kingdoms of living nature have a common borderland which belongs to both or to neither4 ,thus it will be observed that the whole tendency of biological investigation1 since #ahei1 has been in the direction of removing the difficulties which the apparent breaks in the series created at that time2 and the recognition of gradation is the first step towards the acceptance of evolution4 ,as another great factor in bringing about the change of opinion which has taken place among naturalists1 ,i count the astonishing progress which has been made in the study of embryology4 ,twenty years ago1 not only were we devoid of any accurate knowledge of the mode of development of many groups of animals and plants1 but the methods of investigation were rude and imperfect4 ,at the present time1 there is no important group of organic beings the development of which has not been carefully studied2 and the modern methods of hardening and section-making enable the embryologist to determine the nature of the process1 in each case1 with a degree of minuteness and accuracy which is truly astonishing to those whose memories carry them back to the beginnings of modern histology4 ,and the results of these embryological investigations are in complete harmony with the requirements of the doctrine of evolution4 ,the first beginnings of all the higher forms of animal life are similar1 and however diverse their adult conditions1 they start from a common foundation4 ,moreover1 the process of development of the animal or the plant from its primary egg or germ is a true process of evolution--a progress from almost formless to more or less highly organised matter1 in virtue of the properties inherent in that matter4 ,to those who are familiar with the process of development1 all priori objections to the doctrine of biological evolution appear childish4 ,any one who has watched the gradual formation of a complicated animal from the protoplasmic mass1 which constitutes the essential element of a frog's or a hen's egg1 has had under his eyes sufficient evidence that a similar evolution of the whole animal world from the like foundation is1 at any rate1 possible4 ,yet another product of investigation has largely contributed to the removal of the objections to the doctrine of evolution current in #ahei4 ,it is the proof afforded by successive discoveries that ,mr4 ,darwin did not over-estimate the imperfection of the geological record4 ,no more striking illustration of this is needed than a comparison of our knowledge of the mammalian fauna of the ,tertiary epoch in #ahei with its present condition4 ,m4 ,gaudry's researches on the fossils of ,pikermi were published in #ahfh1 those of ,messrs4 ,leidy1 ,marsh1 and ,cope1 on the fossils of the ,western ,territories of ,america1 have appeared almost wholly since #ahgj1 those of ,m4 ,filhol on the phosphorites of ,quercy in #ahgh4 ,the general effect of these investigations has been to introduce to us a multitude of extinct animals1 the existence of which was previously hardly suspected2 just as if zoologists were to become acquainted with a country1 hitherto unknown1 as rich in novel forms of life as ,brazil or ,south ,africa once were to ,europeans4 ,indeed1 the fossil fauna of the ,western ,territories of ,america bids fair to exceed in interest and importance all other known ,tertiary deposits put together2 and yet1 with the exception of the case of the ,american tertiaries1 these investigations have extended over very limited areas2 and1 at ,pikermi1 were confined to an extremely small space4 ,such appear to me to be the chief events in the history of the progress of knowledge during the last twenty years1 which account for the changed feeling with which the doctrine of evolution is at present regarded by those who have followed the advance of biological science1 in respect of those problems which bear indirectly upon that doctrine4 ,but all this remains mere secondary evidence4 ,it may remove dissent1 but it does not compel assent4 ,primary and direct evidence in favour of evolution can be furnished only by palontology4 ,the geological record1 so soon as it approaches completeness1 must1 when properly questioned1 yield either an affirmative or a negative answer3 if evolution has taken place1 there will its mark be left2 if it has not taken place1 there will lie its refutation4 ,what was the state of matters in #ahei8 ,let us hear ,mr4 ,darwin1 who may be trusted always to state the case against himself as strongly as possible4 8,on this doctrine of the extermination of an infinitude of connecting links between the living and extinct inhabitants of the world1 and at each successive period between the extinct and still older species1 why is not every geological formation charged with such links8 ,why does not every collection of fossil remains afford plain evidence of the gradation and mutation of the forms of life8 ,we meet with no such evidence1 and this is the most obvious and plausible of the many objections which may be urged against my theory40#ie ,nothing could have been more useful to the opposition than this characteristically candid avowal1 twisted as it immediately was into an admission that the writer's views were contradicted by the facts of palontology4 ,but1 in fact1 ,mr4 ,darwin made no such admission4 ,what he says in effect is1 not that palontological evidence is against him1 but that it is not distinctly in his favour2 and1 without attempting to attenuate the fact1 he accounts for it by the scantiness and the imperfection of that evidence4 ,what is the state of the case now1 when1 as we have seen1 the amount of our knowledge respecting the mammalia of the ,tertiary epoch is increased fifty-fold1 and in some directions even approaches completeness8 ,simply this1 that1 if the doctrine of evolution had not existed1 palontologists must have invented it1 so irresistibly is it forced upon the mind by the study of the remains of the ,tertiary mammalia which have been brought to light since #ahei4 ,among the fossils of ,pikermi1 ,gaudry found the successive stages by which the ancient civets passed into the more modern hynas2 through the ,tertiary deposits of ,western ,america1 ,marsh tracked the successive forms by which the ancient stock of the horse has passed into its present form2 and innumerable less complete indications of the mode of evolution of other groups of the higher mammalia have been obtained4 ,in the remarkable memoir on the phosphorites of ,quercy1 to which ,i have referred1 ,m4 ,filhol describes no fewer than seventeen varieties of the genus ,cynodictis1 which fill up all the interval between the viverine animals and the bear-like dog ,amphicyon2 nor do ,i know any solid ground of objection to the supposition that1 in this ,cynodictis-,amphicyon group1 we have the stock whence all the ,viverid1 ,felid1 ,hynid1 ,canid1 and perhaps the ,procyonid and ,ursid1 of the present fauna have been evolved4 ,on the contrary1 there is a great deal to be said in favour4 ,in the course of summing up his results1 ,m4 ,filhol observes3-- 8,during the epoch of the phosphorites1 great changes took place in animal forms1 and almost the same types as those which now exist became defined from one another4 8,under the influence of natural conditions of which we have no exact knowledge1 though traces of them are discoverable1 species have been modified in a thousand ways3 races have arisen which1 becoming fixed1 have thus produced a corresponding number of secondary species40 ,in #ahei1 language of which this is an unintentional paraphrase1 occurring in the 8,origin of ,species10 was scouted as wild speculation2 at present1 it is a sober statement of the conclusions to which an acute and critically-minded investigator is led by large and patient study of the facts of palontology4 ,i venture to repeat what ,i have said before1 that1 so far as the animal world is concerned1 evolution is no longer a speculation1 but a statement of historical fact4 ,it takes its place alongside of those accepted truths which must be reckoned with by philosophers of all schools4 ,thus when1 on the first day of ,october next1 the 8,origin of ,species0 comes of age1 the promise of its youth will be amply fulfilled2 and we shall be prepared to congratulate the venerated author of the book1 not only that the greatness of his achievement and its enduring influence upon the progress of knowledge have won him a place beside our ,harvey2 but1 still more1 that1 like ,harvey1 he has lived long enough to outlast detraction and opposition1 and to see the stone that the builders rejected become the head-stone of the corner4 ,,xiii4 ,,the ,,connection ,,of ,,the ,,biological ,,sciences ,,with ,,medicine4 ,the great body of theoretical and practical knowledge which has been accumulated by the labours of some eighty generations1 since the dawn of scientific thought in ,europe1 has no collective ,english name to which an objection may not be raised2 and ,i use the term 8medicine0 as that which is least likely to be misunderstood2 though1 as every one knows1 the name is commonly applied1 in a narrower sense1 to one of the chief divisions of the totality of medical science4 ,taken in this broad sense1 8medicine0 not merely denotes a kind of knowledge1 but it comprehends the various applications of that knowledge to the alleviation of the sufferings1 the repair of the injuries1 and the conservation of the health1 of living beings4 ,in fact1 the practical aspect of medicine so far dominates over every other1 that the 8,healing ,art0 is one of its most widely-received synonyms4 ,it is so difficult to think of medicine otherwise than as something which is necessarily connected with curative treatment1 that we are apt to forget that there must be1 and is1 such a thing as a pure science of medicine--a 8pathology0 which has no more necessary subservience to practical ends than has zoology or botany4 ,the logical connection between this purely scientific doctrine of disease1 or pathology1 and ordinary biology1 is easily traced4 ,living matter is characterised by its innate tendency to exhibit a definite series of the morphological and physiological phenomena which constitute organisation and life4 ,given a certain range of conditions1 and these phenomena remain the same1 within narrow limits1 for each kind of living thing4 ,they furnish the normal and typical character of the species1 and1 as such1 they are the subject-matter of ordinary biology4 ,outside the range of these conditions1 the normal course of the cycle of vital phenomena is disturbed2 abnormal structure makes its appearance1 or the proper character and mutual adjustment of the functions cease to be preserved4 ,the extent and the importance of these deviations from the typical life may vary indefinitely4 ,they may have no noticeable influence on the general well-being of the economy1 or they may favour it4 ,on the other hand1 they may be of such a nature as to impede the activities of the organism1 or even to involve its destruction4 ,in the first case1 these perturbations are ranged under the wide and somewhat vague category of 8variations20 in the second1 they are called lesions1 states of poisoning1 or diseases2 and1 as morbid states1 they lie within the province of pathology4 ,no sharp line of demarcation can be drawn between the two classes of phenomena4 ,no one can say where anatomical variations end and tumours begin1 nor where modification of function1 which may at first promote health1 passes into disease4 ,all that can be said is1 that whatever change of structure or function is hurtful belongs to pathology4 ,hence it is obvious that pathology is a branch of biology2 it is the morphology1 the physiology1 the distribution1 the tiology of abnormal life4 ,however obvious this conclusion may be now1 it was nowise apparent in the infancy of medicine4 ,for it is a peculiarity of the physical sciences1 that they are independent in proportion as they are imperfect2 and it is only as they advance that the bonds which really unite them all become apparent4 ,astronomy had no manifest connection with terrestrial physics before the publication of the 8,principia20 that of chemistry with physics is of still more modern revelation2 that of physics and chemistry with physiology1 has been stoutly denied within the recollection of most of us1 and perhaps still may be4 ,or1 to take a case which affords a closer parallel with that of medicine4 ,agriculture has been cultivated from the earliest times1 and1 from a remote antiquity1 men have attained considerable practical skill in the cultivation of the useful plants1 and have empirically established many scientific truths concerning the conditions under which they flourish4 ,but1 it is within the memory of many of us1 that chemistry on the one hand1 and vegetable physiology on the other1 attained a stage of development such that they were able to furnish a sound basis for scientific agriculture4 ,similarly1 medicine took its rise in the practical needs of mankind4 ,at first1 studied without reference to any other branch of knowledge1 it long maintained1 indeed still to some extent maintains1 that independence4 ,historically1 its connection with the biological sciences has been slowly established1 and the full extent and intimacy of that connection are only now beginning to be apparent4 ,i trust ,i have not been mistaken in supposing that an attempt to give a brief sketch of the steps by which a philosophical necessity has become an historical reality1 may not be devoid of interest1 possibly of instruction1 to the members of this great ,congress1 profoundly interested as all are in the scientific development of medicine4 ,the history of medicine is more complete and fuller than that of any other science1 except1 perhaps1 astronomy2 and1 if we follow back the long record as far as clear evidence lights us1 we find ourselves taken to the early stages of the civilisation of ,greece4 ,the oldest hospitals were the temples of sculapius2 to these ,asclepeia1 always erected on healthy sites1 hard by fresh springs and surrounded by shady groves1 the sick and the maimed resorted to seek the aid of the god of health4 ,votive tablets or inscriptions recorded the symptoms1 no less than the gratitude1 of those who were healed2 and1 from these primitive clinical records1 the half-priestly1 half-philosophic caste of the ,asclepiads compiled the data upon which the earliest generalisations of medicine1 as an inductive science1 were based4 ,in this state1 pathology1 like all the inductive sciences at their origin1 was merely natural history2 it registered the phenomena of disease1 classified them1 and ventured upon a prognosis1 wherever the observation of constant co-existences and sequences suggested a rational expectation of the like recurrence under similar circumstances4 ,further than this it hardly went4 ,in fact1 in the then state of knowledge1 and in the condition of philosophical speculation at that time1 neither the causes of the morbid state1 nor the rationale of treatment1 were likely to be sought for as we seek for them now4 ,the anger of a god was a sufficient reason for the existence of a malady1 and a dream ample warranty for therapeutic measures2 that a physical phenomenon must needs have a physical cause was not the implied or expressed axiom that it is to us moderns4 ,the great man whose name is inseparately connected with the foundation of medicine1 ,hippocrates1 certainly knew very little1 indeed practically nothing1 of anatomy or physiology2 and he would1 probably1 have been perplexed1 even to imagine the possibility of a connection between the zoological studies of his contemporary ,democritus and medicine4 ,nevertheless1 in so far as he1 and those who worked before and after him1 in the same spirit1 ascertained1 as matters of experience1 that a wound1 or a luxation1 or a fever1 presented such and such symptoms1 and that the return of the patient to health was facilitated by such and such measures1 they established laws of nature1 and began the construction of the science of pathology4 ,all true science begins with empiricism--though all true science is such exactly1 in so far as it strives to pass out of the empirical stage into that of the deduction of empirical from more general truths4 ,thus1 it is not wonderful1 that the early physicians had little or nothing to do with the development of biological science2 and1 on the other hand1 that the early biologists did not much concern themselves with medicine4 ,there is nothing to show that the ,asclepiads took any prominent share in the work of founding anatomy1 physiology1 zoology1 and botany4 ,rather do these seem to have sprung from the early philosophers1 who were essentially natural philosophers1 animated by the characteristically ,greek thirst for knowledge as such4 ,pythagoras1 ,alcmeon1 ,democritus1 ,diogenes of ,apollonia1 are all credited with anatomical and physiological investigations2 and1 though ,aristotle is said to have belonged to an ,asclepiad family1 and not improbably owed his taste for anatomical and zoological inquiries to the teachings of his father1 the physician ,nicomachus1 the 8,historia ,animalium10 and the treatise 8,de ,partibus ,animalium10 are as free from any allusion to medicine as if they had issued from a modern biological laboratory4 ,it may be added1 that it is not easy to see in what way it could have benefited a physician of ,alexander's time to know all that ,aristotle knew on these subjects4 ,his human anatomy was too rough to avail much in diagnosis2 his physiology was too erroneous to supply data for pathological reasoning4 ,but when the ,alexandrian school1 with ,erasistratus and ,herophilus at their head1 turned to account the opportunities of studying human structure1 afforded to them by the ,ptolemies1 the value of the large amount of accurate knowledge thus obtained to the surgeon for his operations1 and to the physician for his diagnosis of internal disorders1 became obvious1 and a connection was established between anatomy and medicine1 which has ever become closer and closer4 ,since the revival of learning1 surgery1 medical diagnosis1 and anatomy have gone hand in hand4 ,morgagni called his great work1 8,de sedibus et causis morborum per anatomen indagatis10 and not only showed the way to search out the localities and the causes of disease by anatomy1 but himself travelled wonderfully far upon the road4 ,bichat1 discriminating the grosser constituents of the organs and parts of the body1 one from another1 pointed out the direction which modern research must take2 until1 at length1 histology1 a science of yesterday1 as it seems to many of us1 has carried the work of ,morgagni as far as the microscope can take us1 and has extended the realm of pathological anatomy to the limits of the invisible world4 ,thanks to the intimate alliance of morphology with medicine1 the natural history of disease has1 at the present day1 attained a high degree of perfection4 ,accurate regional anatomy has rendered practicable the exploration of the most hidden parts of the organism1 and the determination1 during life1 of morbid changes in them2 anatomical and histological postmortem investigations have supplied physicians with a clear basis upon which to rest the classification of diseases1 and with unerring tests of the accuracy or inaccuracy of their diagnoses4 ,if men could be satisfied with pure knowledge1 the extreme precision with which1 in these days1 a sufferer may be told what is happening1 and what is likely to happen1 even in the most recondite parts of his bodily frame1 should be as satisfactory to the patient as it is to the scientific pathologist who gives him the information4 ,but ,i am afraid it is not2 and even the practising physician1 while nowise underestimating the regulative value of accurate diagnosis1 must often lament that so much of his knowledge rather prevents him from doing wrong than helps him to do right4 ,a scorner of physic once said that nature and disease may be compared to two men fighting1 the doctor to a blind man with a club1 who strikes into the mele1 sometimes hitting the disease1 and sometimes hitting nature4 ,the matter is not mended if you suppose the blind man's hearing to be so acute that he can register every stage of the struggle1 and pretty clearly predict how it will end4 ,he had better not meddle at all1 until his eyes are opened--until he can see the exact position of the antagonists1 and make sure of the effect of his blows4 ,but that which it behoves the physician to see1 not1 indeed1 with his bodily eye1 but with clear1 intellectual vision1 is a process1 and the chain of causation involved in that process4 ,disease1 as we have seen1 is a perturbation of the normal activities of a living body1 and it is1 and must remain1 unintelligible1 so long as we are ignorant of the nature of these normal activities4 ,in other words1 there could be no real science of pathology until the science of physiology had reached a degree of perfection unattained1 and indeed unattainable1 until quite recent times4 ,so far as medicine is concerned1 ,i am not sure that physiology1 such as it was down to the time of ,harvey1 might as well not have existed4 ,nay1 it is perhaps no exaggeration to say that1 within the memory of living men1 justly renowned practitioners of medicine and surgery knew less physiology than is now to be learned from the most elementary text-book2 and1 beyond a few broad facts1 regarded what they did know as of extremely little practical importance4 ,nor am ,i disposed to blame them for this conclusion2 physiology must be useless1 or worse than useless1 to pathology1 so long as its fundamental conceptions are erroneous4 ,harvey is often said to be the founder of modern physiology2 and there can be no question that the elucidations of the function of the heart1 of the nature of the pulse1 and of the course of the blood1 put forth in the ever-memorable little essay1 8,de motu cordis10 directly worked a revolution in men's views of the nature and of the concatenation of some of the most important physiological processes among the higher animals2 while1 indirectly1 their influence was perhaps even more remarkable4 ,but1 though ,harvey made this signal and perennially important contribution to the physiology of the moderns1 his general conception of vital processes was essentially identical with that of the ancients2 and1 in the 8,exercitationes de generatione10 and notably in the singular chapter 8,de calido innato10 he shows himself a true son of ,galen and of ,aristotle4 ,for ,harvey1 the blood possesses powers superior to those of the elements2 it is the seat of a soul which is not only vegetative1 but also sensitive and motor4 ,the blood maintains and fashions all parts of the body1 8idque summ cum providenti et intellectu in finem certum agens1 quasi ratiocinio quodam uteretur40 ,here is the doctrine of the 8pneuma10 the product of the philosophical mould into which the animism of primitive men ran in ,greece1 in full force4 ,nor did its strength abate for long after ,harvey's time4 ,the same ingrained tendency of the human mind to suppose that a process is explained when it is ascribed to a power of which nothing is known except that it is the hypothetical agent of the process1 gave rise1 in the next century1 to the animism of ,stahl2 and1 later1 to the doctrine of a vital principle1 that 8asylum ignoranti0 of physiologists1 which has so easily accounted for everything and explained nothing1 down to our own times4 ,now the essence of modern1 as contrasted with ancient1 physiological science appears to me to lie in its antagonism to animistic hypotheses and animistic phraseology4 ,it offers physical explanations of vital phenomena1 or frankly confesses that it has none to offer4 ,and1 so far as ,i know1 the first person who gave expression to this modern view of physiology1 who was bold enough to enunciate the proposition that vital phenomena1 like all the other phenomena of the physical world1 are1 in ultimate analysis1 resolvable into matter and motion1 was ,ren ,descartes4 ,the fifty-four years of life of this most original and powerful thinker are widely overlapped1 on both sides1 by the eighty of ,harvey1 who survived his younger contemporary by seven years1 and takes pleasure in acknowledging the ,french philosopher's appreciation of his great discovery4 ,in fact1 ,descartes accepted the doctrine of the circulation as propounded by 8,harvus mdecin d',angleterre10 and gave a full account of it in his first work1 the famous 8,discours de la ,mthode10 which was published in #afcg1 only nine years after the exercitation 8,de motu cordis20 and1 though differing from ,harvey on some important points 7in which it may be noted1 in passing1 ,descartes was wrong and ,harvey right71 he always speaks of him with great respect4 ,and so important does the subject seem to ,descartes1 that he returns to it in the 8,trait des ,passions10 and in the 8,trait de l',homme40 ,it is easy to see that ,harvey's work must have had a peculiar significance for the subtle thinker1 to whom we owe both the spiritualistic and the materialistic philosophies of modern times4 ,it was in the very year of its publication1 #afbh1 that ,descartes withdrew into that life of solitary investigation and meditation of which his philosophy was the fruit4 ,and1 as the course of his speculations led him to establish an absolute distinction of nature between the material and the mental worlds1 he was logically compelled to seek for the explanation of the phenomena of the material world within itself2 and having allotted the realm of thought to the soul1 to see nothing but extension and motion in the rest of nature4 ,descartes uses 8thought0 as the equivalent of our modern term 8consciousness40 ,thought is the function of the soul1 and its only function4 ,our natural heat and all the movements of the body1 says he1 do not depend on the soul4 ,death does not take place from any fault of the soul1 but only because some of the principal parts of the body become corrupted4 ,the body of a living man differs from that of a dead man in the same way as a watch or other automaton 7that is to say1 a machine which moves of itself7 when it is wound up and has1 in itself1 the physical principle of the movements which the mechanism is adapted to perform1 differs from the same watch1 or other machine1 when it is broken1 and the physical principle of its movement no longer exists4 ,all the actions which are common to us and the lower animals depend only on the conformation of our organs1 and the course which the animal spirits take in the brain1 the nerves1 and the muscles2 in the same way as the movement of a watch is produced by nothing but the force of its spring and the figure of its wheels and other parts4 ,descartes' 8,treatise on ,man0 is a sketch of human physiology1 in which a bold attempt is made to explain all the phenomena of life1 except those of consciousness1 by physical reasonings4 ,to a mind turned in this direction1 ,harvey's exposition of the heart and vessels as a hydraulic mechanism must have been supremely welcome4 ,descartes was not a mere philosophical theorist1 but a hardworking dissector and experimenter1 and he held the strongest opinion respecting the practical value of the new conception which he was introducing4 ,he speaks of the importance of preserving health1 and of the dependence of the mind on the body being so close that1 perhaps1 the only way of making men wiser and better than they are1 is to be sought in medical science4 8,it is true10 says he1 8that as medicine is now practised1 it contains little that is very useful2 but without any desire to depreciate1 ,i am sure that there is no one1 even among professional men1 who will not declare that all we know is very little as compared with that which remains to be known2 and that we might escape an infinity of diseases of the mind1 no less than of the body1 and even perhaps from the weakness of old age1 if we had sufficient knowledge of their causes1 and of all the remedies with which nature has provided us40#if ,so strongly impressed was ,descartes with this1 that he resolved to spend the rest of his life in trying to acquire such a knowledge of nature as would lead to the construction of a better medical doctrine4#ig ,the anti-,cartesians found material for cheap ridicule in these aspirations of the philosopher2 and it is almost needless to say that1 in the thirteen years which elapsed between the publication of the 8,discours0 and the death of ,descartes1 he did not contribute much to their realisation4 ,but1 for the next century1 all progress in physiology took place along the lines which ,descartes laid down4 ,the greatest physiological and pathological work of the seventeenth century1 ,borelli's treatise 8,de ,motu ,animalium10 is1 to all intents and purposes1 a development of ,descartes' fundamental conception2 and the same may be said of the physiology and pathology of ,boerhaave1 whose authority dominated in the medical world of the first half of the eighteenth century4 ,with the origin of modern chemistry1 and of electrical science1 in the latter half of the eighteenth century1 aids in the analysis of the phenomena of life1 of which ,descartes could not have dreamed1 were offered to the physiologist4 ,and the greater part of the gigantic progress which has been made in the present century is a justification of the prevision of ,descartes4 ,for it consists1 essentially1 in a more and more complete resolution of the grosser organs of the living body into physico-chemical mechanisms4 8,i shall try to explain our whole bodily machinery in such a way1 that it will be no more necessary for us to suppose that the soul produces such movements as are not voluntary1 than it is to think that there is in a clock a soul which causes it to show the hours40#ih ,these words of ,descartes might be appropriately taken as a motto by the author of any modern treatise on physiology4 ,but though1 as ,i think1 there is no doubt that ,descartes was the first to propound the fundamental conception of the living body as a physical mechanism1 which is the distinctive feature of modern1 as contrasted with ancient physiology1 he was misled by the natural temptation to carry out1 in all its details1 a parallel between the machines with which he was familiar1 such as clocks and pieces of hydraulic apparatus1 and the living machine4 ,in all such machines there is a central source of power1 and the parts of the machine are merely passive distributors of that power4 ,the ,cartesian school conceived of the living body as a machine of this kind2 and herein they might have learned from ,galen1 who1 whatever ill use he may have made of the doctrine of 8natural faculties10 nevertheless had the great merit of perceiving that local forces play a great part in physiology4 ,the same truth was recognised by ,glisson1 but it was first prominently brought forward in the ,hallerian doctrine of the 8vis insita0 of muscles4 ,if muscle can contract without nerve1 there is an end of the ,cartesian mechanical explanation of its contraction by the influx of animal spirits4 ,the discoveries of ,trembley tended in the same direction4 ,in the freshwater ,hydra1 no trace was to be found of that complicated machinery upon which the performance of the functions in the higher animals was supposed to depend4 ,and yet the hydra moved1 fed1 grew1 multiplied1 and its fragments exhibited all the powers of the whole4 ,and1 finally1 the work of ,caspar ,f4 ,wolff1#ii by demonstrating the fact that the growth and development of both plants and animals take place antecedently to the existence of their grosser organs1 and are1 in fact1 the causes and not the consequences of organisation 7as then understood71 sapped the foundations of the ,cartesian physiology as a complete expression of vital phenomena4 ,for ,wolff1 the physical basis of life is a fluid1 possessed of a 8vis essentialis0 and a 8solidescibilitas10 in virtue of which it gives rise to organisation2 and1 as he points out1 this conclusion strikes at the root of the whole iatro-mechanical system4 ,in this country1 the great authority of ,john ,hunter exerted a similar influence2 though it must be admitted that the too sibylline utterances which are the outcome of ,hunter's struggles to define his conceptions are often susceptible of more than one interpretation4 ,nevertheless1 on some points ,hunter is clear enough4 ,for example1 he is of opinion that 8,spirit is only a property of matter0 78,introduction to ,natural ,history10 p4 #f71 he is prepared to renounce animism 7l4c4 p4 #h71 and his conception of life is so completely physical that he thinks of it as something which can exist in a state of combination in the food4 8,the aliment we take in has in it1 in a fixed state1 the real life2 and this does not become active until it has got into the lungs2 for there it is freed from its prison0 78,observations on ,physiology10 p4 #aac74 ,he also thinks that 8,it is more in accord with the general principles of the animal machine to suppose that none of its effects are produced from any mechanical principle whatever2 and that every effect is produced from an action in the part2 which action is produced by a stimulus upon the part which acts1 or upon some other part with which this part sympathises so as to take up the whole action0 7l4c4 p4 #aeb74 ,and ,hunter is as clear as ,wolff1 with whose work he was probably unacquainted1 that 8whatever life is1 it most certainly does not depend upon structure or organisation0 7l4c4 p4 #aad74 ,of course it is impossible that ,hunter could have intended to deny the existence of purely mechanical operations in the animal body4 ,but while1 with ,borelli and ,boerhaave1 he looked upon absorption1 nutrition1 and secretion as operations effected by means of the small vessels1 he differed from the mechanical physiologists1 who regarded these operations as the result of the mechanical properties of the small vessels1 such as the size1 form1 and disposition of their canals and apertures4 ,hunter1 on the contrary1 considers them to be the effect of properties of these vessels which are not mechanical but vital4 8,the vessels10 says he1 8have more of the polypus in them than any other part of the body10 and he talks of the 8living and sensitive principles of the arteries10 and even of the 8dispositions or feelings of the arteries40 8,when the blood is good and genuine the sensations of the arteries1 or the dispositions for sensation1 are agreeable4444 ,it is then they dispose of the blood to the best advantage1 increasing the growth of the whole1 supplying any losses1 keeping up a due succession1 etc40 7l4c4 p4 #acc74 ,if we follow ,hunter's conceptions to their logical issue1 the life of one of the higher animals is essentially the sum of the lives of all the vessels1 each of which is a sort of physiological unit1 answering to a polype2 and1 as health is the result of the normal 8action of the vessels10 so is disease an effect of their abnormal action4 ,hunter thus stands in thought1 as in time1 midway between ,borelli on the one hand1 and ,bichat on the other4 ,the acute founder of general anatomy1 in fact1 outdoes ,hunter in his desire to exclude physical reasonings from the realm of life4 ,except in the interpretation of the action of the sense organs1 he will not allow physics to have anything to do with physiology4 8,to apply the physical sciences to physiology is to explain the phenomena of living bodies by the laws of inert bodies4 ,now this is a false principle1 hence all its consequences are marked with the same stamp4 ,let us leave to chemistry its affinity2 to physics1 its elasticity and its gravity4 ,let us invoke for physiology only sensibility and contractility40#ajj ,of all the unfortunate dicta of men of eminent ability this seems one of the most unhappy1 when we think of what the application of the methods and the data of physics and chemistry has done towards bringing physiology into its present state4 ,it is not too much to say that one half of a modern text-book of physiology consists of applied physics and chemistry2 and that it is exactly in the exploration of the phenomena of sensibility and contractility that physics and chemistry have exerted the most potent influence4 ,nevertheless1 ,bichat rendered a solid service to physiological progress by insisting upon the fact that what we call life1 in one of the higher animals1 is not an indivisible unitary archus dominating1 from its central seat1 the parts of the organism1 but a compound result of the synthesis of the separate lives of those parts4 8,all animals10 says he1 8are assemblages of different organs1 each of which performs its function and concurs1 after its fashion1 in the preservation of the whole4 ,they are so many special machines in the general machine which constitutes the individual4 ,but each of these special machines is itself compounded of many tissues of very different natures1 which in truth constitute the elements of those organs0 7l4c4 lxxix47 8,the conception of a proper vitality is applicable only to these simple tissues1 and not to the organs themselves0 7l4c4 lxxxiv47 ,and ,bichat proceeds to make the obvious application of this doctrine of synthetic life1 if ,i may so call it1 to pathology4 ,since diseases are only alterations of vital properties1 and the properties of each tissue are distinct from those of the rest1 it is evident that the diseases of each tissue must be different from those of the rest4 ,therefore1 in any organ composed of different tissues1 one may be diseased and the other remain healthy2 and this is what happens in most cases 7l4c4 lxxxv47 ,in a spirit of true prophecy1 ,bichat says1 8,we have arrived at an epoch1 in which pathological anatomy should start afresh40 ,for1 as the analysis of the organs had led him to the tissues1 as the physiological units of the organism2 so1 in a succeeding generation1 the analysis of the tissues led to the cell as the physiological element of the tissues4 ,the contemporaneous study of development brought out the same result2 and the zoologists and botanists1 exploring the simplest and the lowest forms of animated beings1 confirmed the great induction of the cell theory4 ,thus the apparently opposed views1 which have been battling with one another ever since the middle of the last century1 have proved to be each half the truth4 ,the proposition of ,descartes that the body of a living man is a machine1 the actions of which are explicable by the known laws of matter and motion1 is unquestionably largely true4 ,but it is also true1 that the living body is a synthesis of innumerable physiological elements1 each of which may nearly be described1 in ,wolff's words1 as a fluid possessed of a 8vis essentialis10 and a 8solidescibilitas02 or1 in modern phrase1 as protoplasm susceptible of structural metamorphosis and functional metabolism3 and that the only machinery1 in the precise sense in which the ,cartesian school understood mechanism1 is1 that which co-ordinates and regulates these physiological units into an organic whole4 ,in fact1 the body is a machine of the nature of an army1 not of that of a watch or of a hydraulic apparatus4 ,of this army each cell is a soldier1 an organ a brigade1 the central nervous system headquarters and field telegraph1 the alimentary and circulatory system the commissariat4 ,losses are made good by recruits born in camp1 and the life of the individual is a campaign1 conducted successfully for a number of years1 but with certain defeat in the long run4 ,the efficacy of an army1 at any given moment1 depends on the health of the individual soldier1 and on the perfection of the machinery by which he is led and brought into action at the proper time2 and1 therefore1 if the analogy holds good1 there can be only two kinds of diseases1 the one dependent on abnormal states of the physiological units1 the other on perturbations of their co-ordinating and alimentative machinery4 ,hence1 the establishment of the cell theory1 in normal biology1 was swiftly followed by a 8cellular pathology10 as its logical counterpart4 ,i need not remind you how great an instrument of investigation this doctrine has proved in the hands of the man of genius to whom its development is due1 and who would probably be the last to forget that abnormal conditions of the co-ordinative and distributive machinery of the body are no less important factors of disease4 ,henceforward1 as it appears to me1 the connection of medicine with the biological sciences is clearly defined4 ,pure pathology is that branch of biology which defines the particular perturbation of cell-life1 or of the co-ordinating machinery1 or of both1 on which the phenomena of disease depend4 ,those who are conversant with the present state of biology will hardly hesitate to admit that the conception of the life of one of the higher animals as the summation of the lives of a cell aggregate1 brought into harmonious action by a co-ordinative machinery formed by some of these cells1 constitutes a permanent acquisition of physiological science4 ,but the last form of the battle between the animistic and the physical views of life is seen in the contention whether the physical analysis of vital phenomena can be carried beyond this point or not4 ,there are some to whom living protoplasm is a substance1 even such as ,harvey conceived the blood to be1 8summ cum providenti et intellectu in finem certum agens1 quasi ratiocinio quodam20 and who look with as little favour as ,bichat did1 upon any attempt to apply the principles and the methods of physics and chemistry to the investigation of the vital processes of growth1 metabolism1 and contractility4 ,they stand upon the ancient ways2 only1 in accordance with that progress towards democracy1 which a great political writer has declared to be the fatal characteristic of modern times1 they substitute a republic formed by a few billion of 8animul0 for the monarchy of the all-pervading 8anima40 ,others1 on the contrary1 supported by a robust faith in the universal applicability of the principles laid down by ,descartes1 and seeing that the actions called 8vital0 are1 so far as we have any means of knowing1 nothing but changes of place of particles of matter1 look to molecular physics to achieve the analysis of the living protoplasm itself into a molecular mechanism4 ,if there is any truth in the received doctrines of physics1 that contrast between living and inert matter1 on which ,bichat lays so much stress1 does not exist4 ,in nature1 nothing is at rest1 nothing is amorphous2 the simplest particle of that which men in their blindness are pleased to call 8brute matter0 is a vast aggregate of molecular mechanisms performing complicated movements of immense rapidity1 and sensitively adjusting themselves to every change in the surrounding world4 ,living matter differs from other matter in degree and not in kind2 the microcosm repeats the macrocosm2 and one chain of causation connects the nebulous original of suns and planetary systems with the protoplasmic foundation of life and organisation4 ,from this point of view1 pathology is the analogue of the theory of perturbations in astronomy2 and therapeutics resolves itself into the discovery of the means by which a system of forces competent to eliminate any given perturbation may be introduced into the economy4 ,and1 as pathology bases itself upon normal physiology1 so therapeutics rests upon pharmacology2 which is1 strictly speaking1 a part of the great biological topic of the influence of conditions on the living organism1 and has no scientific foundation apart from physiology4 ,it appears to me that there is no more hopeful indication of the progress of medicine towards the ideal of ,descartes than is to be derived from a comparison of the state of pharmacology1 at the present day1 with that which existed forty years ago4 ,if we consider the knowledge positively acquired1 in this short time1 of the modus operandi of urari1 of atropia1 of physostigmin1 of veratria1 of casca1 of strychnia1 of bromide of potassium1 of phosphorus1 there can surely be no ground for doubting that1 sooner or later1 the pharmacologist will supply the physician with the means of affecting1 in any desired sense1 the functions of any physiological element of the body4 ,it will1 in short1 become possible to introduce into the economy a molecular mechanism which1 like a very cunningly-contrived torpedo1 shall find its way to some particular group of living elements1 and cause an explosion among them1 leaving the rest untouched4 ,the search for the explanation of diseased states in modified cell-life2 the discovery of the important part played by parasitic organisms in the tiology of disease2 the elucidation of the action of medicaments by the methods and the data of experimental physiology2 appear to me to be the greatest steps which have ever been made towards the establishment of medicine on a scientific basis4 ,i need hardly say they could not have been made except for the advance of normal biology4 ,there can be no question1 then1 as to the nature or the value of the connection between medicine and the biological sciences4 ,there can be no doubt that the future of pathology and of therapeutics1 and1 therefore1 that of practical medicine1 depends upon the extent to which those who occupy themselves with these subjects are trained in the methods and impregnated with the fundamental truths of biology4 ,and1 in conclusion1 ,i venture to suggest that the collective sagacity of this ,congress could occupy itself with no more important question than with this3 ,how is medical education to be arranged1 so that1 without entangling the student in those details of the systematist which are valueless to him1 he may be enabled to obtain a firm grasp of the great truths respecting animal and vegetable life1 without which1 notwithstanding all the progress of scientific medicine1 he will still find himself an empiric8 ,,footnotes3 #a ,see ,joseph ,priestley1 p4 #id1 infra4 #b ,the advocacy of the introduction of physical science into general education by ,george ,combe and others commenced a good deal earlier2 but the movement had acquired hardly any practical force before the time to which ,i refer4 #c ,essays in ,criticism1 p4 #cg4 #d 8,quamvis enim melius sit bene facere quam nosse1 prius tamen est nosse quam facere40--8,karoli ,magni ,regis ,constitutio de ,scholis per singula ,episcopia et ,monasteria instituendis10 addressed to the ,abbot of ,fulda4 ,baluzius1 8,capitularia ,regum ,francorum10 ,t4 i41 p4 #bjb4 #e ,inaugural ,address delivered to the ,university of ,st4 ,andrew ,february #a1 #ahfg1 by ,j4 ,s4 ,mill1 ,rector of the ,university 7pp4 #cb1 #cc74 #f 8,suggestions for ,academical ,organisation1 with ,especial ,reference to ,oxford40 ,by the ,rector of ,lincoln4 #g ,goethe1 ,zahme ,xenien1 ,vierte ,abtheilung4 ,i should be glad to take credit for the close and vigorous ,english version2 but it is my wife's1 and not mine4 #h ,see the 8,programme0 for #ahgh1 issued by the ,society of ,arts1 p4 #ad4 #i ,it is perhaps advisable to remark that the important question of the professional education of managers of industrial works is not touched in the foregoing remarks4 #aj 8,quasi cursores1 vita lampada tradunt40--,,lucr4 ,de ,rerum ,nat4 ii4 #gh4 #aa 8,life and ,correspondence of ,dr4 ,priestley10 by ,j4 ,t4 ,rutt4 ,vol4 i4 p4 #ej4 #ab 8,autobiography10 #ajj1 #aja4 #ac ,see 8,the ,life of ,mary ,anne ,schimmelpenninck40 ,mrs4 ,schimmelpenninck 7ne ,galton7 remembered ,priestley very well1 and her description of him is worth quotation3--8,a man of admirable simplicity1 gentleness and kindness of heart1 united with great acuteness of intellect4 ,i can never forget the impression produced on me by the serene expression of his countenance4 ,he1 indeed1 seemed present with ,god by recollection1 and with man by cheerfulness4 ,i remember that1 in the assembly of these distinguished men1 amongst whom ,mr4 ,boulton1 by his noble manner1 his fine countenance 7which much resembled that of ,louis ,,xiv471 and princely munificence1 stood pre-eminently as the great ,mecnas2 even as a child1 ,i used to feel1 when ,dr4 ,priestley entered after him1 that the glory of the one was terrestrial1 that of the other celestial2 and utterly far as ,i am removed from a belief in the sufficiency of ,dr4 ,priestley's theological creed1 ,i cannot but here record this evidence of the eternal power of any portion of the truth held in its vitality40 #ad ,even ,mrs4 ,priestley1 who might be forgiven for regarding the destroyers of her household gods with some asperity1 contents herself1 in writing to ,mrs4 ,barbauld1 with the sarcasm that the ,birmingham people 8will scarcely find so many respectable characters1 a second time1 to make a bonfire of40 #ae 8,experiments and ,observations on ,different ,kinds of ,air10 vol4 ii4 p4 #ca4 #af ,ibid4 pp4 #cd1 #ce4 #ag 8,experiments and ,observations on ,different ,kinds of ,air10 vol4 ii4 p4 #dj4 #ah ,ibid4 p4 #dh4 #ai ,ibid4 p4 #ee4 #bj 8,experiments and ,observations on ,different ,kinds of ,air10 vol4 ii4 p4 #fj4 ,the italics are ,priestley's own4 #ba 8,in all the newspapers and most of the periodical publications ,i was represented as an unbeliever in ,revelation1 and no better than an atheist40--8,autobiography10 ,rutt4 vol4 i4 p4 #abd4 8,on the walls of houses1 etc41 and especially where ,i usually went1 were to be seen1 in large characters1 #8,,madan ,,for ,,ever2 ,,damn ,,priestley2 ,,no ,,presbyterianism2 ,,damn ,,the ,,presbyterians1' etc4 etc42 and1 at one time1 ,i was followed by a number of boys1 who left their play1 repeating what they had seen on the walls1 and shouting out1 #8,damn ,priestley2 damn him1 damn him1 for ever1 for ever1' etc4 etc4 ,this was no doubt a lesson which they had been taught by their parents1 and what they1 ,i fear1 had learned from their superiors40--8,appeal to the ,public on the ,subject of the ,riots at ,birmingham40 #bb ,first ,series4 8,on ,some of the ,peculiarities of the ,christian ,religion40 ,essay ,i4 ,revelation of a ,future ,state4 #bc ,not only is ,priestley at one with ,bishop ,courtenay in this matter1 but with ,hartley and ,bonnet1 both of them stout champions of ,christianity4 ,moreover1 ,archbishop ,whately's essay is little better than an expansion of the first paragraph of ,hume's famous essay on the ,immortality of the ,soul3--8,by the mere light of reason it seems difficult to prove the immortality of the soul2 the arguments for it are commonly derived either from metaphysical topics1 or moral1 or physical4 ,but it is in reality the ,gospel1 and the ,gospel alone1 that has brought life and immortality to light40 ,it is impossible to imagine that a man of ,whately's tastes and acquirements had not read ,hume or ,hartley1 though he refers to neither4 #bd 8,essay on the ,first ,principles of ,government40 ,second edition1 #agga1 p4 #ac4 #be 8,utility of ,establishments10 in 8,essay on ,first ,principles of ,government10 p4 #aih1 #agga4 #bf ,in #agcb ,doddridge was cited for teaching without the ,bishop's leave1 at ,northampton4 #bg ,the recent proceedings of the ,house of ,commons throw a doubt1 which it is to be hoped may speedily be removed1 on the accuracy of this statement4 7,september #ahha47 #bh 8,discours sur les rvolutions de la surface du globe10 ,recherches sur les ossemens fossiles1 ,ed4 iv4 t4 i4 p4 #ahe4 #bi 8,on the ,eclipses of ,agathocles1 ,thales1 and ,xerxes10 ,philosophical ,transactions1 vol4 cxliii4 #cj ,there is every reason to believe that living plants1 like living animals1 always respire1 and1 in respiring1 absorb oxygen and give off carbonic acid2 but1 that in green plants exposed to daylight or to the electric light1 the quantity of oxygen evolved in consequence of the decomposition of carbonic acid by a special apparatus which green plants possess exceeds that absorbed in the concurrent respiratory process4 #ca ,darwin1 8,insectivorous ,plants10 p4 #bhi4 #cb ,i purposely assume that the air with which the bean is supplied in the case stated contains no ammoniacal salts4 #cc ,the recent researches of ,pringsheim have raised a host of questions as to the exact share taken by chlorophyll in the chemical operations which are effected by the green parts of plants4 ,it may be that the chlorophyll is only a constant concomitant of the actual deoxidising apparatus4 #cd 8,researches in the ,life-history of a ,cercomonad3 a ,lesson in ,biogenesis20 and 8,further ,researches in the ,life-history of the ,monads40--8,monthly ,microscopical ,journal10 #ahgc4 #ce ,excellently described by ,stein1 almost all of whose statements ,i have verified4 #cf 8,histoire des ,sciences ,naturelles10 i4 p4 #aeb4 #cg ,the text ,i have followed is that given by ,aubert and ,wimmer1 8,aristoteles ,thierkunde2 kritisch berichtigter ,text mit deutschen ,uebersetzung20 but ,i have tried here and there to bring the ,english version rather closer to the original than the ,german translation1 excellent as it is1 seems to me to be4 #ch ,in modern works on ,veterinary ,anatomy the lungs are sometimes described as two lobes of a single organ4 #ci 8,histoire des ,sciences ,naturelles40--t4 i4 p4 #acj4 #dj 8,aristotle1 a ,chapter from the ,history of ,science40 #da ,i quote1 here and always1 ,cousin's edition of the works of ,descartes1 as most convenient for reference4 ,it is entitled 8uvres compltes de ,descartes10 publies par ,victor ,cousin4 #ahbd4 #db 8,les ,passions de l'me10 ,article xxxiii4 #dc 8,recherches physiologiques sur la ,vie et la ,mort40 ,par ,xav4 ,bichat4 ,art4 ,sixime4 #dd ,locke 7,human ,understanding1 ,book ,,ii41 chap4 viii4 #cg7 uses ,descartes' illustration for the same purpose1 and warns us that 8most of the ideas of sensation are no more the likeness of something existing without us than the names that stand for them are the likeness of our ideas1 which yet1 upon hearing1 they are apt to excite in us10 a declaration which paved the way for ,berkeley4 #de 8,passions de l'me10 ,art4 xxxvi4 #df 8,quamcumque ,bruti actionem1 velut automati mechanici motum artificialem1 in eo consistere quod se prim sensibile aliquod spiritus animales afficiens1 eosque introrsum convertens1 sensionem excitat1 qua mox iidem spiritus1 velut undulatione reflex denuo retrorsum commoti atque pro concinno ipsius fabric organorum1 et partium ordine1 in certos nervos musculosque determinati1 respectivos membrorum motus perficiunt40--,,willis3 8,de ,anim ,brutorum10 p4 #e1 ed4 #agfc4 #dg 8,les ,passions de l'me10 xlii4 #dh ,haller1 8,prim ,line10 ed4 iii4 8,sensus ,interni10 dlviii4 #di 8,rponse de ,m4 ,descartes ,m4 ,morus40 #afdi4 8uvres10 tome x4 p4 #bjd4 8,mais le plus grand de tous les prjugs que nous ayons retenus de notre enfance1 est celui de croire que les btes pensent10 etc4 #ej ,malebranche states the view taken by orthodox ,cartesians in #afhi very forcibly3 8,ainsi dans les chiens1 les chats1 et les autres animaux1 il n'y a ny intelligence1 ny me spirituelle comme on l'entend ordinairement4 ,ils mangent sans plaisir2 ils crient sans douleur2 ils croissent sans le savoir2 ils ne dsirent rien2 ils ne connoissent rien2 et s'ils agissent avec adresse et d'une manire qui marque l'intelligence1 c'est que ,dieu les faisant pour les conserver1 il a conform leurs corps de telle manire1 qu'ils vitent organiquement1 sans le savoir1 tout ce qui peut les dtruire et qu'ils semblent craindre40 78,feuillet de ,conches4 ,mditations ,mtaphysiques et ,correspondance de ,n4 ,malebranche4 ,neuvime ,mditation40 #ahda47 #ea ,see the remarkable essay of ,gltz1 8,beitrge zur ,lehre von den ,functionen der ,nervencentren des ,frosches10 published in #ahfi4 ,i have repeated ,gltz's experiments1 and obtained the same results4 #eb 8,de l',automatisme de la ,mmoire et du ,souvenir1 dans le ,somnambulisme pathologique40 ,par le ,dr4 ,e4 ,mesnet1 ,mdecin de l',hpital ,saint-,antoine4 8,l',union ,mdicale10 ,juillet #ba et #bc1 #ahgd4 ,my attention was first called to a summary of this remarkable case1 which appeared in the 8,journal des ,dbats0 for the #gth of ,august #ahgd1 by my friend ,general ,strachey1 ,f4,r4,s4 #ec ,those who have had occasion to become acquainted with the phenomena of somnambulism and of mesmerism1 will be struck with the close parallel which they present to the proceedings of ,f4 in his abnormal state4 ,but the great value of ,dr4 ,mesnet's observations lies in the fact that the abnormal condition is traceable to a definite injury to the brain1 and that the circumstances are such as to keep us clear of the cloud of voluntary and involuntary fictions in which the truth is too often smothered in such cases4 ,in the unfortunate subjects of such abnormal conditions of the brain1 the disturbance of the sensory and intellectual faculties is not unfrequently accompanied by a perturbation of the moral nature1 which may manifest itself in a most astonishing love of lying for its own sake4 ,and1 in this respect1 also1 ,f4's case is singularly instructive1 for though1 in his normal state1 he is a perfectly honest man1 in his abnormal condition he is an inveterate thief1 stealing and hiding away whatever he can lay hands on1 with much dexterity1 and with an absurd indifference as to whether the property is his own or not4 ,hoffman's terrible conception of the 8,doppelt-gnger0 is realised by men in this state--who live two lives1 in the one of which they may be guilty of the most criminal acts1 while1 in the other1 they are eminently virtuous and respectable4 ,neither life knows anything of the other4 ,dr4 ,mesnet states that he has watched a man in his abnormal state elaborately prepare to hang himself1 and has let him go on until asphyxia set in1 when he cut him down4 ,but on passing into the normal state the would-be suicide was wholly ignorant of what had happened4 ,the problem of responsibility is here as complicated as that of the prince-bishop1 who swore as a prince and not as a bishop4 8,but1 highness1 if the prince is damned1 what will become of the bishop80 said the peasant4 #ed 8,lay ,sermons1 ,essays and ,reviews10 p4 #cee4 #ee 8,essai de ,psychologie10 chap4 xxvii4 #ef ,in justice to ,reid1 however1 it should be stated that the chapters on sensation in the 8,essays on the ,intellectual ,powers0 7#aghe7 exhibit a great improvement4 ,he is1 in fact1 in advance of his commentator1 as the note to ,essay ,,ii4 chap4 ii4 p4 #bdh of ,hamilton's edition shows4 #eg ,haller1 amplifying ,descartes1 writes in the 8,prim ,line10 ,,ccclxvi4--8,non est adeo obscurum sensum omnem oriri ab objecti sensibilis impressione in nervum quemcumque corporis humani1 et eamdem per eum nervum ad cerebrum pervenientem tunc demum representari anim1 quando cerebrum adtigit4 ,ut etiam hoc falsum sit animam inproximo per sensoria nervorumque ramos sentire40444 ,,dlvii4--8,dum ergo sentimus quinque diversissima entia conjunguntur3 corpus quod sentimus3 organi sensorii adfectio ab eo corpore3 cerebri adfectio a sensorii percussione nata3 in anima nata mutatio3 anim denique conscientia et sensationis adperceptio40 ,nevertheless1 ,sir ,william ,hamilton gravely informs his hearers3--8,we have no more right to deny that the mind feels at the finger points1 as consciousness assures us1 than to assert that it thinks exclusively in the brain40--8,lecture on ,metaphysics and ,logic10 ii4 p4 #abh4 8,we have no reason whatever to doubt the report of consciousness1 that we actually perceive at the external point of sensation1 and that we perceive the material reality40--,ibid4 p4 #abi4 #eh 8,observations on ,man10 vol4 i4 p4 #aa4 #ei ,ibid4 p4 #h4 ,the speculations of ,bonnet are remarkably similar to those of ,hartley2 and they appear to have originated independently1 though the 8,essai de ,psychologie0 7#aged7 is of five years' later date than the 8,observations on ,man0 7#agdi74 #fj 8,an ,inquiry into the ,human ,mind on the ,principles of ,common ,sense10 chap4 ii4 #b4 ,reid affirms that 8it is genius1 and not the want of it1 that adulterates philosophy1 and fills it with error and false theory20 and no doubt his own lucubrations are free from the smallest taint of the impurity to which he objects4 ,but1 for want of something more than that sort of 8common sense10 which is very common and a little dull1 the contemner of genius did not notice that the admission here made knocks so big a hole in the bottom of 8common sense philosophy10 that nothing can save it from foundering in the dreaded abyss of ,idealism4 #fa ,the following diagrammatic scheme may help to elucidate the theory of sensation3-- ,mediate ,knowledge ,immediate ,sensiferous ,apparatus ,knowledge ,objects of sense ,receptive ,transmissive ,sensificatory ,sensations and 7,sense ,organ7 7,nerve7 7,sensorium7 other ,states of ,consciousness ,hypothetical ,hypothetical ,substance of ,substance of ,matter ,mind ,physical ,world ,mental ,world ,not ,self ,self ,non-,ego or ,object ,ego or ,subject ,immediate knowledge is confined to states of consciousness1 or1 in other words1 to the phenomena of mind4 ,knowledge of the physical world1 or of one's own body and of objects external to it1 is a system of beliefs or judgments based on the sensations4 ,the term 8self0 is applied not only to the series of mental phenomena which constitute the ego1 but to the fragment of the physical world which is their constant concomitant4 ,the corporeal self1 therefore1 is part of the non-ego2 and is objective in relation to the ego as subject4 #fb 8,chaque fibre est une espce de touche ou de marteau destin rendre un certain ton40--,bonnet1 8,essai de ,psychologie10 chap4 iv4 #fc ,the 8,exercitationes de ,generatione ,animalium10 which ,dr4 ,george ,ent extracted from him and published in #afea4 #fd 8,de ,generatione ,animalium10 lib ii4 cap4 x4 #fe 8,de ,generatione10 lib4 ii4 cap4 iv4 #ff 8,cependant1 pour revenir aux formes ordinaires ou aux mes matrielles1 cette dure qu'il leur faut attribuer la place de celle qu'on avoit attribute aux atomes pourroit faire douter si elles ne vont pas de corps en corps2 ce qui seroit la mtempsychose1 peu prs comme quelques philosophes ont cru la transmission du mouvement et celle des espces4 ,mais cette imagination est bien loigne de la nature des choses4 ,il n'y a point de tel passage2 et c'est ici o les transformations de ,messieurs ,swammerdam1 ,malpighi1 et ,leewenhoek1 qui sont des plus excellens observateurs de notre tems1 sont venues mon secours1 et m'ont fait admettre plus aisment1 que l'animal1 et toute autre substance organise ne commence point lorsque nous le croyons1 et que sa generation apparente n'est qu'une dveloppement et une espce d'augmentation4 ,aussi ai je remarqu que l'auteur de la 8,recherche de la ,verit10 ,m4 ,regis1 ,m4 ,hartsocker1 et d'autres habiles hommes n'ont pas t fort loigns de ce sentiment40 ,leibnitz1 8,systme nouveau de la ,nature10 #afie4 ,the doctrine of 8,embotement0 is contained in the 8,considrations sur le principe de vie10 #agje2 the preface to the 8,theodice10 #agaj2 and the 8,principes de la ,nature et de la ,grace0 7 #f71 #agah4 #fg 8,il est vrai que la pense la plus raisonnable et la plus conforme l'experience sur cette question trs difficile de la formation du ftus2 c'est que les enfans sont dja presque tout forms avant mme l'action par laquelle ils sont conus2 et que leurs mres ne font que leur donner l'accroissement ordinaire dans le temps de la grossesse40 8,de la ,recherche de la ,verit10 livre ii4 chap4 vii4 p4 #ccd1 #gth ed41 #agba4 #fh ,the writer is indebted to ,dr4 ,allen ,thomson for reference to the evidence contained in a note to ,haller's edition of ,boerhaave's 8,prlectiones ,academic10 vol4 v4 pt ii4 p4 #dig1 published in #agdd1 that ,haller originally advocated epigenesis4 #fi 8,considrations sur les ,corps organiss10 chap4 x4 #gj ,bonnet had the courage of his opinions1 and in the 8,palingnsie ,philosophique10 part vi4 chap1 iv41 he develops a hypothesis which he terms 8volution naturelle20 and which1 making allowance for his peculiar views of the nature of generation1 bears no small resemblance to what is understood by 8evolution0 at the present day3-- 8,si la volont divine a cr par un seul ,acte l',universalit des tres1 d'o venoient ces plantes et ces animaux dont ,moyse nous decrit la ,production au troisieme et au cinquieme jour du renouvellement de notre monde8 8,abuserois-je de la libert de conjectures si je disois1 que les ,plantes et les ,animaux qui existent aujourd'hui sont parvenus par une sorte d'evolution naturelle des ,etres organiss qui peuplaient ce premier ,monde1 sorti immdiatement des ,,mains du ,,createur8444 8,ne supposons que trois rvolutions4 ,la ,terre vient de sortir des ,,mains du ,,createur4 ,des causes prepares par sa ,,sagesse font dvelopper de toutes parts les ,germes4 ,les ,etres organiss commencent jouir de l'existence4 ,ils toient probablement alors bien diffrens de ce qu'ils sont aujourd'hui4 ,ils l'etoient autant que ce premier ,monde diffroit de celui que nous habitons4 ,nous manquons de moyens pour juger de ces dissemblances1 et peut-tre que le plus habile ,naturaliste qui auroit t plac dans ce premier ,monde y auroit entirement mconnu nos ,plantes et nos ,animaux40 #ga 8,ce mot 7germe7 ne dsignera pas seulement un corps organis rduit en petit2 il dsignera encore toute espce de prformation originelle dont un ,tout organique pent rsulter comme de son principe immdiat40--8,palingnsie ,philosophique10 part x4 chap4 ii4 #gb 8,m4 ,cuvier considrant que tous les tres organiss sont drivs de parens1 et ne voyant dans la nature aucune force capable de produire l'organisation1 croyait la pr-existence des germes2 non pas la pr-existence d'un tre tout form1 puisqu'il est bien vident que ce n'est que par des dveloppemens successifs que l'tre acquiert sa forme2 mais1 si l'on peut s'exprimer ainsi1 la pr-existence du radical de l'tre1 radical qui existe avant que la srie des volutions ne commence1 et qui remonte certainement1 suivant la belle observation de ,bonnet1 plusieurs generations40--,laurillard1 8loge de ,cuvier10 note #ab4 #gc 8,histoire ,naturelle10 tom4 ii4 ed4 ii4 #agej1 p4 #cej4 #gd ,ibid4 p4 #cea4 #ge ,see particularly ,buffon1 l4c4 p4 #da4 #gf 8,exercitationes de ,generatione40 ,ex4 #fb1 8,ovum esse primordium commune omnibus animalibus40 #gg ,in some cases of sexless multiplication the germ is a cell-aggregate--if we call germ only that which is already detached from the parent organism4 #gh ,harvey1 8,exercitationes de ,generatione40 ,ex4 #de1 8,qunam sit pulli materia et quomodo fiat in ,ovo40 #gi ,not yet actually demonstrated in the case of phnogamous plants4 #hj ,as ,buffon has well said3--8,l'ide de ramener l'explication de tous les phnomnes des principes mecaniques est assurement grande et belle1 ce pas est le plus hardi qu'on peut faire en philosophie1 et c'est ,descartes qui l'a fait40--l4c4 p4 #ej4 #ha 8,principes de la ,philosophie10 ,troisime partie1 #de4 #hb 8,ethices10 ,pars tertia1 ,prfatio4 #hc 8,systme de la ,nature40 8,essai sur la ,formation des ,corps ,organiss10 #agea1 xiv4 #hd 8,considrations ,philosophiques sur la gradation naturelle des formes de l'tre2 ou les essais de la nature qui apprend faire l'homme10 #agfh4 #he 8,recherches sur les causes des principaux faits physiques10 par ,j4 ,b4 ,lamarck4 ,paris4 ,seconde anne de la ,rpublique4 ,in the preface1 ,lamarck says that the work was written in #aggf1 and presented to the ,academy in #aghj2 but it was not published before #agid1 and1 at that time1 it presumably expressed ,lamarck's mature views4 ,it would be interesting to know what brought about the change of opinion manifested in the 8,recherches sur l'organisation des corps vivants10 published only seven years later4 #hf ,see the 8,historical ,sketch0 prefixed to the last edition of the 8,origin of ,species40 #hg 8,first ,principles0 and 8,principles of ,biology10 #ahfj-ahfd4 #hh 8,generelle ,morphologie10 #ahff4 #hi 8,il s'agit donc de prouver que la srie qui constitute l'chelle animale rside essentiellement dans la distribution des masses principales qui la composent et non dans celle des espces ni mme toujours dans celle des genres40--8,phil4 ,zoologique10 chap4 v4 #ij ,philosophie ,zoologique1 premire partie1 chap4 iii4 #ia 8,entwurf einer ,darstellung der zwischen dem ,embryozustande der hheren ,thiere und dem permanenten der niederen stattfindenden ,parallele10 8,beytrge zur ,vergleichenden ,anatomie10 ,bd4 ii4 #ahaa4 #ib 8,origin of ,species10 ed4 #a1 p4 #deg4 #ic ,ibid4 p4 #deh4 #id 8,origin of the ,species10 p4 #dca4 #ie 8,origin of ,species10 ed4 #a1 p4 #dfc4 #if 8,discours de la ,mthode10 #f;e partie1 ,ed4 ,cousin1 p4 #aic4 #ig ,ibid4 pp4 #aic and #baa4 #ih 8,de la ,formation du ,ftus40 #ii 8,theoria ,generationis10 #agei4 #ajj 8,anatomie gnrale10 i4 p4 liv4 ,,the ,,end4 ,printed by ,r4 ,r4 ,,clark1 ,edinburgh4 ,,messrs4 ,,macmillan ,,co4',s ,,publications4 ,,by ,,the ,,same ,,author4 ,lay ,sermons1 ,addresses1 and ,reviews4 ,eighth ,edition4 #hvo4 #gs4 #f;d4 ,,contents3--,the ,advisableness of improving ,natural ,knowledge--,emancipation1 ,black and ,white--,a ,liberal ,education1 and where to find it--,scientific ,education--,on the ,study of ,zoology--,on the ,physical ,basis of ,life--,the ,scientific ,aspects of ,positivism--,on a ,piece of ,chalk1 the ,origin of ,species1 etc4 ,essays selected from ,lay ,sermons1 ,addresses1 and ,reviews4 ,third ,edition4 ,crown #hvo4 #as4 ,critiques and ,addresses4 #hvo4 #ajs4 #f;d4 ,,contents3--,administrative ,nihilism--,the ,school ,boards3 what they can do1 and what they may do--,on ,medical ,education--,yeast--,on the ,formation of ,coal--,on ,coral and ,coral ,reefs--,on the ,methods and ,results of ,ethnology--,on some ,fixed ,points in ,british ,ethnology--,palontology and the ,doctrine of ,evolution--,biogenesis and ,abiogenesis--,mr4 ,darwin's ,critics--,the ,genealogy of ,animals--,bishop ,berkeley on the ,metaphysics of ,sensation1 etc4 ,american ,addresses1 with a ,lecture on the ,study of ,biology4 #hvo4 #fs4 #f;d4 ,,contents3--,three ,lectures on ,evolution3 ,i4 ,the ,three ,hypotheses respecting the ,history of ,nature2 ,,ii4 ,the ,hypothesis of ,evolution1 the ,neutral and the ,favourable ,evidence2 ,,iii4 ,the ,demonstrative ,evidence of ,evolution--,an ,address on the occasion of the ,opening of the ,johns ,hopkins ,university--,on the ,study of ,biology1 etc4 ,physiography4 ,an ,introduction to the ,study of ,nature4 ,with ,coloured ,plates and ,woodcuts4 ,new and ,cheaper ,edition4 ,crown #hvo4 #fs4 7,thirty-third ,thousand47 8,it would hardly be possible to place a more useful or suggestive book in the hands of learners and teachers1 or one that is better calculated to make physiography a favourite subject in the ,science ,schools40--,academy4 8,it is not too much to say that any one who will read through this little volume will have a clearer and more connected idea of the physical phenomena of the earth than could be obtained by the perusal of many elaborate treatises40--,the ,guardian4 ,lessons in ,elementary ,physiology4 ,with numerous ,illustrations4 ,new ,edition4 ,fcap4 #hvo4 #ds4 #f;d4 ,introductory ,primer4 #ahmo4 #as4 7,macmillan's ,science ,primers47 ,hume4 ,crown #hvo4 ,paper ,covers1 #as42 ,cloth1 #as4 #f;d4 7,english ,men of ,letters47 8,it may fairly be said that no one now living could have expounded ,hume with more sympathy or with equal perspicuity40--,athenum4 ,a ,course of ,practical ,instruction in ,elementary ,biology4 ,by ,t4 ,h4 ,,huxley1 ,f4,r4,s41 ,,ll4,d41 assisted by ,h4 ,n4 ,,martin1 ,m4,a41 ,m4,b41 ,d4,sc41 ,f4,r4,s41 ,fellow of ,christ's ,college1 ,cambridge4 ,new ,edition1 revised and extended by ,g4 ,b4 ,,howes1 ,assistant ,professor of ,zoology1 ,normal ,school of ,science1 and ,royal ,school of ,mines2 and ,d4 ,h4 ,,scott1 ,m4,a41 ,ph4,d41 ,assistant ,professor of ,botany1 ,normal ,school of ,science1 and ,royal ,school of ,mines4 ,new ,edition1 thoroughly revised4 ,with a ,preface by ,t4 ,h4 ,,huxley1 ,f4,r4,s4 ,crown #hvo4 #ajs4 #f;d4 ,,by ,,professor ,,clifford1 ,f4,r4,s41 ,,etc4 ,lectures and ,essays4 ,by the late ,professor ,w4 ,k4 ,,clifford1 ,f4,r4,s4 ,edited by ,,leslie ,,stephen and ,,frederick ,,pollock1 with ,introduction by ,f4 ,,pollock4 ,with ,portraits4 ,two vols4 #hvo4 #bes4 ,popular ,edition4 ,crown #hvo4 #hs4 #f;d4 ,mathematical ,papers4 ,edited by ,,robert ,,tucker4 ,with an ,introduction by ,h4 ,j4 ,,stephen ,,smith1 ,m4,a41 ,,ll4,d41 ,f4,r4,s41 etc4 ,demy #hvo4 #cjs4 ,seeing and ,thinking4 ,with ,diagrams4 ,crown #hvo4 #cs4 #f;d4 7,nature ,series47 ,,by ,,professor ,p4 ,g4 ,,tait4 ,lectures on some ,recent ,advances in ,physical ,science4 ,with ,illustrations4 ,second ,edition4 ,revised and enlarged1 with the ,lecture on ,force1 delivered before the ,british ,association4 ,crown #hvo4 #is4 ,,by ,,alfred ,,russel ,,wallace4 ,the ,malay ,archipelago3 ,the ,land of the ,orang ,utan and the ,bird of ,paradise4 ,a ,narrative of ,travel4 ,with ,studies of ,man and ,nature4 ,with ,maps and ,illustrations4 ,ninth ,edition4 ,crown #hvo4 #gs4 #f;d4 ,contributions to the ,theory of ,natural ,selection4 ,a ,series of ,essays4 ,new ,edition4 ,crown #hvo4 #hs4 #f;d4 ,the ,geographical ,distribution of ,animals1 with a ,study of the ,relations of ,living and ,extinct ,faunas as elucidating the past changes of the ,earth's ,surface4 ,with numerous ,illustrations by ,,zwecker1 and ,maps4 ,two vols4 ,medium #hvo4 #dbs4 ,tropical ,nature2 and other ,essays4 #hvo4 #abs4 ,island ,life2 or1 ,the ,phenomena and ,causes of ,insular ,faunas and ,floras1 including a revision and attempted solution of the ,problem of ,geological ,climates4 ,with ,illustrations and ,maps4 ,demy #hvo4 #ahs4 ,,by ,,sir ,,john ,,lubbock1 ,,bart41 ,m4,p41 ,f4,r4,s41 ,d4,c4,l4 ,fifty ,years of ,science4 ,being the ,presidential ,address delivered at ,york to the ,british ,association1 #ahha4 #hvo4 #bs4 #f;d4 ,the ,origin and ,metamorphoses of ,insects4 ,with ,illustrations4 ,new ,edition4 ,crown #hvo4 #cs4 #f;d4 7,nature ,series47 ,on ,british ,wild ,flowers considered in their ,relation to ,insects4 ,with ,illustrations4 ,new ,edition4 ,cr4 #hvo4 #ds4 #f;d4 7,nature ,series47 ,flowers1 ,fruits1 and ,leaves4 ,with ,illustrations4 ,crown #hvo4 #ds4 #f;d4 7,nature ,series47 ,scientific ,lectures4 ,with ,illustrations4 #hvo4 #hs4 #f;d4 ,political and ,educational ,addresses4 #hvo4 #hs4 #f;d4 ,,by ,,professor ,,boyd ,,dawkins1 ,f4,r4,s41 ,,etc4 ,cave-,hunting3 ,researches on the ,evidence of ,caves respecting the ,early ,inhabitants of ,europe4 ,with ,coloured ,plate and ,woodcuts4 #hvo4 #bas4 ,early ,man in ,britain1 and his ,place in the ,tertiary ,period4 ,with ,illustrations4 #hvo4 #bes4 ,,macmillan ,,co41 ,,london1 ,w4,c4