,,theaetetus  ,by ,plato   ,translated  
by ,benjamin ,jowett     ,,introduction 
,,and ,,analysis4  ,some dialogues of   
,plato are of so various a character    
that their relation to the other        
dialogues cannot be determined with any 
degree of certainty4 ,the ,theaetetus1  
like the ,parmenides1 has points of     
similarity both with his earlier and his
 later writings4 ,the perfection of     
style1 the humour1 the dramatic         
interest1 the complexity of structure1  
the fertility of illustration1 the      
shifting of the points of view1 are     
characteristic of his best period of    
authorship4 ,the vain search1 the       
negative conclusion1 the figure of the  
midwives1 the constant profession of    
ignorance on the part of ,socrates1 also
 bear the stamp of the early dialogues1 
in which the original ,socrates is not  
yet ,platonized4 ,had we no other       
indications1 we should be disposed to   
range the ,theaetetus with the ,apology 
and the ,phaedrus1 and perhaps even with

 the ,protagoras and the ,laches4  ,but 
when we pass from the style to an       
examination of the subject1 we trace a  
connection with the later rather than   
with the earlier dialogues4 ,in the     
first place there is the connexion1     
indicated by ,plato himself at the end  
of the dialogue1 with the ,sophist1 to  
which in many respects the ,theaetetus  
is so little akin4 7#a7 ,the same       
persons reappear1 including the younger 
,socrates1 whose name is just mentioned 
in the ,theaetetus2 7#b7 the theory of  
rest1 which ,socrates has declined to   
consider1 is resumed by the ,eleatic    
,stranger2 7#c7 there is a similar      
allusion in both dialogues to the       
meeting of ,parmenides and ,socrates    
7,theaet41 ,soph472 and 7#d7 the inquiry
 into not-being in the ,sophist         
supplements the question of false       
opinion which is raised in the          
,theaetetus4 7,compare also ,theaet4 and
 ,soph4 for parallel turns of thought47 
,secondly1 the later date of the        

dialogue is confirmed by the absence of 
the doctrine of recollection and of any 
doctrine of ideas except that which     
derives them from generalization and    
from reflection of the mind upon itself4
 ,the general character of the          
,theaetetus is dialectical1 and there   
are traces of the same ,megarian        
influences which appear in the          
,parmenides1 and which later writers1 in
 their matter of fact way1 have         
explained by the residence of ,plato at 
,megara4 ,socrates disclaims the        
character of a professional eristic1 and
 also1 with a sort of ironical          
admiration1 expresses his inability to  
attain the ,megarian precision in the   
use of terms4 ,yet he too employs a     
similar sophistical skill in overturning
 every conceivable theory of knowledge4 
,the direct indications of a date amount
 to no more than this3 the conversation 
is said to have taken place when        
,theaetetus was a youth1 and shortly    
before the death of ,socrates4 ,at the  

time of his own death he is supposed to 
be a full-grown man4 ,allowing nine or  
ten years for the interval between youth
 and manhood1 the dialogue could not    
have been written earlier than #cij1    
when ,plato was about thirty-nine years 
of age4 ,no more definite date is       
indicated by the engagement in which    
,theaetetus is said to have fallen or to
 have been wounded1 and which may have  
taken place any time during the         
,corinthian war1 between the years      
#cij-chg4 ,the later date which has been
 suggested1 #cfi1 when the ,athenians   
and ,lacedaemonians disputed the        
,isthmus with ,epaminondas1 would make  
the age of ,theaetetus at his death     
forty-five or forty-six4 ,this a little 
impairs the beauty of ,socrates' remark1
 that 'he would be a great man if he    
lived4'  ,in this uncertainty about the 
place of the ,theaetetus1 it seemed     
better1 as in the case of the ,republic1
 ,timaeus1 ,critias1 to retain the order
 in which ,plato himself has arranged   

this and the two companion dialogues4   
,we cannot exclude the possibility which
 has been already noticed in reference  
to other works of ,plato1 that the      
,theaetetus may not have been all       
written continuously2 or the probability
 that the ,sophist and ,politicus1 which
 differ greatly in style1 were only     
appended after a long interval of time4 
,the allusion to ,parmenides compared   
with the ,sophist1 would probably imply 
that the dialogue which is called by his
 name was already in existence2 unless1 
indeed1 we suppose the passage in which 
the allusion occurs to have been        
inserted afterwards4 ,again1 the        
,theaetetus may be connected with the   
,gorgias1 either dialogue from different
 points of view containing an analysis  
of the real and apparent                
7,schleiermacher72 and both may be      
brought into relation with the ,apology 
as illustrating the personal life of    
,socrates4 ,the ,philebus1 too1 may with
 equal reason be placed either after or 

before what1 in the language of         
,thrasyllus1 may be called the ,second  
,platonic ,trilogy4 ,both the           
,parmenides and the ,sophist1 and still 
more the ,theaetetus1 have points of    
affinity with the ,cratylus1 in which   
the principles of rest and motion are   
again contrasted1 and the ,sophistical  
or ,protagorean theory of language is   
opposed to that which is attributed to  
the disciple of ,heracleitus1 not to    
speak of lesser resemblances in thought 
and language4 ,the ,parmenides1 again1  
has been thought by some to hold an     
intermediate position between the       
,theaetetus and the ,sophist2 upon this 
view1 the ,sophist may be regarded as   
the answer to the problems about ,one   
and ,being which have been raised in the
 ,parmenides4 ,any of these arrangements
 may suggest new views to the student of
 ,plato2 none of them can lay claim to  
an exclusive probability in its favour4 
,the ,theaetetus is one of the narrated 
dialogues of ,plato1 and is the only one

 which is supposed to have been written 
down4 ,in a short introductory scene1   
,euclides and ,terpsion are described as
 meeting before the door of ,euclides'  
house in ,megara4 ,this may have been a 
spot familiar to ,plato 7for ,megara was
 within a walk of ,athens71 but no      
importance can be attached to the       
accidental introduction of the founder  
of the ,megarian philosophy4 ,the real  
intention of the preface is to create an
 interest about the person of           
,theaetetus1 who has just been carried  
up from the army at ,corinth in a dying 
state4 ,the expectation of his death    
recalls the promise of his youth1 and   
especially the famous conversation which
 ,socrates had with him when he was     
quite young1 a few days before his own  
trial and death1 as we are once more    
reminded at the end of the dialogue4    
,yet we may observe that ,plato has     
himself forgotten this1 when he         
represents ,euclides as from time to    
time coming to ,athens and correcting   

the copy from ,socrates' own mouth4 ,the
 narrative1 having introduced           
,theaetetus1 and having guaranteed the  
authenticity of the dialogue 7compare   
,symposium1 ,phaedo1 ,parmenides71 is   
then dropped4 ,no further use is made of
 the device4 ,as ,plato himself remarks1
 who in this as in some other minute    
points is imitated by ,cicero 7,de      
,amicitia71 the interlocutory words are 
omitted4  ,theaetetus1 the hero of the  
battle of ,corinth and of the dialogue1 
is a disciple of ,theodorus1 the great  
geometrician1 whose science is thus     
indicated to be the propaedeutic to     
philosophy4 ,an interest has been       
already excited about him by his        
approaching death1 and now he is        
introduced to us anew by the praises of 
his master ,theodorus4 ,he is a youthful
 ,socrates1 and exhibits the same       
contrast of the fair soul and the       
ungainly face and frame1 the ,silenus   
mask and the god within1 which are      
described in the ,symposium4 ,the       

picture which ,theodorus gives of his   
courage and patience and intelligence   
and modesty is verified in the course of
 the dialogue4 ,his courage is shown by 
his behaviour in the battle1 and his    
other qualities shine forth as the      
argument proceeds4 ,socrates takes an   
evident delight in 'the wise            
,theaetetus1' who has more in him than  
'many bearded men'2 he is quite inspired
 by his answers4 ,at first the youth is 
lost in wonder1 and is almost too modest
 to speak1 but1 encouraged by ,socrates1
 he rises to the occasion1 and grows    
full of interest and enthusiasm about   
the great question4 ,like a youth1 he   
has not finally made up his mind1 and is
 very ready to follow the lead of       
,socrates1 and to enter into each       
successive phase of the discussion which
 turns up4 ,his great dialectical talent
 is shown in his power of drawing       
distinctions1 and of foreseeing the     
consequences of his own answers4 ,the   
enquiry about the nature of knowledge is

 not new to him2 long ago he has felt   
the 'pang of philosophy1' and has       
experienced the youthful intoxication   
which is depicted in the ,philebus4 ,but
 he has hitherto been unable to make the
 transition from mathematics to         
metaphysics4 ,he can form a general     
conception of square and oblong numbers1
 but he is unable to attain a similar   
expression of knowledge in the abstract4
 ,yet at length he begins to recognize  
that there are universal conceptions of 
being1 likeness1 sameness1 number1 which
 the mind contemplates in herself1 and  
with the help of ,socrates is conducted 
from a theory of sense to a theory of   
ideas4  ,there is no reason to doubt    
that ,theaetetus was a real person1     
whose name survived in the next         
generation4 ,but neither can any        
importance be attached to the notices of
 him in ,suidas and ,proclus1 which are 
probably based on the mention of him in 
,plato4 ,according to a confused        
statement in ,suidas1 who mentions him  

twice over1 first1 as a pupil of        
,socrates1 and then of ,plato1 he is    
said to have written the first work on  
the ,five ,solids4 ,but no early        
authority cites the work1 the invention 
of which may have been easily suggested 
by the division of roots1 which ,plato  
attributes to him1 and the allusion to  
the backward state of solid geometry in 
the ,republic4 ,at any rate1 there is no
 occasion to recall him to life again   
after the battle of ,corinth1 in order  
that we may allow time for the          
completion of such a work 7,muller74 ,we
 may also remark that such a supposition
 entirely destroys the pathetic interest
 of the introduction4  ,theodorus1 the  
geometrician1 had once been the friend  
and disciple of ,protagoras1 but he is  
very reluctant to leave his retirement  
and defend his old master4 ,he is too   
old to learn ,socrates' game of question
 and answer1 and prefers the digressions
 to the main argument1 because he finds 
them easier to follow4 ,the             

mathematician1 as ,socrates says in the 
,republic1 is not capable of giving a   
reason in the same manner as the        
dialectician1 and ,theodorus could not  
therefore have been appropriately       
introduced as the chief respondent4 ,but
 he may be fairly appealed to1 when the 
honour of his master is at stake4 ,he is
 the 'guardian of his orphans1' although
 this is a responsibility which he      
wishes to throw upon ,callias1 the      
friend and patron of all ,sophists1     
declaring that he himself had early 'run
 away' from philosophy1 and was absorbed
 in mathematics4 ,his extreme dislike to
 the ,heraclitean fanatics1 which may be
 compared with the dislike of           
,theaetetus to the materialists1 and his
 ready acceptance of the noble words of 
,socrates1 are noticeable traits of     
character4  ,the ,socrates of the       
,theaetetus is the same as the ,socrates
 of the earlier dialogues4 ,he is the   
invincible disputant1 now advanced in   
years1 of the ,protagoras and           

,symposium2 he is still pursuing his    
divine mission1 his ',herculean         
labours1' of which he has described the 
origin in the ,apology2 and he still    
hears the voice of his oracle1 bidding  
him receive or not receive the truant   
souls4 ,there he is supposed to have a  
mission to convict men of self-conceit2 
in the ,theaetetus he has assigned to   
him by ,god the functions of a          
man-midwife1 who delivers men of their  
thoughts1 and under this character he is
 present throughout the dialogue4 ,he is
 the true prophet who has an insight    
into the natures of men1 and can divine 
their future2 and he knows that sympathy
 is the secret power which unlocks their
 thoughts4 ,the hit at ,aristides1 the  
son of ,lysimachus1 who was specially   
committed to his charge in the ,laches1 
may be remarked by the way4 ,the attempt
 to discover the definition of knowledge
 is in accordance with the character of 
,socrates as he is described in the     
,memorabilia1 asking ,what is justice8  

what is temperance8 and the like4 ,but  
there is no reason to suppose that he   
would have analyzed the nature of       
perception1 or traced the connexion of  
,protagoras and ,heracleitus1 or have   
raised the difficulty respecting false  
opinion4 ,the humorous illustrations1 as
 well as the serious thoughts1 run      
through the dialogue4 ,the snubnosedness
 of ,theaetetus1 a characteristic which 
he shares with ,socrates1 and the       
man-midwifery of ,socrates1 are not     
forgotten in the closing words4 ,at the 
end of the dialogue1 as in the          
,euthyphro1 he is expecting to meet     
,meletus at the porch of the king       
,archon2 but with the same indifference 
to the result which is everywhere       
displayed by him1 he proposes that they 
shall reassemble on the following day at
 the same spot4 ,the day comes1 and in  
the ,sophist the three friends again    
meet1 but no further allusion is made to
 the trial1 and the principal share in  
the argument is assigned1 not to        

,socrates1 but to an ,eleatic stranger2 
the youthful ,theaetetus also plays a   
different and less independent part4    
,and there is no allusion in the        
,introduction to the second and third   
dialogues1 which are afterwards         
appended4 ,there seems1 therefore1      
reason to think that there is a real    
change1 both in the characters and in   
the design4  ,the dialogue is an enquiry
 into the nature of knowledge1 which is 
interrupted by two digressions4 ,the    
first is the digression about the       
midwives1 which is also a leading       
thought or continuous image1 like the   
wave in the ,republic1 appearing and    
reappearing at intervals4 ,again and    
again we are reminded that the          
successive conceptions of knowledge are 
extracted from ,theaetetus1 who in his  
turn truly declares that ,socrates has  
got a great deal more out of him than   
ever was in him4 ,socrates is never     
weary of working out the image in       
humorous details1--discerning the       

symptoms of labour1 carrying the child  
round the hearth1 fearing that          
,theaetetus will bite him1 comparing his
 conceptions to wind-eggs1 asserting an 
hereditary right to the occupation4     
,there is also a serious side to the    
image1 which is an apt similitude of the
 ,socratic theory of education 7compare 
,republic1 ,sophist71 and accords with  
the ironical spirit in which the wisest 
of men delights to speak of himself4    
,the other digression is the famous     
contrast of the lawyer and philosopher4 
,this is a sort of landing-place or     
break in the middle of the dialogue4 ,at
 the commencement of a great discussion1
 the reflection naturally arises1 ,how  
happy are they who1 like the            
philosopher1 have time for such         
discussions 7compare ,republic76 ,there 
is no reason for the introduction of    
such a digression2 nor is a reason      
always needed1 any more than for the    
introduction of an episode in a poem1 or
 of a topic in conversation4 ,that which

 is given by ,socrates is quite         
sufficient1 viz4 that the philosopher   
may talk and write as he pleases4 ,but  
though not very closely connected1      
neither is the digression out of keeping
 with the rest of the dialogue4 ,the    
philosopher naturally desires to pour   
forth the thoughts which are always     
present to him1 and to discourse of the 
higher life4 ,the idea of knowledge1    
although hard to be defined1 is realised
 in the life of philosophy4 ,and the    
contrast is the favourite antithesis    
between the world1 in the various       
characters of sophist1 lawyer1          
statesman1 speaker1 and the             
philosopher1--between opinion and       
knowledge1--between the conventional and
 the true4  ,the greater part of the    
dialogue is devoted to setting up and   
throwing down definitions of science and
 knowledge4 ,proceeding from the lower  
to the higher by three stages1 in which 
perception1 opinion1 reasoning are      
successively examined1 we first get rid 

of the confusion of the idea of         
knowledge and specific kinds of         
knowledge1--a confusion which has been  
already noticed in the ,lysis1 ,laches1 
,meno1 and other dialogues4 ,in the     
infancy of logic1 a form of thought has 
to be invented before the content can be
 filled up4 ,we cannot define knowledge 
until the nature of definition has been 
ascertained4 ,having succeeded in making
 his meaning plain1 ,socrates proceeds  
to analyze 7#a7 the first definition    
which ,theaetetus proposes3 ',knowledge 
is sensible perception4' ,this is       
speedily identified with the            
,protagorean saying1 ',man is the       
measure of all things2' and of this     
again the foundation is discovered in   
the perpetual flux of ,heracleitus4 ,the
 relativeness of sensation is then      
developed at length1 and for a moment   
the definition appears to be accepted4  
,but soon the ,protagorean thesis is    
pronounced to be suicidal2 for the      
adversaries of ,protagoras are as good a

 measure as he is1 and they deny his    
doctrine4 ,he is then supposed to reply 
that the perception may be true at any  
given instant4 ,but the reply is in the 
end shown to be inconsistent with the   
,heraclitean foundation1 on which the   
doctrine has been affirmed to rest4 ,for
 if the ,heraclitean flux is extended to
 every sort of change in every instant  
of time1 how can any thought or word be 
detained even for an instant8 ,sensible 
perception1 like everything else1 is    
tumbling to pieces4 ,nor can ,protagoras
 himself maintain that one man is as    
good as another in his knowledge of the 
future2 and 'the expedient1' if not 'the
 just and true1' belongs to the sphere  
of the future4  ,and so we must ask     
again1 ,what is knowledge8 ,the         
comparison of sensations with one       
another implies a principle which is    
above sensation1 and which resides in   
the mind itself4 ,we are thus led to    
look for knowledge in a higher sphere1  
and accordingly ,theaetetus1 when again 

interrogated1 replies 7#b7 that         
'knowledge is true opinion4' ,but how is
 false opinion possible8 ,the ,megarian 
or ,eristic spirit within us revives the
 question1 which has been already asked 
and indirectly answered in the ,meno3   
',how can a man be ignorant of that     
which he knows8' ,no answer is given to 
this not unanswerable question4 ,the    
comparison of the mind to a block of    
wax1 or to a decoy of birds1 is found   
wanting4  ,but are we not inverting the 
natural order in looking for opinion    
before we have found knowledge8 ,and    
knowledge is not true opinion2 for the  
,athenian dicasts have true opinion but 
not knowledge4 ,what then is knowledge8 
,we answer 7#c71 ',true opinion1 with   
definition or explanation4' ,but all the
 different ways in which this statement 
may be understood are set aside1 like   
the definitions of courage in the       
,laches1 or of friendship in the ,lysis1
 or of temperance in the ,charmides4 ,at
 length we arrive at the conclusion1 in 

which nothing is concluded4  ,there are 
two special difficulties which beset the
 student of the ,theaetetus3 7#a7 he is 
uncertain how far he can trust ,plato's 
account of the theory of ,protagoras2   
and he is also uncertain 7#b7 how far1  
and in what parts of the dialogue1      
,plato is expressing his own opinion4   
,the dramatic character of the work     
renders the answer to both these        
questions difficult4  #a4 ,in reply to  
the first1 we have only probabilities to
 offer4 ,three main points have to be   
decided3 7a7 ,would ,protagoras have    
identified his own thesis1 ',man is the 
measure of all things1' with the other1 
',all knowledge is sensible perception'8
 7b7 ,would he have based the relativity
 of knowledge on the ,heraclitean flux8 
7c7 ,would he have asserted the         
absoluteness of sensation at each       
instant8 ,of the work of ,protagoras on 
',truth' we know nothing1 with the      
exception of the two famous fragments1  
which are cited in this dialogue1 ',man 

is the measure of all things1' and1     
',whether there are gods or not1 ,i     
cannot tell4' ,nor have we any other    
trustworthy evidence of the tenets of   
,protagoras1 or of the sense in which   
his words are used4 ,for later writers1 
including ,aristotle in his             
,metaphysics1 have mixed up the         
,protagoras of ,plato1 as they have the 
,socrates of ,plato1 with the real      
person4  ,returning then to the         
,theaetetus1 as the only possible source
 from which an answer to these questions
 can be obtained1 we may remark1 that   
,plato had ',the ,truth' of ,protagoras 
before him1 and frequently refers to the
 book4 ,he seems to say expressly1 that 
in this work the doctrine of the        
,heraclitean flux was not to be found2  
'he told the real truth' 7not in the    
book1 which is so entitled1 but7        
'privately to his disciples1'--words    
which imply that the connexion between  
the doctrines of ,protagoras and        
,heracleitus was not generally          

recognized in ,greece1 but was really   
discovered or invented by ,plato4 ,on   
the other hand1 the doctrine that ',man 
is the measure of all things1' is       
expressly identified by ,socrates with  
the other statement1 that ',what appears
 to each man is to him2' and a reference
 is made to the books in which the      
statement occurs2--this ,theaetetus1 who
 has 'often read the books1' is supposed
 to acknowledge 7so ,cratylus74 ,and    
,protagoras1 in the speech attributed to
 him1 never says that he has been       
misunderstood3 he rather seems to imply 
that the absoluteness of sensation at   
each instant was to be found in his     
words4 ,he is only indignant at the     
'reductio ad absurdum' devised by       
,socrates for his 'homo mensura1' which 
,theodorus also considers to be 'really 
too bad4'  ,the question may be raised1 
how far ,plato in the ,theaetetus could 
have misrepresented ,protagoras without 
violating the laws of dramatic          
probability4 ,could he have pretended to

 cite from a well-known writing what was
 not to be found there8 ,but such a     
shadowy enquiry is not worth pursuing   
further4 ,we need only remember that in 
the criticism which follows of the      
thesis of ,protagoras1 we are           
criticizing the ,protagoras of ,plato1  
and not attempting to draw a precise    
line between his real sentiments and    
those which ,plato has attributed to    
him4  #b4 ,the other difficulty is a    
more subtle1 and also a more important  
one1 because bearing on the general     
character of the ,platonic dialogues4   
,on a first reading of them1 we are apt 
to imagine that the truth is only spoken
 by ,socrates1 who is never guilty of a 
fallacy himself1 and is the great       
detector of the errors and fallacies of 
others4 ,but this natural presumption is
 disturbed by the discovery that the    
,sophists are sometimes in the right and
 ,socrates in the wrong4 ,like the hero 
of a novel1 he is not to be supposed    
always to represent the sentiments of   

the author4 ,there are few modern       
readers who do not side with            
,protagoras1 rather than with ,socrates1
 in the dialogue which is called by his 
name4 ,the ,cratylus presents a similar 
difficulty3 in his etymologies1 as in   
the number of the ,state1 we cannot tell
 how far ,socrates is serious2 for the  
,socratic irony will not allow him to   
distinguish between his real and his    
assumed wisdom4 ,no one is the superior 
of the invincible ,socrates in argument 
7except in the first part of the        
,parmenides1 where he is introduced as a
 youth72 but he is by no means supposed 
to be in possession of the whole truth4 
,arguments are often put into his mouth 
7compare ,introduction to the ,gorgias7 
which must have seemed quite as         
untenable to ,plato as to a modern      
writer4 ,in this dialogue a great part  
of the answer of ,protagoras is just and
 sound2 remarks are made by him on      
verbal criticism1 and on the importance 
of understanding an opponent's meaning1 

which are conceived in the true spirit  
of philosophy4 ,and the distinction     
which he is supposed to draw between    
,eristic and ,dialectic1 is really a    
criticism of ,plato on himself and his  
own criticism of ,protagoras4  ,the     
difficulty seems to arise from not      
attending to the dramatic character of  
the writings of ,plato4 ,there are two1 
or more1 sides to questions2 and these  
are parted among the different speakers4
 ,sometimes one view or aspect of a     
question is made to predominate over the
 rest1 as in the ,gorgias or ,sophist2  
but in other dialogues truth is divided1
 as in the ,laches and ,protagoras1 and 
the interest of the piece consists in   
the contrast of opinions4 ,the confusion
 caused by the irony of ,socrates1 who1 
if he is true to his character1 cannot  
say anything of his own knowledge1 is   
increased by the circumstance that in   
the ,theaetetus and some other dialogues
 he is occasionally playing both parts  
himself1 and even charging his own      

arguments with unfairness4 ,in the      
,theaetetus he is designedly held back  
from arriving at a conclusion4 ,for we  
cannot suppose that ,plato conceived a  
definition of knowledge to be           
impossible4 ,but this is his manner of  
approaching and surrounding a question4 
,the lights which he throws on his      
subject are indirect1 but they are not  
the less real for that4 ,he has no      
intention of proving a thesis by a      
cut-and-dried argument2 nor does he     
imagine that a great philosophical      
problem can be tied up within the limits
 of a definition4 ,if he has analyzed a 
proposition or notion1 even with the    
severity of an impossible logic1 if     
half-truths have been compared by him   
with other half-truths1 if he has       
cleared up or advanced popular ideas1 or
 illustrated a new method1 his aim has  
been sufficiently accomplished4  ,the   
writings of ,plato belong to an age in  
which the power of analysis had outrun  
the means of knowledge2 and through a   

spurious use of dialectic1 the          
distinctions which had been already 'won
 from the void and formless infinite1'  
seemed to be rapidly returning to their 
original chaos4 ,the two great          
speculative philosophies1 which a       
century earlier had so deeply impressed 
the mind of ,hellas1 were now           
degenerating into ,eristic4 ,the        
contemporaries of ,plato and ,socrates  
were vainly trying to find new          
combinations of them1 or to transfer    
them from the object to the subject4    
,the ,megarians1 in their first attempts
 to attain a severer logic1 were making 
knowledge impossible 7compare ,theaet474
 ,they were asserting 'the one good     
under many names1' and1 like the        
,cynics1 seem to have denied            
predication1 while the ,cynics          
themselves were depriving virtue of all 
which made virtue desirable in the eyes 
of ,socrates and ,plato4 ,and besides   
these1 we find mention in the later     
writings of ,plato1 especially in the   

,theaetetus1 ,sophist1 and ,laws1 of    
certain impenetrable godless persons1   
who will not believe what they 'cannot  
hold in their hands'2 and cannot be     
approached in argument1 because they    
cannot argue 7,theat2 ,soph474 ,no      
school of ,greek philosophers exactly   
answers to these persons1 in whom ,plato
 may perhaps have blended some features 
of the ,atomists with the vulgar        
materialistic tendencies of mankind in  
general 7compare ,introduction to the   
,sophist74  ,and not only was there a   
conflict of opinions1 but the stage     
which the mind had reached presented    
other difficulties hardly intelligible  
to us1 who live in a different cycle of 
human thought4 ,all times of mental     
progress are times of confusion2 we only
 see1 or rather seem to see things      
clearly1 when they have been long fixed 
and defined4 ,in the age of ,plato1 the 
limits of the world of imagination and  
of pure abstraction1 of the old world   
and the new1 were not yet fixed4 ,the   

,greeks1 in the fourth century before   
,christ1 had no words for 'subject' and 
'object1' and no distinct conception of 
them2 yet they were always hovering     
about the question involved in them4    
,the analysis of sense1 and the analysis
 of thought1 were equally difficult to  
them2 and hopelessly confused by the    
attempt to solve them1 not through an   
appeal to facts1 but by the help of     
general theories respecting the nature  
of the universe4  ,plato1 in his        
,theaetetus1 gathers up the sceptical   
tendencies of his age1 and compares     
them4 ,but he does not seek to          
reconstruct out of them a theory of     
knowledge4 ,the time at which such a    
theory could be framed had not yet      
arrived4 ,for there was no measure of   
experience with which the ideas swarming
 in men's minds could be compared2 the  
meaning of the word 'science' could     
scarcely be explained to them1 except   
from the mathematical sciences1 which   
alone offered the type of universality  

and certainty4 ,philosophy was becoming 
more and more vacant and abstract1 and  
not only the ,platonic ,ideas and the   
,eleatic ,being1 but all abstractions   
seemed to be at variance with sense and 
at war with one another4  ,the want of  
the ,greek mind in the fourth century   
before ,christ was not another theory of
 rest or motion1 or ,being or atoms1 but
 rather a philosophy which could free   
the mind from the power of abstractions 
and alternatives1 and show how far rest 
and how far motion1 how far the         
universal principle of ,being and the   
multitudinous principle of atoms1       
entered into the composition of the     
world2 which could distinguish between  
the true and false analogy1 and allow   
the negative as well as the positive a  
place in human thought4 ,to such a      
philosophy ,plato1 in the ,theaetetus1  
offers many contributions4 ,he has      
followed philosophy into the region of  
mythology1 and pointed out the          
similarities of opposing phases of      

thought4 ,he has also shown that extreme
 abstractions are self-destructive1 and1
 indeed1 hardly distinguishable from one
 another4 ,but his intention is not to  
unravel the whole subject of knowledge1 
if this had been possible2 and several  
times in the course of the dialogue he  
rejects explanations of knowledge which 
have germs of truth in them2 as1 for    
example1 'the resolution of the compound
 into the simple2' or 'right opinion    
with a mark of difference4'  444        
,terpsion1 who has come to ,megara from 
the country1 is described as having     
looked in vain for ,euclides in the     
,agora2 the latter explains that he has 
been down to the harbour1 and on his way
 thither had met ,theaetetus1 who was   
being carried up from the army to       
,athens4 ,he was scarcely alive1 for he 
had been badly wounded at the battle of 
,corinth1 and had taken the dysentery   
which prevailed in the camp4 ,the       
mention of his condition suggests the   
reflection1 ',what a loss he will be6'  

',yes1 indeed1' replies ,euclid2 'only  
just now ,i was hearing of his noble    
conduct in the battle4' ',that ,i should
 expect2 but why did he not remain at   
,megara8' ',i wanted him to remain1 but 
he would not2 so ,i went with him as far
 as ,erineum2 and as ,i parted from him1
 ,i remembered that ,socrates had seen  
him when he was a youth1 and had a      
remarkable conversation with him1 not   
long before his own death2 and he then  
prophesied of him that he would be a    
great man if he lived4' ',how true that 
has been2 how like all that ,socrates   
said6 ,and could you repeat the         
conversation8' ',not from memory2 but ,i
 took notes when ,i returned home1 which
 ,i afterwards filled up at leisure1 and
 got ,socrates to correct them from time
 to time1 when ,i came to               
,athens'444,terpsion had long intended  
to ask for a sight of this writing1 of  
which he had already heard4 ,they are   
both tired1 and agree to rest and have  
the conversation read to them by a      

servant444',here is the roll1 ,terpsion2
 ,i need only observe that ,i have      
omitted1 for the sake of convenience1   
the interlocutory words1 said ,i1 said  
he2 and that ,theaetetus1 and           
,theodorus1 the geometrician of ,cyrene1
 are the persons with whom ,socrates is 
conversing4'  ,socrates begins by asking
 ,theodorus whether1 in his visit to    
,athens1 he has found any ,athenian     
youth likely to attain distinction in   
science4 ',yes1 ,socrates1 there is one 
very remarkable youth1 with whom ,i have
 become acquainted4 ,he is no beauty1   
and therefore you need not imagine that 
,i am in love with him2 and1 to say the 
truth1 he is very like you1 for he has a
 snub nose1 and projecting eyes1        
although these features are not so      
marked in him as in you4 ,he combines   
the most various qualities1 quickness1  
patience1 courage2 and he is gentle as  
well as wise1 always silently flowing   
on1 like a river of oil4 ,look6 he is   
the middle one of those who are entering

 the palaestra4'  ,socrates1 who does   
not know his name1 recognizes him as the
 son of ,euphronius1 who was himself a  
good man and a rich4 ,he is informed by 
,theodorus that the youth is named      
,theaetetus1 but the property of his    
father has disappeared in the hands of  
trustees2 this does not1 however1       
prevent him from adding liberality to   
his other virtues4 ,at the desire of    
,socrates he invites ,theaetetus to sit 
by them4  ',yes1' says ,socrates1 'that 
,i may see in you1 ,theaetetus1 the     
image of my ugly self1 as ,theodorus    
declares4 ,not that his remark is of any
 importance2 for though he is a         
philosopher1 he is not a painter1 and   
therefore he is no judge of our faces2  
but1 as he is a man of science1 he may  
be a judge of our intellects4 ,and if he
 were to praise the mental endowments of
 either of us1 in that case the hearer  
of the eulogy ought to examine into what
 he says1 and the subject should not    
refuse to be examined4' ,theaetetus     

consents1 and is caught in a trap       
7compare the similar trap which is laid 
for ,theodorus74 ',then1 ,theaetetus1   
you will have to be examined1 for       
,theodorus has been praising you in a   
style of which ,i never heard the like4'
 ',he was only jesting4' ',nay1 that is 
not his way2 and ,i cannot allow you1 on
 that pretence1 to retract the assent   
which you have already given1 or ,i     
shall make ,theodorus repeat your       
praises1 and swear to them4'            
,theaetetus1 in reply1 professes that he
 is willing to be examined1 and         
,socrates begins by asking him what he  
learns of ,theodorus4 ,he is himself    
anxious to learn anything of anybody2   
and now he has a little question to     
which he wants ,theaetetus or ,theodorus
 7or whichever of the company would not 
be 'donkey' to the rest7 to find an     
answer4 ,without further preface1 but at
 the same time apologizing for his      
eagerness1 he asks1 ',what is           
knowledge8' ,theodorus is too old to    

answer questions1 and begs him to       
interrogate ,theaetetus1 who has the    
advantage of youth4  ,theaetetus        
replies1 that knowledge is what he      
learns of ,theodorus1 i4e4 geometry and 
arithmetic2 and that there are other    
kinds of knowledge--shoemaking1         
carpentering1 and the like4 ,but        
,socrates rejoins1 that this answer     
contains too much and also too little4  
,for although ,theaetetus has enumerated
 several kinds of knowledge1 he has not 
explained the common nature of them2 as 
if he had been asked1 ',what is clay8'  
and instead of saying ',clay is         
moistened earth1' he had answered1      
',there is one clay of image-makers1    
another of potters1 another of          
oven-makers4' ,theaetetus at once       
divines that ,socrates means him to     
extend to all kinds of knowledge the    
same process of generalization which he 
has already learned to apply to         
arithmetic4 ,for he has discovered a    
division of numbers into square numbers1

 #d1 #i1 #af1 etc41 which are composed  
of equal factors1 and represent figures 
which have equal sides1 and oblong      
numbers1 #c1 #e1 #f1 #g1 etc41 which are
 composed of unequal factors1 and       
represent figures which have unequal    
sides4 ,but he has never succeeded in   
attaining a similar conception of       
knowledge1 though he has often tried2   
and1 when this and similar questions    
were brought to him from ,socrates1 has 
been sorely distressed by them4         
,socrates explains to him that he is in 
labour4 ,for men as well as women have  
pangs of labour2 and both at times      
require the assistance of midwives4 ,and
 he1 ,socrates1 is a midwife1 although  
this is a secret2 he has inherited the  
art from his mother bold and bluff1 and 
he ushers into light1 not children1 but 
the thoughts of men4 ,like the midwives1
 who are 'past bearing children1' he too
 can have no offspring--the ,god will   
not allow him to bring anything into the
 world of his own4 ,he also reminds     

,theaetetus that the midwives are or    
ought to be the only matchmakers 7this  
is the preparation for a biting jest72  
for those who reap the fruit are most   
likely to know on what soil the plants  
will grow4 ,but respectable midwives    
avoid this department of practice--they 
do not want to be called procuresses4   
,there are some other differences       
between the two sorts of pregnancy4 ,for
 women do not bring into the world at   
one time real children and at another   
time idols which are with difficulty    
distinguished from them4 ',at first1'   
says ,socrates in his character of the  
man-midwife1 'my patients are barren and
 stolid1 but after a while they round   
apace1 if the gods are propitious to    
them2 and this is due not to me but to  
themselves2 ,i and the god only assist  
in bringing their ideas to the birth4   
,many of them have left me too soon1 and
 the result has been that they have     
produced abortions2 or when ,i have     
delivered them of children they have    

lost them by an ill bringing up1 and    
have ended by seeing themselves1 as     
others see them1 to be great fools4     
,aristides1 the son of ,lysimachus1 is  
one of these1 and there have been       
others4 ,the truants often return to me 
and beg to be taken back2 and then1 if  
my familiar allows me1 which is not     
always the case1 ,i receive them1 and   
they begin to grow again4 ,there come to
 me also those who have nothing in them1
 and have no need of my art2 and ,i am  
their matchmaker 7see above71 and marry 
them to ,prodicus or some other inspired
 sage who is likely to suit them4 ,i    
tell you this long story because ,i     
suspect that you are in labour4 ,come   
then to me1 who am a midwife1 and the   
son of a midwife1 and ,i will deliver   
you4 ,and do not bite me1 as the women  
do1 if ,i abstract your first-born2 for 
,i am acting out of good-will towards   
you2 the ,god who is within me is the   
friend of man1 though he will not allow 
me to dissemble the truth4 ,once more   

then1 ,theaetetus1 ,i repeat my old     
question--,what is knowledge8 ,take     
courage1 and by the help of ,god you    
will discover an answer4' ',my answer   
is1 that knowledge is perception4'      
',that is the theory of ,protagoras1 who
 has another way of expressing the same 
thing when he says1 ,man is the measure 
of all things4 ,he was a very wise man1 
and we should try to understand him4 ,in
 order to illustrate his meaning let me 
suppose that there is the same wind     
blowing in our faces1 and one of us may 
be hot and the other cold4 ,how is this8
 ,protagoras will reply that the wind is
 hot to him who is cold1 cold to him who
 is hot4 ,and is means appears1 and when
 you say appears to him1 that means he  
feels4 ,thus feeling1 appearance1       
perception1 coincide with being4 ,i     
suspect1 however1 that this was only a  
facon de parler1 by which he imposed on 
the common herd like you and me2 he told
 the truth 7in allusion to the title of 
his book1 which was called ,the ,truth7 

in secret to his disciples4 ,for he was 
really a votary of that famous          
philosophy in which all things are said 
to be relative2 nothing is great or     
small1 or heavy or light1 or one1 but   
all is in motion and mixture and        
transition and flux and generation1 not 
being1 as we ignorantly affirm1 but     
becoming4 ,this has been the doctrine1  
not of ,protagoras only1 but of all     
philosophers1 with the single exception 
of ,parmenides2 ,empedocles1            
,heracleitus1 and others1 and all the   
poets1 with ,epicharmus1 the king of    
,comedy1 and ,homer1 the king of        
,tragedy1 at their head1 have said the  
same2 the latter has these words--      
,ocean1 whence the gods sprang1 and     
mother ,tethys4  ,and many arguments are
 used to show1 that motion is the source
 of life1 and rest of death3 fire and   
warmth are produced by friction1 and    
living creatures owe their origin to a  
similar cause2 the bodily frame is      
preserved by exercise and destroyed by  

indolence2 and if the sun ceased to     
move1 chaos would come again4 ,now apply
 this doctrine of ,all is motion to the 
senses1 and first of all to the sense of
 sight4 ,the colour of white1 or any    
other colour1 is neither in the eyes nor
 out of them1 but ever in motion between
 the object and the eye1 and varying in 
the case of every percipient4 ,all is   
relative1 and1 as the followers of      
,protagoras remark1 endless             
contradictions arise when we deny this2 
e4g4 here are six dice2 they are more   
than four and less than twelve2 more and
 also less1 would you not say8' ',yes4' 
',but ,protagoras will retort3 ,can     
anything be more or less without        
addition or subtraction8'  ',i should   
say ,no if ,i were not afraid of        
contradicting my former answer4'  ',and 
if you say ,yes1 the tongue will escape 
conviction but not the mind1 as         
,euripides would say8' ',true4' ',the   
thoroughbred ,sophists1 who know all    
that can be known1 would have a sparring

 match over this1 but you and ,i1 who   
have no professional pride1 want only to
 discover whether our ideas are clear   
and consistent4 ,and we cannot be wrong 
in saying1 first1 that nothing can be   
greater or less while remaining equal2  
secondly1 that there can be no becoming 
greater or less without addition or     
subtraction2 thirdly1 that what is and  
was not1 cannot be without having       
become4 ,but then how is this           
reconcilable with the case of the dice1 
and with similar examples8--that is the 
question4' ',i am often perplexed and   
amazed1 ,socrates1 by these             
difficulties4' ',that is because you are
 a philosopher1 for philosophy begins in
 wonder1 and ,iris is the child of      
,thaumas4 ,do you know the original     
principle on which the doctrine of      
,protagoras is based8' ',no4' ',then ,i 
will tell you2 but we must not let the  
uninitiated hear1 and by the uninitiated
 ,i mean the obstinate people who       
believe in nothing which they cannot    

hold in their hands4 ,the brethren whose
 mysteries ,i am about to unfold to you 
are far more ingenious4 ,they maintain  
that all is motion2 and that motion has 
two forms1 action and passion1 out of   
which endless phenomena are created1    
also in two forms--sense and the object 
of sense--which come to the birth       
together4 ,there are two kinds of       
motions1 a slow and a fast2 the motions 
of the agent and the patient are slower1
 because they move and create in and    
about themselves1 but the things which  
are born of them have a swifter motion1 
and pass rapidly from place to place4   
,the eye and the appropriate object come
 together1 and give birth to whiteness  
and the sensation of whiteness2 the eye 
is filled with seeing1 and becomes not  
sight but a seeing eye1 and the object  
is filled with whiteness1 and becomes   
not whiteness but white2 and no other   
compound of either with another would   
have produced the same effect4 ,all     
sensation is to be resolved into a      

similar combination of an agent and     
patient4 ,of either1 taken separately1  
no idea can be formed2 and the agent may
 become a patient1 and the patient an   
agent4 ,hence there arises a general    
reflection that nothing is1 but all     
things become2 no name can detain or fix
 them4 ,are not these speculations      
charming1 ,theaetetus1 and very good for
 a person in your interesting situation8
 ,i am offering you specimens of other  
men's wisdom1 because ,i have no wisdom 
of my own1 and ,i want to deliver you of
 something2 and presently we will see   
whether you have brought forth wind or  
not4 ,tell me1 then1 what do you think  
of the notion that ,all things are      
becoming8'  ',when ,i hear your         
arguments1 ,i am marvellously ready to  
assent4'  ',but ,i ought not to conceal 
from you that there is a serious        
objection which may be urged against    
this doctrine of ,protagoras4 ,for there
 are states1 such as madness and        
dreaming1 in which perception is false2 

and half our life is spent in dreaming2 
and who can say that at this instant we 
are not dreaming8 ,even the fancies of  
madmen are real at the time4 ,but if    
knowledge is perception1 how can we     
distinguish between the true and the    
false in such cases8 ,having stated the 
objection1 ,i will now state the answer4
 ,protagoras would deny the continuity  
of phenomena2 he would say that what is 
different is entirely different1 and    
whether active or passive has a         
different power4 ,there are infinite    
agents and patients in the world1 and   
these produce in every combination of   
them a different perception4 ,take      
myself as an instance3--,socrates may be
 ill or he may be well1--and remember   
that ,socrates1 with all his accidents1 
is spoken of4 ,the wine which ,i drink  
when ,i am well is pleasant to me1 but  
the same wine is unpleasant to me when  
,i am ill4 ,and there is nothing else   
from which ,i can receive the same      
impression1 nor can another receive the 

same impression from the wine4 ,neither 
can ,i and the object of sense become   
separately what we become together4 ,for
 the one in becoming is relative to the 
other1 but they have no other relation2 
and the combination of them is absolute 
at each moment4 7,in modern language1   
the act of sensation is really          
indivisible1 though capable of a mental 
analysis into subject and object47 ,my  
sensation alone is true1 and true to me 
only4 ,and therefore1 as ,protagoras    
says1 ,to myself ,i am the judge of what
 is and what is not4 ,thus the flux of  
,homer and ,heracleitus1 the great      
,protagorean saying that ,man is the    
measure of all things1 the doctrine of  
,theaetetus that ,knowledge is          
perception1 have all the same meaning4  
,and this is thy new-born child1 which  
by my art ,i have brought to light2 and 
you must not be angry if instead of     
rearing your infant we expose him4'     
',theaetetus will not be angry1' says   
,theodorus2 'he is very good-natured4   

,but ,i should like to know1 ,socrates1 
whether you mean to say that all this is
 untrue8'  ',first reminding you that ,i
 am not the bag which contains the      
arguments1 but that ,i extract them from
 ,theaetetus1 shall ,i tell you what    
amazes me in your friend ,protagoras8'  
',what may that be8'  ',i like his      
doctrine that what appears is2 but ,i   
wonder that he did not begin his great  
work on ,truth with a declaration that a
 pig1 or a dog-faced baboon1 or any     
other monster which has sensation1 is a 
measure of all things2 then1 while we   
were reverencing him as a god1 he might 
have produced a magnificent effect by   
expounding to us that he was no wiser   
than a tadpole4 ,for if sensations are  
always true1 and one man's discernment  
is as good as another's1 and every man  
is his own judge1 and everything that he
 judges is right and true1 then what    
need of ,protagoras to be our instructor
 at a high figure2 and why should we be 
less knowing than he is1 or have to go  

to him1 if every man is the measure of  
all things8 ,my own art of midwifery1   
and all dialectic1 is an enormous folly1
 if ,protagoras' ,truth be indeed truth1
 and the philosopher is not merely      
amusing himself by giving oracles out of
 his book4'  ,theodorus thinks that     
,socrates is unjust to his master1      
,protagoras2 but he is too old and stiff
 to try a fall with him1 and therefore  
refers him to ,theaetetus1 who is       
already driven out of his former opinion
 by the arguments of ,socrates4         
,socrates then takes up the defence of  
,protagoras1 who is supposed to reply in
 his own person--',good people1 you sit 
and declaim about the gods1 of whose    
existence or non-existence ,i have      
nothing to say1 or you discourse about  
man being reduced to the level of the   
brutes2 but what proof have you of your 
statements8 ,and yet surely you and     
,theodorus had better reflect whether   
probability is a safe guide4 ,theodorus 
would be a bad geometrician if he had   

nothing better to offer4'444,theaetetus 
is affected by the appeal to geometry1  
and ,socrates is induced by him to put  
the question in a new form4 ,he proceeds
 as follows3--',should we say that we   
know what we see and hear1--e4g4 the    
sound of words or the sight of letters  
in a foreign tongue8'  ',we should say  
that the figures of the letters1 and the
 pitch of the voice in uttering them1   
were known to us1 but not the meaning of
 them4'  ',excellent2 ,i want you to    
grow1 and therefore ,i will leave that  
answer and ask another question3 ,is not
 seeing perceiving8' ',very true4' ',and
 he who sees knows8' ',yes4' ',and he   
who remembers1 remembers that which he  
sees and knows8' ',very true4' ',but if 
he closes his eyes1 does he not         
remember8' ',he does4' ',then he may    
remember and not see2 and if seeing is  
knowing1 he may remember and not know4  
,is not this a reductio ad absurdum of  
the hypothesis that knowledge is        
sensible perception8 ,yet perhaps we are

 crowing too soon2 and if ,protagoras1  
the father of the myth1 had been alive1 
the result might have been very         
different4 ,but he is dead1 and         
,theodorus1 whom he left guardian of his
 orphan1 has not been very zealous in   
defending him4'  ,theodorus objects that
 ,callias is the true guardian1 but he  
hopes that ,socrates will come to the   
rescue4 ,socrates prefaces his defence  
by resuming the attack4 ,he asks whether
 a man can know and not know at the same
 time8 ',impossible4' ,quite possible1  
if you maintain that seeing is knowing4 
,the confident adversary1 suiting the   
action to the word1 shuts one of your   
eyes2 and now1 says he1 you see and do  
not see1 but do you know and not know8  
,and a fresh opponent darts from his    
ambush1 and transfers to knowledge the  
terms which are commonly applied to     
sight4 ,he asks whether you can know    
near and not at a distance2 whether you 
can have a sharp and also a dull        
knowledge4 ,while you are wondering at  

his incomparable wisdom1 he gets you    
into his power1 and you will not escape 
until you have come to an understanding 
with him about the money which is to be 
paid for your release4  ,but ,protagoras
 has not yet made his defence2 and      
already he may be heard contemptuously  
replying that he is not responsible for 
the admissions which were made by a boy1
 who could not foresee the coming move1 
and therefore had answered in a manner  
which enabled ,socrates to raise a laugh
 against himself4 ',but ,i cannot be    
fairly charged1' he will say1 'with an  
answer which ,i should not have given2  
for ,i never maintained that the memory 
of a feeling is the same as a feeling1  
or denied that a man might know and not 
know the same thing at the same time4   
,or1 if you will have extreme precision1
 ,i say that man in different relations 
is many or rather infinite in number4   
,and ,i challenge you1 either to show   
that his perceptions are not individual1
 or that if they are1 what appears to   

him is not what is4 ,as to your pigs and
 baboons1 you are yourself a pig1 and   
you make my writings a sport of other   
swine4 ,but ,i still affirm that man is 
the measure of all things1 although ,i  
admit that one man may be a thousand    
times better than another1 in proportion
 as he has better impressions4 ,neither 
do ,i deny the existence of wisdom or of
 the wise man4 ,but ,i maintain that    
wisdom is a practical remedial power of 
turning evil into good1 the bitterness  
of disease into the sweetness of health1
 and does not consist in any greater    
truth or superior knowledge4 ,for the   
impressions of the sick are as true as  
the impressions of the healthy2 and the 
sick are as wise as the healthy4 ,nor   
can any man be cured of a false opinion1
 for there is no such thing2 but he may 
be cured of the evil habit which        
generates in him an evil opinion4 ,this 
is effected in the body by the drugs of 
the physician1 and in the soul by the   
words of the ,sophist2 and the new state

 or opinion is not truer1 but only      
better than the old4 ,and philosophers  
are not tadpoles1 but physicians and    
husbandmen1 who till the soil and infuse
 health into animals and plants1 and    
make the good take the place of the     
evil1 both in individuals and states4   
,wise and good rhetoricians make the    
good to appear just in states 7for that 
is just which appears just to a state71 
and in return1 they deserve to be well  
paid4 ,and you1 ,socrates1 whether you  
please or not1 must continue to be a    
measure4 ,this is my defence1 and ,i    
must request you to meet me fairly4 ,we 
are professing to reason1 and not merely
 to dispute2 and there is a great       
difference between reasoning and        
disputation4 ,for the disputer is always
 seeking to trip up his opponent2 and   
this is a mode of argument which        
disgusts men with philosophy as they    
grow older4 ,but the reasoner is trying 
to understand him and to point out his  
errors to him1 whether arising from his 

own or from his companion's fault2 he   
does not argue from the customary use of
 names1 which the vulgar pervert in all 
manner of ways4 ,if you are gentle to an
 adversary he will follow and love you2 
and if defeated he will lay the blame on
 himself1 and seek to escape from his   
own prejudices into philosophy4 ,i would
 recommend you1 ,socrates1 to adopt this
 humaner method1 and to avoid captious  
and verbal criticisms4'  ,such1         
,theodorus1 is the very slight help     
which ,i am able to afford to your      
friend2 had he been alive1 he would have
 helped himself in far better style4    
',you have made a most valorous         
defence4'  ,yes2 but did you observe    
that ,protagoras bade me be serious1 and
 complained of our getting up a laugh   
against him with the aid of a boy8 ,he  
meant to intimate that you must take the
 place of ,theaetetus1 who may be wiser 
than many bearded men1 but not wiser    
than you1 ,theodorus4  ',the rule of the
 ,spartan ,palaestra is1 ,strip or      

depart2 but you are like the giant      
,antaeus1 and will not let me depart    
unless ,i try a fall with you4'  ,yes1  
that is the nature of my complaint4 ,and
 many a ,hercules1 many a ,theseus      
mighty in deeds and words has broken my 
head2 but ,i am always at this rough    
game4 ,please1 then1 to favour me4  ',on
 the condition of not exceeding a single
 fall1 ,i consent4'  ,socrates now      
resumes the argument4 ,as he is very    
desirous of doing justice to            
,protagoras1 he insists on citing his   
own words1--',what appears to each man  
is to him4' ,and how1 asks ,socrates1   
are these words reconcileable with the  
fact that all mankind are agreed in     
thinking themselves wiser than others in
 some respects1 and inferior to them in 
others8 ,in the hour of danger they are 
ready to fall down and worship any one  
who is their superior in wisdom as if he
 were a god4 ,and the world is full of  
men who are asking to be taught and     
willing to be ruled1 and of other men   

who are willing to rule and teach them4 
,all which implies that men do judge of 
one another's impressions1 and think    
some wise and others foolish4 ,how will 
,protagoras answer this argument8 ,for  
he cannot say that no one deems another 
ignorant or mistaken4 ,if you form a    
judgment1 thousands and tens of         
thousands are ready to maintain the     
opposite4 ,the multitude may not and do 
not agree in ,protagoras' own thesis    
that ',man is the measure of all        
things2' and then who is to decide8     
,upon his own showing must not his      
'truth' depend on the number of         
suffrages1 and be more or less true in  
proportion as he has more or fewer of   
them8 ,and he must acknowledge further1 
that they speak truly who deny him to   
speak truly1 which is a famous jest4    
,and if he admits that they speak truly 
who deny him to speak truly1 he must    
admit that he himself does not speak    
truly4 ,but his opponents will refuse to
 admit this of themselves1 and he must  

allow that they are right in their      
refusal4 ,the conclusion is1 that all   
mankind1 including ,protagoras himself1 
will deny that he speaks truly2 and his 
truth will be true neither to himself   
nor to anybody else4  ,theodorus is     
inclined to think that this is going too
 far4 ,socrates ironically replies1 that
 he is not going beyond the truth4 ,but 
if the old ,protagoras could only pop   
his head out of the world below1 he     
would doubtless give them both a sound  
castigation and be off to the shades in 
an instant4 ,seeing that he is not      
within call1 we must examine the        
question for ourselves4 ,it is clear    
that there are great differences in the 
understandings of men4 ,admitting1 with 
,protagoras1 that immediate sensations  
of hot1 cold1 and the like1 are to each 
one such as they appear1 yet this       
hypothesis cannot be extended to        
judgments or opinions4 ,and even if we  
were to admit further1--and this is the 
view of some who are not thorough-going 

followers of ,protagoras1--that right   
and wrong1 holy and unholy1 are to each 
state or individual such as they appear1
 still ,protagoras will not venture to  
maintain that every man is equally the  
measure of expediency1 or that the thing
 which seems is expedient to every one4 
,but this begins a new question4 ',well1
 ,socrates1 we have plenty of leisure4  
,yes1 we have1 and1 after the manner of 
philosophers1 we are digressing2 ,i have
 often observed how ridiculous this     
habit of theirs makes them when they    
appear in court4 ',what do you mean8' ,i
 mean to say that a philosopher is a    
gentleman1 but a lawyer is a servant4   
,the one can have his talk out1 and     
wander at will from one subject to      
another1 as the fancy takes him2 like   
ourselves1 he may be long or short1 as  
he pleases4 ,but the lawyer is always in
 a hurry2 there is the clepsydra        
limiting his time1 and the brief        
limiting his topics1 and his adversary  
is standing over him and exacting his   

rights4 ,he is a servant disputing about
 a fellow-servant before his master1 who
 holds the cause in his hands2 the path 
never diverges1 and often the race is   
for his life4 ,such experiences render  
him keen and shrewd2 he learns the arts 
of flattery1 and is perfect in the      
practice of crooked ways2 dangers have  
come upon him too soon1 when the        
tenderness of youth was unable to meet  
them with truth and honesty1 and he has 
resorted to counter-acts of dishonesty  
and falsehood1 and become warped and    
distorted2 without any health or freedom
 or sincerity in him he has grown up to 
manhood1 and is or esteems himself to be
 a master of cunning4 ,such are the     
lawyers2 will you have the companion    
picture of philosophers8 or will this be
 too much of a digression8  ',nay1      
,socrates1 the argument is our servant1 
and not our master4 ,who is the judge or
 where is the spectator1 having a right 
to control us8'  ,i will describe the   
leaders1 then3 for the inferior sort are

 not worth the trouble4 ,the lords of   
philosophy have not learned the way to  
the dicastery or ecclesia2 they neither 
see nor hear the laws and votes of the  
state1 written or recited2 societies1   
whether political or festive1 clubs1 and
 singing maidens do not enter even into 
their dreams4 ,and the scandals of      
persons or their ancestors1 male and    
female1 they know no more than they can 
tell the number of pints in the ocean4  
,neither are they conscious of their own
 ignorance2 for they do not practise    
singularity in order to gain reputation1
 but the truth is1 that the outer form  
of them only is residing in the city2   
the inner man1 as ,pindar says1 is going
 on a voyage of discovery1 measuring as 
with line and rule the things which are 
under and in the earth1 interrogating   
the whole of nature1 only not           
condescending to notice what is near    
them4  ',what do you mean1 ,socrates8'  
,i will illustrate my meaning by the    
jest of the witty maid-servant1 who saw 

,thales tumbling into a well1 and said  
of him1 that he was so eager to know    
what was going on in heaven1 that he    
could not see what was before his feet4 
,this is applicable to all philosophers4
 ,the philosopher is unacquainted with  
the world2 he hardly knows whether his  
neighbour is a man or an animal4 ,for he
 is always searching into the essence of
 man1 and enquiring what such a nature  
ought to do or suffer different from any
 other4 ,hence1 on every occasion in    
private life and public1 as ,i was      
saying1 when he appears in a law-court  
or anywhere1 he is the joke1 not only of
 maid-servants1 but of the general herd1
 falling into wells and every sort of   
disaster2 he looks such an awkward1     
inexperienced creature1 unable to say   
anything personal1 when he is abused1 in
 answer to his adversaries 7for he knows
 no evil of any one72 and when he hears 
the praises of others1 he cannot help   
laughing from the bottom of his soul at 
their pretensions2 and this also gives  

him a ridiculous appearance4 ,a king or 
tyrant appears to him to be a kind of   
swine-herd or cow-herd1 milking away at 
an animal who is much more troublesome  
and dangerous than cows or sheep2 like  
the cow-herd1 he has no time to be      
educated1 and the pen in which he keeps 
his flock in the mountains is surrounded
 by a wall4 ,when he hears of large     
landed properties of ten thousand acres 
or more1 he thinks of the whole earth2  
or if he is told of the antiquity of a  
family1 he remembers that every one has 
had myriads of progenitors1 rich and    
poor1 ,greeks and barbarians1 kings and 
slaves4 ,and he who boasts of his       
descent from ,amphitryon in the         
twenty-fifth generation1 may1 if he     
pleases1 add as many more1 and double   
that again1 and our philosopher only    
laughs at his inability to do a larger  
sum4 ,such is the man at whom the vulgar
 scoff2 he seems to them as if he could 
not mind his feet4 ',that is very true1 
,socrates4' ,but when he tries to draw  

the quick-witted lawyer out of his pleas
 and rejoinders to the contemplation of 
absolute justice or injustice in their  
own nature1 or from the popular praises 
of wealthy kings to the view of         
happiness and misery in themselves1 or  
to the reasons why a man should seek    
after the one and avoid the other1 then 
the situation is reversed2 the little   
wretch turns giddy1 and is ready to fall
 over the precipice2 his utterance      
becomes thick1 and he makes himself     
ridiculous1 not to servant-maids1 but to
 every man of liberal education4 ,such  
are the two pictures3 the one of the    
philosopher and gentleman1 who may be   
excused for not having learned how to   
make a bed1 or cook up flatteries2 the  
other1 a serviceable knave1 who hardly  
knows how to wear his cloak1--still less
 can he awaken harmonious thoughts or   
hymn virtue's praises4  ',if the world1 
,socrates1 were as ready to receive your
 words as ,i am1 there would be greater 
peace and less evil among mankind4'     

,evil1 ,theodorus1 must ever remain in  
this world to be the antagonist of good1
 out of the way of the gods in heaven4  
,wherefore also we should fly away from 
ourselves to them2 and to fly to them is
 to become like them2 and to become like
 them is to become holy1 just and true4 
,but many live in the old wives' fable  
of appearances2 they think that you     
should follow virtue in order that you  
may seem to be good4 ,and yet the truth 
is1 that ,god is righteous2 and of men1 
he is most like him who is most         
righteous4 ,to know this is wisdom2 and 
in comparison of this the wisdom of the 
arts or the seeming wisdom of           
politicians is mean and common4 ,the    
unrighteous man is apt to pride himself 
on his cunning2 when others call him    
rogue1 he says to himself3 ',they only  
mean that ,i am one who deserves to     
live1 and not a mere burden of the      
earth4' ,but he should reflect that his 
ignorance makes his condition worse than
 if he knew4 ,for the penalty of        

injustice is not death or stripes1 but  
the fatal necessity of becoming more and
 more unjust4 ,two patterns of life are 
set before him2 the one blessed and     
divine1 the other godless and wretched2 
and he is growing more and more like the
 one and unlike the other4 ,he does not 
see that if he continues in his cunning1
 the place of innocence will not receive
 him after death4 ,and yet if such a man
 has the courage to hear the argument   
out1 he often becomes dissatisfied with 
himself1 and has no more strength in him
 than a child4--,but we have digressed  
enough4  ',for my part1 ,socrates1 ,i   
like the digressions better than the    
argument1 because ,i understand them    
better4'  ,to return4 ,when we left off1
 the ,protagoreans and ,heracliteans    
were maintaining that the ordinances of 
the ,state were just1 while they lasted4
 ,but no one would maintain that the    
laws of the ,state were always good or  
expedient1 although this may be the     
intention of them4 ,for the expedient   

has to do with the future1 about which  
we are liable to mistake4 ,now1 would   
,protagoras maintain that man is the    
measure not only of the present and     
past1 but of the future2 and that there 
is no difference in the judgments of men
 about the future8 ,would an untrained  
man1 for example1 be as likely to know  
when he is going to have a fever1 as the
 physician who attended him8 ,and if    
they differ in opinion1 which of them is
 likely to be right2 or are they both   
right8 ,is not a vine-grower a better   
judge of a vintage which is not yet     
gathered1 or a cook of a dinner which is
 in preparation1 or ,protagoras of the  
probable effect of a speech than an     
ordinary person8 ,the last example      
speaks 'ad hominen4' ,for ,protagoras   
would never have amassed a fortune if   
every man could judge of the future for 
himself4 ,he is1 therefore1 compelled to
 admit that he is a measure2 but ,i1 who
 know nothing1 am not equally convinced 
that ,i am4 ,this is one way of refuting

 him2 and he is refuted also by the     
authority which he attributes to the    
opinions of others1 who deny his        
opinions4 ,i am not equally sure that we
 can disprove the truth of immediate    
states of feeling4 ,but this leads us to
 the doctrine of the universal flux1    
about which a battle-royal is always    
going on in the cities of ,ionia4 ',yes2
 the ,ephesians are downright mad about 
the flux2 they cannot stop to argue with
 you1 but are in perpetual motion1      
obedient to their text-books4 ,their    
restlessness is beyond expression1 and  
if you ask any of them a question1 they 
will not answer1 but dart at you some   
unintelligible saying1 and another and  
another1 making no way either with      
themselves or with others2 for nothing  
is fixed in them or their ideas1--they  
are at war with fixed principles4' ,i   
suppose1 ,theodorus1 that you have never
 seen them in time of peace1 when they  
discourse at leisure to their disciples8
 ',disciples6 they have none2 they are a

 set of uneducated fanatics1 and each of
 them says of the other that they have  
no knowledge4 ,we must trust to         
ourselves1 and not to them for the      
solution of the problem4' ,well1 the    
doctrine is old1 being derived from the 
poets1 who speak in a figure of ,oceanus
 and ,tethys2 the truth was once        
concealed1 but is now revealed by the   
superior wisdom of a later generation1  
and made intelligible to the cobbler1   
who1 on hearing that all is in motion1  
and not some things only1 as he         
ignorantly fancied1 may be expected to  
fall down and worship his teachers4 ,and
 the opposite doctrine must not be      
forgotten3--       ',alone being remains
 unmoved which is the name for all1'  as
 ,parmenides affirms4 ,thus we are in   
the midst of the fray2 both parties are 
dragging us to their side2 and we are   
not certain which of them are in the    
right2 and if neither1 then we shall be 
in a ridiculous position1 having to set 
up our own opinion against ancient and  

famous men4  ,let us first approach the 
river-gods1 or patrons of the flux4     
,when they speak of motion1 must they   
not include two kinds of motion1 change 
of place and change of nature8--,and all
 things must be supposed to have both   
kinds of motion2 for if not1 the same   
things would be at rest and in motion1  
which is contrary to their theory4 ,and 
did we not say1 that all sensations     
arise thus3 they move about between the 
agent and patient together with a       
perception1 and the patient ceases to be
 a perceiving power and becomes a       
percipient1 and the agent a quale       
instead of a quality2 but neither has   
any absolute existence8 ,but now we make
 the further discovery1 that neither    
white or whiteness1 nor any sense or    
sensation1 can be predicated of         
anything1 for they are in a perpetual   
flux4 ,and therefore we must modify the 
doctrine of ,theaetetus and ,protagoras1
 by asserting further that knowledge is 
and is not sensation2 and of everything 

we must say equally1 that this is and is
 not1 or becomes or becomes not4 ,and   
still the word 'this' is not quite      
correct1 for language fails in the      
attempt to express their meaning4  ,at  
the close of the discussion1 ,theodorus 
claims to be released from the argument1
 according to his agreement4 ,but       
,theaetetus insists that they shall     
proceed to consider the doctrine of     
rest4 ,this is declined by ,socrates1   
who has too much reverence for the great
 ,parmenides lightly to attack him4 7,we
 shall find that he returns to the      
doctrine of rest in the ,sophist2 but at
 present he does not wish to be diverted
 from his main purpose1 which is1 to    
deliver ,theaetetus of his conception of
 knowledge47 ,he proceeds to interrogate
 him further4 ,when he says that        
'knowledge is in perception1' with what 
does he perceive8 ,the first answer is1 
that he perceives sights with the eye1  
and sounds with the ear4 ,this leads    
,socrates to make the reflection that   

nice distinctions of words are sometimes
 pedantic1 but sometimes necessary2 and 
he proposes in this case to substitute  
the word 'through' for 'with4' ,for the 
senses are not like the ,trojan warriors
 in the horse1 but have a common centre 
of perception1 in which they all meet4  
,this common principle is able to       
compare them with one another1 and must 
therefore be distinct from them 7compare
 ,republic74 ,and as there are facts of 
sense which are perceived through the   
organs of the body1 there are also      
mathematical and other abstractions1    
such as sameness and difference1        
likeness and unlikeness1 which the soul 
perceives by herself4 ,being is the most
 universal of these abstractions4 ,the  
good and the beautiful are abstractions 
of another kind1 which exist in relation
 and which above all others the mind    
perceives in herself1 comparing within  
her past1 present1 and future4 ,for     
example2 we know a thing to be hard or  
soft by the touch1 of which the         

perception is given at birth to men and 
animals4 ,but the essence of hardness or
 softness1 or the fact that this        
hardness is1 and is the opposite of     
softness1 is slowly learned by          
reflection and experience4 ,mere        
perception does not reach being1 and    
therefore fails of truth2 and therefore 
has no share in knowledge4 ,but if so1  
knowledge is not perception4 ,what then 
is knowledge8 ,the mind1 when occupied  
by herself with being1 is said to have  
opinion--shall we say that ',knowledge  
is true opinion'8 ,but still an old     
difficulty recurs2 we ask ourselves1    
',how is false opinion possible8' ,this 
difficulty may be stated as follows3--  
,either we know or do not know a thing  
7for the intermediate processes of      
learning and forgetting need not at     
present be considered72 and in thinking 
or having an opinion1 we must either    
know or not know that which we think1   
and we cannot know and be ignorant at   
the same time2 we cannot confuse one    

thing which we do not know1 with another
 thing which we do not know2 nor can we 
think that which we do not know to be   
that which we know1 or that which we    
know to be that which we do not know4   
,and what other case is conceivable1    
upon the supposition that we either know
 or do not know all things8 ,let us try 
another answer in the sphere of being3  
',when a man thinks1 and thinks that    
which is not4' ,but would this hold in  
any parallel case8 ,can a man see and   
see nothing8 or hear and hear nothing8  
or touch and touch nothing8 ,must he not
 see1 hear1 or touch some one existing  
thing8 ,for if he thinks about nothing  
he does not think1 and not thinking he  
cannot think falsely4 ,and so the path  
of being is closed against us1 as well  
as the path of knowledge4 ,but may there
 not be 'heterodoxy1' or transference of
 opinion2--,i mean1 may not one thing be
 supposed to be another8 ,theaetetus is 
confident that this must be 'the true   
falsehood1' when a man puts good for    

evil or evil for good4 ,socrates will   
not discourage him by attacking the     
paradoxical expression 'true falsehood1'
 but passes on4 ,the new notion involves
 a process of thinking about two things1
 either together or alternately4 ,and   
thinking is the conversing of the mind  
with herself1 which is carried on in    
question and answer1 until she no longer
 doubts1 but determines and forms an    
opinion4 ,and false opinion consists in 
saying to yourself1 that one thing is   
another4 ,but did you ever say to       
yourself1 that good is evil1 or evil    
good8 ,even in sleep1 did you ever      
imagine that odd was even8 ,or did any  
man in his senses ever fancy that an ox 
was a horse1 or that two are one8 ,so   
that we can never think one thing to be 
another2 for you must not meet me with  
the verbal quibble that one--eteron--is 
other--eteron 7both 'one' and 'other' in
 ,greek are called 'other'--eteron74 ,he
 who has both the two things in his     
mind1 cannot misplace them2 and he who  

has only one of them in his mind1 cannot
 misplace them--on either supposition   
transplacement is inconceivable4  ,but  
perhaps there may still be a sense in   
which we can think that which we do not 
know to be that which we know3 e4g4     
,theaetetus may know ,socrates1 but at a
 distance he may mistake another person 
for him4 ,this process may be conceived 
by the help of an image4 ,let us suppose
 that every man has in his mind a block 
of wax of various qualities1 the gift of
 ,memory1 the mother of the ,muses2 and 
on this he receives the seal or stamp of
 those sensations and perceptions which 
he wishes to remember4 ,that which he   
succeeds in stamping is remembered and  
known by him as long as the impression  
lasts2 but that1 of which the impression
 is rubbed out or imperfectly made1 is  
forgotten1 and not known4 ,no one can   
think one thing to be another1 when he  
has the memorial or seal of both of     
these in his soul1 and a sensible       
impression of neither2 or when he knows 

one and does not know the other1 and has
 no memorial or seal of the other2 or   
when he knows neither2 or when he       
perceives both1 or one and not the      
other1 or neither2 or when he perceives 
and knows both1 and identifies what he  
perceives with what he knows 7this is   
still more impossible72 or when he does 
not know one1 and does not know and does
 not perceive the other2 or does not    
perceive one1 and does not know and does
 not perceive the other2 or has no      
perception or knowledge of either--all  
these cases must be excluded4 ,but he   
may err when he confuses what he knows  
or perceives1 or what he perceives and  
does not know1 with what he knows1 or   
what he knows and perceives with what he
 knows and perceives4  ,theaetetus is   
unable to follow these distinctions2    
which ,socrates proceeds to illustrate  
by examples1 first of all remarking1    
that knowledge may exist without        
perception1 and perception without      
knowledge4 ,i may know ,theodorus and   

,theaetetus and not see them2 ,i may see
 them1 and not know them4 ',that ,i     
understand4' ,but ,i could not mistake  
one for the other if ,i knew you both1  
and had no perception of either2 or if  
,i knew one only1 and perceived neither2
 or if ,i knew and perceived neither1 or
 in any other of the excluded cases4    
,the only possibility of error is3 #ast1
 when knowing you and ,theodorus1 and   
having the impression of both of you on 
the waxen block1 ,i1 seeing you both    
imperfectly and at a distance1 put the  
foot in the wrong shoe--that is to say1 
put the seal or stamp on the wrong      
object3 or #bndly1 when knowing both of 
you ,i only see one2 or when1 seeing and
 knowing you both1 ,i fail to identify  
the impression and the object4 ,but     
there could be no error when perception 
and knowledge correspond4  ,the waxen   
block in the heart of a man's soul1 as  
,i may say in the words of ,homer1 who  
played upon the words ker and keros1 may
 be smooth and deep1 and large enough1  

and then the signs are clearly marked   
and lasting1 and do not get confused4   
,but in the 'hairy heart1' as the       
all-wise poet sings1 when the wax is    
muddy or hard or moist1 there is a      
corresponding confusion and want of     
retentiveness2 in the muddy and impure  
there is indistinctness1 and still more 
in the hard1 for there the impressions  
have no depth of wax1 and in the moist  
they are too soon effaced4 ,yet greater 
is the indistinctness when they are all 
jolted together in a little soul1 which 
is narrow and has no room4 ,these are   
the sort of natures which have false    
opinion2 from stupidity they see and    
hear and think amiss2 and this is       
falsehood and ignorance4 ,error1 then1  
is a confusion of thought and sense4    
,theaetetus is delighted with this      
explanation4 ,but ,socrates has no      
sooner found the new solution than he   
sinks into a fit of despondency4 ,for an
 objection occurs to him3--,may there   
not be errors where there is no         

confusion of mind and sense8 e4g4 in    
numbers4 ,no one can confuse the man    
whom he has in his thoughts with the    
horse which he has in his thoughts1 but 
he may err in the addition of five and  
seven4 ,and observe that these are      
purely mental conceptions4 ,thus we are 
involved once more in the dilemma of    
saying1 either that there is no such    
thing as false opinion1 or that a man   
knows what he does not know4  ,we are at
 our wit's end1 and may therefore be    
excused for making a bold diversion4    
,all this time we have been repeating   
the words 'know1' 'understand1' yet we  
do not know what knowledge is4 ',why1   
,socrates1 how can you argue at all     
without using them8' ,nay1 but the true 
hero of dialectic would have forbidden  
me to use them until ,i had explained   
them4 ,and ,i must explain them now4    
,the verb 'to know' has two senses1 to  
have and to possess knowledge1 and ,i   
distinguish 'having' from 'possessing4' 
,a man may possess a garment which he   

does not wear2 or he may have wild birds
 in an aviary2 these in one sense he    
possesses1 and in another he has none of
 them4 ,let this aviary be an image of  
the mind1 as the waxen block was2 when  
we are young1 the aviary is empty2 after
 a time the birds are put in2 for under 
this figure we may describe different   
forms of knowledge2--there are some of  
them in groups1 and some single1 which  
are flying about everywhere2 and let us 
suppose a hunt after the science of odd 
and even1 or some other science4 ,the   
possession of the birds is clearly not  
the same as the having them in the hand4
 ,and the original chase of them is not 
the same as taking them in the hand when
 they are already caged4  ,this         
distinction between use and possession  
saves us from the absurdity of supposing
 that we do not know what we know1      
because we may know in one sense1 i4e4  
possess1 what we do not know in another1
 i4e4 use4 ,but have we not escaped one 
difficulty only to encounter a greater8 

,for how can the exchange of two kinds  
of knowledge ever become false opinion8 
,as well might we suppose that ignorance
 could make a man know1 or that         
blindness could make him see4           
,theaetetus suggests that in the aviary 
there may be flying about mock birds1 or
 forms of ignorance1 and we put forth   
our hands and grasp ignorance1 when we  
are intending to grasp knowledge4 ,but  
how can he who knows the forms of       
knowledge and the forms of ignorance    
imagine one to be the other8 ,is there  
some other form of knowledge which      
distinguishes them8 and another1 and    
another8 ,thus we go round and round in 
a circle and make no progress4  ,all    
this confusion arises out of our attempt
 to explain false opinion without having
 explained knowledge4 ,what then is     
knowledge8 ,theaetetus repeats that     
knowledge is true opinion4 ,but this    
seems to be refuted by the instance of  
orators and judges4 ,for surely the     
orator cannot convey a true knowledge of

 crimes at which the judges were not    
present2 he can only persuade them1 and 
the judge may form a true opinion and   
truly judge4 ,but if true opinion were  
knowledge they could not have judged    
without knowledge4  ,once more4         
,theaetetus offers a definition which he
 has heard3 ,knowledge is true opinion  
accompanied by definition or            
explanation4 ,socrates has had a similar
 dream1 and has further heard that the  
first elements are names only1 and that 
definition or explanation begins when   
they are combined2 the letters are      
unknown1 the syllables or combinations  
are known4 ,but this new hypothesis when
 tested by the letters of the alphabet  
is found to break down4 ,the first      
syllable of ,socrates' name is ,,so4    
,but what is ,,so8 ,two letters1 ,s and 
,o1 a sibilant and a vowel1 of which no 
further explanation can be given4 ,and  
how can any one be ignorant of either of
 them1 and yet know both of them8 ,there
 is1 however1 another alternative3--,we 

may suppose that the syllable has a     
separate form or idea distinct from the 
letters or parts4 ,the all of the parts 
may not be the whole4 ,theaetetus is    
very much inclined to adopt this        
suggestion1 but when interrogated by    
,socrates he is unable to draw any      
distinction between the whole and all   
the parts4 ,and if the syllables have no
 parts1 then they are those original    
elements of which there is no           
explanation4 ,but how can the syllable  
be known if the letter remains unknown8 
,in learning to read as children1 we are
 first taught the letters and then the  
syllables4 ,and in music1 the notes1    
which are the letters1 have a much more 
distinct meaning to us than the         
combination of them4  ,once more1 then1 
we must ask the meaning of the          
statement1 that ',knowledge is right    
opinion1 accompanied by explanation or  
definition4' ,explanation may mean1 7#a7
 the reflection or expression of a man's
 thoughts--but every man who is not deaf

 and dumb is able to express his        
thoughts--or 7#b7 the enumeration of the
 elements of which anything is composed4
 ,a man may have a true opinion about a 
waggon1 but then1 and then only1 has he 
knowledge of a waggon when he is able to
 enumerate the hundred planks of        
,hesiod4 ,or he may know the syllables  
of the name ,theaetetus1 but not the    
letters2 yet not until he knows both can
 he be said to have knowledge as well as
 opinion4 ,but on the other hand he may 
know the syllable ',the' in the name    
,theaetetus1 yet he may be mistaken     
about the same syllable in the name     
,theodorus1 and in learning to read we  
often make such mistakes4 ,and even if  
he could write out all the letters and  
syllables of your name in order1 still  
he would only have right opinion4 ,yet  
there may be a third meaning of the     
definition1 besides the image or        
expression of the mind1 and the         
enumeration of the elements1 viz4 7#c7  
perception of difference4  ,for example1

 ,i may see a man who has eyes1 nose1   
and mouth2--that will not distinguish   
him from any other man4 ,or he may have 
a snub-nose and prominent eyes2--that   
will not distinguish him from myself and
 you and others who are like me4 ,but   
when ,i see a certain kind of           
snub-nosedness1 then ,i recognize       
,theaetetus4 ,and having this sign of   
difference1 ,i have knowledge4 ,but have
 ,i knowledge or opinion of this        
difference2 if ,i have only opinion ,i  
have not knowledge2 if ,i have knowledge
 we assume a disputed term2 for         
knowledge will have to be defined as    
right opinion with knowledge of         
difference4  ,and so1 ,theaetetus1      
knowledge is neither perception nor true
 opinion1 nor yet definition            
accompanying true opinion4 ,and ,i have 
shown that the children of your brain   
are not worth rearing4 ,are you still in
 labour1 or have you brought all you    
have to say about knowledge to the      
birth8 ,if you have any more thoughts1  

you will be the better for having got   
rid of these2 or if you have none1 you  
will be the better for not fancying that
 you know what you do not know4 ,observe
 the limits of my art1 which1 like my   
mother's1 is an art of midwifery2 ,i do 
not pretend to compare with the good and
 wise of this and other ages4  ,and now 
,i go to meet ,meletus at the porch of  
the ,king ,archon2 but to-morrow ,i     
shall hope to see you again1 ,theodorus1
 at this place4  444  ,i4 ,the saying of
 ,theaetetus1 that ',knowledge is       
sensible perception1' may be assumed to 
be a current philosophical opinion of   
the age4 ',the ancients1' as ,aristotle 
7,de ,anim47 says1 citing a verse of    
,empedocles1 'affirmed knowledge to be  
the same as perception4' ,we may now    
examine these words1 first1 with        
reference to their place in the history 
of philosophy1 and secondly1 in relation
 to modern speculations4  7a7 ,in the   
age of ,socrates the mind was passing   
from the object to the subject4 ,the    

same impulse which a century before had 
led men to form conceptions of the      
world1 now led them to frame general    
notions of the human faculties and      
feelings1 such as memory1 opinion1 and  
the like4 ,the simplest of these is     
sensation1 or sensible perception1 by   
which ,plato seems to mean the          
generalized notion of feelings and      
impressions of sense1 without           
determining whether they are conscious  
or not4  ,the theory that ',knowledge is
 sensible perception' is the antithesis 
of that which derives knowledge from the
 mind 7,theaet471 or which assumes the  
existence of ideas independent of the   
mind 7,parm474 ,yet from their extreme  
abstraction these theories do not       
represent the opposite poles of thought 
in the same way that the corresponding  
differences would in modern philosophy4 
,the most ideal and the most sensational
 have a tendency to pass into one       
another2 ,heracleitus1 like his great   
successor ,hegel1 has both aspects4 ,the

 ,eleatic isolation of ,being and the   
,megarian or ,cynic isolation of        
individuals are placed in the same class
 by ,plato 7,soph472 and the same       
principle which is the symbol of motion 
to one mind is the symbol of rest to    
another4 ,the ,atomists1 who are        
sometimes regarded as the ,materialists 
of ,plato1 denied the reality of        
sensation4 ,and in the ancient as well  
as the modern world there were reactions
 from theory to experience1 from ideas  
to sense4 ,this is a point of view from 
which the philosophy of sensation       
presented great attraction to the       
ancient thinker4 ,amid the conflict of  
ideas and the variety of opinions1 the  
impression of sense remained certain and
 uniform4 ,hardness1 softness1 cold1    
heat1 etc4 are not absolutely the same  
to different persons1 but the art of    
measuring could at any rate reduce them 
all to definite natures 7,republic74    
,thus the doctrine that knowledge is    
perception supplies or seems to supply a

 firm standing ground4 ,like the other  
notions of the earlier ,greek           
philosophy1 it was held in a very simple
 way1 without much basis of reasoning1  
and without suggesting the questions    
which naturally arise in our own minds  
on the same subject4  7b7 ,the fixedness
 of impressions of sense furnishes a    
link of connexion between ancient and   
modern philosophy4 ,the modern thinker  
often repeats the parallel axiom1 ',all 
knowledge is experience4' ,he means to  
say that the outward and not the inward 
is both the original source and the     
final criterion of truth1 because the   
outward can be observed and analyzed2   
the inward is only known by external    
results1 and is dimly perceived by each 
man for himself4 ,in what does this     
differ from the saying of ,theaetetus8  
,chiefly in this--that the modern term  
'experience1' while implying a point of 
departure in sense and a return to      
sense1 also includes all the processes  
of reasoning and imagination which have 

intervened4 ,the necessary connexion    
between them by no means affords a      
measure of the relative degree of       
importance which is to be ascribed to   
either element4 ,for the inductive      
portion of any science may be small1 as 
in mathematics or ethics1 compared with 
that which the mind has attained by     
reasoning and reflection on a very few  
facts4  ,,ii4 ,the saying that ',all    
knowledge is sensation' is identified by
 ,plato with the ,protagorean thesis    
that ',man is the measure of all        
things4' ,the interpretation which      
,protagoras himself is supposed to give 
of these latter words is3 ',things are  
to me as they appear to me1 and to you  
as they appear to you4' ,but there      
remains still an ambiguity both in the  
text and in the explanation1 which has  
to be cleared up4 ,did ,protagoras      
merely mean to assert the relativity of 
knowledge to the human mind8 ,or did he 
mean to deny that there is an objective 
standard of truth8  ,these two questions

 have not been always clearly           
distinguished2 the relativity of        
knowledge has been sometimes confounded 
with uncertainty4 ,the untutored mind is
 apt to suppose that objects exist      
independently of the human faculties1   
because they really exist independently 
of the faculties of any individual4 ,in 
the same way1 knowledge appears to be a 
body of truths stored up in books1 which
 when once ascertained are independent  
of the discoverer4 ,further             
consideration shows us that these truths
 are not really independent of the mind2
 there is an adaptation of one to the   
other1 of the eye to the object of      
sense1 of the mind to the conception4   
,there would be no world1 if there      
neither were nor ever had been any one  
to perceive the world4 ,a slight effort 
of reflection enables us to understand  
this2 but no effort of reflection will  
enable us to pass beyond the limits of  
our own faculties1 or to imagine the    
relation or adaptation of objects to the

 mind to be different from that of which
 we have experience4 ,there are certain 
laws of language and logic to which we  
are compelled to conform1 and to which  
our ideas naturally adapt themselves2   
and we can no more get rid of them than 
we can cease to be ourselves4 ,the      
absolute and infinite1 whether explained
 as self-existence1 or as the totality  
of human thought1 or as the ,divine     
nature1 if known to us at all1 cannot   
escape from the category of relation4   
,but because knowledge is subjective or 
relative to the mind1 we are not to     
suppose that we are therefore deprived  
of any of the tests or criteria of      
truth4 ,one man still remains wiser than
 another1 a more accurate observer and  
relater of facts1 a truer measure of the
 proportions of knowledge4 ,the nature  
of testimony is not altered1 nor the    
verification of causes by prescribed    
methods less certain4 ,again1 the truth 
must often come to a man through others1
 according to the measure of his        

capacity and education4 ,but neither    
does this affect the testimony1 whether 
written or oral1 which he knows by      
experience to be trustworthy4 ,he cannot
 escape from the laws of his own mind2  
and he cannot escape from the further   
accident of being dependent for his     
knowledge on others4 ,but still this is 
no reason why he should always be in    
doubt2 of many personal1 of many        
historical and scientific facts he may  
be absolutely assured4 ,and having such 
a mass of acknowledged truth in the     
mathematical and physical1 not to speak 
of the moral sciences1 the moderns have 
certainly no reason to acquiesce in the 
statement that truth is appearance only1
 or that there is no difference between 
appearance and truth4  ,the relativity  
of knowledge is a truism to us1 but was 
a great psychological discovery in the  
fifth century before ,christ4 ,of this  
discovery1 the first distinct assertion 
is contained in the thesis of           
,protagoras4 ,probably he had no        

intention either of denying or affirming
 an objective standard of truth4 ,he did
 not consider whether man in the higher 
or man in the lower sense was a 'measure
 of all things4' ,like other great      
thinkers1 he was absorbed with one idea1
 and that idea was the absoluteness of  
perception4 ,like ,socrates1 he seemed  
to see that philosophy must be brought  
back from 'nature' to 'truth1' from the 
world to man4 ,but he did not stop to   
analyze whether he meant 'man' in the   
concrete or man in the abstract1 any man
 or some men1 'quod semper quod ubique' 
or individual private judgment4 ,such an
 analysis lay beyond his sphere of      
thought2 the age before ,socrates had   
not arrived at these distinctions4 ,like
 the ,cynics1 again1 he discarded       
knowledge in any higher sense than      
perception4 ,for 'truer' or 'wiser' he  
substituted the word 'better1' and is   
not unwilling to admit that both states 
and individuals are capable of practical
 improvement4 ,but this improvement does

 not arise from intellectual            
enlightenment1 nor yet from the exertion
 of the will1 but from a change of      
circumstances and impressions2 and he   
who can effect this change in himself or
 others may be deemed a philosopher4 ,in
 the mode of effecting it1 while        
agreeing with ,socrates and the ,cynics 
in the importance which he attaches to  
practical life1 he is at variance with  
both of them4 ,to suppose that practice 
can be divorced from speculation1 or    
that we may do good without caring about
 truth1 is by no means singular1 either 
in philosophy or life4 ,the singularity 
of this1 as of some other 7so-called7   
sophistical doctrines1 is the frankness 
with which they are avowed1 instead of  
being veiled1 as in modern times1 under 
ambiguous and convenient phrases4       
,plato appears to treat ,protagoras much
 as he himself is treated by ,aristotle2
 that is to say1 he does not attempt to 
understand him from his own point of    
view4 ,but he entangles him in the      

meshes of a more advanced logic4 ,to    
which ,protagoras is supposed to reply  
by ,megarian quibbles1 which destroy    
logic1 ',not only man1 but each man1 and
 each man at each moment4' ,in the      
arguments about sight and memory there  
is a palpable unfairness which is worthy
 of the great 'brainless brothers1'     
,euthydemus and ,dionysodorus1 and may  
be compared with the egkekalummenos     
7'obvelatus'7 of ,eubulides4 ,for he who
 sees with one eye only cannot be truly 
said both to see and not to see2 nor is 
memory1 which is liable to forget1 the  
immediate knowledge to which ,protagoras
 applies the term4 ,theodorus justly    
charges ,socrates with going beyond the 
truth2 and ,protagoras has equally right
 on his side when he protests against   
,socrates arguing from the common use of
 words1 which 'the vulgar pervert in all
 manner of ways4'  ,,iii4 ,the theory of
 ,protagoras is connected by ,aristotle 
as well as ,plato with the flux of      
,heracleitus4 ,but ,aristotle is only   

following ,plato1 and ,plato1 as we have
 already seen1 did not mean to imply    
that such a connexion was admitted by   
,protagoras himself4 ,his metaphysical  
genius saw or seemed to see a common    
tendency in them1 just as the modern    
historian of ancient philosophy might   
perceive a parallelism between two      
thinkers of which they were probably    
unconscious themselves4 ,we must        
remember throughout that ,plato is not  
speaking of ,heracleitus1 but of the    
,heracliteans1 who succeeded him2 nor of
 the great original ideas of the master1
 but of the ,eristic into which they had
 degenerated a hundred years later4     
,there is nothing in the fragments of   
,heracleitus which at all justifies     
,plato's account of him4 ,his philosophy
 may be resolved into two               
elements--first1 change1 secondly1 law  
or measure pervading the change3 these  
he saw everywhere1 and often expressed  
in strange mythological symbols4 ,but he
 has no analysis of sensible perception 

such as ,plato attributes to him2 nor is
 there any reason to suppose that he    
pushed his philosophy into that absolute
 negation in which ,heracliteanism was  
sunk in the age of ,plato4 ,he never    
said that 'change means every sort of   
change2' and he expressly distinguished 
between 'the general and particular     
understanding4' ,like a poet1 he        
surveyed the elements of mythology1     
nature1 thought1 which lay before him1  
and sometimes by the light of genius he 
saw or seemed to see a mysterious       
principle working behind them4 ,but as  
has been the case with other great      
philosophers1 and with ,plato and       
,aristotle themselves1 what was really  
permanent and original could not be     
understood by the next generation1 while
 a perverted logic carried out his      
chance expressions with an illogical    
consistency4 ,his simple and noble      
thoughts1 like those of the great       
,eleatic1 soon degenerated into a mere  
strife of words4 ,and when thus reduced 

to mere words1 they seem to have        
exercised a far wider influence in the  
cities of ,ionia 7where the people 'were
 mad about them'7 than in the life-time 
of ,heracleitus--a phenomenon which1    
though at first sight singular1 is not  
without a parallel in the history of    
philosophy and theology4  ,it is this   
perverted form of the ,heraclitean      
philosophy which is supposed to effect  
the final overthrow of ,protagorean     
sensationalism4 ,for if all things are  
changing at every moment1 in all sorts  
of ways1 then there is nothing fixed or 
defined at all1 and therefore no        
sensible perception1 nor any true word  
by which that or anything else can be   
described4 ,of course ,protagoras would 
not have admitted the justice of this   
argument any more than ,heracleitus     
would have acknowledged the 'uneducated 
fanatics' who appealed to his writings4 
,he might have said1 ',the excellent    
,socrates has first confused me with    
,heracleitus1 and ,heracleitus with his 

,ephesian successors1 and has then      
disproved the existence both of         
knowledge and sensation4 ,but ,i am not 
responsible for what ,i never said1 nor 
will ,i admit that my common-sense      
account of knowledge can be overthrown  
by unintelligible ,heraclitean          
paradoxes4'  ,,iv4 ,still at the bottom 
of the arguments there remains a truth1 
that knowledge is something more than   
sensible perception2--this alone would  
not distinguish man from a tadpole4 ,the
 absoluteness of sensations at each     
moment destroys the very consciousness  
of sensations 7compare ,phileb471 or the
 power of comparing them4 ,the senses   
are not mere holes in a ',trojan horse1'
 but the organs of a presiding nature1  
in which they meet4 ,a great advance has
 been made in psychology when the senses
 are recognized as organs of sense1 and 
we are admitted to see or feel 'through 
them' and not 'by them1' a distinction  
of words which1 as ,socrates observes1  
is by no means pedantic4 ,a still       

further step has been made when the most
 abstract notions1 such as ,being and   
,not-being1 sameness and difference1    
unity and plurality1 are acknowledged to
 be the creations of the mind herself1  
working upon the feelings or impressions
 of sense4 ,in this manner ,plato       
describes the process of acquiring them1
 in the words ',knowledge consists not  
in the feelings or affections           
7pathemasi71 but in the process of      
reasoning about them 7sullogismo74'     
,here1 is in the ,parmenides1 he means  
something not really different from     
generalization4 ,as in the ,sophist1 he 
is laying the foundation of a rational  
psychology1 which is to supersede the   
,platonic reminiscence of ,ideas as well
 as the ,eleatic ,being and the         
individualism of ,megarians and ,cynics4
  ,v4 ,having rejected the doctrine that
 ',knowledge is perception1' we now     
proceed to look for a definition of     
knowledge in the sphere of opinion4 ,but
 here we are met by a singular          

difficulty3 ,how is false opinion       
possible8 ,for we must either know or   
not know that which is presented to the 
mind or to sense4 ,we of course should  
answer at once3 ',no2 the alternative is
 not necessary1 for there may be degrees
 of knowledge2 and we may know and have 
forgotten1 or we may be learning1 or we 
may have a general but not a particular 
knowledge1 or we may know but not be    
able to explain2' and many other ways   
may be imagined in which we know and do 
not know at the same time4 ,but these   
answers belong to a later stage of      
metaphysical discussion2 whereas the    
difficulty in question naturally arises 
owing to the childhood of the human     
mind1 like the parallel difficulty      
respecting ,not-being4 ,men had only    
recently arrived at the notion of       
opinion2 they could not at once define  
the true and pass beyond into the false4
 ,the very word doxa was full of        
ambiguity1 being sometimes1 as in the   
,eleatic philosophy1 applied to the     

sensible world1 and again used in the   
more ordinary sense of opinion4 ,there  
is no connexion between sensible        
appearance and probability1 and yet both
 of them met in the word doxa1 and could
 hardly be disengaged from one another  
in the mind of the ,greek living in the 
fifth or fourth century ,b4,c4 ,to this 
was often added1 as at the end of the   
fifth book of the ,republic1 the idea of
 relation1 which is equally distinct    
from either of them2 also a fourth      
notion1 the conclusion of the           
dialectical process1 the making up of   
the mind after she has been 'talking to 
herself' 7,theat474  ,we are not then   
surprised that the sphere of opinion and
 of ,not-being should be a dusky1       
half-lighted place 7,republic71         
belonging neither to the old world of   
sense and imagination1 nor to the new   
world of reflection and reason4 ,plato  
attempts to clear up this darkness4 ,in 
his accustomed manner he passes from the
 lower to the higher1 without omitting  

the intermediate stages4 ,this appears  
to be the reason why he seeks for the   
definition of knowledge first in the    
sphere of opinion4 ,hereafter we shall  
find that something more than opinion is
 required4  ,false opinion is explained 
by ,plato at first as a confusion of    
mind and sense1 which arises when the   
impression on the mind does not         
correspond to the impression made on the
 senses4 ,it is obvious that this       
explanation 7supposing the distinction  
between impressions on the mind and     
impressions on the senses to be         
admitted7 does not account for all forms
 of error2 and ,plato has excluded      
himself from the consideration of the   
greater number1 by designedly omitting  
the intermediate processes of learning  
and forgetting2 nor does he include     
fallacies in the use of language or     
erroneous inferences4 ,but he is struck 
by one possibility of error1 which is   
not covered by his theory1 viz4 errors  
in arithmetic4 ,for in numbers and      

calculation there is no combination of  
thought and sense1 and yet errors may   
often happen4 ,hence he is led to       
discard the explanation which might     
nevertheless have been supposed to hold 
good 7for anything which he says to the 
contrary7 as a rationale of error1 in   
the case of facts derived from sense4   
,another attempt is made to explain     
false opinion by assigning to error a   
sort of positive existence4 ,but error  
or ignorance is essentially negative--a 
not-knowing2 if we knew an error1 we    
should be no longer in error4 ,we may   
veil our difficulty under figures of    
speech1 but these1 although telling     
arguments with the multitude1 can never 
be the real foundation of a system of   
psychology4 ,only they lead us to dwell 
upon mental phenomena which if expressed
 in an abstract form would not be       
realized by us at all4 ,the figure of   
the mind receiving impressions is one of
 those images which have rooted         
themselves for ever in language4 ,it may

 or may not be a 'gracious aid' to      
thought2 but it cannot be got rid of4   
,the other figure of the enclosure is   
also remarkable as affording the first  
hint of universal all-pervading         
ideas1--a notion further carried out in 
the ,sophist4 ,this is implied in the   
birds1 some in flocks1 some solitary1   
which fly about anywhere and everywhere4
 ,plato discards both figures1 as not   
really solving the question which to us 
appears so simple3 ',how do we make     
mistakes8' ,the failure of the enquiry  
seems to show that we should return to  
knowledge1 and begin with that2 and we  
may afterwards proceed1 with a better   
hope of success1 to the examination of  
opinion4  ,but is true opinion really   
distinct from knowledge8 ,the difference
 between these he seeks to establish by 
an argument1 which to us appears        
singular and unsatisfactory4 ,the       
existence of true opinion is proved by  
the rhetoric of the law courts1 which   
cannot give knowledge1 but may give true

 opinion4 ,the rhetorician cannot put   
the judge or juror in possession of all 
the facts which prove an act of         
violence1 but he may truly persuade them
 of the commission of such an act4 ,here
 the idea of true opinion seems to be a 
right conclusion from imperfect         
knowledge4 ,but the correctness of such 
an opinion will be purely accidental2   
and is really the effect of one man1 who
 has the means of knowing1 persuading   
another who has not4 ,plato would have  
done better if he had said that true    
opinion was a contradiction in terms4   
,assuming the distinction between       
knowledge and opinion1 ,theaetetus1 in  
answer to ,socrates1 proceeds to define 
knowledge as true opinion1 with definite
 or rational explanation4 ,this         
,socrates identifies with another and   
different theory1 of those who assert   
that knowledge first begins with a      
proposition4  ,the elements may be      
perceived by sense1 but they are names1 
and cannot be defined4 ,when we assign  

to them some predicate1 they first begin
 to have a meaning 7onomaton sumploke   
logou ousia74 ,this seems equivalent to 
saying1 that the individuals of sense   
become the subject of knowledge when    
they are regarded as they are in nature 
in relation to other individuals4  ,yet 
we feel a difficulty in following this  
new hypothesis4 ,for must not opinion be
 equally expressed in a proposition8    
,the difference between true and false  
opinion is not the difference between   
the particular and the universal1 but   
between the true universal and the      
false4 ,thought may be as much at fault 
as sight4 ,when we place individuals    
under a class1 or assign to them        
attributes1 this is not knowledge1 but a
 very rudimentary process of thought2   
the first generalization of all1 without
 which language would be impossible4    
,and has ,plato kept altogether clear of
 a confusion1 which the analogous word  
logos tends to create1 of a proposition 
and a definition8 ,and is not the       

confusion increased by the use of the   
analogous term 'elements1' or 'letters'8
 ,for there is no real resemblance      
between the relation of letters to a    
syllable1 and of the terms to a         
proposition4  ,plato1 in the spirit of  
the ,megarian philosophy1 soon discovers
 a flaw in the explanation4 ,for how can
 we know a compound of which the simple 
elements are unknown to us8 ,can two    
unknowns make a known8 ,can a whole be  
something different from the parts8 ,the
 answer of experience is that they can2 
for we may know a compound1 which we are
 unable to analyze into its elements2   
and all the parts1 when united1 may be  
more than all the parts separated3 e4g4 
the number four1 or any other number1 is
 more than the units which are contained
 in it2 any chemical compound is more   
than and different from the simple      
elements4 ,but ancient philosophy in    
this1 as in many other instances1       
proceeding by the path of mental        
analysis1 was perplexed by doubts which 

warred against the plainest facts4      
,three attempts to explain the new      
definition of knowledge still remain to 
be considered4 ,they all of them turn on
 the explanation of logos4 ,the first   
account of the meaning of the word is   
the reflection of thought in speech--a  
sort of nominalism ',la science est une 
langue bien faite4' ,but anybody who is 
not dumb can say what he thinks2        
therefore mere speech cannot be         
knowledge4 ,and yet we may observe1 that
 there is in this explanation an element
 of truth which is not recognized by    
,plato2 viz4 that truth and thought are 
inseparable from language1 although mere
 expression in words is not truth4 ,the 
second explanation of logos is the      
enumeration of the elementary parts of  
the complex whole4 ,but this is only    
definition accompanied with right       
opinion1 and does not yet attain to the 
certainty of knowledge4 ,plato does not 
mention the greater objection1 which is1
 that the enumeration of particulars is 

endless2 such a definition would be     
based on no principle1 and would not    
help us at all in gaining a common idea4
 ,the third is the best                 
explanation1--the possession of a       
characteristic mark1 which seems to     
answer to the logical definition by     
genus and difference4 ,but this1 again1 
is equally necessary for right opinion2 
and we have already determined1 although
 not on very satisfactory grounds1 that 
knowledge must be distinguished from    
opinion4 ,a better distinction is drawn 
between them in the ,timaeus4 ,they     
might be opposed as philosophy and      
rhetoric1 and as conversant respectively
 with necessary and contingent matter4  
,but no true idea of the nature of      
either of them1 or of their relation to 
one another1 could be framed until      
science obtained a content4 ,the ancient
 philosophers in the age of ,plato      
thought of science only as pure         
abstraction1 and to this opinion stood  
in no relation4  ,like ,theaetetus1 we  

have attained to no definite result4    
,but an interesting phase of ancient    
philosophy has passed before us4 ,and   
the negative result is not to be        
despised4 ,for on certain subjects1 and 
in certain states of knowledge1 the work
 of negation or clearing the ground must
 go on1 perhaps for a generation1 before
 the new structure can begin to rise4   
,plato saw the necessity of combating   
the illogical logic of the ,megarians   
and ,eristics4 ,for the completion of   
the edifice1 he makes preparation in the
 ,theaetetus1 and crowns the work in the
 ,sophist4  ,many 7#a7 fine expressions1
 and 7#b7 remarks full of wisdom1 7#c7  
also germs of a metaphysic of the       
future1 are scattered up and down in the
 dialogue4 ,such1 for example1 as 7#a7  
the comparison of ,theaetetus' progress 
in learning to the 'noiseless flow of a 
river of oil'2 the satirical touch1     
'flavouring a sauce or fawning speech'2 
or the remarkable expression1 'full of  
impure dialectic'2 or the lively images 

under which the argument is             
described1--'the flood of arguments     
pouring in1' the fresh discussions      
'bursting in like a band of revellers4' 
7#b7 ,as illustrations of the second    
head1 may be cited the remark of        
,socrates1 that 'distinctions of words1 
although sometimes pedantic1 are also   
necessary'2 or the fine touch in the    
character of the lawyer1 that 'dangers  
came upon him when the tenderness of    
youth was unequal to them'2 or the      
description of the manner in which the  
spirit is broken in a wicked man who    
listens to reproof until he becomes like
 a child2 or the punishment of the      
wicked1 which is not physical suffering1
 but the perpetual companionship of evil
 7compare ,gorgias72 or the saying1     
often repeated by ,aristotle and others1
 that 'philosophy begins in wonder1 for 
,iris is the child of ,thaumas'2 or the 
superb contempt with which the          
philosopher takes down the pride of     
wealthy landed proprietors by comparison

 of the whole earth4 7#c7 ,important    
metaphysical ideas are3 a4 the          
conception of thought1 as the mind      
talking to herself2 b4 the notion of a  
common sense1 developed further by      
,aristotle1 and the explicit            
declaration1 that the mind gains her    
conceptions of ,being1 sameness1 number1
 and the like1 from reflection on       
herself2 c4 the excellent distinction of
 ,theaetetus 7which ,socrates1 speaking 
with emphasis1 'leaves to grow'7 between
 seeing the forms or hearing the sounds 
of words in a foreign language1 and     
understanding the meaning of them2 and  
d4 the distinction of ,socrates himself 
between 'having' and 'possessing'       
knowledge1 in which the answer to the   
whole discussion appears to be          
contained4  444  ,there is a difference 
between ancient and modern psychology1  
and we have a difficulty in explaining  
one in the terms of the other4 ,to us   
the inward and outward sense and the    
inward and outward worlds of which they 

are the organs are parted by a wall1 and
 appear as if they could never be       
confounded4 ,the mind is endued with    
faculties1 habits1 instincts1 and a     
personality or consciousness in which   
they are bound together4 ,over against  
these are placed forms1 colours1        
external bodies coming into contact with
 our own body4 ,we speak of a subject   
which is ourselves1 of an object which  
is all the rest4 ,these are separable in
 thought1 but united in any act of      
sensation1 reflection1 or volition4 ,as 
there are various degrees in which the  
mind may enter into or be abstracted    
from the operations of sense1 so there  
are various points at which this        
separation or union may be supposed to  
occur4 ,and within the sphere of mind   
the analogy of sense reappears2 and we  
distinguish not only external objects1  
but objects of will and of knowledge    
which we contrast with them4 ,these     
again are comprehended in a higher      
object1 which reunites with the subject4

 ,a multitude of abstractions are       
created by the efforts of successive    
thinkers which become logical           
determinations2 and they have to be     
arranged in order1 before the scheme of 
thought is complete4 ,the framework of  
the human intellect is not the peculium 
of an individual1 but the joint work of 
many who are of all ages and countries4 
,what we are in mind is due1 not merely 
to our physical1 but to our mental      
antecedents which we trace in history1  
and more especially in the history of   
philosophy4 ,nor can mental phenomena be
 truly explained either by physiology or
 by the observation of consciousness    
apart from their history4 ,they have a  
growth of their own1 like the growth of 
a flower1 a tree1 a human being4 ,they  
may be conceived as of themselves       
constituting a common mind1 and having a
 sort of personal identity in which they
 coexist4  ,so comprehensive is modern  
psychology1 seeming to aim at           
constructing anew the entire world of   

thought4 ,and prior to or simultaneously
 with this construction a negative      
process has to be carried on1 a clearing
 away of useless abstractions which we  
have inherited from the past4 ,many     
erroneous conceptions of the mind       
derived from former philosophies have   
found their way into language1 and we   
with difficulty disengage ourselves from
 them4 ,mere figures of speech have     
unconsciously influenced the minds of   
great thinkers4 ,also there are some    
distinctions1 as1 for example1 that of  
the will and of the reason1 and of the  
moral and intellectual faculties1 which 
are carried further than is justified by
 experience4 ,any separation of things  
which we cannot see or exactly define1  
though it may be necessary1 is a fertile
 source of error4 ,the division of the  
mind into faculties or powers or virtues
 is too deeply rooted in language to be 
got rid of1 but it gives a false        
impression4 ,for if we reflect on       
ourselves we see that all our faculties 

easily pass into one another1 and are   
bound together in a single mind or      
consciousness2 but this mental unity is 
apt to be concealed from us by the      
distinctions of language4  ,a profusion 
of words and ideas has obscured rather  
than enlightened mental science4 ,it is 
hard to say how many fallacies have     
arisen from the representation of the   
mind as a box1 as a 'tabula rasa1' a    
book1 a mirror1 and the like4 ,it is    
remarkable how ,plato in the            
,theaetetus1 after having indulged in   
the figure of the waxen tablet and the  
decoy1 afterwards discards them4 ,the   
mind is also represented by another     
class of images1 as the spring of a     
watch1 a motive power1 a breath1 a      
stream1 a succession of points or       
moments4 ,as ,plato remarks in the      
,cratylus1 words expressive of motion as
 well as of rest are employed to        
describe the faculties and operations of
 the mind2 and in these there is        
contained another store of fallacies4   

,some shadow or reflection of the body  
seems always to adhere to our thoughts  
about ourselves1 and mental processes   
are hardly distinguished in language    
from bodily ones4 ,to see or perceive   
are used indifferently of both2 the     
words intuition1 moral sense1 common    
sense1 the mind's eye1 are figures of   
speech transferred from one to the      
other4 ,and many other words used in    
early poetry or in sacred writings to   
express the works of mind have a        
materialistic sound2 for old mythology  
was allied to sense1 and the distinction
 of matter and mind had not as yet      
arisen4 ,thus materialism receives an   
illusive aid from language2 and both in 
philosophy and religion the imaginary   
figure or association easily takes the  
place of real knowledge4  ,again1 there 
is the illusion of looking into our own 
minds as if our thoughts or feelings    
were written down in a book4 ,this is   
another figure of speech1 which might be
 appropriately termed 'the fallacy of   

the looking-glass4' ,we cannot look at  
the mind unless we have the eye which   
sees1 and we can only look1 not into1   
but out of the mind at the thoughts1    
words1 actions of ourselves and others4 
,what we dimly recognize within us is   
not experience1 but rather the          
suggestion of an experience1 which we   
may gather1 if we will1 from the        
observation of the world4 ,the memory   
has but a feeble recollection of what we
 were saying or doing a few weeks or a  
few months ago1 and still less of what  
we were thinking or feeling4 ,this is   
one among many reasons why there is so  
little self-knowledge among mankind2    
they do not carry with them the thought 
of what they are or have been4 ,the     
so-called 'facts of consciousness' are  
equally evanescent2 they are facts which
 nobody ever saw1 and which can neither 
be defined nor described4 ,of the three 
laws of thought the first 7,all ,a  ,a7 
is an identical proposition--that is to 
say1 a mere word or symbol claiming to  

be a proposition3 the two others        
7,nothing can be ,a and not ,a1 and     
,everything is either ,a or not ,a7 are 
untrue1 because they exclude degrees and
 also the mixed modes and double aspects
 under which truth is so often presented
 to us4 ,to assert that man is man is   
unmeaning2 to say that he is free or    
necessary and cannot be both is a half  
truth only4 ,these are a few of the     
entanglements which impede the natural  
course of human thought4 ,lastly1 there 
is the fallacy which lies still deeper1 
of regarding the individual mind apart  
from the universal1 or either1 as a     
self-existent entity apart from the     
ideas which are contained in them4  ,in 
ancient philosophies the analysis of the
 mind is still rudimentary and          
imperfect4 ,it naturally began with an  
effort to disengage the universal from  
sense--this was the first lifting up of 
the mist4 ,it wavered between object and
 subject1 passing imperceptibly from one
 or ,being to mind and thought4         

,appearance in the outward object was   
for a time indistinguishable from       
opinion in the subject4 ,at length      
mankind spoke of knowing as well as of  
opining or perceiving4 ,but when the    
word 'knowledge' was found how was it to
 be explained or defined8 ,it was not an
 error1 it was a step in the right      
direction1 when ,protagoras said that   
',man is the measure of all things1' and
 that ',all knowledge is perception4'   
,this was the subjective which          
corresponded to the objective ',all is  
flux4' ,but the thoughts of men         
deepened1 and soon they began to be     
aware that knowledge was neither sense1 
nor yet opinion--with or without        
explanation2 nor the expression of      
thought1 nor the enumeration of parts1  
nor the addition of characteristic      
marks4 ,motion and rest were equally ill
 adapted to express its nature1 although
 both must in some sense be attributed  
to it2 it might be described more truly 
as the mind conversing with herself2 the

 discourse of reason2 the hymn of       
dialectic1 the science of relations1 of 
ideas1 of the so-called arts and        
sciences1 of the one1 of the good1 of   
the all3--this is the way along which   
,plato is leading us in his later       
dialogues4 ,in its higher signification 
it was the knowledge1 not of men1 but of
 gods1 perfect and all sufficing3--like 
other ideals always passing out of      
sight1 and nevertheless present to the  
mind of ,aristotle as well as ,plato1   
and the reality to which they were both 
tending4 ,for ,aristotle as well as     
,plato would in modern phraseology have 
been termed a mystic2 and like him would
 have defined the higher philosophy to  
be ',knowledge of being or              
essence1'--words to which in our own day
 we have a difficulty in attaching a    
meaning4  ,yet1 in spite of ,plato and  
his followers1 mankind have again and   
again returned to a sensational         
philosophy4 ,as to some of the early    
thinkers1 amid the fleetings of sensible

 objects1 ideas alone seemed to be      
fixed1 so to a later generation amid the
 fluctuation of philosophical opinions  
the only fixed points appeared to be    
outward objects4 ,any pretence of       
knowledge which went beyond them implied
 logical processes1 of the correctness  
of which they had no assurance and which
 at best were only probable4 ,the mind1 
tired of wandering1 sought to rest on   
firm ground2 when the idols of          
philosophy and language were stripped   
off1 the perception of outward objects  
alone remained4 ,the ancient ,epicureans
 never asked whether the comparison of  
these with one another did not involve  
principles of another kind which were   
above and beyond them4 ,in like manner  
the modern inductive philosophy forgot  
to enquire into the meaning of          
experience1 and did not attempt to form 
a conception of outward objects apart   
from the mind1 or of the mind apart from
 them4 ,soon objects of sense were      
merged in sensations and feelings1 but  

feelings and sensations were still      
unanalyzed4 ,at last we return to the   
doctrine attributed by ,plato to        
,protagoras1 that the mind is only a    
succession of momentary perceptions4 ,at
 this point the modern philosophy of    
experience forms an alliance with       
ancient scepticism4  ,the higher truths 
of philosophy and religion are very far 
removed from sense4 ,admitting that1    
like all other knowledge1 they are      
derived from experience1 and that       
experience is ultimately resolvable into
 facts which come to us through the eye 
and ear1 still their origin is a mere   
accident which has nothing to do with   
their true nature4 ,they are universal  
and unseen2 they belong to all          
times--past1 present1 and future4 ,any  
worthy notion of mind or reason includes
 them4 ,the proof of them is1 #ast1     
their comprehensiveness and consistency 
with one another2 #bndly1 their         
agreement with history and experience4  
,but sensation is of the present only1  

is isolated1 is and is not in successive
 moments4 ,it takes the passing hour as 
it comes1 following the lead of the eye 
or ear instead of the command of reason4
 ,it is a faculty which man has in      
common with the animals1 and in which he
 is inferior to many of them4 ,the      
importance of the senses in us is that  
they are the apertures of the mind1     
doors and windows through which we take 
in and make our own the materials of    
knowledge4 ,regarded in any other point 
of view sensation is of all mental acts 
the most trivial and superficial4 ,hence
 the term 'sensational' is rightly used 
to express what is shallow in thought   
and feeling4  ,we propose in what       
follows1 first of all1 like ,plato in   
the ,theaetetus1 to analyse sensation1  
and secondly to trace the connexion     
between theories of sensation and a     
sensational or ,epicurean philosophy4   
,paragraph ,i4 ,we1 as well as the      
ancients1 speak of the five senses1 and 
of a sense1 or common sense1 which is   

the abstraction of them4 ,the term      
'sense' is also used metaphorically1    
both in ancient and modern philosophy1  
to express the operations of the mind   
which are immediate or intuitive4 ,of   
the five senses1 two--the sight and the 
hearing--are of a more subtle and       
complex nature1 while two others--the   
smell and the taste--seem to be only    
more refined varieties of touch4 ,all of
 them are passive1 and by this are      
distinguished from the active faculty of
 speech3 they receive impressions1 but  
do not produce them1 except in so far as
 they are objects of sense themselves4  
,physiology speaks to us of the         
wonderful apparatus of nerves1 muscles1 
tissues1 by which the senses are enabled
 to fulfil their functions4 ,it traces  
the connexion1 though imperfectly1 of   
the bodily organs with the operations of
 the mind4 ,of these latter1 it seems   
rather to know the conditions than the  
causes4 ,it can prove to us that without
 the brain we cannot think1 and that    

without the eye we cannot see3 and yet  
there is far more in thinking and seeing
 than is given by the brain and the eye4
 ,it observes the 'concomitant          
variations' of body and mind4           
,psychology1 on the other hand1 treats  
of the same subject regarded from       
another point of view4 ,it speaks of the
 relation of the senses to one another2 
it shows how they meet the mind2 it     
analyzes the transition from sense to   
thought4 ,the one describes their nature
 as apparent to the outward eye2 by the 
other they are regarded only as the     
instruments of the mind4 ,it is in this 
latter point of view that we propose to 
consider them4  ,the simplest sensation 
involves an unconscious or nascent      
operation of the mind2 it implies       
objects of sense1 and objects of sense  
have differences of form1 number1       
colour4 ,but the conception of an object
 without us1 or the power of            
discriminating numbers1 forms1 colours1 
is not given by the sense1 but by the   

mind4 ,a mere sensation does not attain 
to distinctness3 it is a confused       
impression1 sugkechumenon ti1 as ,plato 
says 7,republic71 until number          
introduces light and order into the     
confusion4 ,at what point confusion     
becomes distinctness is a question of   
degree which cannot be precisely        
determined4 ,the distant object1 the    
undefined notion1 come out into relief  
as we approach them or attend to them4  
,or we may assist the analysis by       
attempting to imagine the world first   
dawning upon the eye of the infant or of
 a person newly restored to sight4 ,yet 
even with them the mind as well as the  
eye opens or enlarges4 ,for all three   
are inseparably bound together--the     
object would be nowhere and nothing1 if 
not perceived by the sense1 and the     
sense would have no power of            
distinguishing without the mind4  ,but  
prior to objects of sense there is a    
third nature in which they are          
contained--that is to say1 space1 which 

may be explained in various ways4 ,it is
 the element which surrounds them2 it is
 the vacuum or void which they leave or 
occupy when passing from one portion of 
space to another4 ,it might be described
 in the language of ancient philosophy1 
as 'the ,not-being' of objects4 ,it is a
 negative idea which in the course of   
ages has become positive4 ,it is        
originally derived from the             
contemplation of the world without      
us--the boundless earth or sea1 the     
vacant heaven1 and is therefore acquired
 chiefly through the sense of sight3 to 
the blind the conception of space is    
feeble and inadequate1 derived for the  
most part from touch or from the        
descriptions of others4 ,at first it    
appears to be continuous2 afterwards we 
perceive it to be capable of division by
 lines or points1 real or imaginary4 ,by
 the help of mathematics we form another
 idea of space1 which is altogether     
independent of experience4 ,geometry    
teaches us that the innumerable lines   

and figures by which space is or may be 
intersected are absolutely true in all  
their combinations and consequences4    
,new and unchangeable properties of     
space are thus developed1 which are     
proved to us in a thousand ways by      
mathematical reasoning as well as by    
common experience4 ,through quantity and
 measure we are conducted to our        
simplest and purest notion of matter1   
which is to the cube or solid what space
 is to the square or surface4 ,and all  
our applications of mathematics are     
applications of our ideas of space to   
matter4 ,no wonder then that they seem  
to have a necessary existence to us4    
,being the simplest of our ideas1 space 
is also the one of which we have the    
most difficulty in ridding ourselves4   
,neither can we set a limit to it1 for  
wherever we fix a limit1 space is       
springing up beyond4 ,neither can we    
conceive a smallest or indivisible      
portion of it2 for within the smallest  
there is a smaller still2 and even these

 inconceivable qualities of space1      
whether the infinite or the             
infinitesimal1 may be made the subject  
of reasoning and have a certain truth to
 us4  ,whether space exists in the mind 
or out of it1 is a question which has no
 meaning4 ,we should rather say that    
without it the mind is incapable of     
conceiving the body1 and therefore of   
conceiving itself4 ,the mind may be     
indeed imagined to contain the body1 in 
the same way that ,aristotle 7partly    
following ,plato7 supposes ,god to be   
the outer heaven or circle of the       
universe4 ,but how can the individual   
mind carry about the universe of space  
packed up within1 or how can separate   
minds have either a universe of their   
own or a common universe8 ,in such      
conceptions there seems to be a         
confusion of the individual and the     
universal4 ,to say that we can only have
 a true idea of ourselves when we deny  
the reality of that by which we have any
 idea of ourselves is an absurdity4 ,the

 earth which is our habitation and 'the 
starry heaven above' and we ourselves   
are equally an illusion1 if space is    
only a quality or condition of our      
minds4  ,again1 we may compare the      
truths of space with other truths       
derived from experience1 which seem to  
have a necessity to us in proportion to 
the frequency of their recurrence or the
 truth of the consequences which may be 
inferred from them4 ,we are thus led to 
remark that the necessity in our ideas  
of space on which much stress has been  
laid1 differs in a slight degree only   
from the necessity which appears to     
belong to other of our ideas1 e4g4      
weight1 motion1 and the like4 ,and there
 is another way in which this necessity 
may be explained4 ,we have been taught  
it1 and the truth which we were taught  
or which we inherited has never been    
contradicted in all our experience and  
is therefore confirmed by it4 ,who can  
resist an idea which is presented to him
 in a general form in every moment of   

his life and of which he finds no       
instance to the contrary8 ,the greater  
part of what is sometimes regarded as   
the a priori intuition of space is      
really the conception of the various    
geometrical figures of which the        
properties have been revealed by        
mathematical analysis4 ,and the         
certainty of these properties is        
immeasurably increased to us by our     
finding that they hold good not only in 
every instance1 but in all the          
consequences which are supposed to flow 
from them4  ,neither must we forget that
 our idea of space1 like our other      
ideas1 has a history4 ,the ,homeric     
poems contain no word for it2 even the  
later ,greek philosophy has not the     
,kantian notion of space1 but only the  
definite 'place' or 'the infinite4' ,to 
,plato1 in the ,timaeus1 it is known    
only as the 'nurse of generation4' ,when
 therefore we speak of the necessity of 
our ideas of space we must remember that
 this is a necessity which has grown up 

with the growth of the human mind1 and  
has been made by ourselves4 ,we can free
 ourselves from the perplexities which  
are involved in it by ascending to a    
time in which they did not as yet exist4
 ,and when space or time are described  
as 'a priori forms or intuitions added  
to the matter given in sensation1' we   
should consider that such expressions   
belong really to the 'pre-historic      
study' of philosophy1 i4e4 to the       
eighteenth century1 when men sought to  
explain the human mind without regard to
 history or language or the social      
nature of man4  ,in every act of sense  
there is a latent perception of space1  
of which we only become conscious when  
objects are withdrawn from it4 ,there   
are various ways in which we may trace  
the connexion between them4 ,we may     
think of space as unresisting matter1   
and of matter as divided into objects2  
or of objects again as formed by        
abstraction into a collective notion of 
matter1 and of matter as rarefied into  

space4 ,and motion may be conceived as  
the union of there and not there in     
space1 and force as the materializing or
 solidification of motion4 ,space again 
is the individual and universal in one2 
or1 in other words1 a perception and    
also a conception4 ,so easily do what   
are sometimes called our simple ideas   
pass into one another1 and differences  
of kind resolve themselves into         
differences of degree4  ,within or      
behind space there is another           
abstraction in many respects similar to 
it--time1 the form of the inward1 as    
space is the form of the outward4 ,as we
 cannot think of outward objects of     
sense or of outward sensations without  
space1 so neither can we think of a     
succession of sensations without time4  
,it is the vacancy of thoughts or       
sensations1 as space is the void of     
outward objects1 and we can no more     
imagine the mind without the one than   
the world without the other4 ,it is to  
arithmetic what space is to geometry2   

or1 more strictly1 arithmetic may be    
said to be equally applicable to both4  
,it is defined in our minds1 partly by  
the analogy of space and partly by the  
recollection of events which have       
happened to us1 or the consciousness of 
feelings which we are experiencing4     
,like space1 it is without limit1 for   
whatever beginning or end of time we    
fix1 there is a beginning and end before
 them1 and so on without end4 ,we speak 
of a past1 present1 and future1 and     
again the analogy of space assists us in
 conceiving of them as coexistent4 ,when
 the limit of time is removed there     
arises in our minds the idea of         
eternity1 which at first1 like time     
itself1 is only negative1 but gradually1
 when connected with the world and the  
divine nature1 like the other negative  
infinity of space1 becomes positive4    
,whether time is prior to the mind and  
to experience1 or coeval with them1 is  
7like the parallel question about space7
 unmeaning4 ,like space it has been     

realized gradually3 in the ,homeric     
poems1 or even in the ,hesiodic         
cosmogony1 there is no more notion of   
time than of space4 ,the conception of  
being is more general than either1 and  
might therefore with greater            
plausibility be affirmed to be a        
condition or quality of the mind4 ,the a
 priori intuitions of ,kant would have  
been as unintelligible to ,plato as his 
a priori synthetical propositions to    
,aristotle4 ,the philosopher of         
,konigsberg supposed himself to be      
analyzing a necessary mode of thought3  
he was not aware that he was dealing    
with a mere abstraction4 ,but now that  
we are able to trace the gradual        
developement of ideas through religion1 
through language1 through abstractions1 
why should we interpose the fiction of  
time between ourselves and realities8   
,why should we single out one of these  
abstractions to be the a priori         
condition of all the others8 ,it comes  
last and not first in the order of our  

thoughts1 and is not the condition      
precedent of them1 but the last         
generalization of them4 ,nor can any    
principle be imagined more suicidal to  
philosophy than to assume that all the  
truth which we are capable of attaining 
is seen only through an unreal medium4  
,if all that exists in time is illusion1
 we may well ask with ,plato1 ',what    
becomes of the mind8'  ,leaving the a   
priori conditions of sensation we may   
proceed to consider acts of sense4      
,these admit of various degrees of      
duration or intensity2 they admit also  
of a greater or less extension from one 
object1 which is perceived directly1 to 
many which are perceived indirectly or  
in a less degree1 and to the various    
associations of the object which are    
latent in the mind4 ,in general the     
greater the intension the less the      
extension of them4 ,the simplest        
sensation implies some relation of      
objects to one another1 some position in
 space1 some relation to a previous or  

subsequent sensation4 ,the acts of      
seeing and hearing may be almost        
unconscious and may pass away unnoted2  
they may also leave an impression behind
 them or power of recalling them4 ,if1  
after seeing an object we shut our eyes1
 the object remains dimly seen in the   
same or about the same place1 but with  
form and lineaments half filled up4     
,this is the simplest act of memory4    
,and as we cannot see one thing without 
at the same time seeing another1        
different objects hang together in      
recollection1 and when we call for one  
the other quickly follows4 ,to think of 
the place in which we have last seen a  
thing is often the best way of recalling
 it to the mind4 ,hence memory is       
dependent on association4 ,the act of   
recollection may be compared to the     
sight of an object at a great distance  
which we have previously seen near and  
seek to bring near to us in thought4    
,memory is to sense as dreaming is to   
waking2 and like dreaming has a wayward 

and uncertain power of recalling        
impressions from the past4  ,thus begins
 the passage from the outward to the    
inward sense4 ,but as yet there is no   
conception of a universal--the mind only
 remembers the individual object or     
objects1 and is always attaching to them
 some colour or association of sense4   
,the power of recollection seems to     
depend on the intensity or largeness of 
the perception1 or on the strength of   
some emotion with which it is           
inseparably connected4 ,this is the     
natural memory which is allied to sense1
 such as children appear to have and    
barbarians and animals4 ,it is          
necessarily limited in range1 and its   
limitation is its strength4 ,in later   
life1 when the mind has become crowded  
with names1 acts1 feelings1 images      
innumerable1 we acquire by education    
another memory of system and arrangement
 which is both stronger and weaker than 
the first--weaker in the recollection of
 sensible impressions as they are       

represented to us by eye or             
ear--stronger by the natural connexion  
of ideas with objects or with one       
another4 ,and many of the notions which 
form a part of the train of our thoughts
 are hardly realized by us at the time1 
but1 like numbers or algebraical        
symbols1 are used as signs only1 thus   
lightening the labour of recollection4  
,and now we may suppose that numerous   
images present themselves to the mind1  
which begins to act upon them and to    
arrange them in various ways4 ,besides  
the impression of external objects      
present with us or just absent from us1 
we have a dimmer conception of other    
objects which have disappeared from our 
immediate recollection and yet continue 
to exist in us4 ,the mind is full of    
fancies which are passing to and fro    
before it4 ,some feeling or association 
calls them up1 and they are uttered by  
the lips4 ,this is the first rudimentary
 imagination1 which may be truly        
described in the language of ,hobbes1 as

 'decaying sense1' an expression which  
may be applied with equal truth to      
memory as well4 ,for memory and         
imagination1 though we sometimes oppose 
them1 are nearly allied2 the difference 
between them seems chiefly to lie in the
 activity of the one compared with the  
passivity of the other4 ,the sense      
decaying in memory receives a flash of  
light or life from imagination4         
,dreaming is a link of connexion between
 them2 for in dreaming we feebly        
recollect and also feebly imagine at one
 and the same time4 ,when reason is     
asleep the lower part of the mind       
wanders at will amid the images which   
have been received from without1 the    
intelligent element retires1 and the    
sensual or sensuous takes its place4    
,and so in the first efforts of         
imagination reason is latent or set     
aside2 and images1 in part disorderly1  
but also having a unity 7however        
imperfect7 of their own1 pour like a    
flood over the mind4 ,and if we could   

penetrate into the heads of animals we  
should probably find that their         
intelligence1 or the state of what in   
them is analogous to our intelligence1  
is of this nature4  ,thus far we have   
been speaking of men1 rather in the     
points in which they resemble animals   
than in the points in which they differ 
from them4 ,the animal too has memory in
 various degrees1 and the elements of   
imagination1 if1 as appears to be the   
case1 he dreams4 ,how far their powers  
or instincts are educated by the        
circumstances of their lives or by      
intercourse with one another or with    
mankind1 we cannot precisely tell4      
,they1 like ourselves1 have the physical
 inheritance of form1 scent1 hearing1   
sight1 and other qualities or instincts4
 ,but they have not the mental          
inheritance of thoughts and ideas handed
 down by tradition1 'the slow additions 
that build up the mind' of the human    
race4 ,and language1 which is the great 
educator of mankind1 is wanting in them2

 whereas in us language is ever         
present--even in the infant the latent  
power of naming is almost immediately   
observable4 ,and therefore the          
description which has been already given
 of the nascent power of the faculties  
is in reality an anticipation4 ,for     
simultaneous with their growth in man a 
growth of language must be supposed4    
,the child of two years old sees the    
fire once and again1 and the feeble     
observation of the same recurring object
 is associated with the feeble utterance
 of the name by which he is taught to   
call it4 ,soon he learns to utter the   
name when the object is no longer there1
 but the desire or imagination of it is 
present to him4 ,at first in every use  
of the word there is a colour of sense1 
an indistinct picture of the object     
which accompanies it4 ,but in later     
years he sees in the name only the      
universal or class word1 and the more   
abstract the notion becomes1 the more   
vacant is the image which is presented  

to him4 ,henceforward all the operations
 of his mind1 including the perceptions 
of sense1 are a synthesis of sensations1
 words1 conceptions4 ,in seeing or      
hearing or looking or listening the     
sensible impression prevails over the   
conception and the word4 ,in reflection 
the process is reversed--the outward    
object fades away into nothingness1 the 
name or the conception or both together 
are everything4 ,language1 like number1 
is intermediate between the two1        
partaking of the definiteness of the    
outer and of the universality of the    
inner world4 ,for logic teaches us that 
every word is really a universal1 and   
only condescends by the help of position
 or circumlocution to become the        
expression of individuals or            
particulars4 ,and sometimes by using    
words as symbols we are able to give a  
'local habitation and a name' to the    
infinite and inconceivable4  ,thus we   
see that no line can be drawn between   
the powers of sense and of              

reflection--they pass imperceptibly into
 one another4 ,we may indeed distinguish
 between the seeing and the closed      
eye--between the sensation and the      
recollection of it4 ,but this           
distinction carries us a very little    
way1 for recollection is present in     
sight as well as sight in recollection4 
,there is no impression of sense which  
does not simultaneously recall          
differences of form1 number1 colour1 and
 the like4 ,neither is such a           
distinction applicable at all to our    
internal bodily sensations1 which give  
no sign of themselves when unaccompanied
 with pain1 and even when we are most   
conscious of them1 have often no        
assignable place in the human frame4    
,who can divide the nerves or great     
nervous centres from the mind which uses
 them8 ,who can separate the pains and  
pleasures of the mind from the pains and
 pleasures of the body8 ,the words      
'inward and outward1' 'active and       
passive1' 'mind and body1' are best     

conceived by us as differences of degree
 passing into differences of kind1 and  
at one time and under one aspect acting 
in harmony and then again opposed4 ,they
 introduce a system and order into the  
knowledge of our being2 and yet1 like   
many other general terms1 are often in  
advance of our actual analysis or       
observation4  ,according to some writers
 the inward sense is only the fading    
away or imperfect realization of the    
outward4 ,but this leaves out of sight  
one half of the phenomenon4 ,for the    
mind is not only withdrawn from the     
world of sense but introduced to a      
higher world of thought and reflection1 
in which1 like the outward sense1 she is
 trained and educated4 ,by use the      
outward sense becomes keener and more   
intense1 especially when confined within
 narrow limits4 ,the savage with little 
or no thought has a quicker discernment 
of the track than the civilised man2 in 
like manner the dog1 having the help of 
scent as well as of sight1 is superior  

to the savage4 ,by use again the inward 
thought becomes more defined and        
distinct2 what was at first an effort is
 made easy by the natural               
instrumentality of language1 and the    
mind learns to grasp universals with no 
more exertion than is required for the  
sight of an outward object4 ,there is a 
natural connexion and arrangement of    
them1 like the association of objects in
 a landscape4 ,just as a note or two of 
music suffices to recall a whole piece  
to the musician's or composer's mind1 so
 a great principle or leading thought   
suggests and arranges a world of        
particulars4 ,the power of reflection is
 not feebler than the faculty of sense1 
but of a higher and more comprehensive  
nature4 ,it not only receives the       
universals of sense1 but gives them a   
new content by comparing and combining  
them with one another4 ,it withdraws    
from the seen that it may dwell in the  
unseen4 ,the sense only presents us with
 a flat and impenetrable surface3 the   

mind takes the world to pieces and puts 
it together on a new pattern4 ,the      
universals which are detached from sense
 are reconstructed in science4 ,they and
 not the mere impressions of sense are  
the truth of the world in which we live2
 and 7as an argument to those who will  
only believe 'what they can hold in     
their hands'7 we may further observe    
that they are the source of our power   
over it4 ,to say that the outward sense 
is stronger than the inward is like     
saying that the arm of the workman is   
stronger than the constructing or       
directing mind4  ,returning to the      
senses we may briefly consider two      
questions--first their relation to the  
mind1 secondly1 their relation to       
outward objects3--  #a4 ,the senses are 
not merely 'holes set in a wooden horse'
 7,theaet471 but instruments of the mind
 with which they are organically        
connected4 ,there is no use of them     
without some use of words--some natural 
or latent logic--some previous          

experience or observation4 ,sensation1  
like all other mental processes1 is     
complex and relative1 though apparently 
simple4 ,the senses mutually confirm and
 support one another2 it is hard to say 
how much our impressions of hearing may 
be affected by those of sight1 or how   
far our impressions of sight may be     
corrected by the touch1 especially in   
infancy4 ,the confirmation of them by   
one another cannot of course be given by
 any one of them4 ,many intuitions which
 are inseparable from the act of sense  
are really the result of complicated    
reasonings4 ,the most cursory glance at 
objects enables the experienced eye to  
judge approximately of their relations  
and distance1 although nothing is       
impressed upon the retina except colour1
 including gradations of light and      
shade4 ,from these delicate and almost  
imperceptible differences we seem       
chiefly to derive our ideas of distance 
and position4 ,by comparison of what is 
near with what is distant we learn that 

the tree1 house1 river1 etc4 which are a
 long way off are objects of a like     
nature with those which are seen by us  
in our immediate neighbourhood1 although
 the actual impression made on the eye  
is very different in one case and in the
 other4 ,this is a language of 'large   
and small letters' 7,republic71 slightly
 differing in form and exquisitely      
graduated by distance1 which we are     
learning all our life long1 and which we
 attain in various degrees according to 
our powers of sight or observation4     
,there is nor the consideration4 ,the   
greater or less strain upon the nerves  
of the eye or ear is communicated to the
 mind and silently informs the judgment4
 ,we have also the use not of one eye   
only1 but of two1 which give us a wider 
range1 and help us to discern1 by the   
greater or less acuteness of the angle  
which the rays of sight form1 the       
distance of an object and its relation  
to other objects4 ,but we are already   
passing beyond the limits of our actual 

knowledge on a subject which has given  
rise to many conjectures4 ,more         
important than the addition of another  
conjecture is the observation1 whether  
in the case of sight or of any other    
sense1 of the great complexity of the   
causes and the great simplicity of the  
effect4  ,the sympathy of the mind and  
the ear is no less striking than the    
sympathy of the mind and the eye4 ,do we
 not seem to perceive instinctively and 
as an act of sense the differences of   
articulate speech and of musical notes8 
,yet how small a part of speech or of   
music is produced by the impression of  
the ear compared with that which is     
furnished by the mind6  ,again3 the more
 refined faculty of sense1 as in animals
 so also in man1 seems often to be      
transmitted by inheritance4 ,neither    
must we forget that in the use of the   
senses1 as in his whole nature1 man is a
 social being1 who is always being      
educated by language1 habit1 and the    
teaching of other men as well as by his 

own observation4 ,he knows distance     
because he is taught it by a more       
experienced judgment than his own2 he   
distinguishes sounds because he is told 
to remark them by a person of a more    
discerning ear4 ,and as we inherit from 
our parents or other ancestors peculiar 
powers of sense or feeling1 so we       
improve and strengthen them1 not only by
 regular teaching1 but also by sympathy 
and communion with other persons4  #b4  
,the second question1 namely1 that      
concerning the relation of the mind to  
external objects1 is really a trifling  
one1 though it has been made the subject
 of a famous philosophy4 ,we may if we  
like1 with ,berkeley1 resolve objects of
 sense into sensations2 but the change  
is one of name only1 and nothing is     
gained and something is lost by such a  
resolution or confusion of them4 ,for we
 have not really made a single step     
towards idealism1 and any arbitrary     
inversion of our ordinary modes of      
speech is disturbing to the mind4 ,the  

youthful metaphysician is delighted at  
his marvellous discovery that nothing   
is1 and that what we see or feel is our 
sensation only3 for a day or two the    
world has a new interest to him2 he     
alone knows the secret which has been   
communicated to him by the philosopher1 
that mind is all--when in fact he is    
going out of his mind in the first      
intoxication of a great thought4 ,but he
 soon finds that all things remain as   
they were--the laws of motion1 the      
properties of matter1 the qualities of  
substances4 ,after having inflicted his 
theories on any one who is willing to   
receive them 'first on his father and   
mother1 secondly on some other patient  
listener1 thirdly on his dog1' he finds 
that he only differs from the rest of   
mankind in the use of a word4 ,he had   
once hoped that by getting rid of the   
solidity of matter he might open a      
passage to worlds beyond4 ,he liked to  
think of the world as the representation
 of the divine nature1 and delighted to 

imagine angels and spirits wandering    
through space1 present in the room in   
which he is sitting without coming      
through the door1 nowhere and everywhere
 at the same instant4 ,at length he     
finds that he has been the victim of his
 own fancies2 he has neither more nor   
less evidence of the supernatural than  
he had before4 ,he himself has become   
unsettled1 but the laws of the world    
remain fixed as at the beginning4 ,he   
has discovered that his appeal to the   
fallibility of sense was really an      
illusion4 ,for whatever uncertainty     
there may be in the appearances of      
nature1 arises only out of the          
imperfection or variation of the human  
senses1 or possibly from the deficiency 
of certain branches of knowledge2 when  
science is able to apply her tests1 the 
uncertainty is at an end4 ,we are apt   
sometimes to think that moral and       
metaphysical philosophy are lowered by  
the influence which is exercised over   
them by physical science4 ,but any      

interpretation of nature by physical    
science is far in advance of such       
idealism4 ,the philosophy of ,berkeley1 
while giving unbounded license to the   
imagination1 is still grovelling on the 
level of sense4  ,we may1 if we please1 
carry this scepticism a step further1   
and deny1 not only objects of sense1 but
 the continuity of our sensations       
themselves4 ,we may say with ,protagoras
 and ,hume that what is appears1 and    
that what appears appears only to       
individuals1 and to the same individual 
only at one instant4 ,but then1 as      
,plato asks1--and we must repeat the    
question1--,what becomes of the mind8   
,experience tells us by a thousand      
proofs that our sensations of colour1   
taste1 and the like1 are the same as    
they were an instant ago--that the act  
which we are performing one minute is   
continued by us in the next--and also   
supplies abundant proof that the        
perceptions of other men are1 speaking  
generally1 the same or nearly the same  

with our own4 ,after having slowly and  
laboriously in the course of ages gained
 a conception of a whole and parts1 of  
the constitution of the mind1 of the    
relation of man to ,god and nature1     
imperfect indeed1 but the best we can1  
we are asked to return again to the     
'beggarly elements' of ancient          
scepticism1 and acknowledge only atoms  
and sensations devoid of life or unity4 
,why should we not go a step further    
still and doubt the existence of the    
senses of all things8 ,we are but 'such 
stuff as dreams are made of2' for we    
have left ourselves no instruments of   
thought by which we can distinguish man 
from the animals1 or conceive of the    
existence even of a mollusc4 ,and       
observe1 this extreme scepticism has    
been allowed to spring up among us1 not1
 like the ancient scepticism1 in an age 
when nature and language really seemed  
to be full of illusions1 but in the     
eighteenth and nineteenth centuries1    
when men walk in the daylight of        

inductive science4  ,the attractiveness 
of such speculations arises out of their
 true nature not being perceived4 ,they 
are veiled in graceful language2 they   
are not pushed to extremes2 they stop   
where the human mind is disposed also to
 stop--short of a manifest absurdity4   
,their inconsistency is not observed by 
their authors or by mankind in general1 
who are equally inconsistent themselves4
 ,they leave on the mind a pleasing     
sense of wonder and novelty3 in youth   
they seem to have a natural affinity to 
one class of persons as poetry has to   
another2 but in later life either we    
drift back into common sense1 or we make
 them the starting-points of a higher   
philosophy4  ,we are often told that we 
should enquire into all things before we
 accept them2--with what limitations is 
this true8 ,for we cannot use our senses
 without admitting that we have them1 or
 think without presupposing that there  
is in us a power of thought1 or affirm  
that all knowledge is derived from      

experience without implying that this   
first principle of knowledge is prior to
 experience4 ,the truth seems to be that
 we begin with the natural use of the   
mind as of the body1 and we seek to     
describe this as well as we can4 ,we eat
 before we know the nature of digestion2
 we think before we know the nature of  
reflection4 ,as our knowledge increases1
 our perception of the mind enlarges    
also4 ,we cannot indeed get beyond      
facts1 but neither can we draw any line 
which separates facts from ideas4 ,and  
the mind is not something separate from 
them but included in them1 and they in  
the mind1 both having a distinctness and
 individuality of their own4 ,to reduce 
our conception of mind to a succession  
of feelings and sensations is like the  
attempt to view a wide prospect by      
inches through a microscope1 or to      
calculate a period of chronology by     
minutes4 ,the mind ceases to exist when 
it loses its continuity1 which though   
far from being its highest              

determination1 is yet necessary to any  
conception of it4 ,even an inanimate    
nature cannot be adequately represented 
as an endless succession of states or   
conditions4  ,paragraph ,,ii4 ,another  
division of the subject has yet to be   
considered3 ,why should the doctrine    
that knowledge is sensation1 in ancient 
times1 or of sensationalism or          
materialism in modern times1 be allied  
to the lower rather than to the higher  
view of ethical philosophy8 ,at first   
sight the nature and origin of knowledge
 appear to be wholly disconnected from  
ethics and religion1 nor can we deny    
that the ancient ,stoics were           
materialists1 or that the materialist   
doctrines prevalent in modern times have
 been associated with great virtues1 or 
that both religious and philosophical   
idealism have not unfrequently parted   
company with practice4 ,still upon the  
whole it must be admitted that the      
higher standard of duty has gone hand in
 hand with the higher conception of     

knowledge4 ,it is ,protagoras who is    
seeking to adapt himself to the opinions
 of the world2 it is ,plato who rises   
above them3 the one maintaining that all
 knowledge is sensation2 the other      
basing the virtues on the idea of good4 
,the reason of this phenomenon has now  
to be examined4  ,by those who rest     
knowledge immediately upon sense1 that  
explanation of human action is deemed to
 be the truest which is nearest to      
sense4 ,as knowledge is reduced to      
sensation1 so virtue is reduced to      
feeling1 happiness or good to pleasure4 
,the different virtues--the various     
characters which exist in the world--are
 the disguises of self-interest4 ,human 
nature is dried up2 there is no place   
left for imagination1 or in any higher  
sense for religion4 ,ideals of a whole1 
or of a state1 or of a law of duty1 or  
of a divine perfection1 are out of place
 in an ,epicurean philosophy4 ,the very 
terms in which they are expressed are   
suspected of having no meaning4 ,man is 

to bring himself back as far as he is   
able to the condition of a rational     
beast4 ,he is to limit himself to the   
pursuit of pleasure1 but of this he is  
to make a far-sighted calculation2--he  
is to be rationalized1 secularized1     
animalized3 or he is to be an amiable   
sceptic1 better than his own philosophy1
 and not falling below the opinions of  
the world4  ,imagination has been called
 that 'busy faculty' which is always    
intruding upon us in the search after   
truth4 ,but imagination is also that    
higher power by which we rise above     
ourselves and the commonplaces of       
thought and life4 ,the philosophical    
imagination is another name for reason  
finding an expression of herself in the 
outward world4 ,to deprive life of      
ideals is to deprive it of all higher   
and comprehensive aims and of the power 
of imparting and communicating them to  
others4 ,for men are taught1 not by     
those who are on a level with them1 but 
by those who rise above them1 who see   

the distant hills1 who soar into the    
empyrean4 ,like a bird in a cage1 the   
mind confined to sense is always being  
brought back from the higher to the     
lower1 from the wider to the narrower   
view of human knowledge4 ,it seeks to   
fly but cannot3 instead of aspiring     
towards perfection1 'it hovers about    
this lower world and the earthly        
nature4' ,it loses the religious sense  
which more than any other seems to take 
a man out of himself4 ,weary of asking  
',what is truth8' it accepts the 'blind 
witness of eyes and ears2' it draws     
around itself the curtain of the        
physical world and is satisfied4 ,the   
strength of a sensational philosophy    
lies in the ready accommodation of it to
 the minds of men2 many who have been   
metaphysicians in their youth1 as they  
advance in years are prone to acquiesce 
in things as they are1 or rather appear 
to be4 ,they are spectators1 not        
thinkers1 and the best philosophy is    
that which requires of them the least   

amount of mental effort4  ,as a lower   
philosophy is easier to apprehend than a
 higher1 so a lower way of life is      
easier to follow2 and therefore such a  
philosophy seems to derive a support    
from the general practice of mankind4   
,it appeals to principles which they all
 know and recognize3 it gives back to   
them in a generalized form the results  
of their own experience4 ,to the man of 
the world they are the quintessence of  
his own reflections upon life4 ,to      
follow custom1 to have no new ideas or  
opinions1 not to be straining after     
impossibilities1 to enjoy to-day with   
just so much forethought as is necessary
 to provide for the morrow1 this is     
regarded by the greater part of the     
world as the natural way of passing     
through existence4 ,and many who have   
lived thus have attained to a lower kind
 of happiness or equanimity4 ,they have 
possessed their souls in peace without  
ever allowing them to wander into the   
region of religious or political        

controversy1 and without any care for   
the higher interests of man4 ,but nearly
 all the good 7as well as some of the   
evil7 which has ever been done in this  
world has been the work of another      
spirit1 the work of enthusiasts and     
idealists1 of apostles and martyrs4 ,the
 leaders of mankind have not been of the
 gentle ,epicurean type2 they have      
personified ideas2 they have sometimes  
also been the victims of them4 ,but they
 have always been seeking after a truth 
or ideal of which they fell short2 and  
have died in a manner disappointed of   
their hopes that they might lift the    
human race out of the slough in which   
they found them4 ,they have done little 
compared with their own visions and     
aspirations2 but they have done that    
little1 only because they sought to do1 
and once perhaps thought that they were 
doing1 a great deal more4  ,the         
philosophies of ,epicurus or ,hume give 
no adequate or dignified conception of  
the mind4 ,there is no organic unity in 

a succession of feeling or sensations2  
no comprehensiveness in an infinity of  
separate actions4 ,the individual never 
reflects upon himself as a whole2 he can
 hardly regard one act or part of his   
life as the cause or effect of any other
 act or part4 ,whether in practice or   
speculation1 he is to himself only in   
successive instants4 ,to such thinkers1 
whether in ancient or in modern times1  
the mind is only the poor recipient of  
impressions--not the heir of all the    
ages1 or connected with all other minds4
 ,it begins again with its own modicum  
of experience having only such vague    
conceptions of the wisdom of the past as
 are inseparable from language and      
popular opinion4 ,it seeks to explain   
from the experience of the individual   
what can only be learned from the       
history of the world4 ,it has no        
conception of obligation1 duty1         
conscience--these are to the ,epicurean 
or ,utilitarian philosopher only names  
which interfere with our natural        

perceptions of pleasure and pain4       
,there seem then to be several answers  
to the question1 ,why the theory that   
all knowledge is sensation is allied to 
the lower rather than to the higher view
 of ethical philosophy3--#ast1 ,because 
it is easier to understand and practise2
 #bndly1 ,because it is fatal to the    
pursuit of ideals1 moral1 political1 or 
religious2 #crdly1 ,because it deprives 
us of the means and instruments of      
higher thought1 of any adequate         
conception of the mind1 of knowledge1 of
 conscience1 of moral obligation4  444  
,,on ,,the ,,nature ,,and ,,limits ,of  
,,psychology4       ,o gar arche men o  
me oide1 teleute de kai ta metaxu ex ou 
me      oide sumpeplektai1 tis mechane  
ten toiauten omologian pote             
epistemen genesthai2 ,plato ,republic4  
,monon gar auto legeiv1 osper gumnon kai
 aperemomenon apo ton      onton        
apanton1 adunaton4  ,soph4  ,since the  
above essay first appeared1 many books  
on ,psychology have been given to the   

world1 partly based upon the views of   
,herbart and other ,german philosophers1
 partly independent of them4 ,the       
subject has gained in bulk and extent2  
whether it has had any true growth is   
more doubtful4 ,it begins to assume the 
language and claim the authority of a   
science2 but it is only an hypothesis or
 outline1 which may be filled up in many
 ways according to the fancy of         
individual thinkers4 ,the basis of it is
 a precarious one1--consciousness of    
ourselves and a somewhat uncertain      
observation of the rest of mankind4 ,its
 relations to other sciences are not yet
 determined3 they seem to be almost too 
complicated to be ascertained4 ,it may  
be compared to an irregular building1   
run up hastily and not likely to last1  
because its foundations are weak1 and in
 many places rest only on the surface of
 the ground4 ,it has sought rather to   
put together scattered observations and 
to make them into a system than to      
describe or prove them4 ,it has never   

severely drawn the line between facts   
and opinions4 ,it has substituted a     
technical phraseology for the common use
 of language1 being neither able to win 
acceptance for the one nor to get rid of
 the other4  ,the system which has thus 
arisen appears to be a kind of          
metaphysic narrowed to the point of view
 of the individual mind1 through which1 
as through some new optical instrument  
limiting the sphere of vision1 the      
interior of thought and sensation is    
examined4 ,but the individual mind in   
the abstract1 as distinct from the mind 
of a particular individual and separated
 from the environment of circumstances1 
is a fiction only4 ,yet facts which are 
partly true gather around this fiction  
and are naturally described by the help 
of it4 ,there is also a common type of  
the mind which is derived from the      
comparison of many minds with one       
another and with our own4 ,the phenomena
 of which ,psychology treats are        
familiar to us1 but they are for the    

most part indefinite2 they relate to a  
something inside the body1 which seems  
also to overleap the limits of space4   
,the operations of this something1 when 
isolated1 cannot be analyzed by us or   
subjected to observation and experiment4
 ,and there is another point to be      
considered4 ,the mind1 when thinking1   
cannot survey that part of itself which 
is used in thought4 ,it can only be     
contemplated in the past1 that is to    
say1 in the history of the individual or
 of the world4 ,this is the scientific  
method of studying the mind4 ,but       
,psychology has also some other         
supports1 specious rather than real4 ,it
 is partly sustained by the false       
analogy of ,physical ,science and has   
great expectations from its near        
relationship to ,physiology4 ,we truly  
remark that there is an infinite        
complexity of the body corresponding to 
the infinite subtlety of the mind2 we   
are conscious that they are very nearly 
connected4 ,but in endeavouring to trace

 the nature of the connexion we are     
baffled and disappointed4 ,in our       
knowledge of them the gulf remains the  
same3 no microscope has ever seen into  
thought2 no reflection on ourselves has 
supplied the missing link between mind  
and matter444,these are the conditions  
of this very inexact science1 and we    
shall only know less of it by pretending
 to know more1 or by assigning to it a  
form or style to which it has not yet   
attained and is not really entitled4    
,experience shows that any system1      
however baseless and ineffectual1 in our
 own or in any other age1 may be        
accepted and continue to be studied1 if 
it seeks to satisfy some unanswered     
question or is based upon some ancient  
tradition1 especially if it takes the   
form and uses the language of inductive 
philosophy4 ,the fact therefore that    
such a science exists and is popular1   
affords no evidence of its truth or     
value4 ,many who have pursued it far    
into detail have never examined the     

foundations on which it rests4 ,the have
 been many imaginary subjects of        
knowledge of which enthusiastic persons 
have made a lifelong study1 without ever
 asking themselves what is the evidence 
for them1 what is the use of them1 how  
long they will last8 ,they may pass     
away1 like the authors of them1 and     
'leave not a wrack behind2' or they may 
survive in fragments4 ,nor is it only in
 the ,middle ,ages1 or in the literary  
desert of ,china or of ,india1 that such
 systems have arisen2 in our own        
enlightened age1 growing up by the side 
of ,physics1 ,ethics1 and other really  
progressive sciences1 there is a weary  
waste of knowledge1 falsely so-called4  
,there are sham sciences which no logic 
has ever put to the test1 in which the  
desire for knowledge invents the        
materials of it4  ,and therefore it is  
expedient once more to review the bases 
of ,psychology1 lest we should be       
imposed upon by its pretensions4 ,the   
study of it may have done good service  

by awakening us to the sense of         
inveterate errors familiarized by       
language1 yet it may have fallen into   
still greater ones2 under the pretence  
of new investigations it may be wasting 
the lives of those who are engaged in   
it4 ,it may also be found that the      
discussion of it will throw light upon  
some points in the ,theaetetus of       
,plato1--the oldest work on ,psychology 
which has come down to us4 ,the         
imaginary science may be called1 in the 
language of ancient philosophy1 'a      
shadow of a part of ,dialectic or       
,metaphysic' 7,gorg474  ,in this        
postscript or appendix we propose to    
treat1 first1 of the true bases of      
,psychology2 secondly1 of the errors    
into which the students of it are most  
likely to fall2 thirdly1 of the         
principal subjects which are usually    
comprehended under it2 fourthly1 of the 
form which facts relating to the mind   
most naturally assume4  ,we may preface 
the enquiry by two or three remarks3--  

7#a7 ,we do not claim for the popular   
,psychology the position of a science at
 all2 it cannot1 like the ,physical     
,sciences1 proceed by the ,inductive    
,method3 it has not the necessity of    
,mathematics3 it does not1 like         
,metaphysic1 argue from abstract notions
 or from internal coherence4 ,it is made
 up of scattered observations4 ,a few of
 these1 though they may sometimes appear
 to be truisms1 are of the greatest     
value1 and free from all doubt4 ,we are 
conscious of them in ourselves2 we      
observe them working in others2 we are  
assured of them at all times4 ,for      
example1 we are absolutely certain1 7a7 
of the influence exerted by the mind    
over the body or by the body over the   
mind3 7b7 of the power of association1  
by which the appearance of some person  
or the occurrence of some event recalls 
to mind1 not always but often1 other    
persons and events3 7c7 of the effect of
 habit1 which is strongest when least   
disturbed by reflection1 and is to the  

mind what the bones are to the body3 7d7
 of the real1 though not unlimited1     
freedom of the human will3 7e7 of the   
reference1 more or less distinct1 of our
 sensations1 feelings1 thoughts1        
actions1 to ourselves1 which is called  
consciousness1 or1 when in excess1      
self-consciousness3 7f7 of the          
distinction of the ',i' and ',not ,i1'  
of ourselves and outward objects4 ,but  
when we attempt to gather up these      
elements in a single system1 we discover
 that the links by which we combine them
 are apt to be mere words4 ,we are in a 
country which has never been cleared or 
surveyed2 here and there only does a    
gleam of light come through the darkness
 of the forest4  7#b7 ,these fragments1 
although they can never become science  
in the ordinary sense of the word1 are a
 real part of knowledge and may be of   
great value in education4 ,we may be    
able to add a good deal to them from our
 own experience1 and we may verify them 
by it4 ,self-examination is one of those

 studies which a man can pursue alone1  
by attention to himself and the         
processes of his individual mind4 ,he   
may learn much about his own character  
and about the character of others1 if he
 will 'make his mind sit down' and look 
at itself in the glass4 ,the great1 if  
not the only use of such a study is a   
practical one1--to know1 first1 human   
nature1 and1 secondly1 our own nature1  
as it truly is4  7#c7 ,hence it is      
important that we should conceive of the
 mind in the noblest and simplest       
manner4 ,while acknowledging that       
language has been the greatest factor in
 the formation of human thought1 we must
 endeavour to get rid of the disguises1 
oppositions1 contradictions1 which arise
 out of it4 ,we must disengage ourselves
 from the ideas which the customary use 
of words has implanted in us4 ,to avoid 
error as much as possible when we are   
speaking of things unseen1 the principal
 terms which we use should be few1 and  
we should not allow ourselves to be     

enslaved by them4 ,instead of seeking to
 frame a technical language1 we should  
vary our forms of speech1 lest they     
should degenerate into formulas4 ,a     
difficult philosophical problem is      
better understood when translated into  
the vernacular4  ,i4a4 ,psychology is   
inseparable from language1 and early    
language contains the first impressions 
or the oldest experience of man         
respecting himself4 ,these impressions  
are not accurate representations of the 
truth2 they are the reflections of a    
rudimentary age of philosophy4 ,the     
first and simplest forms of thought are 
rooted so deep in human nature that they
 can never be got rid of2 but they have 
been perpetually enlarged and elevated1 
and the use of many words has been      
transferred from the body to the mind4  
,the spiritual and intellectual have    
thus become separated from the          
material--there is a cleft between them2
 and the heart and the conscience of man
 rise above the dominion of the         

appetites and create a new language in  
which they too find expression4 ,as the 
differences of actions begin to be      
perceived1 more and more names are      
needed4 ,this is the first analysis of  
the human mind2 having a general        
foundation in popular experience1 it is 
moulded to a certain extent by          
hierophants and philosophers4 7,see     
,introd4 to ,cratylus47  b4 ,this       
primitive psychology is continually     
receiving additions from the first      
thinkers1 who in return take a colour   
from the popular language of the time4  
,the mind is regarded from new points of
 view1 and becomes adapted to new       
conditions of knowledge4 ,it seeks to   
isolate itself from matter and sense1   
and to assert its independence in       
thought4 ,it recognizes that it is      
independent of the external world4 ,it  
has five or six natural states or       
stages3--7#a7 sensation1 in which it is 
almost latent or quiescent3 7#b7        
feeling1 or inner sense1 when the mind  

is just awakening3 7#c7 memory1 which is
 decaying sense1 and from time to time1 
as with a spark or flash1 has the power 
of recollecting or reanimating the      
buried past3 7#d7 thought1 in which     
images pass into abstract notions or are
 intermingled with them3 7#e7 action1 in
 which the mind moves forward1 of       
itself1 or under the impulse of want or 
desire or pain1 to attain or avoid some 
end or consequence3 and 7#f7 there is   
the composition of these or the         
admixture or assimilation of them in    
various degrees4 ,we never see these    
processes of the mind1 nor can we tell  
the causes of them4 ,but we know them by
 their results1 and learn from other men
 that so far as we can describe to them 
or they to us the workings of the mind1 
their experience is the same or nearly  
the same with our own4  c4 ,but the     
knowledge of the mind is not to any     
great extent derived from the           
observation of the individual by        
himself4 ,it is the growing             

consciousness of the human race1        
embodied in language1 acknowledged by   
experience1 and corrected from time to  
time by the influence of literature and 
philosophy4 ,a great1 perhaps the most  
important1 part of it is to be found in 
early ,greek thought4 ,in the           
,theaetetus of ,plato it has not yet    
become fixed3 we are still stumbling on 
the threshold4 ,in ,aristotle the       
process is more nearly completed1 and   
has gained innumerable abstractions1 of 
which many have had to be thrown away   
because relative only to the            
controversies of the time4 ,in the      
interval between ,thales and ,aristotle 
were realized the distinctions of mind  
and body1 of universal and particular1  
of infinite and infinitesimal1 of idea  
and phenomenon2 the class conceptions of
 faculties and virtues1 the antagonism  
of the appetites and the reason2 and    
connected with this1 at a higher stage  
of development1 the opposition of moral 
and intellectual virtue2 also the       

primitive conceptions of unity1 being1  
rest1 motion1 and the like4 ,these      
divisions were not really scientific1   
but rather based on popular experience4 
,they were not held with the precision  
of modern thinkers1 but taken all       
together they gave a new existence to   
the mind in thought1 and greatly        
enlarged and more accurately defined    
man's knowledge of himself and of the   
world4 ,the majority of them have been  
accepted by ,christian and ,western     
nations4 ,yet in modern times we have   
also drifted so far away from           
,aristotle1 that if we were to frame a  
system on his lines we should be at war 
with ordinary language and untrue to our
 own consciousness4 ,and there have been
 a few both in mediaeval times and since
 the ,reformation who have rebelled     
against the ,aristotelian point of view4
 ,of these eccentric thinkers there have
 been various types1 but they have all a
 family likeness4 ,according to them1   
there has been too much analysis and too

 little synthesis1 too much division of 
the mind into parts and too little      
conception of it as a whole or in its   
relation to ,god and the laws of the    
universe4 ,they have thought that the   
elements of plurality and unity have not
 been duly adjusted4 ,the tendency of   
such writers has been to allow the      
personality of man to be absorbed in the
 universal1 or in the divine nature1 and
 to deny the distinction between matter 
and mind1 or to substitute one for the  
other4 ,they have broken some of the    
idols of ,psychology3 they have         
challenged the received meaning of      
words3 they have regarded the mind under
 many points of view4 ,but though they  
may have shaken the old1 they have not  
established the new2 their views of     
philosophy1 which seem like the echo of 
some voice from the ,east1 have been    
alien to the mind of ,europe4  d4 ,the  
,psychology which is found in common    
language is in some degree verified by  
experience1 but not in such a manner as 

to give it the character of an exact    
science4 ,we cannot say that words      
always correspond to facts4 ,common     
language represents the mind from       
different and even opposite points of   
view1 which cannot be all of them       
equally true 7compare ,cratylus74 ,yet  
from diversity of statements and        
opinions may be obtained a nearer       
approach to the truth than is to be     
gained from any one of them4 ,it also   
tends to correct itself1 because it is  
gradually brought nearer to the common  
sense of mankind4 ,there are some       
leading categories or classifications of
 thought1 which1 though unverified1 must
 always remain the elements from which  
the science or study of the mind        
proceeds4 ,for example1 we must assume  
ideas before we can analyze them1 and   
also a continuing mind to which they    
belong2 the resolution of it into       
successive moments1 which would say1    
with ,protagoras1 that the man is not   
the same person which he was a minute   

ago1 is1 as ,plato implies in the       
,theaetetus1 an absurdity4  e4 ,the     
growth of the mind1 which may be traced 
in the histories of religions and       
philosophies and in the thoughts of     
nations1 is one of the deepest and      
noblest modes of studying it4 ,here we  
are dealing with the reality1 with the  
greater and1 as it may be termed1 the   
most sacred part of history4 ,we study  
the mind of man as it begins to be      
inspired by a human or divine reason1 as
 it is modified by circumstances1 as it 
is distributed in nations1 as it is     
renovated by great movements1 which go  
beyond the limits of nations and affect 
human society on a scale still greater1 
as it is created or renewed by great    
minds1 who1 looking down from above1    
have a wider and more comprehensive     
vision4 ,this is an ambitious study1 of 
which most of us rather 'entertain      
conjecture' than arrive at any detailed 
or accurate knowledge4 ,later arises the
 reflection how these great ideas or    

movements of the world have been        
appropriated by the multitude and found 
a way to the minds of individuals4 ,the 
real ,psychology is that which shows how
 the increasing knowledge of nature and 
the increasing experience of life have  
always been slowly transforming the     
mind1 how religions too have been       
modified in the course of ages 'that    
,god may be all and in all4' ,e         
pollaplasion1 eoe1 to ergon e os nun    
zeteitai prostatteis4  f4 ,lastly1      
though we speak of the study of mind in 
a special sense1 it may also be said    
that there is no science which does not 
contribute to our knowledge of it4 ,the 
methods of science and their analogies  
are new faculties1 discovered by the few
 and imparted to the many4 ,they are to 
the mind1 what the senses are to the    
body2 or better1 they may be compared to
 instruments such as the telescope or   
microscope by which the discriminating  
power of the senses1 or to other        
mechanical inventions1 by which the     

strength and skill of the human body is 
so immeasurably increased4  ,,ii4 ,the  
new ,psychology1 whatever may be its    
claim to the authority of a science1 has
 called attention to many facts and     
corrected many errors1 which without it 
would have been unexamined4 ,yet it is  
also itself very liable to illusion4    
,the evidence on which it rests is vague
 and indefinite4 ,the field of          
consciousness is never seen by us as a  
whole1 but only at particular points1   
which are always changing4 ,the veil of 
language intercepts facts4 ,hence it is 
desirable that in making an approach to 
the study we should consider at the     
outset what are the kinds of error which
 most easily affect it1 and note the    
differences which separate it from other
 branches of knowledge4  a4 ,first1 we  
observe the mind by the mind4 ,it would 
seem therefore that we are always in    
danger of leaving out the half of that  
which is the subject of our enquiry4 ,we
 come at once upon the difficulty of    

what is the meaning of the word4 ,does  
it differ as subject and object in the  
same manner8 ,can we suppose one set of 
feelings or one part of the mind to     
interpret another8 ,is the introspecting
 thought the same with the thought which
 is introspected8 ,has the mind the     
power of surveying its whole domain at  
one and the same time8--,no more than   
the eye can take in the whole human body
 at a glance4 ,yet there may be a       
glimpse round the corner1 or a thought  
transferred in a moment from one point  
of view to another1 which enables us to 
see nearly the whole1 if not at once1 at
 any rate in succession4 ,such glimpses 
will hardly enable us to contemplate    
from within the mind in its true        
proportions4 ,hence the firmer ground of
 ,psychology is not the consciousness of
 inward feelings but the observation of 
external actions1 being the actions not 
only of ourselves1 but of the           
innumerable persons whom we come across 
in life4  b4 ,the error of supposing    

partial or occasional explanation of    
mental phenomena to be the only or      
complete ones4 ,for example1 we are     
disinclined to admit of the spontaneity 
or discontinuity of the mind--it seems  
to us like an effect without a cause1   
and therefore we suppose the train of   
our thoughts to be always called up by  
association4 ,yet it is probable1 or    
indeed certain1 that of many mental     
phenomena there are no mental           
antecedents1 but only bodily ones4  c4  
,the false influence of language4 ,we   
are apt to suppose that when there are  
two or more words describing faculties  
or processes of the mind1 there are real
 differences corresponding to them4 ,but
 this is not the case4 ,nor can we      
determine how far they do or do not     
exist1 or by what degree or kind of     
difference they are distinguished4 ,the 
same remark may be made about figures of
 speech4 ,they fill up the vacancy of   
knowledge2 they are to the mind what too
 much colour is to the eye2 but the     

truth is rather concealed than revealed 
by them4  d4 ,the uncertain meaning of  
terms1 such as ,consciousness1          
,conscience1 ,will1 ,law1 ,knowledge1   
,internal and ,external ,sense2 these1  
in the language of ,plato1 'we          
shamelessly use1 without ever having    
taken the pains to analyze them4'  e4 ,a
 science such as ,psychology is not     
merely an hypothesis1 but an hypothesis 
which1 unlike the hypotheses of         
,physics1 can never be verified4 ,it    
rests only on the general impressions of
 mankind1 and there is little or no hope
 of adding in any considerable degree to
 our stock of mental facts4  f4 ,the    
parallelism of the ,physical ,sciences1 
which leads us to analyze the mind on   
the analogy of the body1 and so to      
reduce mental operations to the level of
 bodily ones1 or to confound one with   
the other4  g4 ,that the progress of    
,physiology may throw a new light on    
,psychology is a dream in which         
scientific men are always tempted to    

indulge4 ,but however certain we may be 
of the connexion between mind and body1 
the explanation of the one by the other 
is a hidden place of nature which has   
hitherto been investigated with little  
or no success4  h4 ,the impossibility of
 distinguishing between mind and body4  
,neither in thought nor in experience   
can we separate them4 ,they seem to act 
together2 yet we feel that we are       
sometimes under the dominion of the one1
 sometimes of the other1 and sometimes1 
both in the common use of language and  
in fact1 they transform themselves1 the 
one into the good principle1 the other  
into the evil principle2 and then again 
the ',i' comes in and mediates between  
them4 ,it is also difficult to          
distinguish outward facts from the ideas
 of them in the mind1 or to separate the
 external stimulus to a sensation from  
the activity of the organ1 or this from 
the invisible agencies by which it      
reaches the mind1 or any process of     
sense from its mental antecedent1 or any

 mental energy from its nervous         
expression4  i4 ,the fact that mental   
divisions tend to run into one another1 
and that in speaking of the mind we     
cannot always distinguish differences of
 kind from differences of degree2 nor   
have we any measure of the strength and 
intensity of our ideas or feelings4  j4 
,although heredity has been always known
 to the ancients as well as ourselves to
 exercise a considerable influence on   
human character1 yet we are unable to   
calculate what proportion this          
birth-influence bears to nurture and    
education4 ,but this is the real        
question4 ,we cannot pursue the mind    
into embryology3 we can only trace how1 
after birth1 it begins to grow4 ,but how
 much is due to the soil1 how much to   
the original latent seed1 it is         
impossible to distinguish4 ,and because 
we are certain that heredity exercises a
 considerable1 but undefined influence1 
we must not increase the wonder by      
exaggerating it4  k4 ,the love of system

 is always tending to prevail over the  
historical investigation of the mind1   
which is our chief means of knowing it4 
,it equally tends to hinder the other   
great source of our knowledge of the    
mind1 the observation of its workings   
and processes which we can make for     
ourselves4  l4 ,the mind1 when studied  
through the individual1 is apt to be    
isolated--this is due to the very form  
of the enquiry2 whereas1 in truth1 it is
 indistinguishable from circumstances1  
the very language which it uses being   
the result of the instincts of          
long-forgotten generations1 and every   
word which a man utters being the answer
 to some other word spoken or suggested 
by somebody else4  ,,iii4 ,the tendency 
of the preceding remarks has been to    
show that ,psychology is necessarily a  
fragment1 and is not and cannot be a    
connected system4 ,we cannot define or  
limit the mind1 but we can describe it4 
,we can collect information about it2 we
 can enumerate the principal subjects   

which are included in the study of it4  
,thus we are able to rehabilitate       
,psychology to some extent1 not as a    
branch of science1 but as a collection  
of facts bearing on human life1 as a    
part of the history of philosophy1 as an
 aspect of ,metaphysic4 ,it is a        
fragment of a science only1 which in all
 probability can never make any great   
progress or attain to much clearness or 
exactness4 ,it is however a kind of     
knowledge which has a great interest for
 us and is always present to us1 and of 
which we carry about the materials in   
our own bosoms4 ,we can observe our     
minds and we can experiment upon them1  
and the knowledge thus acquired is not  
easily forgotten1 and is a help to us in
 study as well as in conduct4  ,the     
principal subjects of ,psychology may be
 summed up as follows3--  a4 ,the       
relation of man to the world around     
him1--in what sense and within what     
limits can he withdraw from its laws or 
assert himself against them 7,freedom   

and ,necessity71 and what is that which 
we suppose to be thus independent and   
which we call ourselves8 ,how does the  
inward differ from the outward and what 
is the relation between them1 and where 
do we draw the line by which we separate
 mind from matter1 the soul from the    
body8 ,is the mind active or passive1 or
 partly both8 ,are its movements        
identical with those of the body1 or    
only preconcerted and coincident with   
them1 or is one simply an aspect of the 
other8  b4 ,what are we to think of time
 and space8 ,time seems to have a nearer
 connexion with the mind1 space with the
 body2 yet time1 as well as space1 is   
necessary to our idea of either4 ,we see
 also that they have an analogy with one
 another1 and that in ,mathematics they 
often interpenetrate4 ,space or place   
has been said by ,kant to be the form of
 the outward1 time of the inward sense4 
,he regards them as parts or forms of   
the mind4 ,but this is an unfortunate   
and inexpressive way of describing their

 relation to us4 ,for of all the        
phenomena present to the human mind they
 seem to have most the character of     
objective existence4 ,there is no use in
 asking what is beyond or behind them2  
we cannot get rid of them4 ,and to throw
 the laws of external nature which to us
 are the type of the immutable into the 
subjective side of the antithesis seems 
to be equally inappropriate4  c4 ,when  
in imagination we enter into the closet 
of the mind and withdraw ourselves from 
the external world1 we seem to find     
there more or less distinct processes   
which may be described by the words1 ',i
 perceive1' ',i feel1' ',i think1' ',i  
want1' ',i wish1' ',i like1' ',i        
dislike1' ',i fear1' ',i know1' ',i     
remember1' ',i imagine1' ',i dream1' ',i
 act1' ',i endeavour1' ',i hope4' ,these
 processes would seem to have the same  
notions attached to them in the minds of
 all educated persons4 ,they are        
distinguished from one another in       
thought1 but they intermingle4 ,it is   

possible to reflect upon them or to     
become conscious of them in a greater or
 less degree1 or with a greater or less 
continuity or attention1 and thus arise 
the intermittent phenomena of           
consciousness or self-consciousness4    
,the use of all of them is possible to  
us at all times2 and therefore in any   
operation of the mind the whole are     
latent4 ,but we are able to characterise
 them sufficiently by that part of the  
complex action which is the most        
prominent4 ,we have no difficulty in    
distinguishing an act of sight or an act
 of will from an act of thought1        
although thought is present in both of  
them4 ,hence the conception of different
 faculties or different virtues is      
precarious1 because each of them is     
passing into the other1 and they are all
 one in the mind itself2 they appear and
 reappear1 and may all be regarded as   
the ever-varying phases or aspects or   
differences of the same mind or person4 
d4 ,nearest the sense in the scale of   

the intellectual faculties is memory1   
which is a mode rather than a faculty of
 the mind1 and accompanies all mental   
operations4 ,there are two principal    
kinds of it1 recollection and           
recognition1--recollection in which     
forgotten things are recalled or return 
to the mind1 recognition in which the   
mind finds itself again among things    
once familiar4 ,the simplest way in     
which we can represent the former to    
ourselves is by shutting our eyes and   
trying to recall in what we term the    
mind's eye the picture of the           
surrounding scene1 or by laying down the
 book which we are reading and          
recapitulating what we can remember of  
it4 ,but many times more powerful than  
recollection is recognition1 perhaps    
because it is more assisted by          
association4 ,we have known and         
forgotten1 and after a long interval the
 thing which we have seen once is seen  
again by us1 but with a different       
feeling1 and comes back to us1 not as   

new knowledge1 but as a thing to which  
we ourselves impart a notion already    
present to us2 in ,plato's words1 we set
 the stamp upon the wax4 ,every one is  
aware of the difference between the     
first and second sight of a place1      
between a scene clothed with            
associations or bare and divested of    
them4 ,we say to ourselves on revisiting
 a spot after a long interval3 ,how many
 things have happened since ,i last saw 
this6 ,there is probably no impression  
ever received by us of which we can     
venture to say that the vestiges are    
altogether lost1 or that we might not1  
under some circumstances1 recover it4 ,a
 long-forgotten knowledge may be easily 
renewed and therefore is very different 
from ignorance4 ,of the language learnt 
in childhood not a word may be          
remembered1 and yet1 when a new         
beginning is made1 the old habit soon   
returns1 the neglected organs come back 
into use1 and the river of speech finds 
out the dried-up channel4  e4           

',consciousness' is the most treacherous
 word which is employed in the study of 
the mind1 for it is used in many senses1
 and has rarely1 if ever1 been minutely 
analyzed4 ,like memory1 it accompanies  
all mental operations1 but not always   
continuously1 and it exists in various  
degrees4 ,it may be imperceptible or    
hardly perceptible3 it may be the living
 sense that our thoughts1 actions1      
sufferings1 are our own4 ,it is a kind  
of attention which we pay to ourselves1 
and is intermittent rather than         
continuous4 ,its sphere has been        
exaggerated4 ,it is sometimes said to   
assure us of our freedom2 but this is an
 illusion3 as there may be a real       
freedom without consciousness of it1 so 
there may be a consciousness of freedom 
without the reality4 ,it may be regarded
 as a higher degree of knowledge when we
 not only know but know that we know4   
,consciousness is opposed to habit1     
inattention1 sleep1 death4 ,it may be   
illustrated by its derivative           

conscience1 which speaks to men1 not    
only of right and wrong in the abstract1
 but of right and wrong actions in      
reference to themselves and their       
circumstances4  f4 ,association is      
another of the ever-present phenomena of
 the human mind4 ,we speak of the laws  
of association1 but this is an          
expression which is confusing1 for the  
phenomenon itself is of the most        
capricious and uncertain sort4 ,it may  
be briefly described as follows4 ,the   
simplest case of association is that of 
sense4 ,when we see or hear separately  
one of two things1 which we have        
previously seen or heard together1 the  
occurrence of the one has a tendency to 
suggest the other4 ,so the sight or name
 of a house may recall to our minds the 
memory of those who once lived there4   
,like may recall like and everything its
 opposite4 ,the parts of a whole1 the   
terms of a series1 objects lying near1  
words having a customary order stick    
together in the mind4 ,a word may bring 

back a passage of poetry or a whole     
system of philosophy2 from one end of   
the world or from one pole of knowledge 
we may travel to the other in an        
indivisible instant4 ,the long train of 
association by which we pass from one   
point to the other1 involving every sort
 of complex relation1 so sudden1 so     
accidental1 is one of the greatest      
wonders of mind444,this process however 
is not always continuous1 but often     
intermittent3 we can think of things in 
isolation as well as in association2 we 
do not mean that they must all hang from
 one another4 ,we can begin again after 
an interval of rest or vacancy1 as a new
 train of thought suddenly arises1 as1  
for example1 when we wake of a morning  
or after violent exercise4 ,time1 place1
 the same colour or sound or smell or   
taste1 will often call up some thought  
or recollection either accidentally or  
naturally associated with them4 ,but it 
is equally noticeable that the new      
thought may occur to us1 we cannot tell 

how or why1 by the spontaneous action of
 the mind itself or by the latent       
influence of the body4 ,both science and
 poetry are made up of associations or  
recollections1 but we must observe also 
that the mind is not wholly dependent on
 them1 having also the power of         
origination4  ,there are other processes
 of the mind which it is good for us to 
study when we are at home and by        
ourselves1--the manner in which thought 
passes into act1 the conflict of passion
 and reason in many stages1 the         
transition from sensuality to love or   
sentiment and from earthly love to      
heavenly1 the slow and silent influence 
of habit1 which little by little changes
 the nature of men1 the sudden change of
 the old nature of man into a new one1  
wrought by shame or by some other       
overwhelming impulse4 ,these are the    
greater phenomena of mind1 and he who   
has thought of them for himself will    
live and move in a better-ordered world1
 and will himself be a better-ordered   

man4  ,at the other end of the 'globus  
intellectualis1' nearest1 not to earth  
and sense1 but to heaven and ,god1 is   
the personality of man1 by which he     
holds communion with the unseen world4  
,somehow1 he knows not how1 somewhere1  
he knows not where1 under this higher   
aspect of his being he grasps the ideas 
of ,god1 freedom and immortality2 he    
sees the forms of truth1 holiness and   
love1 and is satisfied with them4 ,no   
account of the mind can be complete     
which does not admit the reality or the 
possibility of another life4 ,whether   
regarded as an ideal or as a fact1 the  
highest part of man's nature and that in
 which it seems most nearly to approach 
the divine1 is a phenomenon which       
exists1 and must therefore be included  
within the domain of ,psychology4  ,,iv4
 ,we admit that there is no perfect or  
ideal ,psychology4 ,it is not a whole in
 the same sense in which ,chemistry1    
,physiology1 or ,mathematics are wholes3
 that is to say1 it is not a connected  

unity of knowledge4 ,compared with the  
wealth of other sciences1 it rests upon 
a small number of facts2 and when we go 
beyond these1 we fall into conjectures  
and verbal discussions4 ,the facts      
themselves are disjointed2 the causes of
 them run up into other sciences1 and we
 have no means of tracing them from one 
to the other4 ,yet it may be true of    
this1 as of other beginnings of         
knowledge1 that the attempt to put them 
together has tested the truth of them1  
and given a stimulus to the enquiry into
 them4  ,psychology should be natural1  
not technical4 ,it should take the form 
which is the most intelligible to the   
common understanding1 because it has to 
do with common things1 which are        
familiar to us all4 ,it should aim at no
 more than every reflecting man knows or
 can easily verify for himself4 ,when   
simple and unpretentious1 it is least   
obscured by words1 least liable to fall 
under the influence of ,physiology or   
,metaphysic4 ,it should argue1 not from 

exceptional1 but from ordinary          
phenomena4 ,it should be careful to     
distinguish the higher and the lower    
elements of human nature1 and not allow 
one to be veiled in the disguise of the 
other1 lest through the slippery nature 
of language we should pass imperceptibly
 from good to evil1 from nature in the  
higher to nature in the neutral or lower
 sense4 ,it should assert consistently  
the unity of the human faculties1 the   
unity of knowledge1 the unity of ,god   
and law4 ,the difference between the    
will and the affections and between the 
reason and the passions should also be  
recognized by it4  ,its sphere is       
supposed to be narrowed to the          
individual soul2 but it cannot be thus  
separated in fact4 ,it goes back to the 
beginnings of things1 to the first      
growth of language and philosophy1 and  
to the whole science of man4 ,there can 
be no truth or completeness in any study
 of the mind which is confined to the   
individual4 ,the nature of language1    

though not the whole1 is perhaps at     
present the most important element in   
our knowledge of it4 ,it is not         
impossible that some numerical laws may 
be found to have a place in the         
relations of mind and matter1 as in the 
rest of nature4 ,the old ,pythagorean   
fancy that the soul 'is or has in it    
harmony' may in some degree be realized4
 ,but the indications of such numerical 
harmonies are faint2 either the secret  
of them lies deeper than we can         
discover1 or nature may have rebelled   
against the use of them in the          
composition of men and animals4 ,it is  
with qualitative rather than with       
quantitative differences that we are    
concerned in ,psychology4 ,the facts    
relating to the mind which we obtain    
from ,physiology are negative rather    
than positive4 ,they show us1 not the   
processes of mental action1 but the     
conditions of which when deprived the   
mind ceases to act4 ,it would seem as if
 the time had not yet arrived when we   

can hope to add anything of much        
importance to our knowledge of the mind 
from the investigations of the          
microscope4 ,the elements of ,psychology
 can still only be learnt from          
reflections on ourselves1 which         
interpret and are also interpreted by   
our experience of others4 ,the history  
of language1 of philosophy1 and         
religion1 the great thoughts or         
inventions or discoveries which move    
mankind1 furnish the larger moulds or   
outlines in which the human mind has    
been cast4 ,from these the individual   
derives so much as he is able to        
comprehend or has the opportunity of    
learning4     ,,theaetetus   ,,persons  
,,of ,,the ,,dialogue3 ,socrates1       
,theodorus1 ,theaetetus4  ,euclid and   
,terpsion meet in front of ,euclid's    
house in ,megara2 they enter the house1 
and the dialogue is read to them by a   
servant4   ,,euclid3 ,have you only just
 arrived from the country1 ,terpsion8   
,,terpsion3 ,no1 ,i came some time ago3 

and ,i have been in the ,agora looking  
for you1 and wondering that ,i could not
 find you4  ,,euclid3 ,but ,i was not in
 the city4  ,,terpsion3 ,where then8    
,,euclid3 ,as ,i was going down to the  
harbour1 ,i met ,theaetetus--he was     
being carried up to ,athens from the    
army at ,corinth4  ,,terpsion3 ,was he  
alive or dead8  ,,euclid3 ,he was       
scarcely alive1 for he has been badly   
wounded2 but he was suffering even more 
from the sickness which has broken out  
in the army4  ,,terpsion3 ,the          
dysentery1 you mean8  ,,euclid3 ,yes4   
,,terpsion3 ,alas6 what a loss he will  
be6  ,,euclid3 ,yes1 ,terpsion1 he is a 
noble fellow2 only to-day ,i heard some 
people highly praising his behaviour in 
this very battle4  ,,terpsion3 ,no      
wonder2 ,i should rather be surprised at
 hearing anything else of him4 ,but why 
did he go on1 instead of stopping at    
,megara8  ,,euclid3 ,he wanted to get   
home3 although ,i entreated and advised 
him to remain1 he would not listen to   

me2 so ,i set him on his way1 and turned
 back1 and then ,i remembered what      
,socrates had said of him1 and thought  
how remarkably this1 like all his       
predictions1 had been fulfilled4 ,i     
believe that he had seen him a little   
before his own death1 when ,theaetetus  
was a youth1 and he had a memorable     
conversation with him1 which he repeated
 to me when ,i came to ,athens2 he was  
full of admiration of his genius1 and   
said that he would most certainly be a  
great man1 if he lived4  ,,terpsion3    
,the prophecy has certainly been        
fulfilled2 but what was the             
conversation8 can you tell me8          
,,euclid3 ,no1 indeed1 not offhand2 but 
,i took notes of it as soon as ,i got   
home2 these ,i filled up from memory1   
writing them out at leisure2 and        
whenever ,i went to ,athens1 ,i asked   
,socrates about any point which ,i had  
forgotten1 and on my return ,i made     
corrections2 thus ,i have nearly the    
whole conversation written down4        

,,terpsion3 ,i remember--you told me2   
and ,i have always been intending to ask
 you to show me the writing1 but have   
put off doing so2 and now1 why should we
 not read it through8--having just come 
from the country1 ,i should greatly like
 to rest4  ,,euclid3 ,i too shall be    
very glad of a rest1 for ,i went with   
,theaetetus as far as ,erineum4 ,let us 
go in1 then1 and1 while we are reposing1
 the servant shall read to us4          
,,terpsion3 ,very good4  ,,euclid3 ,here
 is the roll1 ,terpsion2 ,i may observe 
that ,i have introduced ,socrates1 not  
as narrating to me1 but as actually     
conversing with the persons whom he     
mentioned--these were1 ,theodorus the   
geometrician 7of ,cyrene71 and          
,theaetetus4 ,i have omitted1 for the   
sake of convenience1 the interlocutory  
words ',i said1' ',i remarked1' which he
 used when he spoke of himself1 and     
again1 'he agreed1' or 'disagreed1' in  
the answer1 lest the repetition of them 
should be troublesome4  ,,terpsion3     

,quite right1 ,euclid4  ,,euclid3 ,and  
now1 boy1 you may take the roll and     
read4  ,,euclid',s ,,servant ,,reads4   
,,socrates3 ,if ,i cared enough about   
the ,cyrenians1 ,theodorus1 ,i would ask
 you whether there are any rising       
geometricians or philosophers in that   
part of the world4 ,but ,i am more      
interested in our own ,athenian youth1  
and ,i would rather know who among them 
are likely to do well4 ,i observe them  
as far as ,i can myself1 and ,i enquire 
of any one whom they follow1 and ,i see 
that a great many of them follow you1 in
 which they are quite right1 considering
 your eminence in geometry and in other 
ways4 ,tell me then1 if you have met    
with any one who is good for anything4  
,,theodorus3 ,yes1 ,socrates1 ,i have   
become acquainted with one very         
remarkable ,athenian youth1 whom ,i     
commend to you as well worthy of your   
attention4 ,if he had been a beauty ,i  
should have been afraid to praise him1  
lest you should suppose that ,i was in  

love with him2 but he is no beauty1 and 
you must not be offended if ,i say that 
he is very like you2 for he has a snub  
nose and projecting eyes1 although these
 features are less marked in him than in
 you4 ,seeing1 then1 that he has no     
personal attractions1 ,i may freely say1
 that in all my acquaintance1 which is  
very large1 ,i never knew any one who   
was his equal in natural gifts3 for he  
has a quickness of apprehension which is
 almost unrivalled1 and he is           
exceedingly gentle1 and also the most   
courageous of men2 there is a union of  
qualities in him such as ,i have never  
seen in any other1 and should scarcely  
have thought possible2 for those who1   
like him1 have quick and ready and      
retentive wits1 have generally also     
quick tempers2 they are ships without   
ballast1 and go darting about1 and are  
mad rather than courageous2 and the     
steadier sort1 when they have to face   
study1 prove stupid and cannot remember4
 ,whereas he moves surely and smoothly  

and successfully in the path of         
knowledge and enquiry2 and he is full of
 gentleness1 flowing on silently like a 
river of oil2 at his age1 it is         
wonderful4  ,,socrates3 ,that is good   
news2 whose son is he8  ,,theodorus3    
,the name of his father ,i have         
forgotten1 but the youth himself is the 
middle one of those who are approaching 
us2 he and his companions have been     
anointing themselves in the outer court1
 and now they seem to have finished1 and
 are coming towards us4 ,look and see   
whether you know him4  ,,socrates3 ,i   
know the youth1 but ,i do not know his  
name2 he is the son of ,euphronius the  
,sunian1 who was himself an eminent man1
 and such another as his son is1        
according to your account of him2 ,i    
believe that he left a considerable     
fortune4  ,,theodorus3 ,theaetetus1     
,socrates1 is his name2 but ,i rather   
think that the property disappeared in  
the hands of trustees2 notwithstanding  
which he is wonderfully liberal4        

,,socrates3 ,he must be a fine fellow2  
tell him to come and sit by me4         
,,theodorus3 ,i will4 ,come hither1     
,theaetetus1 and sit by ,socrates4      
,,socrates3 ,by all means1 ,theaetetus1 
in order that ,i may see the reflection 
of myself in your face1 for ,theodorus  
says that we are alike2 and yet if each 
of us held in his hands a lyre1 and he  
said that they were tuned alike1 should 
we at once take his word1 or should we  
ask whether he who said so was or was   
not a musician8  ,,theaetetus3 ,we      
should ask4  ,,socrates3 ,and if we     
found that he was1 we should take his   
word2 and if not1 not8  ,,theaetetus3   
,true4  ,,socrates3 ,and if this        
supposed likeness of our faces is a     
matter of any interest to us1 we should 
enquire whether he who says that we are 
alike is a painter or not8              
,,theaetetus3 ,certainly we should4     
,,socrates3 ,and is ,theodorus a        
painter8  ,,theaetetus3 ,i never heard  
that he was4  ,,socrates3 ,is he a      

geometrician8  ,,theaetetus3 ,of course 
he is1 ,socrates4  ,,socrates3 ,and is  
he an astronomer and calculator and     
musician1 and in general an educated    
man8  ,,theaetetus3 ,i think so4        
,,socrates3 ,if1 then1 he remarks on a  
similarity in our persons1 either by way
 of praise or blame1 there is no        
particular reason why we should attend  
to him4  ,,theaetetus3 ,i should say    
not4  ,,socrates3 ,but if he praises the
 virtue or wisdom which are the mental  
endowments of either of us1 then he who 
hears the praises will naturally desire 
to examine him who is praised3 and he   
again should be willing to exhibit      
himself4  ,,theaetetus3 ,very true1     
,socrates4  ,,socrates3 ,then now is the
 time1 my dear ,theaetetus1 for me to   
examine1 and for you to exhibit2 since  
although ,theodorus has praised many a  
citizen and stranger in my hearing1     
never did ,i hear him praise any one as 
he has been praising you4  ,,theaetetus3
 ,i am glad to hear it1 ,socrates2 but  

what if he was only in jest8            
,,socrates3 ,nay1 ,theodorus is not     
given to jesting2 and ,i cannot allow   
you to retract your consent on any such 
pretence as that4 ,if you do1 he will   
have to swear to his words2 and we are  
perfectly sure that no one will be found
 to impugn him4 ,do not be shy then1 but
 stand to your word4  ,,theaetetus3 ,i  
suppose ,i must1 if you wish it4        
,,socrates3 ,in the first place1 ,i     
should like to ask what you learn of    
,theodorus3 something of geometry1      
perhaps8  ,,theaetetus3 ,yes4           
,,socrates3 ,and astronomy and harmony  
and calculation8  ,,theaetetus3 ,i do my
 best4  ,,socrates3 ,yes1 my boy1 and so
 do ,i2 and my desire is to learn of    
him1 or of anybody who seems to         
understand these things4 ,and ,i get on 
pretty well in general2 but there is a  
little difficulty which ,i want you and 
the company to aid me in investigating4 
,will you answer me a question3 ',is not
 learning growing wiser about that which

 you learn8'  ,,theaetetus3 ,of course4 
,,socrates3 ,and by wisdom the wise are 
wise8  ,,theaetetus3 ,yes4  ,,socrates3 
,and is that different in any way from  
knowledge8  ,,theaetetus3 ,what8        
,,socrates3 ,wisdom2 are not men wise in
 that which they know8  ,,theaetetus3   
,certainly they are4  ,,socrates3 ,then 
wisdom and knowledge are the same8      
,,theaetetus3 ,yes4  ,,socrates3 ,herein
 lies the difficulty which ,i can never 
solve to my satisfaction--,what is      
knowledge8 ,can we answer that question8
 ,what say you8 which of us will speak  
first8 whoever misses shall sit down1 as
 at a game of ball1 and shall be donkey1
 as the boys say2 he who lasts out his  
competitors in the game without missing1
 shall be our king1 and shall have the  
right of putting to us any questions    
which he pleases444,why is there no     
reply8 ,i hope1 ,theodorus1 that ,i am  
not betrayed into rudeness by my love of
 conversation8 ,i only want to make us  
talk and be friendly and sociable4      

,,theodorus3 ,the reverse of rudeness1  
,socrates3 but ,i would rather that you 
would ask one of the young fellows2 for 
the truth is1 that ,i am unused to your 
game of question and answer1 and ,i am  
too old to learn2 the young will be more
 suitable1 and they will improve more   
than ,i shall1 for youth is always able 
to improve4 ,and so having made a       
beginning with ,theaetetus1 ,i would    
advise you to go on with him and not let
 him off4  ,,socrates3 ,do you hear1    
,theaetetus1 what ,theodorus says8 ,the 
philosopher1 whom you would not like to 
disobey1 and whose word ought to be a   
command to a young man1 bids me         
interrogate you4 ,take courage1 then1   
and nobly say what you think that       
knowledge is4  ,,theaetetus3 ,well1     
,socrates1 ,i will answer as you and he 
bid me2 and if ,i make a mistake1 you   
will doubtless correct me4  ,,socrates3 
,we will1 if we can4  ,,theaetetus3     
,then1 ,i think that the sciences which 
,i learn from ,theodorus--geometry1 and 

those which you just now mentioned--are 
knowledge2 and ,i would include the art 
of the cobbler and other craftsmen2     
these1 each and all of1 them1 are       
knowledge4  ,,socrates3 ,too much1      
,theaetetus1 too much2 the nobility and 
liberality of your nature make you give 
many and diverse things1 when ,i am     
asking for one simple thing4            
,,theaetetus3 ,what do you mean1        
,socrates8  ,,socrates3 ,perhaps        
nothing4 ,i will endeavour1 however1 to 
explain what ,i believe to be my        
meaning3 ,when you speak of cobbling1   
you mean the art or science of making   
shoes8  ,,theaetetus3 ,just so4         
,,socrates3 ,and when you speak of      
carpentering1 you mean the art of making
 wooden implements8  ,,theaetetus3 ,i   
do4  ,,socrates3 ,in both cases you     
define the subject matter of each of the
 two arts8  ,,theaetetus3 ,true4        
,,socrates3 ,but that1 ,theaetetus1 was 
not the point of my question3 we wanted 
to know not the subjects1 nor yet the   

number of the arts or sciences1 for we  
were not going to count them1 but we    
wanted to know the nature of knowledge  
in the abstract4 ,am ,i not right8      
,,theaetetus3 ,perfectly right4         
,,socrates3 ,let me offer an            
illustration3 ,suppose that a person    
were to ask about some very trivial and 
obvious thing--for example1 ,what is    
clay8 and we were to reply1 that there  
is a clay of potters1 there is a clay of
 oven-makers1 there is a clay of        
brick-makers2 would not the answer be   
ridiculous8  ,,theaetetus3 ,truly4      
,,socrates3 ,in the first place1 there  
would be an absurdity in assuming that  
he who asked the question would         
understand from our answer the nature of
 'clay1' merely because we added 'of the
 image-makers1' or of any other workers4
 ,how can a man understand the name of  
anything1 when he does not know the     
nature of it8  ,,theaetetus3 ,he cannot4
  ,,socrates3 ,then he who does not know
 what science or knowledge is1 has no   

knowledge of the art or science of      
making shoes8  ,,theaetetus3 ,none4     
,,socrates3 ,nor of any other science8  
,,theaetetus3 ,no4  ,,socrates3 ,and    
when a man is asked what science or     
knowledge is1 to give in answer the name
 of some art or science is ridiculous2  
for the question is1 ',what is          
knowledge8' and he replies1 ',a         
knowledge of this or that4'             
,,theaetetus3 ,true4  ,,socrates3       
,moreover1 he might answer shortly and  
simply1 but he makes an enormous        
circuit4 ,for example1 when asked about 
the clay1 he might have said simply1    
that clay is moistened earth--what sort 
of clay is not to the point4            
,,theaetetus3 ,yes1 ,socrates1 there is 
no difficulty as you put the question4  
,you mean1 if ,i am not mistaken1       
something like what occurred to me and  
to my friend here1 your namesake        
,socrates1 in a recent discussion4      
,,socrates3 ,what was that1 ,theaetetus8
  ,,theaetetus3 ,theodorus was writing  

out for us something about roots1 such  
as the roots of three or five1 showing  
that they are incommensurable by the    
unit3 he selected other examples up to  
seventeen--there he stopped4 ,now as    
there are innumerable roots1 the notion 
occurred to us of attempting to include 
them all under one name or class4       
,,socrates3 ,and did you find such a    
class8  ,,theaetetus3 ,i think that we  
did2 but ,i should like to have your    
opinion4  ,,socrates3 ,let me hear4     
,,theaetetus3 ,we divided all numbers   
into two classes3 those which are made  
up of equal factors multiplying into one
 another1 which we compared to square   
figures and called square or equilateral
 numbers2--that was one class4          
,,socrates3 ,very good4  ,,theaetetus3  
,the intermediate numbers1 such as three
 and five1 and every other number which 
is made up of unequal factors1 either of
 a greater multiplied by a less1 or of a
 less multiplied by a greater1 and when 
regarded as a figure1 is contained in   

unequal sides2--all these we compared to
 oblong figures1 and called them oblong 
numbers4  ,,socrates3 ,capital2 and what
 followed8  ,,theaetetus3 ,the lines1 or
 sides1 which have for their squares the
 equilateral plane numbers1 were called 
by us lengths or magnitudes2 and the    
lines which are the roots of 7or whose  
squares are equal to7 the oblong        
numbers1 were called powers or roots2   
the reason of this latter name being1   
that they are commensurable with the    
former i4e41 with the so-called lengths 
or magnitudes not in linear measurement1
 but in the value of the superficial    
content of their squares2 and the same  
about solids4  ,,socrates3 ,excellent1  
my boys2 ,i think that you fully justify
 the praises of ,theodorus1 and that he 
will not be found guilty of false       
witness4  ,,theaetetus3 ,but ,i am      
unable1 ,socrates1 to give you a similar
 answer about knowledge1 which is what  
you appear to want2 and therefore       
,theodorus is a deceiver after all4     

,,socrates3 ,well1 but if some one were 
to praise you for running1 and to say   
that he never met your equal among boys1
 and afterwards you were beaten in a    
race by a grown-up man1 who was a great 
runner--would the praise be any the less
 true8  ,,theaetetus3 ,certainly not4   
,,socrates3 ,and is the discovery of the
 nature of knowledge so small a matter1 
as just now said8 ,is it not one which  
would task the powers of men perfect in 
every way8  ,,theaetetus3 ,by heaven1   
they should be the top of all           
perfection6  ,,socrates3 ,well1 then1 be
 of good cheer2 do not say that         
,theodorus was mistaken about you1 but  
do your best to ascertain the true      
nature of knowledge1 as well as of other
 things4  ,,theaetetus3 ,i am eager     
enough1 ,socrates1 if that would bring  
to light the truth4  ,,socrates3 ,come1 
you made a good beginning just now2 let 
your own answer about roots be your     
model1 and as you comprehended them all 
in one class1 try and bring the many    

sorts of knowledge under one definition4
  ,,theaetetus3 ,i can assure you1      
,socrates1 that ,i have tried very      
often1 when the report of questions     
asked by you was brought to me2 but ,i  
can neither persuade myself that ,i have
 a satisfactory answer to give1 nor hear
 of any one who answers as you would    
have him2 and ,i cannot shake off a     
feeling of anxiety4  ,,socrates3 ,these 
are the pangs of labour1 my dear        
,theaetetus2 you have something within  
you which you are bringing to the birth4
  ,,theaetetus3 ,i do not know1         
,socrates2 ,i only say what ,i feel4    
,,socrates3 ,and have you never heard1  
simpleton1 that ,i am the son of a      
midwife1 brave and burly1 whose name was
 ,phaenarete8  ,,theaetetus3 ,yes1 ,i   
have4  ,,socrates3 ,and that ,i myself  
practise midwifery8  ,,theaetetus3 ,no1 
never4  ,,socrates3 ,let me tell you    
that ,i do though1 my friend3 but you   
must not reveal the secret1 as the world
 in general have not found me out2 and  

therefore they only say of me1 that ,i  
am the strangest of mortals and drive   
men to their wits' end4 ,did you ever   
hear that too8  ,,theaetetus3 ,yes4     
,,socrates3 ,shall ,i tell you the      
reason8  ,,theaetetus3 ,by all means4   
,,socrates3 ,bear in mind the whole     
business of the midwives1 and then you  
will see my meaning better3--,no woman1 
as you are probably aware1 who is still 
able to conceive and bear1 attends other
 women1 but only those who are past     
bearing4  ,,theaetetus3 ,yes1 ,i know4  
,,socrates3 ,the reason of this is said 
to be that ,artemis--the goddess of     
childbirth--is not a mother1 and she    
honours those who are like herself2 but 
she could not allow the barren to be    
midwives1 because human nature cannot   
know the mystery of an art without      
experience2 and therefore she assigned  
this office to those who are too old to 
bear4  ,,theaetetus3 ,i dare say4       
,,socrates3 ,and ,i dare say too1 or    
rather ,i am absolutely certain1 that   

the midwives know better than others who
 is pregnant and who is not8            
,,theaetetus3 ,very true4  ,,socrates3  
,and by the use of potions and          
incantations they are able to arouse the
 pangs and to soothe them at will2 they 
can make those bear who have a          
difficulty in bearing1 and if they think
 fit they can smother the embryo in the 
womb4  ,,theaetetus3 ,they can4         
,,socrates3 ,did you ever remark that   
they are also most cunning matchmakers1 
and have a thorough knowledge of what   
unions are likely to produce a brave    
brood8  ,,theaetetus3 ,no1 never4       
,,socrates3 ,then let me tell you that  
this is their greatest pride1 more than 
cutting the umbilical cord4 ,and if you 
reflect1 you will see that the same art 
which cultivates and gathers in the     
fruits of the earth1 will be most likely
 to know in what soils the several      
plants or seeds should be deposited4    
,,theaetetus3 ,yes1 the same art4       
,,socrates3 ,and do you suppose that    

with women the case is otherwise8       
,,theaetetus3 ,i should think not4      
,,socrates3 ,certainly not2 but midwives
 are respectable women who have a       
character to lose1 and they avoid this  
department of their profession1 because 
they are afraid of being called         
procuresses1 which is a name given to   
those who join together man and woman in
 an unlawful and unscientific way2 and  
yet the true midwife is also the true   
and only matchmaker4  ,,theaetetus3     
,clearly4  ,,socrates3 ,such are the    
midwives1 whose task is a very important
 one1 but not so important as mine2 for 
women do not bring into the world at one
 time real children1 and at another time
 counterfeits which are with difficulty 
distinguished from them2 if they did1   
then the discernment of the true and    
false birth would be the crowning       
achievement of the art of midwifery--you
 would think so8  ,,theaetetus3 ,indeed 
,i should4  ,,socrates3 ,well1 my art of
 midwifery is in most respects like     

theirs2 but differs1 in that ,i attend  
men and not women2 and look after their 
souls when they are in labour1 and not  
after their bodies3 and the triumph of  
my art is in thoroughly examining       
whether the thought which the mind of   
the young man brings forth is a false   
idol or a noble and true birth4 ,and    
like the midwives1 ,i am barren1 and the
 reproach which is often made against   
me1 that ,i ask questions of others and 
have not the wit to answer them myself1 
is very just--the reason is1 that the   
god compels me to be a midwife1 but does
 not allow me to bring forth4 ,and      
therefore ,i am not myself at all wise1 
nor have ,i anything to show which is   
the invention or birth of my own soul1  
but those who converse with me profit4  
,some of them appear dull enough at     
first1 but afterwards1 as our           
acquaintance ripens1 if the god is      
gracious to them1 they all make         
astonishing progress2 and this in the   
opinion of others as well as in their   

own4 ,it is quite clear that they never 
learned anything from me2 the many fine 
discoveries to which they cling are of  
their own making4 ,but to me and the god
 they owe their delivery4 ,and the proof
 of my words is1 that many of them in   
their ignorance1 either in their        
self-conceit despising me1 or falling   
under the influence of others1 have gone
 away too soon2 and have not only lost  
the children of whom ,i had previously  
delivered them by an ill bringing up1   
but have stifled whatever else they had 
in them by evil communications1 being   
fonder of lies and shams than of the    
truth2 and they have at last ended by   
seeing themselves1 as others see them1  
to be great fools4 ,aristeides1 the son 
of ,lysimachus1 is one of them1 and     
there are many others4 ,the truants     
often return to me1 and beg that ,i     
would consort with them again--they are 
ready to go to me on their knees--and   
then1 if my familiar allows1 which is   
not always the case1 ,i receive them1   

and they begin to grow again4 ,dire are 
the pangs which my art is able to arouse
 and to allay in those who consort with 
me1 just like the pangs of women in     
childbirth2 night and day they are full 
of perplexity and travail which is even 
worse than that of the women4 ,so much  
for them4 ,and there are others1        
,theaetetus1 who come to me apparently  
having nothing in them2 and as ,i know  
that they have no need of my art1 ,i    
coax them into marrying some one1 and by
 the grace of ,god ,i can generally tell
 who is likely to do them good4 ,many of
 them ,i have given away to ,prodicus1  
and many to other inspired sages4 ,i    
tell you this long story1 friend        
,theaetetus1 because ,i suspect1 as     
indeed you seem to think yourself1 that 
you are in labour--great with some      
conception4 ,come then to me1 who am a  
midwife's son and myself a midwife1 and 
do your best to answer the questions    
which ,i will ask you4 ,and if ,i       
abstract and expose your first-born1    

because ,i discover upon inspection that
 the conception which you have formed is
 a vain shadow1 do not quarrel with me  
on that account1 as the manner of women 
is when their first children are taken  
from them4 ,for ,i have actually known  
some who were ready to bite me when ,i  
deprived them of a darling folly2 they  
did not perceive that ,i acted from     
goodwill1 not knowing that no god is the
 enemy of man--that was not within the  
range of their ideas2 neither am ,i     
their enemy in all this1 but it would be
 wrong for me to admit falsehood1 or to 
stifle the truth4 ,once more1 then1     
,theaetetus1 ,i repeat my old question1 
',what is knowledge8'--and do not say   
that you cannot tell2 but quit yourself 
like a man1 and by the help of ,god you 
will be able to tell4  ,,theaetetus3 ,at
 any rate1 ,socrates1 after such an     
exhortation ,i should be ashamed of not 
trying to do my best4 ,now he who knows 
perceives what he knows1 and1 as far as 
,i can see at present1 knowledge is     

perception4  ,,socrates3 ,bravely said1 
boy2 that is the way in which you should
 express your opinion4 ,and now1 let us 
examine together this conception of     
yours1 and see whether it is a true     
birth or a mere wind-egg3--,you say that
 knowledge is perception8  ,,theaetetus3
 ,yes4  ,,socrates3 ,well1 you have     
delivered yourself of a very important  
doctrine about knowledge2 it is indeed  
the opinion of ,protagoras1 who has     
another way of expressing it4 ,man1 he  
says1 is the measure of all things1 of  
the existence of things that are1 and of
 the non-existence of things that are   
not3--,you have read him8  ,,theaetetus3
 ,o yes1 again and again4  ,,socrates3  
,does he not say that things are to you 
such as they appear to you1 and to me   
such as they appear to me1 and that you 
and ,i are men8  ,,theaetetus3 ,yes1 he 
says so4  ,,socrates3 ,a wise man is not
 likely to talk nonsense4 ,let us try to
 understand him3 the same wind is       
blowing1 and yet one of us may be cold  

and the other not1 or one may be        
slightly and the other very cold8       
,,theaetetus3 ,quite true4  ,,socrates3 
,now is the wind1 regarded not in       
relation to us but absolutely1 cold or  
not2 or are we to say1 with ,protagoras1
 that the wind is cold to him who is    
cold1 and not to him who is not8        
,,theaetetus3 ,i suppose the last4      
,,socrates3 ,then it must appear so to  
each of them8  ,,theaetetus3 ,yes4      
,,socrates3 ,and 'appears to him' means 
the same as 'he perceives4'             
,,theaetetus3 ,true4  ,,socrates3 ,then 
appearing and perceiving coincide in the
 case of hot and cold1 and in similar   
instances2 for things appear1 or may be 
supposed to be1 to each one such as he  
perceives them8  ,,theaetetus3 ,yes4    
,,socrates3 ,then perception is always  
of existence1 and being the same as     
knowledge is unerring8  ,,theaetetus3   
,clearly4  ,,socrates3 ,in the name of  
the ,graces1 what an almighty wise man  
,protagoras must have been6 ,he spoke   

these things in a parable to the common 
herd1 like you and me1 but told the     
truth1 'his ,truth1' 7,in allusion to a 
book of ,protagoras' which bore this    
title47 in secret to his own disciples4 
,,theaetetus3 ,what do you mean1        
,socrates8  ,,socrates3 ,i am about to  
speak of a high argument1 in which all  
things are said to be relative2 you     
cannot rightly call anything by any     
name1 such as great or small1 heavy or  
light1 for the great will be small and  
the heavy light--there is no single     
thing or quality1 but out of motion and 
change and admixture all things are     
becoming relatively to one another1     
which 'becoming' is by us incorrectly   
called being1 but is really becoming1   
for nothing ever is1 but all things are 
becoming4 ,summon all                   
philosophers--,protagoras1 ,heracleitus1
 ,empedocles1 and the rest of them1 one 
after another1 and with the exception of
 ,parmenides they will agree with you in
 this4 ,summon the great masters of     

either kind of poetry--,epicharmus1 the 
prince of ,comedy1 and ,homer of        
,tragedy2 when the latter sings of      
',ocean whence sprang the gods1 and     
mother ,tethys1'  does he not mean that 
all things are the offspring1 of flux   
and motion8  ,,theaetetus3 ,i think so4 
,,socrates3 ,and who could take up arms 
against such a great army having ,homer 
for its general1 and not appear         
ridiculous8 7,compare ,cratylus47       
,,theaetetus3 ,who indeed1 ,socrates8   
,,socrates3 ,yes1 ,theaetetus2 and there
 are plenty of other proofs which will  
show that motion is the source of what  
is called being and becoming1 and       
inactivity of not-being and destruction2
 for fire and warmth1 which are supposed
 to be the parent and guardian of all   
other things1 are born of movement and  
of friction1 which is a kind of         
motion2--is not this the origin of fire8
  ,,theaetetus3 ,it is4  ,,socrates3    
,and the race of animals is generated in
 the same way8  ,,theaetetus3           

,certainly4  ,,socrates3 ,and is not the
 bodily habit spoiled by rest and       
idleness1 but preserved for a long time 
by motion and exercise8  ,,theaetetus3  
,true4  ,,socrates3 ,and what of the    
mental habit8 ,is not the soul informed1
 and improved1 and preserved by study   
and attention1 which are motions2 but   
when at rest1 which in the soul only    
means want of attention and study1 is   
uninformed1 and speedily forgets        
whatever she has learned8  ,,theaetetus3
 ,true4  ,,socrates3 ,then motion is a  
good1 and rest an evil1 to the soul as  
well as to the body8  ,,theaetetus3     
,clearly4  ,,socrates3 ,i may add1 that 
breathless calm1 stillness and the like 
waste and impair1 while wind and storm  
preserve2 and the palmary argument of   
all1 which ,i strongly urge1 is the     
golden chain in ,homer1 by which he     
means the sun1 thereby indicating that  
so long as the sun and the heavens go   
round in their orbits1 all things human 
and divine are and are preserved1 but if

 they were chained up and their motions 
ceased1 then all things would be        
destroyed1 and1 as the saying is1 turned
 upside down4  ,,theaetetus3 ,i believe1
 ,socrates1 that you have truly         
explained his meaning4  ,,socrates3     
,then now apply his doctrine to         
perception1 my good friend1 and first of
 all to vision2 that which you call     
white colour is not in your eyes1 and is
 not a distinct thing which exists out  
of them4 ,and you must not assign any   
place to it3 for if it had position it  
would be1 and be at rest1 and there     
would be no process of becoming4        
,,theaetetus3 ,then what is colour8     
,,socrates3 ,let us carry the principle 
which has just been affirmed1 that      
nothing is self-existent1 and then we   
shall see that white1 black1 and every  
other colour1 arises out of the eye     
meeting the appropriate motion1 and that
 what we call a colour is in each case  
neither the active nor the passive      
element1 but something which passes     

between them1 and is peculiar to each   
percipient2 are you quite certain that  
the several colours appear to a dog or  
to any animal whatever as they appear to
 you8  ,,theaetetus3 ,far from it4      
,,socrates3 ,or that anything appears   
the same to you as to another man8 ,are 
you so profoundly convinced of this8    
,rather would it not be true that it    
never appears exactly the same to you1  
because you are never exactly the same8 
,,theaetetus3 ,the latter4  ,,socrates3 
,and if that with which ,i compare      
myself in size1 or which ,i apprehend by
 touch1 were great or white or hot1 it  
could not become different by mere      
contact with another unless it actually 
changed2 nor again1 if the comparing or 
apprehending subject were great or white
 or hot1 could this1 when unchanged from
 within1 become changed by any          
approximation or affection of any other 
thing4 ,the fact is that in our ordinary
 way of speaking we allow ourselves to  
be driven into most ridiculous and      

wonderful contradictions1 as ,protagoras
 and all who take his line of argument  
would remark4  ,,theaetetus3 ,how8 and  
of what sort do you mean8  ,,socrates3  
,a little instance will sufficiently    
explain my meaning3 ,here are six dice1 
which are more by a half when compared  
with four1 and fewer by a half than     
twelve--they are more and also fewer4   
,how can you or any one maintain the    
contrary8  ,,theaetetus3 ,very true4    
,,socrates3 ,well1 then1 suppose that   
,protagoras or some one asks whether    
anything can become greater or more if  
not by increasing1 how would you answer 
him1 ,theaetetus8  ,,theaetetus3 ,i     
should say ',no1' ,socrates1 if ,i were 
to speak my mind in reference to this   
last question1 and if ,i were not afraid
 of contradicting my former answer4     
,,socrates3 ,capital6 excellent6 spoken 
like an oracle1 my boy6 ,and if you     
reply ',yes1' there will be a case for  
,euripides2 for our tongue will be      
unconvinced1 but not our mind4 7,in     

allusion to the well-known line of      
,euripides1 ,hippol43 e gloss omomoch e 
de thren anomotos47  ,,theaetetus3 ,very
 true4  ,,socrates3 ,the thoroughbred   
,sophists1 who know all that can be     
known about the mind1 and argue only out
 of the superfluity of their wits1 would
 have had a regular sparring-match over 
this1 and would have knocked their      
arguments together finely4 ,but you and 
,i1 who have no professional aims1 only 
desire to see what is the mutual        
relation of these principles1--whether  
they are consistent with each or not4   
,,theaetetus3 ,yes1 that would be my    
desire4  ,,socrates3 ,and mine too4 ,but
 since this is our feeling1 and there is
 plenty of time1 why should we not      
calmly and patiently review our own     
thoughts1 and thoroughly examine and see
 what these appearances in us really    
are8 ,if ,i am not mistaken1 they will  
be described by us as follows3--first1  
that nothing can become greater or less1
 either in number or magnitude1 while   

remaining equal to itself--you would    
agree8  ,,theaetetus3 ,yes4  ,,socrates3
 ,secondly1 that without addition or    
subtraction there is no increase or     
diminution of anything1 but only        
equality4  ,,theaetetus3 ,quite true4   
,,socrates3 ,thirdly1 that what was not 
before cannot be afterwards1 without    
becoming and having become4             
,,theaetetus3 ,yes1 truly4  ,,socrates3 
,these three axioms1 if ,i am not       
mistaken1 are fighting with one another 
in our minds in the case of the dice1   
or1 again1 in such a case as this--if ,i
 were to say that ,i1 who am of a       
certain height and taller than you1 may 
within a year1 without gaining or losing
 in height1 be not so tall--not that ,i 
should have lost1 but that you would    
have increased4 ,in such a case1 ,i am  
afterwards what ,i once was not1 and yet
 ,i have not become2 for ,i could not   
have become without becoming1 neither   
could ,i have become less without losing
 somewhat of my height2 and ,i could    

give you ten thousand examples of       
similar contradictions1 if we admit them
 at all4 ,i believe that you follow me1 
,theaetetus2 for ,i suspect that you    
have thought of these questions before  
now4  ,,theaetetus3 ,yes1 ,socrates1 and
 ,i am amazed when ,i think of them2 by 
the ,gods ,i am6 and ,i want to know    
what on earth they mean2 and there are  
times when my head quite swims with the 
contemplation of them4  ,,socrates3 ,i  
see1 my dear ,theaetetus1 that          
,theodorus had a true insight into your 
nature when he said that you were a     
philosopher1 for wonder is the feeling  
of a philosopher1 and philosophy begins 
in wonder4 ,he was not a bad genealogist
 who said that ,iris 7the messenger of  
heaven7 is the child of ,thaumas        
7wonder74 ,but do you begin to see what 
is the explanation of this perplexity on
 the hypothesis which we attribute to   
,protagoras8  ,,theaetetus3 ,not as yet4
  ,,socrates3 ,then you will be obliged 
to me if ,i help you to unearth the     

hidden 'truth' of a famous man or       
school4  ,,theaetetus3 ,to be sure1 ,i  
shall be very much obliged4  ,,socrates3
 ,take a look round1 then1 and see that 
none of the uninitiated are listening4  
,now by the uninitiated ,i mean the     
people who believe in nothing but what  
they can grasp in their hands1 and who  
will not allow that action or generation
 or anything invisible can have real    
existence4  ,,theaetetus3 ,yes1 indeed1 
,socrates1 they are very hard and       
impenetrable mortals4  ,,socrates3 ,yes1
 my boy1 outer barbarians4 ,far more    
ingenious are the brethren whose        
mysteries ,i am about to reveal to you4 
,their first principle is1 that all is  
motion1 and upon this all the affections
 of which we were just now speaking are 
supposed to depend3 there is nothing but
 motion1 which has two forms1 one active
 and the other passive1 both in endless 
number2 and out of the union and        
friction of them there is generated a   
progeny endless in number1 having two   

forms1 sense and the object of sense1   
which are ever breaking forth and coming
 to the birth at the same moment4 ,the  
senses are variously named hearing1     
seeing1 smelling2 there is the sense of 
heat1 cold1 pleasure1 pain1 desire1     
fear1 and many more which have names1 as
 well as innumerable others which are   
without them2 each has its kindred      
object1--each variety of colour has a   
corresponding variety of sight1 and so  
with sound and hearing1 and with the    
rest of the senses and the objects akin 
to them4 ,do you see1 ,theaetetus1 the  
bearings of this tale on the preceding  
argument8  ,,theaetetus3 ,indeed ,i do  
not4  ,,socrates3 ,then attend1 and ,i  
will try to finish the story4 ,the      
purport is that all these things are in 
motion1 as ,i was saying1 and that this 
motion is of two kinds1 a slower and a  
quicker2 and the slower elements have   
their motions in the same place and with
 reference to things near them1 and so  
they beget2 but what is begotten is     

swifter1 for it is carried to fro1 and  
moves from place to place4 ,apply this  
to sense3--,when the eye and the        
appropriate object meet together and    
give birth to whiteness and the         
sensation connatural with it1 which     
could not have been given by either of  
them going elsewhere1 then1 while the   
sight is flowing from the eye1 whiteness
 proceeds from the object which combines
 in producing the colour2 and so the eye
 is fulfilled with sight1 and really    
sees1 and becomes1 not sight1 but a     
seeing eye2 and the object which        
combined to form the colour is fulfilled
 with whiteness1 and becomes not        
whiteness but a white thing1 whether    
wood or stone or whatever the object may
 be which happens to be coloured white4 
,and this is true of all sensible       
objects1 hard1 warm1 and the like1 which
 are similarly to be regarded1 as ,i was
 saying before1 not as having any       
absolute existence1 but as being all of 
them of whatever kind generated by      

motion in their intercourse with one    
another2 for of the agent and patient1  
as existing in separation1 no           
trustworthy conception1 as they say1 can
 be formed1 for the agent has no        
existence until united with the patient1
 and the patient has no existence until 
united with the agent2 and that which by
 uniting with something becomes an      
agent1 by meeting with some other thing 
is converted into a patient4 ,and from  
all these considerations1 as ,i said at 
first1 there arises a general           
reflection1 that there is no one        
self-existent thing1 but everything is  
becoming and in relation2 and being must
 be altogether abolished1 although from 
habit and ignorance we are compelled    
even in this discussion to retain the   
use of the term4 ,but great philosophers
 tell us that we are not to allow either
 the word 'something1' or 'belonging to 
something1' or 'to me1' or 'this1' or   
'that1' or any other detaining name to  
be used1 in the language of nature all  

things are being created and destroyed1 
coming into being and passing into new  
forms2 nor can any name fix or detain   
them2 he who attempts to fix them is    
easily refuted4 ,and this should be the 
way of speaking1 not only of particulars
 but of aggregates2 such aggregates as  
are expressed in the word 'man1' or     
'stone1' or any name of an animal or of 
a class4 ,o ,theaetetus1 are not these  
speculations sweet as honey8 ,and do you
 not like the taste of them in the      
mouth8  ,,theaetetus3 ,i do not know    
what to say1 ,socrates2 for1 indeed1 ,i 
cannot make out whether you are giving  
your own opinion or only wanting to draw
 me out4  ,,socrates3 ,you forget1 my   
friend1 that ,i neither know1 nor       
profess to know1 anything of these      
matters2 you are the person who is in   
labour1 ,i am the barren midwife2 and   
this is why ,i soothe you1 and offer you
 one good thing after another1 that you 
may taste them4 ,and ,i hope that ,i may
 at last help to bring your own opinion 

into the light of day3 when this has    
been accomplished1 then we will         
determine whether what you have brought 
forth is only a wind-egg or a real and  
genuine birth4 ,therefore1 keep up your 
spirits1 and answer like a man what you 
think4  ,,theaetetus3 ,ask me4          
,,socrates3 ,then once more3 ,is it your
 opinion that nothing is but what       
becomes8--the good and the noble1 as    
well as all the other things which we   
were just now mentioning8  ,,theaetetus3
 ,when ,i hear you discoursing in this  
style1 ,i think that there is a great   
deal in what you say1 and ,i am very    
ready to assent4  ,,socrates3 ,let us   
not leave the argument unfinished1 then2
 for there still remains to be          
considered an objection which may be    
raised about dreams and diseases1 in    
particular about madness1 and the       
various illusions of hearing and sight1 
or of other senses4 ,for you know that  
in all these cases the esse-percipi     
theory appears to be unmistakably       

refuted1 since in dreams and illusions  
we certainly have false perceptions2 and
 far from saying that everything is     
which appears1 we should rather say that
 nothing is which appears4              
,,theaetetus3 ,very true1 ,socrates4    
,,socrates3 ,but then1 my boy1 how can  
any one contend that knowledge is       
perception1 or that to every man what   
appears is8  ,,theaetetus3 ,i am afraid 
to say1 ,socrates1 that ,i have nothing 
to answer1 because you rebuked me just  
now for making this excuse2 but ,i      
certainly cannot undertake to argue that
 madmen or dreamers think truly1 when   
they imagine1 some of them that they are
 gods1 and others that they can fly1 and
 are flying in their sleep4  ,,socrates3
 ,do you see another question which can 
be raised about these phenomena1 notably
 about dreaming and waking8             
,,theaetetus3 ,what question8           
,,socrates3 ,a question which ,i think  
that you must often have heard persons  
ask3--,how can you determine whether at 

this moment we are sleeping1 and all our
 thoughts are a dream2 or whether we are
 awake1 and talking to one another in   
the waking state8  ,,theaetetus3        
,indeed1 ,socrates1 ,i do not know how  
to prove the one any more than the      
other1 for in both cases the facts      
precisely correspond2--and there is no  
difficulty in supposing that during all 
this discussion we have been talking to 
one another in a dream2 and when in a   
dream we seem to be narrating dreams1   
the resemblance of the two states is    
quite astonishing4  ,,socrates3 ,you    
see1 then1 that a doubt about the       
reality of sense is easily raised1 since
 there may even be a doubt whether we   
are awake or in a dream4 ,and as our    
time is equally divided between sleeping
 and waking1 in either sphere of        
existence the soul contends that the    
thoughts which are present to our minds 
at the time are true2 and during one    
half of our lives we affirm the truth of
 the one1 and1 during the other half1 of

 the other2 and are equally confident of
 both4  ,,theaetetus3 ,most true4       
,,socrates3 ,and may not the same be    
said of madness and other disorders8 the
 difference is only that the times are  
not equal4  ,,theaetetus3 ,certainly4   
,,socrates3 ,and is truth or falsehood  
to be determined by duration of time8   
,,theaetetus3 ,that would be in many    
ways ridiculous4  ,,socrates3 ,but can  
you certainly determine by any other    
means which of these opinions is true8  
,,theaetetus3 ,i do not think that ,i   
can4  ,,socrates3 ,listen1 then1 to a   
statement of the other side of the      
argument1 which is made by the champions
 of appearance4 ,they would say1 as ,i  
imagine--,can that which is wholly other
 than something1 have the same quality  
as that from which it differs8 and      
observe1 ,theaetetus1 that the word     
'other' means not 'partially1' but      
'wholly other4'  ,,theaetetus3          
,certainly1 putting the question as you 
do1 that which is wholly other cannot   

either potentially or in any other way  
be the same4  ,,socrates3 ,and must     
therefore be admitted to be unlike8     
,,theaetetus3 ,true4  ,,socrates3 ,if1  
then1 anything happens to become like or
 unlike itself or another1 when it      
becomes like we call it the same--when  
unlike1 other8  ,,theaetetus3           
,certainly4  ,,socrates3 ,were we not   
saying that there are agents many and   
infinite1 and patients many and         
infinite8  ,,theaetetus3 ,yes4          
,,socrates3 ,and also that different    
combinations will produce results which 
are not the same1 but different8        
,,theaetetus3 ,certainly4  ,,socrates3  
,let us take you and me1 or anything as 
an example3--,there is ,socrates in     
health1 and ,socrates sick--,are they   
like or unlike8  ,,theaetetus3 ,you mean
 to compare ,socrates in health as a    
whole1 and ,socrates in sickness as a   
whole8  ,,socrates3 ,exactly2 that is my
 meaning4  ,,theaetetus3 ,i answer1 they
 are unlike4  ,,socrates3 ,and if       

unlike1 they are other8  ,,theaetetus3  
,certainly4  ,,socrates3 ,and would you 
not say the same of ,socrates sleeping  
and waking1 or in any of the states     
which we were mentioning8  ,,theaetetus3
 ,i should4  ,,socrates3 ,all agents    
have a different patient in ,socrates1  
accordingly as he is well or ill4       
,,theaetetus3 ,of course4  ,,socrates3  
,and ,i who am the patient1 and that    
which is the agent1 will produce        
something different in each of the two  
cases8  ,,theaetetus3 ,certainly4       
,,socrates3 ,the wine which ,i drink    
when ,i am in health1 appears sweet and 
pleasant to me8  ,,theaetetus3 ,true4   
,,socrates3 ,for1 as has been already   
acknowledged1 the patient and agent meet
 together and produce sweetness and a   
perception of sweetness1 which are in   
simultaneous motion1 and the perception 
which comes from the patient makes the  
tongue percipient1 and the quality of   
sweetness which arises out of and is    
moving about the wine1 makes the wine   

both to be and to appear sweet to the   
healthy tongue4  ,,theaetetus3          
,certainly2 that has been already       
acknowledged4  ,,socrates3 ,but when ,i 
am sick1 the wine really acts upon      
another and a different person8         
,,theaetetus3 ,yes4  ,,socrates3 ,the   
combination of the draught of wine1 and 
the ,socrates who is sick1 produces     
quite another result2 which is the      
sensation of bitterness in the tongue1  
and the motion and creation of          
bitterness in and about the wine1 which 
becomes not bitterness but something    
bitter2 as ,i myself become not         
perception but percipient8              
,,theaetetus3 ,true4  ,,socrates3 ,there
 is no other object of which ,i shall   
ever have the same perception1 for      
another object would give another       
perception1 and would make the          
percipient other and different2 nor can 
that object which affects me1 meeting   
another subject1 produce the same1 or   
become similar1 for that too would      

produce another result from another     
subject1 and become different4          
,,theaetetus3 ,true4  ,,socrates3       
,neither can ,i by myself1 have this    
sensation1 nor the object by itself1    
this quality4  ,,theaetetus3 ,certainly 
not4  ,,socrates3 ,when ,i perceive ,i  
must become percipient of               
something--there can be no such thing as
 perceiving and perceiving nothing2 the 
object1 whether it become sweet1 bitter1
 or of any other quality1 must have     
relation to a percipient2 nothing can   
become sweet which is sweet to no one4  
,,theaetetus3 ,certainly not4           
,,socrates3 ,then the inference is1 that
 we 7the agent and patient7 are or      
become in relation to one another2 there
 is a law which binds us one to the     
other1 but not to any other existence1  
nor each of us to himself2 and therefore
 we can only be bound to one another2 so
 that whether a person says that a thing
 is or becomes1 he must say that it is  
or becomes to or of or in relation to   

something else2 but he must not say or  
allow any one else to say that anything 
is or becomes absolutely3--such is our  
conclusion4  ,,theaetetus3 ,very true1  
,socrates4  ,,socrates3 ,then1 if that  
which acts upon me has relation to me   
and to no other1 ,i and no other am the 
percipient of it8  ,,theaetetus3 ,of    
course4  ,,socrates3 ,then my perception
 is true to me1 being inseparable from  
my own being2 and1 as ,protagoras says1 
to myself ,i am judge of what is and    
what is not to me4  ,,theaetetus3 ,i    
suppose so4  ,,socrates3 ,how then1 if  
,i never err1 and if my mind never trips
 in the conception of being or becoming1
 can ,i fail of knowing that which ,i   
perceive8  ,,theaetetus3 ,you cannot4   
,,socrates3 ,then you were quite right  
in affirming that knowledge is only     
perception2 and the meaning turns out to
 be the same1 whether with ,homer and   
,heracleitus1 and all that company1 you 
say that all is motion and flux1 or with
 the great sage ,protagoras1 that man is

 the measure of all things2 or with     
,theaetetus1 that1 given these premises1
 perception is knowledge4 ,am ,i not    
right1 ,theaetetus1 and is not this your
 new-born child1 of which ,i have       
delivered you8 ,what say you8           
,,theaetetus3 ,i cannot but agree1      
,socrates4  ,,socrates3 ,then this is   
the child1 however he may turn out1     
which you and ,i have with difficulty   
brought into the world4 ,and now that he
 is born1 we must run round the hearth  
with him1 and see whether he is worth   
rearing1 or is only a wind-egg and a    
sham4 ,is he to be reared in any case1  
and not exposed8 or will you bear to see
 him rejected1 and not get into a       
passion if ,i take away your first-born8
  ,,theodorus3 ,theaetetus will not be  
angry1 for he is very good-natured4 ,but
 tell me1 ,socrates1 in heaven's name1  
is this1 after all1 not the truth8      
,,socrates3 ,you1 ,theodorus1 are a     
lover of theories1 and now you          
innocently fancy that ,i am a bag full  

of them1 and can easily pull one out    
which will overthrow its predecessor4   
,but you do not see that in reality none
 of these theories come from me2 they   
all come from him who talks with me4 ,i 
only know just enough to extract them   
from the wisdom of another1 and to      
receive them in a spirit of fairness4   
,and now ,i shall say nothing myself1   
but shall endeavour to elicit something 
from our young friend4  ,,theodorus3 ,do
 as you say1 ,socrates2 you are quite   
right4  ,,socrates3 ,shall ,i tell you1 
,theodorus1 what amazes me in your      
acquaintance ,protagoras8  ,,theodorus3 
,what is it8  ,,socrates3 ,i am charmed 
with his doctrine1 that what appears is 
to each one1 but ,i wonder that he did  
not begin his book on ,truth with a     
declaration that a pig or a dog-faced   
baboon1 or some other yet stranger      
monster which has sensation1 is the     
measure of all things2 then he might    
have shown a magnificent contempt for   
our opinion of him by informing us at   

the outset that while we were           
reverencing him like a ,god for his     
wisdom he was no better than a tadpole1 
not to speak of his fellow-men--would   
not this have produced an overpowering  
effect8 ,for if truth is only sensation1
 and no man can discern another's       
feelings better than he1 or has any     
superior right to determine whether his 
opinion is true or false1 but each1 as  
we have several times repeated1 is to   
himself the sole judge1 and everything  
that he judges is true and right1 why1  
my friend1 should ,protagoras be        
preferred to the place of wisdom and    
instruction1 and deserve to be well     
paid1 and we poor ignoramuses have to go
 to him1 if each one is the measure of  
his own wisdom8 ,must he not be talking 
'ad captandum' in all this8 ,i say      
nothing of the ridiculous predicament in
 which my own midwifery and the whole   
art of dialectic is placed2 for the     
attempt to supervise or refute the      
notions or opinions of others would be a

 tedious and enormous piece of folly1 if
 to each man his own are right2 and this
 must be the case if ,protagoras' ,truth
 is the real truth1 and the philosopher 
is not merely amusing himself by giving 
oracles out of the shrine of his book4  
,,theodorus3 ,he was a friend of mine1  
,socrates1 as you were saying1 and      
therefore ,i cannot have him refuted by 
my lips1 nor can ,i oppose you when ,i  
agree with you2 please1 then1 to take   
,theaetetus again2 he seemed to answer  
very nicely4  ,,socrates3 ,if you were  
to go into a ,lacedaemonian palestra1   
,theodorus1 would you have a right to   
look on at the naked wrestlers1 some of 
them making a poor figure1 if you did   
not strip and give them an opportunity  
of judging of your own person8          
,,theodorus3 ,why not1 ,socrates1 if    
they would allow me1 as ,i think you    
will1 in consideration of my age and    
stiffness2 let some more supple youth   
try a fall with you1 and do not drag me 
into the gymnasium4  ,,socrates3 ,your  

will is my will1 ,theodorus1 as the     
proverbial philosophers say1 and        
therefore ,i will return to the sage    
,theaetetus3 ,tell me1 ,theaetetus1 in  
reference to what ,i was saying1 are you
 not lost in wonder1 like myself1 when  
you find that all of a sudden you are   
raised to the level of the wisest of    
men1 or indeed of the gods8--for you    
would assume the measure of ,protagoras 
to apply to the gods as well as men8    
,,theaetetus3 ,certainly ,i should1 and 
,i confess to you that ,i am lost in    
wonder4 ,at first hearing1 ,i was quite 
satisfied with the doctrine1 that       
whatever appears is to each one1 but now
 the face of things has changed4        
,,socrates3 ,why1 my dear boy1 you are  
young1 and therefore your ear is quickly
 caught and your mind influenced by     
popular arguments4 ,protagoras1 or some 
one speaking on his behalf1 will        
doubtless say in reply1--,good people1  
young and old1 you meet and harangue1   
and bring in the gods1 whose existence  

or non-existence ,i banish from writing 
and speech1 or you talk about the reason
 of man being degraded to the level of  
the brutes1 which is a telling argument 
with the multitude1 but not one word of 
proof or demonstration do you offer4    
,all is probability with you1 and yet   
surely you and ,theodorus had better    
reflect whether you are disposed to     
admit of probability and figures of     
speech in matters of such importance4   
,he or any other mathematician who      
argued from probabilities and           
likelihoods in geometry1 would not be   
worth an ace4  ,,theaetetus3 ,but       
neither you nor we1 ,socrates1 would be 
satisfied with such arguments4          
,,socrates3 ,then you and ,theodorus    
mean to say that we must look at the    
matter in some other way8  ,,theaetetus3
 ,yes1 in quite another way4            
,,socrates3 ,and the way will be to ask 
whether perception is or is not the same
 as knowledge2 for this was the real    
point of our argument1 and with a view  

to this we raised 7did we not87 those   
many strange questions4  ,,theaetetus3  
,certainly4  ,,socrates3 ,shall we say  
that we know every thing which we see   
and hear8 for example1 shall we say that
 not having learned1 we do not hear the 
language of foreigners when they speak  
to us8 or shall we say that we not only 
hear1 but know what they are saying8 ,or
 again1 if we see letters which we do   
not understand1 shall we say that we do 
not see them8 or shall we aver that1    
seeing them1 we must know them8         
,,theaetetus3 ,we shall say1 ,socrates1 
that we know what we actually see and   
hear of them--that is to say1 we see and
 know the figure and colour of the      
letters1 and we hear and know the       
elevation or depression of the sound of 
them2 but we do not perceive by sight   
and hearing1 or know1 that which        
grammarians and interpreters teach about
 them4  ,,socrates3 ,capital1           
,theaetetus2 and about this there shall 
be no dispute1 because ,i want you to   

grow2 but there is another difficulty   
coming1 which you will also have to     
repulse4  ,,theaetetus3 ,what is it8    
,,socrates3 ,some one will say1 ,can a  
man who has ever known anything1 and    
still has and preserves a memory of that
 which he knows1 not know that which he 
remembers at the time when he remembers8
 ,i have1 ,i fear1 a tedious way of     
putting a simple question1 which is     
only1 whether a man who has learned1 and
 remembers1 can fail to know8           
,,theaetetus3 ,impossible1 ,socrates2   
the supposition is monstrous4           
,,socrates3 ,am ,i talking nonsense1    
then8 ,think3 is not seeing perceiving1 
and is not sight perception8            
,,theaetetus3 ,true4  ,,socrates3 ,and  
if our recent definition holds1 every   
man knows that which he has seen8       
,,theaetetus3 ,yes4  ,,socrates3 ,and   
you would admit that there is such a    
thing as memory8  ,,theaetetus3 ,yes4   
,,socrates3 ,and is memory of something 
or of nothing8  ,,theaetetus3 ,of       

something1 surely4  ,,socrates3 ,of     
things learned and perceived1 that is8  
,,theaetetus3 ,certainly4  ,,socrates3  
,often a man remembers that which he has
 seen8  ,,theaetetus3 ,true4            
,,socrates3 ,and if he closed his eyes1 
would he forget8  ,,theaetetus3 ,who1   
,socrates1 would dare to say so8        
,,socrates3 ,but we must say so1 if the 
previous argument is to be maintained4  
,,theaetetus3 ,what do you mean8 ,i am  
not quite sure that ,i understand you1  
though ,i have a strong suspicion that  
you are right4  ,,socrates3 ,as thus3 he
 who sees knows1 as we say1 that which  
he sees2 for perception and sight and   
knowledge are admitted to be the same4  
,,theaetetus3 ,certainly4  ,,socrates3  
,but he who saw1 and has knowledge of   
that which he saw1 remembers1 when he   
closes his eyes1 that which he no longer
 sees4  ,,theaetetus3 ,true4            
,,socrates3 ,and seeing is knowing1 and 
therefore not-seeing is not-knowing8    
,,theaetetus3 ,very true4  ,,socrates3  

,then the inference is1 that a man may  
have attained the knowledge of          
something1 which he may remember and yet
 not know1 because he does not see2 and 
this has been affirmed by us to be a    
monstrous supposition4  ,,theaetetus3   
,most true4  ,,socrates3 ,thus1 then1   
the assertion that knowledge and        
perception are one1 involves a manifest 
impossibility8  ,,theaetetus3 ,yes4     
,,socrates3 ,then they must be          
distinguished8  ,,theaetetus3 ,i suppose
 that they must4  ,,socrates3 ,once more
 we shall have to begin1 and ask ',what 
is knowledge8' and yet1 ,theaetetus1    
what are we going to do8  ,,theaetetus3 
,about what8  ,,socrates3 ,like a       
good-for-nothing cock1 without having   
won the victory1 we walk away from the  
argument and crow4  ,,theaetetus3 ,how  
do you mean8  ,,socrates3 ,after the    
manner of disputers 7,lys42 ,phaedo2    
,republic71 we were satisfied with mere 
verbal consistency1 and were well       
pleased if in this way we could gain an 

advantage4 ,although professing not to  
be mere ,eristics1 but philosophers1 ,i 
suspect that we have unconsciously      
fallen into the error of that ingenious 
class of persons4  ,,theaetetus3 ,i do  
not as yet understand you4  ,,socrates3 
,then ,i will try to explain myself3    
just now we asked the question1 whether 
a man who had learned and remembered    
could fail to know1 and we showed that a
 person who had seen might remember when
 he had his eyes shut and could not see1
 and then he would at the same time     
remember and not know4 ,but this was an 
impossibility4 ,and so the ,protagorean 
fable came to nought1 and yours also1   
who maintained that knowledge is the    
same as perception4  ,,theaetetus3      
,true4  ,,socrates3 ,and yet1 my friend1
 ,i rather suspect that the result would
 have been different if ,protagoras1 who
 was the father of the first of the two 
brats1 had been alive2 he would have had
 a great deal to say on their behalf4   
,but he is dead1 and we insult over his 

orphan child2 and even the guardians    
whom he left1 and of whom our friend    
,theodorus is one1 are unwilling to give
 any help1 and therefore ,i suppose that
 ,i must take up his cause myself1 and  
see justice done8  ,,theodorus3 ,not ,i1
 ,socrates1 but rather ,callias1 the son
 of ,hipponicus1 is guardian of his     
orphans4 ,i was too soon diverted from  
the abstractions of dialectic to        
geometry4 ,nevertheless1 ,i shall be    
grateful to you if you assist him4      
,,socrates3 ,very good1 ,theodorus2 you 
shall see how ,i will come to the       
rescue4 ,if a person does not attend to 
the meaning of terms as they are        
commonly used in argument1 he may be    
involved even in greater paradoxes than 
these4 ,shall ,i explain this matter to 
you or to ,theaetetus8  ,,theodorus3 ,to
 both of us1 and let the younger answer2
 he will incur less disgrace if he is   
discomfited4  ,,socrates3 ,then now let 
me ask the awful question1 which is     
this3--,can a man know and also not know

 that which he knows8  ,,theodorus3 ,how
 shall we answer1 ,theaetetus8          
,,theaetetus3 ,he cannot1 ,i should say4
  ,,socrates3 ,he can1 if you maintain  
that seeing is knowing4 ,when you are   
imprisoned in a well1 as the saying is1 
and the self-assured adversary closes   
one of your eyes with his hand1 and asks
 whether you can see his cloak with the 
eye which he has closed1 how will you   
answer the inevitable man8              
,,theaetetus3 ,i should answer1 ',not   
with that eye but with the other4'      
,,socrates3 ,then you see and do not see
 the same thing at the same time4       
,,theaetetus3 ,yes1 in a certain sense4 
,,socrates3 ,none of that1 he will      
reply2 ,i do not ask or bid you answer  
in what sense you know1 but only whether
 you know that which you do not know4   
,you have been proved to see that which 
you do not see2 and you have already    
admitted that seeing is knowing1 and    
that not-seeing is not-knowing3 ,i leave
 you to draw the inference4             

,,theaetetus3 ,yes2 the inference is the
 contradictory of my assertion4         
,,socrates3 ,yes1 my marvel1 and there  
might have been yet worse things in     
store for you1 if an opponent had gone  
on to ask whether you can have a sharp  
and also a dull knowledge1 and whether  
you can know near1 but not at a         
distance1 or know the same thing with   
more or less intensity1 and so on       
without end4 ,such questions might have 
been put to you by a light-armed        
mercenary1 who argued for pay4 ,he would
 have lain in wait for you1 and when you
 took up the position1 that sense is    
knowledge1 he would have made an assault
 upon hearing1 smelling1 and the other  
senses2--he would have shown you no     
mercy2 and while you were lost in envy  
and admiration of his wisdom1 he would  
have got you into his net1 out of which 
you would not have escaped until you had
 come to an understanding about the sum 
to be paid for your release4 ,well1 you 
ask1 and how will ,protagoras reinforce 

his position8 ,shall ,i answer for him8 
,,theaetetus3 ,by all means4            
,,socrates3 ,he will repeat all those   
things which we have been urging on his 
behalf1 and then he will close with us  
in disdain1 and say3--,the worthy       
,socrates asked a little boy1 whether   
the same man could remember and not know
 the same thing1 and the boy said ,no1  
because he was frightened1 and could not
 see what was coming1 and then ,socrates
 made fun of poor me4 ,the truth is1 ,o 
slatternly ,socrates1 that when you ask 
questions about any assertion of mine1  
and the person asked is found tripping1 
if he has answered as ,i should have    
answered1 then ,i am refuted1 but if he 
answers something else1 then he is      
refuted and not ,i4 ,for do you really  
suppose that any one would admit the    
memory which a man has of an impression 
which has passed away to be the same    
with that which he experienced at the   
time8 ,assuredly not4 ,or would he      
hesitate to acknowledge that the same   

man may know and not know the same      
thing8 ,or1 if he is afraid of making   
this admission1 would he ever grant that
 one who has become unlike is the same  
as before he became unlike8 ,or would he
 admit that a man is one at all1 and not
 rather many and infinite as the changes
 which take place in him8 ,i speak by   
the card in order to avoid entanglements
 of words4 ,but1 ,o my good sir1 he will
 say1 come to the argument in a more    
generous spirit2 and either show1 if you
 can1 that our sensations are not       
relative and individual1 or1 if you     
admit them to be so1 prove that this    
does not involve the consequence that   
the appearance becomes1 or1 if you will 
have the word1 is1 to the individual    
only4 ,as to your talk about pigs and   
baboons1 you are yourself behaving like 
a pig1 and you teach your hearers to    
make sport of my writings in the same   
ignorant manner2 but this is not to your
 credit4 ,for ,i declare that the truth 
is as ,i have written1 and that each of 

us is a measure of existence and of     
non-existence4 ,yet one man may be a    
thousand times better than another in   
proportion as different things are and  
appear to him4 ,and ,i am far from      
saying that wisdom and the wise man have
 no existence2 but ,i say that the wise 
man is he who makes the evils which     
appear and are to a man1 into goods     
which are and appear to him4 ,and ,i    
would beg you not to press my words in  
the letter1 but to take the meaning of  
them as ,i will explain them4 ,remember 
what has been already said1--that to the
 sick man his food appears to be and is 
bitter1 and to the man in health the    
opposite of bitter4 ,now ,i cannot      
conceive that one of these men can be or
 ought to be made wiser than the other3 
nor can you assert that the sick man    
because he has one impression is        
foolish1 and the healthy man because he 
has another is wise2 but the one state  
requires to be changed into the other1  
the worse into the better4 ,as in       

education1 a change of state has to be  
effected1 and the sophist accomplishes  
by words the change which the physician 
works by the aid of drugs4 ,not that any
 one ever made another think truly1 who 
previously thought falsely4 ,for no one 
can think what is not1 or1 think        
anything different from that which he   
feels2 and this is always true4 ,but as 
the inferior habit of mind has thoughts 
of kindred nature1 so ,i conceive that a
 good mind causes men to have good      
thoughts2 and these which the           
inexperienced call true1 ,i maintain to 
be only better1 and not truer than      
others4 ,and1 ,o my dear ,socrates1 ,i  
do not call wise men tadpoles3 far from 
it2 ,i say that they are the physicians 
of the human body1 and the husbandmen of
 plants--for the husbandmen also take   
away the evil and disordered sensations 
of plants1 and infuse into them good and
 healthy sensations--aye and true ones2 
and the wise and good rhetoricians make 
the good instead of the evil to seem    

just to states2 for whatever appears to 
a state to be just and fair1 so long as 
it is regarded as such1 is just and fair
 to it2 but the teacher of wisdom causes
 the good to take the place of the evil1
 both in appearance and in reality4 ,and
 in like manner the ,sophist who is able
 to train his pupils in this spirit is a
 wise man1 and deserves to be well paid 
by them4 ,and so one man is wiser than  
another2 and no one thinks falsely1 and 
you1 whether you will or not1 must      
endure to be a measure4 ,on these       
foundations the argument stands firm1   
which you1 ,socrates1 may1 if you       
please1 overthrow by an opposite        
argument1 or if you like you may put    
questions to me--a method to which no   
intelligent person will object1 quite   
the reverse4 ,but ,i must beg you to put
 fair questions3 for there is great     
inconsistency in saying that you have a 
zeal for virtue1 and then always        
behaving unfairly in argument4 ,the     
unfairness of which ,i complain is that 

you do not distinguish between mere     
disputation and dialectic3 the disputer 
may trip up his opponent as often as he 
likes1 and make fun2 but the            
dialectician will be in earnest1 and    
only correct his adversary when         
necessary1 telling him the errors into  
which he has fallen through his own     
fault1 or that of the company which he  
has previously kept4 ,if you do so1 your
 adversary will lay the blame of his own
 confusion and perplexity on himself1   
and not on you4 ,he will follow and love
 you1 and will hate himself1 and escape 
from himself into philosophy1 in order  
that he may become different from what  
he was4 ,but the other mode of arguing1 
which is practised by the many1 will    
have just the opposite effect upon him2 
and as he grows older1 instead of       
turning philosopher1 he will come to    
hate philosophy4 ,i would recommend you1
 therefore1 as ,i said before1 not to   
encourage yourself in this polemical and
 controversial temper1 but to find out1 

in a friendly and congenial spirit1 what
 we really mean when we say that all    
things are in motion1 and that to every 
individual and state what appears1 is4  
,in this manner you will consider       
whether knowledge and sensation are the 
same or different1 but you will not     
argue1 as you were just now doing1 from 
the customary use of names and words1   
which the vulgar pervert in all sorts of
 ways1 causing infinite perplexity to   
one another4 ,such1 ,theodorus1 is the  
very slight help which ,i am able to    
offer to your old friend2 had he been   
living1 he would have helped himself in 
a far more gloriose style4  ,,theodorus3
 ,you are jesting1 ,socrates2 indeed1   
your defence of him has been most       
valorous4  ,,socrates3 ,thank you1      
friend2 and ,i hope that you observed   
,protagoras bidding us be serious1 as   
the text1 ',man is the measure of all   
things1' was a solemn one2 and he       
reproached us with making a boy the     
medium of discourse1 and said that the  

boy's timidity was made to tell against 
his argument2 he also declared that we  
made a joke of him4  ,,theodorus3 ,how  
could ,i fail to observe all that1      
,socrates8  ,,socrates3 ,well1 and shall
 we do as he says8  ,,theodorus3 ,by all
 means4  ,,socrates3 ,but if his wishes 
are to be regarded1 you and ,i must take
 up the argument1 and in all            
seriousness1 and ask and answer one     
another1 for you see that the rest of us
 are nothing but boys4 ,in no other way 
can we escape the imputation1 that in   
our fresh analysis of his thesis we are 
making fun with boys4  ,,theodorus3     
,well1 but is not ,theaetetus better    
able to follow a philosophical enquiry  
than a great many men who have long     
beards8  ,,socrates3 ,yes1 ,theodorus1  
but not better than you2 and therefore  
please not to imagine that ,i am to     
defend by every means in my power your  
departed friend2 and that you are to    
defend nothing and nobody4 ,at any rate1
 my good man1 do not sheer off until we 

know whether you are a true measure of  
diagrams1 or whether all men are equally
 measures and sufficient for themselves 
in astronomy and geometry1 and the other
 branches of knowledge in which you are 
supposed to excel them4  ,,theodorus3   
,he who is sitting by you1 ,socrates1   
will not easily avoid being drawn into  
an argument2 and when ,i said just now  
that you would excuse me1 and not1 like 
the ,lacedaemonians1 compel me to strip 
and fight1 ,i was talking nonsense--,i  
should rather compare you to ,scirrhon1 
who threw travellers from the rocks2 for
 the ,lacedaemonian rule is 'strip or   
depart1' but you seem to go about your  
work more after the fashion of ,antaeus3
 you will not allow any one who         
approaches you to depart until you have 
stripped him1 and he has been compelled 
to try a fall with you in argument4     
,,socrates3 ,there1 ,theodorus1 you have
 hit off precisely the nature of my     
complaint2 but ,i am even more          
pugnacious than the giants of old1 for  

,i have met with no end of heroes2 many 
a ,heracles1 many a ,theseus1 mighty in 
words1 has broken my head2 nevertheless 
,i am always at this rough exercise1    
which inspires me like a passion4       
,please1 then1 to try a fall with me1   
whereby you will do yourself good as    
well as me4  ,,theodorus3 ,i consent2   
lead me whither you will1 for ,i know   
that you are like destiny2 no man can   
escape from any argument which you may  
weave for him4 ,but ,i am not disposed  
to go further than you suggest4         
,,socrates3 ,once will be enough2 and   
now take particular care that we do not 
again unwittingly expose ourselves to   
the reproach of talking childishly4     
,,theodorus3 ,i will do my best to avoid
 that error4  ,,socrates3 ,in the first 
place1 let us return to our old         
objection1 and see whether we were right
 in blaming and taking offence at       
,protagoras on the ground that he       
assumed all to be equal and sufficient  
in wisdom2 although he admitted that    

there was a better and worse1 and that  
in respect of this1 some who as he said 
were the wise excelled others4          
,,theodorus3 ,very true4  ,,socrates3   
,had ,protagoras been living and        
answered for himself1 instead of our    
answering for him1 there would have been
 no need of our reviewing or reinforcing
 the argument4 ,but as he is not here1  
and some one may accuse us of speaking  
without authority on his behalf1 had we 
not better come to a clearer agreement  
about his meaning1 for a great deal may 
be at stake8  ,,theodorus3 ,true4       
,,socrates3 ,then let us obtain1 not    
through any third person1 but from his  
own statement and in the fewest words   
possible1 the basis of agreement4       
,,theodorus3 ,in what way8  ,,socrates3 
,in this way3--,his words are1 ',what   
seems to a man1 is to him4'             
,,theodorus3 ,yes1 so he says4          
,,socrates3 ,and are not we1            
,protagoras1 uttering the opinion of    
man1 or rather of all mankind1 when we  

say that every one thinks himself wiser 
than other men in some things1 and their
 inferior in others8 ,in the hour of    
danger1 when they are in perils of war1 
or of the sea1 or of sickness1 do they  
not look up to their commanders as if   
they were gods1 and expect salvation    
from them1 only because they excel them 
in knowledge8 ,is not the world full of 
men in their several employments1 who   
are looking for teachers and rulers of  
themselves and of the animals8 and there
 are plenty who think that they are able
 to teach and able to rule4 ,now1 in all
 this is implied that ignorance and     
wisdom exist among them1 at least in    
their own opinion4  ,,theodorus3        
,certainly4  ,,socrates3 ,and wisdom is 
assumed by them to be true thought1 and 
ignorance to be false opinion4          
,,theodorus3 ,exactly4  ,,socrates3 ,how
 then1 ,protagoras1 would you have us   
treat the argument8 ,shall we say that  
the opinions of men are always true1 or 
sometimes true and sometimes false8 ,in 

either case1 the result is the same1 and
 their opinions are not always true1 but
 sometimes true and sometimes false4    
,for tell me1 ,theodorus1 do you suppose
 that you yourself1 or any other        
follower of ,protagoras1 would contend  
that no one deems another ignorant or   
mistaken in his opinion8  ,,theodorus3  
,the thing is incredible1 ,socrates4    
,,socrates3 ,and yet that absurdity is  
necessarily involved in the thesis which
 declares man to be the measure of all  
things4  ,,theodorus3 ,how so8          
,,socrates3 ,why1 suppose that you      
determine in your own mind something to 
be true1 and declare your opinion to me2
 let us assume1 as he argues1 that this 
is true to you4 ,now1 if so1 you must   
either say that the rest of us are not  
the judges of this opinion or judgment  
of yours1 or that we judge you always to
 have a true opinion8 ,but are there not
 thousands upon thousands who1 whenever 
you form a judgment1 take up arms       
against you and are of an opposite      

judgment and opinion1 deeming that you  
judge falsely8  ,,theodorus3 ,yes1      
indeed1 ,socrates1 thousands and tens of
 thousands1 as ,homer says1 who give me 
a world of trouble4  ,,socrates3 ,well1 
but are we to assert that what you think
 is true to you and false to the ten    
thousand others8  ,,theodorus3 ,no other
 inference seems to be possible4        
,,socrates3 ,and how about ,protagoras  
himself8 ,if neither he nor the         
multitude thought1 as indeed they do not
 think1 that man is the measure of all  
things1 must it not follow that the     
truth of which ,protagoras wrote would  
be true to no one8 ,but if you suppose  
that he himself thought this1 and that  
the multitude does not agree with him1  
you must begin by allowing that in      
whatever proportion the many are more   
than one1 in that proportion his truth  
is more untrue than true4  ,,theodorus3 
,that would follow if the truth is      
supposed to vary with individual        
opinion4  ,,socrates3 ,and the best of  

the joke is1 that he acknowledges the   
truth of their opinion who believe his  
own opinion to be false2 for he admits  
that the opinions of all men are true4  
,,theodorus3 ,certainly4  ,,socrates3   
,and does he not allow that his own     
opinion is false1 if he admits that the 
opinion of those who think him false is 
true8  ,,theodorus3 ,of course4         
,,socrates3 ,whereas the other side do  
not admit that they speak falsely8      
,,theodorus3 ,they do not4  ,,socrates3 
,and he1 as may be inferred from his    
writings1 agrees that this opinion is   
also true4  ,,theodorus3 ,clearly4      
,,socrates3 ,then all mankind1 beginning
 with ,protagoras1 will contend1 or     
rather1 ,i should say that he will      
allow1 when he concedes that his        
adversary has a true                    
opinion--,protagoras1 ,i say1 will      
himself allow that neither a dog nor any
 ordinary man is the measure of anything
 which he has not learned--am ,i not    
right8  ,,theodorus3 ,yes4  ,,socrates3 

,and the truth of ,protagoras being     
doubted by all1 will be true neither to 
himself to any one else8  ,,theodorus3  
,i think1 ,socrates1 that we are running
 my old friend too hard4  ,,socrates3   
,but ,i do not know that we are going   
beyond the truth4 ,doubtless1 as he is  
older1 he may be expected to be wiser   
than we are4 ,and if he could only just 
get his head out of the world below1 he 
would have overthrown both of us again  
and again1 me for talking nonsense and  
you for assenting to me1 and have been  
off and underground in a trice4 ,but as 
he is not within call1 we must make the 
best use of our own faculties1 such as  
they are1 and speak out what appears to 
us to be true4 ,and one thing which no  
one will deny is1 that there are great  
differences in the understandings of    
men4  ,,theodorus3 ,in that opinion ,i  
quite agree4  ,,socrates3 ,and is there 
not most likely to be firm ground in the
 distinction which we were indicating on
 behalf of ,protagoras1 viz4 that most  

things1 and all immediate sensations1   
such as hot1 dry1 sweet1 are only such  
as they appear2 if however difference of
 opinion is to be allowed at all1 surely
 we must allow it in respect of health  
or disease8 for every woman1 child1 or  
living creature has not such a knowledge
 of what conduces to health as to enable
 them to cure themselves4  ,,theodorus3 
,i quite agree4  ,,socrates3 ,or again1 
in politics1 while affirming that just  
and unjust1 honourable and disgraceful1 
holy and unholy1 are in reality to each 
state such as the state thinks and makes
 lawful1 and that in determining these  
matters no individual or state is wiser 
than another1 still the followers of    
,protagoras will not deny that in       
determining what is or is not expedient 
for the community one state is wiser and
 one counsellor better than             
another--they will scarcely venture to  
maintain1 that what a city enacts in the
 belief that it is expedient will always
 be really expedient4 ,but in the other 

case1 ,i mean when they speak of justice
 and injustice1 piety and impiety1 they 
are confident that in nature these have 
no existence or essence of their        
own--the truth is that which is agreed  
on at the time of the agreement1 and as 
long as the agreement lasts2 and this is
 the philosophy of many who do not      
altogether go along with ,protagoras4   
,here arises a new question1 ,theodorus1
 which threatens to be more serious than
 the last4  ,,theodorus3 ,well1         
,socrates1 we have plenty of leisure4   
,,socrates3 ,that is true1 and your     
remark recalls to my mind an observation
 which ,i have often made1 that those   
who have passed their days in the       
pursuit of philosophy are ridiculously  
at fault when they have to appear and   
speak in court4 ,how natural is this6   
,,theodorus3 ,what do you mean8         
,,socrates3 ,i mean to say1 that those  
who have been trained in philosophy and 
liberal pursuits are as unlike those who
 from their youth upwards have been     

knocking about in the courts and such   
places1 as a freeman is in breeding     
unlike a slave4  ,,theodorus3 ,in what  
is the difference seen8  ,,socrates3 ,in
 the leisure spoken of by you1 which a  
freeman can always command3 he has his  
talk out in peace1 and1 like ourselves1 
he wanders at will from one subject to  
another1 and from a second to a         
third1--if the fancy takes him1 he      
begins again1 as we are doing now1      
caring not whether his words are many or
 few2 his only aim is to attain the     
truth4 ,but the lawyer is always in a   
hurry2 there is the water of the        
clepsydra driving him on1 and not       
allowing him to expatiate at will3 and  
there is his adversary standing over    
him1 enforcing his rights2 the          
indictment1 which in their phraseology  
is termed the affidavit1 is recited at  
the time3 and from this he must not     
deviate4 ,he is a servant1 and is       
continually disputing about a           
fellow-servant before his master1 who is

 seated1 and has the cause in his hands2
 the trial is never about some          
indifferent matter1 but always concerns 
himself2 and often the race is for his  
life4 ,the consequence has been1 that he
 has become keen and shrewd2 he has     
learned how to flatter his master in    
word and indulge him in deed2 but his   
soul is small and unrighteous4 ,his     
condition1 which has been that of a     
slave from his youth upwards1 has       
deprived him of growth and uprightness  
and independence2 dangers and fears1    
which were too much for his truth and   
honesty1 came upon him in early years1  
when the tenderness of youth was unequal
 to them1 and he has been driven into   
crooked ways2 from the first he has     
practised deception and retaliation1 and
 has become stunted and warped4 ,and so 
he has passed out of youth into manhood1
 having no soundness in him2 and is now1
 as he thinks1 a master in wisdom4 ,such
 is the lawyer1 ,theodorus4 ,will you   
have the companion picture of the       

philosopher1 who is of our brotherhood2 
or shall we return to the argument8 ,do 
not let us abuse the freedom of         
digression which we claim4  ,,theodorus3
 ,nay1 ,socrates1 not until we have     
finished what we are about2 for you     
truly said that we belong to a          
brotherhood which is free1 and are not  
the servants of the argument2 but the   
argument is our servant1 and must wait  
our leisure4 ,who is our judge8 ,or     
where is the spectator having any right 
to censure or control us1 as he might   
the poets8  ,,socrates3 ,then1 as this  
is your wish1 ,i will describe the      
leaders2 for there is no use in talking 
about the inferior sort4 ,in the first  
place1 the lords of philosophy have     
never1 from their youth upwards1 known  
their way to the ,agora1 or the         
dicastery1 or the council1 or any other 
political assembly2 they neither see nor
 hear the laws or decrees1 as they are  
called1 of the state written or recited2
 the eagerness of political societies in

 the attainment of offices--clubs1 and  
banquets1 and revels1 and               
singing-maidens1--do not enter even into
 their dreams4 ,whether any event has   
turned out well or ill in the city1 what
 disgrace may have descended to any one 
from his ancestors1 male or female1 are 
matters of which the philosopher no more
 knows than he can tell1 as they say1   
how many pints are contained in the     
ocean4 ,neither is he conscious of his  
ignorance4 ,for he does not hold aloof  
in order that he may gain a reputation2 
but the truth is1 that the outer form of
 him only is in the city3 his mind1     
disdaining the littlenesses and         
nothingnesses of human things1 is       
'flying all abroad' as ,pindar says1    
measuring earth and heaven and the      
things which are under and on the earth 
and above the heaven1 interrogating the 
whole nature of each and all in their   
entirety1 but not condescending to      
anything which is within reach4         
,,theodorus3 ,what do you mean1         

,socrates8  ,,socrates3 ,i will         
illustrate my meaning1 ,theodorus1 by   
the jest which the clever witty         
,thracian handmaid is said to have made 
about ,thales1 when he fell into a well 
as he was looking up at the stars4 ,she 
said1 that he was so eager to know what 
was going on in heaven1 that he could   
not see what was before his feet4 ,this 
is a jest which is equally applicable to
 all philosophers4 ,for the philosopher 
is wholly unacquainted with his         
next-door neighbour2 he is ignorant1 not
 only of what he is doing1 but he hardly
 knows whether he is a man or an animal2
 he is searching into the essence of    
man1 and busy in enquiring what belongs 
to such a nature to do or suffer        
different from any other2--,i think that
 you understand me1 ,theodorus8         
,,theodorus3 ,i do1 and what you say is 
true4  ,,socrates3 ,and thus1 my friend1
 on every occasion1 private as well as  
public1 as ,i said at first1 when he    
appears in a law-court1 or in any place 

in which he has to speak of things which
 are at his feet and before his eyes1 he
 is the jest1 not only of ,thracian     
handmaids but of the general herd1      
tumbling into wells and every sort of   
disaster through his inexperience4 ,his 
awkwardness is fearful1 and gives the   
impression of imbecility4 ,when he is   
reviled1 he has nothing personal to say 
in answer to the civilities of his      
adversaries1 for he knows no scandals of
 any one1 and they do not interest him2 
and therefore he is laughed at for his  
sheepishness2 and when others are being 
praised and glorified1 in the simplicity
 of his heart he cannot help going into 
fits of laughter1 so that he seems to be
 a downright idiot4 ,when he hears a    
tyrant or king eulogized1 he fancies    
that he is listening to the praises of  
some keeper of cattle--a swineherd1 or  
shepherd1 or perhaps a cowherd1 who is  
congratulated on the quantity of milk   
which he squeezes from them2 and he     
remarks that the creature whom they     

tend1 and out of whom they squeeze the  
wealth1 is of a less tractable and more 
insidious nature4 ,then1 again1 he      
observes that the great man is of       
necessity as ill-mannered and uneducated
 as any shepherd--for he has no leisure1
 and he is surrounded by a wall1 which  
is his mountain-pen4 ,hearing of        
enormous landed proprietors of ten      
thousand acres and more1 our philosopher
 deems this to be a trifle1 because he  
has been accustomed to think of the     
whole earth2 and when they sing the     
praises of family1 and say that some one
 is a gentleman because he can show     
seven generations of wealthy ancestors1 
he thinks that their sentiments only    
betray a dull and narrow vision in those
 who utter them1 and who are not        
educated enough to look at the whole1   
nor to consider that every man has had  
thousands and ten thousands of          
progenitors1 and among them have been   
rich and poor1 kings and slaves1        
,hellenes and barbarians1 innumerable4  

,and when people pride themselves on    
having a pedigree of twenty-five        
ancestors1 which goes back to ,heracles1
 the son of ,amphitryon1 he cannot      
understand their poverty of ideas4 ,why 
are they unable to calculate that       
,amphitryon had a twenty-fifth ancestor1
 who might have been anybody1 and was   
such as fortune made him1 and he had a  
fiftieth1 and so on8 ,he amuses himself 
with the notion that they cannot count1 
and thinks that a little arithmetic     
would have got rid of their senseless   
vanity4 ,now1 in all these cases our    
philosopher is derided by the vulgar1   
partly because he is thought to despise 
them1 and also because he is ignorant of
 what is before him1 and always at a    
loss4  ,,theodorus3 ,that is very true1 
,socrates4  ,,socrates3 ,but1 ,o my     
friend1 when he draws the other into    
upper air1 and gets him out of his pleas
 and rejoinders into the contemplation  
of justice and injustice in their own   
nature and in their difference from one 

another and from all other things2 or   
from the commonplaces about the         
happiness of a king or of a rich man to 
the consideration of government1 and of 
human happiness and misery in           
general--what they are1 and how a man is
 to attain the one and avoid the        
other--when that narrow1 keen1 little   
legal mind is called to account about   
all this1 he gives the philosopher his  
revenge2 for dizzied by the height at   
which he is hanging1 whence he looks    
down into space1 which is a strange     
experience to him1 he being dismayed1   
and lost1 and stammering broken words1  
is laughed at1 not by ,thracian         
handmaidens or any other uneducated     
persons1 for they have no eye for the   
situation1 but by every man who has not 
been brought up a slave4 ,such are the  
two characters1 ,theodorus3 the one of  
the freeman1 who has been trained in    
liberty and leisure1 whom you call the  
philosopher1--him we cannot blame       
because he appears simple and of no     

account when he has to perform some     
menial task1 such as packing up         
bed-clothes1 or flavouring a sauce or   
fawning speech2 the other character is  
that of the man who is able to do all   
this kind of service smartly and neatly1
 but knows not how to wear his cloak    
like a gentleman2 still less with the   
music of discourse can he hymn the true 
life aright which is lived by immortals 
or men blessed of heaven4  ,,theodorus3 
,if you could only persuade everybody1  
,socrates1 as you do me1 of the truth of
 your words1 there would be more peace  
and fewer evils among men4  ,,socrates3 
,evils1 ,theodorus1 can never pass away2
 for there must always remain something 
which is antagonistic to good4 ,having  
no place among the gods in heaven1 of   
necessity they hover around the mortal  
nature1 and this earthly sphere4        
,wherefore we ought to fly away from    
earth to heaven as quickly as we can2   
and to fly away is to become like ,god1 
as far as this is possible2 and to      

become like him1 is to become holy1     
just1 and wise4 ,but1 ,o my friend1 you 
cannot easily convince mankind that they
 should pursue virtue or avoid vice1 not
 merely in order that a man may seem to 
be good1 which is the reason given by   
the world1 and in my judgment is only a 
repetition of an old wives' fable4      
,whereas1 the truth is that ,god is     
never in any way unrighteous--he is     
perfect righteousness2 and he of us who 
is the most righteous is most like him4 
,herein is seen the true cleverness of a
 man1 and also his nothingness and want 
of manhood4 ,for to know this is true   
wisdom and virtue1 and ignorance of this
 is manifest folly and vice4 ,all other 
kinds of wisdom or cleverness1 which    
seem only1 such as the wisdom of        
politicians1 or the wisdom of the arts1 
are coarse and vulgar4 ,the unrighteous 
man1 or the sayer and doer of unholy    
things1 had far better not be encouraged
 in the illusion that his roguery is    
clever2 for men glory in their          

shame--they fancy that they hear others 
saying of them1 ',these are not mere    
good-for-nothing persons1 mere burdens  
of the earth1 but such as men should be 
who mean to dwell safely in a state4'   
,let us tell them that they are all the 
more truly what they do not think they  
are because they do not know it2 for    
they do not know the penalty of         
injustice1 which above all things they  
ought to know--not stripes and death1 as
 they suppose1 which evil-doers often   
escape1 but a penalty which cannot be   
escaped4  ,,theodorus3 ,what is that8   
,,socrates3 ,there are two patterns     
eternally set before them2 the one      
blessed and divine1 the other godless   
and wretched3 but they do not see them1 
or perceive that in their utter folly   
and infatuation they are growing like   
the one and unlike the other1 by reason 
of their evil deeds2 and the penalty is1
 that they lead a life answering to the 
pattern which they are growing like4    
,and if we tell them1 that unless they  

depart from their cunning1 the place of 
innocence will not receive them after   
death2 and that here on earth1 they will
 live ever in the likeness of their own 
evil selves1 and with evil friends--when
 they hear this they in their superior  
cunning will seem to be listening to the
 talk of idiots4  ,,theodorus3 ,very    
true1 ,socrates4  ,,socrates3 ,too true1
 my friend1 as ,i well know2 there is1  
however1 one peculiarity in their case3 
when they begin to reason in private    
about their dislike of philosophy1 if   
they have the courage to hear the       
argument out1 and do not run away1 they 
grow at last strangely discontented with
 themselves2 their rhetoric fades away1 
and they become helpless as children4   
,these however are digressions from     
which we must now desist1 or they will  
overflow1 and drown the original        
argument2 to which1 if you please1 we   
will now return4  ,,theodorus3 ,for my  
part1 ,socrates1 ,i would rather have   
the digressions1 for at my age ,i find  

them easier to follow2 but if you wish1 
let us go back to the argument4         
,,socrates3 ,had we not reached the     
point at which the partisans of the     
perpetual flux1 who say that things are 
as they seem to each one1 were          
confidently maintaining that the        
ordinances which the state commanded and
 thought just1 were just to the state   
which imposed them1 while they were in  
force2 this was especially asserted of  
justice2 but as to the good1 no one had 
any longer the hardihood to contend of  
any ordinances which the state thought  
and enacted to be good that these1 while
 they were in force1 were really        
good2--he who said so would be playing  
with the name 'good1' and would not     
touch the real question--it would be a  
mockery1 would it not8  ,,theodorus3    
,certainly it would4  ,,socrates3 ,he   
ought not to speak of the name1 but of  
the thing which is contemplated under   
the name4  ,,theodorus3 ,right4         
,,socrates3 ,whatever be the term used1 

the good or expedient is the aim of     
legislation1 and as far as she has an   
opinion1 the state imposes all laws with
 a view to the greatest expediency2 can 
legislation have any other aim8         
,,theodorus3 ,certainly not4            
,,socrates3 ,but is the aim attained    
always8 do not mistakes often happen8   
,,theodorus3 ,yes1 ,i think that there  
are mistakes4  ,,socrates3 ,the         
possibility of error will be more       
distinctly recognised1 if we put the    
question in reference to the whole class
 under which the good or expedient      
falls4 ,that whole class has to do with 
the future1 and laws are passed under   
the idea that they will be useful in    
after-time2 which1 in other words1 is   
the future4  ,,theodorus3 ,very true4   
,,socrates3 ,suppose now1 that we ask   
,protagoras1 or one of his disciples1 a 
question3--,o1 ,protagoras1 we will say 
to him1 ,man is1 as you declare1 the    
measure of all things--white1 heavy1    
light3 of all such things he is the     

judge2 for he has the criterion of them 
in himself1 and when he thinks that     
things are such as he experiences them  
to be1 he thinks what is and is true to 
himself4 ,is it not so8  ,,theodorus3   
,yes4  ,,socrates3 ,and do you extend   
your doctrine1 ,protagoras 7as we shall 
further say71 to the future as well as  
to the present2 and has he the criterion
 not only of what in his opinion is but 
of what will be1 and do things always   
happen to him as he expected8 ,for      
example1 take the case of heat3--,when  
an ordinary man thinks that he is going 
to have a fever1 and that this kind of  
heat is coming on1 and another person1  
who is a physician1 thinks the contrary1
 whose opinion is likely to prove right8
 ,or are they both right8--he will have 
a heat and fever in his own judgment1   
and not have a fever in the physician's 
judgment8  ,,theodorus3 ,how ludicrous6 
,,socrates3 ,and the vinegrower1 if ,i  
am not mistaken1 is a better judge of   
the sweetness or dryness of the vintage 

which is not yet gathered than the      
harp-player8  ,,theodorus3 ,certainly4  
,,socrates3 ,and in musical composition 
the musician will know better than the  
training master what the training master
 himself will hereafter think harmonious
 or the reverse8  ,,theodorus3 ,of      
course4  ,,socrates3 ,and the cook will 
be a better judge than the guest1 who is
 not a cook1 of the pleasure to be      
derived from the dinner which is in     
preparation2 for of present or past     
pleasure we are not as yet arguing2 but 
can we say that every one will be to    
himself the best judge of the pleasure  
which will seem to be and will be to him
 in the future8--nay1 would not you1    
,protagoras1 better guess which         
arguments in a court would convince any 
one of us than the ordinary man8        
,,theodorus3 ,certainly1 ,socrates1 he  
used to profess in the strongest manner 
that he was the superior of all men in  
this respect4  ,,socrates3 ,to be sure1 
friend3 who would have paid a large sum 

for the privilege of talking to him1 if 
he had really persuaded his visitors    
that neither a prophet nor any other man
 was better able to judge what will be  
and seem to be in the future than every 
one could for himself8  ,,theodorus3    
,who indeed8  ,,socrates3 ,and          
legislation and expediency are all      
concerned with the future2 and every one
 will admit that states1 in passing     
laws1 must often fail of their highest  
interests8  ,,theodorus3 ,quite true4   
,,socrates3 ,then we may fairly argue   
against your master1 that he must admit 
one man to be wiser than another1 and   
that the wiser is a measure3 but ,i1 who
 know nothing1 am not at all obliged to 
accept the honour which the advocate of 
,protagoras was just now forcing upon   
me1 whether ,i would or not1 of being a 
measure of anything4  ,,theodorus3 ,that
 is the best refutation of him1         
,socrates2 although he is also caught   
when he ascribes truth to the opinions  
of others1 who give the lie direct to   

his own opinion4  ,,socrates3 ,there are
 many ways1 ,theodorus1 in which the    
doctrine that every opinion of every man
 is true may be refuted2 but there is   
more difficulty in proving that states  
of feeling1 which are present to a man1 
and out of which arise sensations and   
opinions in accordance with them1 are   
also untrue4 ,and very likely ,i have   
been talking nonsense about them2 for   
they may be unassailable1 and those who 
say that there is clear evidence of     
them1 and that they are matters of      
knowledge1 may probably be right2 in    
which case our friend ,theaetetus was   
not so far from the mark when he        
identified perception and knowledge4    
,and therefore let us draw nearer1 as   
the advocate of ,protagoras desires2 and
 give the truth of the universal flux a 
ring3 is the theory sound or not8 at any
 rate1 no small war is raging about it1 
and there are combination not a few4    
,,theodorus3 ,no small1 war1 indeed1 for
 in ,ionia the sect makes rapid strides2

 the disciples of ,heracleitus are most 
energetic upholders of the doctrine4    
,,socrates3 ,then we are the more bound1
 my dear ,theodorus1 to examine the     
question from the foundation as it is   
set forth by themselves4  ,,theodorus3  
,certainly we are4 ,about these         
speculations of ,heracleitus1 which1 as 
you say1 are as old as ,homer1 or even  
older still1 the ,ephesians themselves1 
who profess to know them1 are downright 
mad1 and you cannot talk with them on   
the subject4 ,for1 in accordance with   
their text-books1 they are always in    
motion2 but as for dwelling upon an     
argument or a question1 and quietly     
asking and answering in turn1 they can  
no more do so than they can fly2 or     
rather1 the determination of these      
fellows not to have a particle of rest  
in them is more than the utmost powers  
of negation can express4 ,if you ask any
 of them a question1 he will produce1 as
 from a quiver1 sayings brief and dark1 
and shoot them at you2 and if you       

inquire the reason of what he has said1 
you will be hit by some other           
new-fangled word1 and will make no way  
with any of them1 nor they with one     
another2 their great care is1 not to    
allow of any settled principle either in
 their arguments or in their minds1     
conceiving1 as ,i imagine1 that any such
 principle would be stationary2 for they
 are at war with the stationary1 and do 
what they can to drive it out           
everywhere4  ,,socrates3 ,i suppose1    
,theodorus1 that you have only seen them
 when they were fighting1 and have never
 stayed with them in time of peace1 for 
they are no friends of yours2 and their 
peace doctrines are only communicated by
 them at leisure1 as ,i imagine1 to     
those disciples of theirs whom they want
 to make like themselves4  ,,theodorus3 
,disciples6 my good sir1 they have none2
 men of their sort are not one another's
 disciples1 but they grow up at their   
own sweet will1 and get their           
inspiration anywhere1 each of them      

saying of his neighbour that he knows   
nothing4 ,from these men1 then1 as ,i   
was going to remark1 you will never get 
a reason1 whether with their will or    
without their will2 we must take the    
question out of their hands1 and make   
the analysis ourselves1 as if we were   
doing geometrical problem4  ,,socrates3 
,quite right too2 but as touching the   
aforesaid problem1 have we not heard    
from the ancients1 who concealed their  
wisdom from the many in poetical        
figures1 that ,oceanus and ,tethys1 the 
origin of all things1 are streams1 and  
that nothing is at rest8 ,and now the   
moderns1 in their superior wisdom1 have 
declared the same openly1 that the      
cobbler too may hear and learn of them1 
and no longer foolishly imagine that    
some things are at rest and others in   
motion--having learned that all is      
motion1 he will duly honour his         
teachers4 ,i had almost forgotten the   
opposite doctrine1 ,theodorus1          
',alone ,being remains unmoved1 which is

 the name for the all4'  ,this is the   
language of ,parmenides1 ,melissus1 and 
their followers1 who stoutly maintain   
that all being is one and               
self-contained1 and has no place in     
which to move4 ,what shall we do1       
friend1 with all these people2 for1     
advancing step by step1 we have         
imperceptibly got between the           
combatants1 and1 unless we can protect  
our retreat1 we shall pay the penalty of
 our rashness--like the players in the  
palaestra who are caught upon the line1 
and are dragged different ways by the   
two parties4 ,therefore ,i think that we
 had better begin by considering those  
whom we first accosted1 'the            
river-gods1' and1 if we find any truth  
in them1 we will help them to pull us   
over1 and try to get away from the      
others4 ,but if the partisans of 'the   
whole' appear to speak more truly1 we   
will fly off from the party which would 
move the immovable1 to them4 ,and if ,i 
find that neither of them have anything 

reasonable to say1 we shall be in a     
ridiculous position1 having so great a  
conceit of our own poor opinion and     
rejecting that of ancient and famous    
men4 ,o ,theodorus1 do you think that   
there is any use in proceeding when the 
danger is so great8  ,,theodorus3 ,nay1 
,socrates1 not to examine thoroughly    
what the two parties have to say would  
be quite intolerable4  ,,socrates3 ,then
 examine we must1 since you1 who were so
 reluctant to begin1 are so eager to    
proceed4 ,the nature of motion appears  
to be the question with which we begin4 
,what do they mean when they say that   
all things are in motion8 ,is there only
 one kind of motion1 or1 as ,i rather   
incline to think1 two8 ,i should like to
 have your opinion upon this point in   
addition to my own1 that ,i may err1 if 
,i must err1 in your company2 tell me1  
then1 when a thing changes from one     
place to another1 or goes round in the  
same place1 is not that what is called  
motion8  ,,theodorus3 ,yes4  ,,socrates3

 ,here then we have one kind of motion4 
,but when a thing1 remaining on the same
 spot1 grows old1 or becomes black from 
being white1 or hard from being soft1 or
 undergoes any other change1 may not    
this be properly called motion of       
another kind8  ,,theodorus3 ,i think so4
  ,,socrates3 ,say rather that it must  
be so4 ,of motion then there are these  
two kinds1 'change1' and 'motion in     
place4'  ,,theodorus3 ,you are right4   
,,socrates3 ,and now1 having made this  
distinction1 let us address ourselves to
 those who say that all is motion1 and  
ask them whether all things according to
 them have the two kinds of motion1 and 
are changed as well as move in place1 or
 is one thing moved in both ways1 and   
another in one only8  ,,theodorus3      
,indeed1 ,i do not know what to answer2 
but ,i think they would say that all    
things are moved in both ways4          
,,socrates3 ,yes1 comrade2 for1 if not1 
they would have to say that the same    
things are in motion and at rest1 and   

there would be no more truth in saying  
that all things are in motion1 than that
 all things are at rest4  ,,theodorus3  
,to be sure4  ,,socrates3 ,and if they  
are to be in motion1 and nothing is to  
be devoid of motion1 all things must    
always have every sort of motion8       
,,theodorus3 ,most true4  ,,socrates3   
,consider a further point3 did we not   
understand them to explain the          
generation of heat1 whiteness1 or       
anything else1 in some such manner as   
the following3--were they not saying    
that each of them is moving between the 
agent and the patient1 together with a  
perception1 and that the patient ceases 
to be a perceiving power and becomes a  
percipient1 and the agent a quale       
instead of a quality8 ,i suspect that   
quality may appear a strange and uncouth
 term to you1 and that you do not       
understand the abstract expression4     
,then ,i will take concrete instances3  
,i mean to say that the producing power 
or agent becomes neither heat nor       

whiteness but hot and white1 and the    
like of other things4 ,for ,i must      
repeat what ,i said before1 that neither
 the agent nor patient have any absolute
 existence1 but when they come together 
and generate sensations and their       
objects1 the one becomes a thing of a   
certain quality1 and the other a        
percipient4 ,you remember8  ,,theodorus3
 ,of course4  ,,socrates3 ,we may leave 
the details of their theory unexamined1 
but we must not forget to ask them the  
only question with which we are         
concerned3 ,are all things in motion and
 flux8  ,,theodorus3 ,yes1 they will    
reply4  ,,socrates3 ,and they are moved 
in both those ways which we             
distinguished1 that is to say1 they move
 in place and are also changed8         
,,theodorus3 ,of course1 if the motion  
is to be perfect4  ,,socrates3 ,if they 
only moved in place and were not        
changed1 we should be able to say what  
is the nature of the things which are in
 motion and flux8  ,,theodorus3         

,exactly4  ,,socrates3 ,but now1 since  
not even white continues to flow white1 
and whiteness itself is a flux or change
 which is passing into another colour1  
and is never to be caught standing      
still1 can the name of any colour be    
rightly used at all8  ,,theodorus3 ,how 
is that possible1 ,socrates1 either in  
the case of this or of any other        
quality--if while we are using the word 
the object is escaping in the flux8     
,,socrates3 ,and what would you say of  
perceptions1 such as sight and hearing1 
or any other kind of perception8 ,is    
there any stopping in the act of seeing 
and hearing8  ,,theodorus3 ,certainly   
not1 if all things are in motion4       
,,socrates3 ,then we must not speak of  
seeing any more than of not-seeing1 nor 
of any other perception more than of any
 non-perception1 if all things partake  
of every kind of motion8  ,,theodorus3  
,certainly not4  ,,socrates3 ,yet       
perception is knowledge3 so at least    
,theaetetus and ,i were saying4         

,,theodorus3 ,very true4  ,,socrates3   
,then when we were asked what is        
knowledge1 we no more answered what is  
knowledge than what is not knowledge8   
,,theodorus3 ,i suppose not4            
,,socrates3 ,here1 then1 is a fine      
result3 we corrected our first answer in
 our eagerness to prove that nothing is 
at rest4 ,but if nothing is at rest1    
every answer upon whatever subject is   
equally right3 you may say that a thing 
is or is not thus2 or1 if you prefer1   
'becomes' thus2 and if we say 'becomes1'
 we shall not then hamper them with     
words expressive of rest4  ,,theodorus3 
,quite true4  ,,socrates3 ,yes1         
,theodorus1 except in saying 'thus' and 
'not thus4' ,but you ought not to use   
the word 'thus1' for there is no motion 
in 'thus' or in 'not thus4' ,the        
maintainers of the doctrine have as yet 
no words in which to express themselves1
 and must get a new language4 ,i know of
 no word that will suit them1 except    
perhaps 'no how1' which is perfectly    

indefinite4  ,,theodorus3 ,yes1 that is 
a manner of speaking in which they will 
be quite at home4  ,,socrates3 ,and so1 
,theodorus1 we have got rid of your     
friend without assenting to his         
doctrine1 that every man is the measure 
of all things--a wise man only is a     
measure2 neither can we allow that      
knowledge is perception1 certainly not  
on the hypothesis of a perpetual flux1  
unless perchance our friend ,theaetetus 
is able to convince us that it is4      
,,theodorus3 ,very good1 ,socrates2 and 
now that the argument about the doctrine
 of ,protagoras has been completed1 ,i  
am absolved from answering2 for this was
 the agreement4  ,,theaetetus3 ,not1    
,theodorus1 until you and ,socrates have
 discussed the doctrine of those who say
 that all things are at rest1 as you    
were proposing4  ,,theodorus3 ,you1     
,theaetetus1 who are a young rogue1 must
 not instigate your elders to a breach  
of faith1 but should prepare to answer  
,socrates in the remainder of the       

argument4  ,,theaetetus3 ,yes1 if he    
wishes2 but ,i would rather have heard  
about the doctrine of rest4             
,,theodorus3 ,invite ,socrates to an    
argument--invite horsemen to the open   
plain2 do but ask him1 and he will      
answer4  ,,socrates3 ,nevertheless1     
,theodorus1 ,i am afraid that ,i shall  
not be able to comply with the request  
of ,theaetetus4  ,,theodorus3 ,not      
comply6 for what reason8  ,,socrates3   
,my reason is that ,i have a kind of    
reverence2 not so much for ,melissus and
 the others1 who say that ',all is one  
and at rest1' as for the great leader   
himself1 ,parmenides1 venerable and     
awful1 as in ,homeric language he may be
 called2--him ,i should be ashamed to   
approach in a spirit unworthy of him4 ,i
 met him when he was an old man1 and ,i 
was a mere youth1 and he appeared to me 
to have a glorious depth of mind4 ,and  
,i am afraid that we may not understand 
his words1 and may be still further from
 understanding his meaning2 above all ,i

 fear that the nature of knowledge1     
which is the main subject of our        
discussion1 may be thrust out of sight  
by the unbidden guests who will come    
pouring in upon our feast of discourse1 
if we let them in--besides1 the question
 which is now stirring is of immense    
extent1 and will be treated unfairly if 
only considered by the way2 or if       
treated adequately and at length1 will  
put into the shade the other question of
 knowledge4 ,neither the one nor the    
other can be allowed2 but ,i must try by
 my art of midwifery to deliver         
,theaetetus of his conceptions about    
knowledge4  ,,theaetetus3 ,very well2 do
 so if you will4  ,,socrates3 ,then now1
 ,theaetetus1 take another view of the  
subject3 you answered that knowledge is 
perception8  ,,theaetetus3 ,i did4      
,,socrates3 ,and if any one were to ask 
you3 ,with what does a man see black and
 white colours8 and with what does he   
hear high and low sounds8--you would    
say1 if ,i am not mistaken1 ',with the  

eyes and with the ears4'  ,,theaetetus3 
,i should4  ,,socrates3 ,the free use of
 words and phrases1 rather than minute  
precision1 is generally characteristic  
of a liberal education1 and the opposite
 is pedantic2 but sometimes precision is
 necessary1 and ,i believe that the     
answer which you have just given is open
 to the charge of incorrectness2 for    
which is more correct1 to say that we   
see or hear with the eyes and with the  
ears1 or through the eyes and through   
the ears4  ,,theaetetus3 ,i should say  
'through1' ,socrates1 rather than       
'with4'  ,,socrates3 ,yes1 my boy1 for  
no one can suppose that in each of us1  
as in a sort of ,trojan horse1 there are
 perched a number of unconnected senses1
 which do not all meet in some one      
nature1 the mind1 or whatever we please 
to call it1 of which they are the       
instruments1 and with which through them
 we perceive objects of sense4          
,,theaetetus3 ,i agree with you in that 
opinion4  ,,socrates3 ,the reason why ,i

 am thus precise is1 because ,i want to 
know whether1 when we perceive black and
 white through the eyes1 and again1     
other qualities through other organs1 we
 do not perceive them with one and the  
same part of ourselves1 and1 if you were
 asked1 you might refer all such        
perceptions to the body4 ,perhaps1      
however1 ,i had better allow you to     
answer for yourself and not interfere4  
,tell me1 then1 are not the organs      
through which you perceive warm and hard
 and light and sweet1 organs of the     
body8  ,,theaetetus3 ,of the body1      
certainly4  ,,socrates3 ,and you would  
admit that what you perceive through one
 faculty you cannot perceive through    
another2 the objects of hearing1 for    
example1 cannot be perceived through    
sight1 or the objects of sight through  
hearing8  ,,theaetetus3 ,of course not4 
,,socrates3 ,if you have any thought    
about both of them1 this common         
perception cannot come to you1 either   
through the one or the other organ8     

,,theaetetus3 ,it cannot4  ,,socrates3  
,how about sounds and colours3 in the   
first place you would admit that they   
both exist8  ,,theaetetus3 ,yes4        
,,socrates3 ,and that either of them is 
different from the other1 and the same  
with itself8  ,,theaetetus3 ,certainly4 
,,socrates3 ,and that both are two and  
each of them one8  ,,theaetetus3 ,yes4  
,,socrates3 ,you can further observe    
whether they are like or unlike one     
another8  ,,theaetetus3 ,i dare say4    
,,socrates3 ,but through what do you    
perceive all this about them8 for       
neither through hearing nor yet through 
seeing can you apprehend that which they
 have in common4 ,let me give you an    
illustration of the point at issue3--,if
 there were any meaning in asking       
whether sounds and colours are saline or
 not1 you would be able to tell me what 
faculty would consider the question4 ,it
 would not be sight or hearing1 but some
 other4  ,,theaetetus3 ,certainly2 the  
faculty of taste4  ,,socrates3 ,very    

good2 and now tell me what is the power 
which discerns1 not only in sensible    
objects1 but in all things1 universal   
notions1 such as those which are called 
being and not-being1 and those others   
about which we were just asking--what   
organs will you assign for the          
perception of these notions8            
,,theaetetus3 ,you are thinking of being
 and not being1 likeness and unlikeness1
 sameness and difference1 and also of   
unity and other numbers which are       
applied to objects of sense2 and you    
mean to ask1 through what bodily organ  
the soul perceives odd and even numbers 
and other arithmetical conceptions4     
,,socrates3 ,you follow me excellently1 
,theaetetus2 that is precisely what ,i  
am asking4  ,,theaetetus3 ,indeed1      
,socrates1 ,i cannot answer2 my only    
notion is1 that these1 unlike objects of
 sense1 have no separate organ1 but that
 the mind1 by a power of her own1       
contemplates the universals in all      
things4  ,,socrates3 ,you are a beauty1 

,theaetetus1 and not ugly1 as ,theodorus
 was saying2 for he who utters the      
beautiful is himself beautiful and good4
 ,and besides being beautiful1 you have 
done me a kindness in releasing me from 
a very long discussion1 if you are clear
 that the soul views some things by     
herself and others through the bodily   
organs4 ,for that was my own opinion1   
and ,i wanted you to agree with me4     
,,theaetetus3 ,i am quite clear4        
,,socrates3 ,and to which class would   
you refer being or essence2 for this1 of
 all our notions1 is the most universal8
  ,,theaetetus3 ,i should say1 to that  
class which the soul aspires to know of 
herself4  ,,socrates3 ,and would you say
 this also of like and unlike1 same and 
other8  ,,theaetetus3 ,yes4  ,,socrates3
 ,and would you say the same of the     
noble and base1 and of good and evil8   
,,theaetetus3 ,these ,i conceive to be  
notions which are essentially relative1 
and which the soul also perceives by    
comparing in herself things past and    

present with the future4  ,,socrates3   
,and does she not perceive the hardness 
of that which is hard by the touch1 and 
the softness of that which is soft      
equally by the touch8  ,,theaetetus3    
,yes4  ,,socrates3 ,but their essence   
and what they are1 and their opposition 
to one another1 and the essential nature
 of this opposition1 the soul herself   
endeavours to decide for us by the      
review and comparison of them8          
,,theaetetus3 ,certainly4  ,,socrates3  
,the simple sensations which reach the  
soul through the body are given at birth
 to men and animals by nature1 but their
 reflections on the being and use of    
them are slowly and hardly gained1 if   
they are ever gained1 by education and  
long experience4  ,,theaetetus3         
,assuredly4  ,,socrates3 ,and can a man 
attain truth who fails of attaining     
being8  ,,theaetetus3 ,impossible4      
,,socrates3 ,and can he who misses the  
truth of anything1 have a knowledge of  
that thing8  ,,theaetetus3 ,he cannot4  

,,socrates3 ,then knowledge does not    
consist in impressions of sense1 but in 
reasoning about them2 in that only1 and 
not in the mere impression1 truth and   
being can be attained8  ,,theaetetus3   
,clearly4  ,,socrates3 ,and would you   
call the two processes by the same name1
 when there is so great a difference    
between them8  ,,theaetetus3 ,that would
 certainly not be right4  ,,socrates3   
,and what name would you give to seeing1
 hearing1 smelling1 being cold and being
 hot8  ,,theaetetus3 ,i should call all 
of them perceiving--what other name     
could be given to them8  ,,socrates3    
,perception would be the collective name
 of them8  ,,theaetetus3 ,certainly4    
,,socrates3 ,which1 as we say1 has no   
part in the attainment of truth any more
 than of being8  ,,theaetetus3          
,certainly not4  ,,socrates3 ,and       
therefore not in science or knowledge8  
,,theaetetus3 ,no4  ,,socrates3 ,then   
perception1 ,theaetetus1 can never be   
the same as knowledge or science8       

,,theaetetus3 ,clearly not1 ,socrates2  
and knowledge has now been most         
distinctly proved to be different from  
perception4  ,,socrates3 ,but the       
original aim of our discussion was to   
find out rather what knowledge is than  
what it is not2 at the same time we have
 made some progress1 for we no longer   
seek for knowledge in perception at all1
 but in that other process1 however     
called1 in which the mind is alone and  
engaged with being4  ,,theaetetus3 ,you 
mean1 ,socrates1 if ,i am not mistaken1 
what is called thinking or opining4     
,,socrates3 ,you conceive truly4 ,and   
now1 my friend1 please to begin again at
 this point2 and having wiped out of    
your memory all that has preceded1 see  
if you have arrived at any clearer view1
 and once more say what is knowledge4   
,,theaetetus3 ,i cannot say1 ,socrates1 
that all opinion is knowledge1 because  
there may be a false opinion2 but ,i    
will venture to assert1 that knowledge  
is true opinion3 let this then be my    

reply2 and if this is hereafter         
disproved1 ,i must try to find another4 
,,socrates3 ,that is the way in which   
you ought to answer1 ,theaetetus1 and   
not in your former hesitating strain1   
for if we are bold we shall gain one of 
two advantages2 either we shall find    
what we seek1 or we shall be less likely
 to think that we know what we do not   
know--in either case we shall be richly 
rewarded4 ,and now1 what are you        
saying8--,are there two sorts of        
opinion1 one true and the other false2  
and do you define knowledge to be the   
true8  ,,theaetetus3 ,yes1 according to 
my present view4  ,,socrates3 ,is it    
still worth our while to resume the     
discussion touching opinion8            
,,theaetetus3 ,to what are you alluding8
  ,,socrates3 ,there is a point which   
often troubles me1 and is a great       
perplexity to me1 both in regard to     
myself and others4 ,i cannot make out   
the nature or origin of the mental      
experience to which ,i refer4           

,,theaetetus3 ,pray what is it8         
,,socrates3 ,how there can be false     
opinion--that difficulty still troubles 
the eye of my mind2 and ,i am uncertain 
whether ,i shall leave the question1 or 
begin over again in a new way4          
,,theaetetus3 ,begin again1             
,socrates1--at least if you think that  
there is the slightest necessity for    
doing so4 ,were not you and ,theodorus  
just now remarking very truly1 that in  
discussions of this kind we may take our
 own time8  ,,socrates3 ,you are quite  
right1 and perhaps there will be no harm
 in retracing our steps and beginning   
again4 ,better a little which is well   
done1 than a great deal imperfectly4    
,,theaetetus3 ,certainly4  ,,socrates3  
,well1 and what is the difficulty8 ,do  
we not speak of false opinion1 and say  
that one man holds a false and another a
 true opinion1 as though there were some
 natural distinction between them8      
,,theaetetus3 ,we certainly say so4     
,,socrates3 ,all things and everything  

are either known or not known4 ,i leave 
out of view the intermediate conceptions
 of learning and forgetting1 because    
they have nothing to do with our present
 question4  ,,theaetetus3 ,there can be 
no doubt1 ,socrates1 if you exclude     
these1 that there is no other           
alternative but knowing or not knowing a
 thing4  ,,socrates3 ,that point being  
now determined1 must we not say that he 
who has an opinion1 must have an opinion
 about something which he knows or does 
not know8  ,,theaetetus3 ,he must4      
,,socrates3 ,he who knows1 cannot but   
know2 and he who does not know1 cannot  
know8  ,,theaetetus3 ,of course4        
,,socrates3 ,what shall we say then8    
,when a man has a false opinion does he 
think that which he knows to be some    
other thing which he knows1 and knowing 
both1 is he at the same time ignorant of
 both8  ,,theaetetus3 ,that1 ,socrates1 
is impossible4  ,,socrates3 ,but perhaps
 he thinks of something which he does   
not know as some other thing which he   

does not know2 for example1 he knows    
neither ,theaetetus nor ,socrates1 and  
yet he fancies that ,theaetetus is      
,socrates1 or ,socrates ,theaetetus8    
,,theaetetus3 ,how can he8  ,,socrates3 
,but surely he cannot suppose what he   
knows to be what he does not know1 or   
what he does not know to be what he     
knows8  ,,theaetetus3 ,that would be    
monstrous4  ,,socrates3 ,where1 then1 is
 false opinion8 ,for if all things are  
either known or unknown1 there can be no
 opinion which is not comprehended under
 this alternative1 and so false opinion 
is excluded4  ,,theaetetus3 ,most true4 
,,socrates3 ,suppose that we remove the 
question out of the sphere of knowing or
 not knowing1 into that of being and    
not-being4  ,,theaetetus3 ,what do you  
mean8  ,,socrates3 ,may we not suspect  
the simple truth to be that he who      
thinks about anything1 that which is    
not1 will necessarily think what is     
false1 whatever in other respects may be
 the state of his mind8  ,,theaetetus3  

,that1 again1 is not unlikely1          
,socrates4  ,,socrates3 ,then suppose   
some one to say to us1 ,theaetetus3--,is
 it possible for any man to think that  
which is not1 either as a self-existent 
substance or as a predicate of something
 else8 ,and suppose that we answer1     
',yes1 he can1 when he thinks what is   
not true4'--,that will be our answer8   
,,theaetetus3 ,yes4  ,,socrates3 ,but is
 there any parallel to this8            
,,theaetetus3 ,what do you mean8        
,,socrates3 ,can a man see something and
 yet see nothing8  ,,theaetetus3        
,impossible4  ,,socrates3 ,but if he    
sees any one thing1 he sees something   
that exists4 ,do you suppose that what  
is one is ever to be found among        
non-existing things8  ,,theaetetus3 ,i  
do not4  ,,socrates3 ,he then who sees  
some one thing1 sees something which is8
  ,,theaetetus3 ,clearly4  ,,socrates3  
,and he who hears anything1 hears some  
one thing1 and hears that which is8     
,,theaetetus3 ,yes4  ,,socrates3 ,and he

 who touches anything1 touches something
 which is one and therefore is8         
,,theaetetus3 ,that again is true4      
,,socrates3 ,and does not he who thinks1
 think some one thing8  ,,theaetetus3   
,certainly4  ,,socrates3 ,and does not  
he who thinks some one thing1 think     
something which is8  ,,theaetetus3 ,i   
agree4  ,,socrates3 ,then he who thinks 
of that which is not1 thinks of nothing8
  ,,theaetetus3 ,clearly4  ,,socrates3  
,and he who thinks of nothing1 does not 
think at all8  ,,theaetetus3 ,obviously4
  ,,socrates3 ,then no one can think    
that which is not1 either as a          
self-existent substance or as a         
predicate of something else8            
,,theaetetus3 ,clearly not4  ,,socrates3
 ,then to think falsely is different    
from thinking that which is not8        
,,theaetetus3 ,it would seem so4        
,,socrates3 ,then false opinion has no  
existence in us1 either in the sphere of
 being or of knowledge8  ,,theaetetus3  
,certainly not4  ,,socrates3 ,but may   

not the following be the description of 
what we express by this name8           
,,theaetetus3 ,what8  ,,socrates3 ,may  
we not suppose that false opinion or    
thought is a sort of heterodoxy2 a      
person may make an exchange in his mind1
 and say that one real object is another
 real object4 ,for thus he always thinks
 that which is1 but he puts one thing in
 place of another2 and missing the aim  
of his thoughts1 he may be truly said to
 have false opinion4  ,,theaetetus3 ,now
 you appear to me to have spoken the    
exact truth3 when a man puts the base in
 the place of the noble1 or the noble in
 the place of the base1 then he has     
truly false opinion4  ,,socrates3 ,i    
see1 ,theaetetus1 that your fear has    
disappeared1 and that you are beginning 
to despise me4  ,,theaetetus3 ,what     
makes you say so8  ,,socrates3 ,you     
think1 if ,i am not mistaken1 that your 
'truly false' is safe from censure1 and 
that ,i shall never ask whether there   
can be a swift which is slow1 or a heavy

 which is light1 or any other           
self-contradictory thing1 which works1  
not according to its own nature1 but    
according to that of its opposite4 ,but 
,i will not insist upon this1 for ,i do 
not wish needlessly to discourage you4  
,and so you are satisfied that false    
opinion is heterodoxy1 or the thought of
 something else8  ,,theaetetus3 ,i am4  
,,socrates3 ,it is possible then upon   
your view for the mind to conceive of   
one thing as another8  ,,theaetetus3    
,true4  ,,socrates3 ,but must not the   
mind1 or thinking power1 which misplaces
 them1 have a conception either of both 
objects or of one of them8              
,,theaetetus3 ,certainly4  ,,socrates3  
,either together or in succession8      
,,theaetetus3 ,very good4  ,,socrates3  
,and do you mean by conceiving1 the same
 which ,i mean8  ,,theaetetus3 ,what is 
that8  ,,socrates3 ,i mean the          
conversation which the soul holds with  
herself in considering of anything4 ,i  
speak of what ,i scarcely understand2   

but the soul when thinking appears to me
 to be just talking--asking questions of
 herself and answering them1 affirming  
and denying4 ,and when she has arrived  
at a decision1 either gradually or by a 
sudden impulse1 and has at last agreed1 
and does not doubt1 this is called her  
opinion4 ,i say1 then1 that to form an  
opinion is to speak1 and opinion is a   
word spoken1--,i mean1 to oneself and in
 silence1 not aloud or to another3 ,what
 think you8  ,,theaetetus3 ,i agree4    
,,socrates3 ,then when any one thinks of
 one thing as another1 he is saying to  
himself that one thing is another8      
,,theaetetus3 ,yes4  ,,socrates3 ,but do
 you ever remember saying to yourself   
that the noble is certainly base1 or the
 unjust just2 or1 best of all--have you 
ever attempted to convince yourself that
 one thing is another8 ,nay1 not even in
 sleep1 did you ever venture to say to  
yourself that odd is even1 or anything  
of the kind8  ,,theaetetus3 ,never4     
,,socrates3 ,and do you suppose that any

 other man1 either in his senses or out 
of them1 ever seriously tried to        
persuade himself that an ox is a horse1 
or that two are one8  ,,theaetetus3     
,certainly not4  ,,socrates3 ,but if    
thinking is talking to oneself1 no one  
speaking and thinking of two objects1   
and apprehending them both in his soul1 
will say and think that the one is the  
other of them1 and ,i must add1 that    
even you1 lover of dispute as you are1  
had better let the word 'other' alone   
7i4e4 not insist that 'one' and 'other' 
are the same 7,both words in ,greek are 
called eteron3 compare ,parmen42        
,euthyd4774 ,i mean to say1 that no one 
thinks the noble to be base1 or anything
 of the kind4  ,,theaetetus3 ,i will    
give up the word 'other1' ,socrates2 and
 ,i agree to what you say4  ,,socrates3 
,if a man has both of them in his       
thoughts1 he cannot think that the one  
of them is the other8  ,,theaetetus3    
,true4  ,,socrates3 ,neither1 if he has 
one of them only in his mind and not the

 other1 can he think that one is the    
other8  ,,theaetetus3 ,true2 for we     
should have to suppose that he          
apprehends that which is not in his     
thoughts at all4  ,,socrates3 ,then no  
one who has either both or only one of  
the two objects in his mind can think   
that the one is the other4 ,and         
therefore1 he who maintains that false  
opinion is heterodoxy is talking        
nonsense2 for neither in this1 any more 
than in the previous way1 can false     
opinion exist in us4  ,,theaetetus3 ,no4
  ,,socrates3 ,but if1 ,theaetetus1 this
 is not admitted1 we shall be driven    
into many absurdities4  ,,theaetetus3   
,what are they8  ,,socrates3 ,i will not
 tell you until ,i have endeavoured to  
consider the matter from every point of 
view4 ,for ,i should be ashamed of us if
 we were driven in our perplexity to    
admit the absurd consequences of which  
,i speak4 ,but if we find the solution1 
and get away from them1 we may regard   
them only as the difficulties of others1

 and the ridicule will not attach to us4
 ,on the other hand1 if we utterly fail1
 ,i suppose that we must be humble1 and 
allow the argument to trample us under  
foot1 as the sea-sick passenger is      
trampled upon by the sailor1 and to do  
anything to us4 ,listen1 then1 while ,i 
tell you how ,i hope to find a way out  
of our difficulty4  ,,theaetetus3 ,let  
me hear4  ,,socrates3 ,i think that we  
were wrong in denying that a man could  
think what he knew to be what he did not
 know2 and that there is a way in which 
such a deception is possible4           
,,theaetetus3 ,you mean to say1 as ,i   
suspected at the time1 that ,i may know 
,socrates1 and at a distance see some   
one who is unknown to me1 and whom ,i   
mistake for him--then the deception will
 occur8  ,,socrates3 ,but has not that  
position been relinquished by us1       
because involving the absurdity that we 
should know and not know the things     
which we know8  ,,theaetetus3 ,true4    
,,socrates3 ,let us make the assertion  

in another form1 which may or may not   
have a favourable issue2 but as we are  
in a great strait1 every argument should
 be turned over and tested4 ,tell me1   
then1 whether ,i am right in saying that
 you may learn a thing which at one time
 you did not know8  ,,theaetetus3       
,certainly you may4  ,,socrates3 ,and   
another and another8  ,,theaetetus3     
,yes4  ,,socrates3 ,i would have you    
imagine1 then1 that there exists in the 
mind of man a block of wax1 which is of 
different sizes in different men2       
harder1 moister1 and having more or less
 of purity in one than another1 and in  
some of an intermediate quality4        
,,theaetetus3 ,i see4  ,,socrates3 ,let 
us say that this tablet is a gift of    
,memory1 the mother of the ,muses2 and  
that when we wish to remember anything  
which we have seen1 or heard1 or thought
 in our own minds1 we hold the wax to   
the perceptions and thoughts1 and in    
that material receive the impression of 
them as from the seal of a ring2 and    

that we remember and know what is       
imprinted as long as the image lasts2   
but when the image is effaced1 or cannot
 be taken1 then we forget and do not    
know4  ,,theaetetus3 ,very good4        
,,socrates3 ,now1 when a person has this
 knowledge1 and is considering something
 which he sees or hears1 may not false  
opinion arise in the following manner8  
,,theaetetus3 ,in what manner8          
,,socrates3 ,when he thinks what he     
knows1 sometimes to be what he knows1   
and sometimes to be what he does not    
know4 ,we were wrong before in denying  
the possibility of this4  ,,theaetetus3 
,and how would you amend the former     
statement8  ,,socrates3 ,i should begin 
by making a list of the impossible cases
 which must be excluded4 7#a7 ,no one   
can think one thing to be another when  
he does not perceive either of them1 but
 has the memorial or seal of both of    
them in his mind2 nor can any mistaking 
of one thing for another occur1 when he 
only knows one1 and does not know1 and  

has no impression of the other2 nor can 
he think that one thing which he does   
not know is another thing which he does 
not know1 or that what he does not know 
is what he knows2 nor 7#b7 that one     
thing which he perceives is another     
thing which he perceives1 or that       
something which he perceives is         
something which he does not perceive2 or
 that something which he does not       
perceive is something else which he does
 not perceive2 or that something which  
he does not perceive is something which 
he perceives2 nor again 7#c7 can he     
think that something which he knows and 
perceives1 and of which he has the      
impression coinciding with sense1 is    
something else which he knows and       
perceives1 and of which he has the      
impression coinciding with sense2--this 
last case1 if possible1 is still more   
inconceivable than the others2 nor 7#d7 
can he think that something which he    
knows and perceives1 and of which he has
 the memorial coinciding with sense1 is 

something else which he knows2 nor so   
long as these agree1 can he think that a
 thing which he knows and perceives is  
another thing which he perceives2 or    
that a thing which he does not know and 
does not perceive1 is the same as       
another thing which he does not know and
 does not perceive2--nor again1 can he  
suppose that a thing which he does not  
know and does not perceive is the same  
as another thing which he does not know2
 or that a thing which he does not know 
and does not perceive is another thing  
which he does not perceive3--,all these 
utterly and absolutely exclude the      
possibility of false opinion4 ,the only 
cases1 if any1 which remain1 are the    
following4  ,,theaetetus3 ,what are     
they8 ,if you tell me1 ,i may perhaps   
understand you better2 but at present ,i
 am unable to follow you4  ,,socrates3  
,a person may think that some things    
which he knows1 or which he perceives   
and does not know1 are some other things
 which he knows and perceives2 or that  

some things which he knows and          
perceives1 are other things which he    
knows and perceives4  ,,theaetetus3 ,i  
understand you less than ever now4      
,,socrates3 ,hear me once more1         
then3--,i1 knowing ,theodorus1 and      
remembering in my own mind what sort of 
person he is1 and also what sort of     
person ,theaetetus is1 at one time see  
them1 and at another time do not see    
them1 and sometimes ,i touch them1 and  
at another time not1 or at one time ,i  
may hear them or perceive them in some  
other way1 and at another time not      
perceive them1 but still ,i remember    
them1 and know them in my own mind4     
,,theaetetus3 ,very true4  ,,socrates3  
,then1 first of all1 ,i want you to     
understand that a man may or may not    
perceive sensibly that which he knows4  
,,theaetetus3 ,true4  ,,socrates3 ,and  
that which he does not know will        
sometimes not be perceived by him and   
sometimes will be perceived and only    
perceived8  ,,theaetetus3 ,that is also 

true4  ,,socrates3 ,see whether you can 
follow me better now3 ,socrates can     
recognize ,theodorus and ,theaetetus1   
but he sees neither of them1 nor does he
 perceive them in any other way2 he     
cannot then by any possibility imagine  
in his own mind that ,theaetetus is     
,theodorus4 ,am ,i not right8           
,,theaetetus3 ,you are quite right4     
,,socrates3 ,then that was the first    
case of which ,i spoke4  ,,theaetetus3  
,yes4  ,,socrates3 ,the second case was1
 that ,i1 knowing one of you and not    
knowing the other1 and perceiving       
neither1 can never think him whom ,i    
know to be him whom ,i do not know4     
,,theaetetus3 ,true4  ,,socrates3 ,in   
the third case1 not knowing and not     
perceiving either of you1 ,i cannot     
think that one of you whom ,i do not    
know is the other whom ,i do not know4  
,i need not again go over the catalogue 
of excluded cases1 in which ,i cannot   
form a false opinion about you and      
,theodorus1 either when ,i know both or 

when ,i am in ignorance of both1 or when
 ,i know one and not the other4 ,and the
 same of perceiving3 do you understand  
me8  ,,theaetetus3 ,i do4  ,,socrates3  
,the only possibility of erroneous      
opinion is1 when knowing you and        
,theodorus1 and having on the waxen     
block the impression of both of you     
given as by a seal1 but seeing you      
imperfectly and at a distance1 ,i try to
 assign the right impression of memory  
to the right visual impression1 and to  
fit this into its own print3 if ,i      
succeed1 recognition will take place2   
but if ,i fail and transpose them1      
putting the foot into the wrong         
shoe--that is to say1 putting the vision
 of either of you on to the wrong       
impression1 or if my mind1 like the     
sight in a mirror1 which is transferred 
from right to left1 err by reason of    
some similar affection1 then            
'heterodoxy' and false opinion ensues4  
,,theaetetus3 ,yes1 ,socrates1 you have 
described the nature of opinion with    

wonderful exactness4  ,,socrates3 ,or   
again1 when ,i know both of you1 and    
perceive as well as know one of you1 but
 not the other1 and my knowledge of him 
does not accord with perception--that   
was the case put by me just now which   
you did not understand4  ,,theaetetus3  
,no1 ,i did not4  ,,socrates3 ,i meant  
to say1 that when a person knows and    
perceives one of you1 his knowledge     
coincides with his perception1 he will  
never think him to be some other person1
 whom he knows and perceives1 and the   
knowledge of whom coincides with his    
perception--for that also was a case    
supposed4  ,,theaetetus3 ,true4         
,,socrates3 ,but there was an omission  
of the further case1 in which1 as we now
 say1 false opinion may arise1 when     
knowing both1 and seeing1 or having some
 other sensible perception of both1 ,i  
fail in holding the seal over against   
the corresponding sensation2 like a bad 
archer1 ,i miss and fall wide of the    
mark--and this is called falsehood4     

,,theaetetus3 ,yes2 it is rightly so    
called4  ,,socrates3 ,when1 therefore1  
perception is present to one of the     
seals or impressions but not to the     
other1 and the mind fits the seal of the
 absent perception on the one which is  
present1 in any case of this sort the   
mind is deceived2 in a word1 if our view
 is sound1 there can be no error or     
deception about things which a man does 
not know and has never perceived1 but   
only in things which are known and      
perceived2 in these alone opinion turns 
and twists about1 and becomes           
alternately true and false2--true when  
the seals and impressions of sense meet 
straight and opposite--false when they  
go awry and crooked4  ,,theaetetus3 ,and
 is not that1 ,socrates1 nobly said8    
,,socrates3 ,nobly6 yes2 but wait a     
little and hear the explanation1 and    
then you will say so with more reason2  
for to think truly is noble and to be   
deceived is base4  ,,theaetetus3        
,undoubtedly4  ,,socrates3 ,and the     

origin of truth and error is as         
follows3--,when the wax in the soul of  
any one is deep and abundant1 and smooth
 and perfectly tempered1 then the       
impressions which pass through the      
senses and sink into the heart of the   
soul1 as ,homer says in a parable1      
meaning to indicate the likeness of the 
soul to wax 7,kerh ,kerhos72 these1 ,i  
say1 being pure and clear1 and having a 
sufficient depth of wax1 are also       
lasting1 and minds1 such as these1      
easily learn and easily retain1 and are 
not liable to confusion1 but have true  
thoughts1 for they have plenty of room1 
and having clear impressions of things1 
as we term them1 quickly distribute them
 into their proper places on the block4 
,and such men are called wise4 ,do you  
agree8  ,,theaetetus3 ,entirely4        
,,socrates3 ,but when the heart of any  
one is shaggy--a quality which the      
all-wise poet commends1 or muddy and of 
impure wax1 or very soft1 or very hard1 
then there is a corresponding defect in 

the mind--the soft are good at learning1
 but apt to forget2 and the hard are the
 reverse2 the shaggy and rugged and     
gritty1 or those who have an admixture  
of earth or dung in their composition1  
have the impressions indistinct1 as also
 the hard1 for there is no depth in     
them2 and the soft too are indistinct1  
for their impressions are easily        
confused and effaced4 ,yet greater is   
the indistinctness when they are all    
jostled together in a little soul1 which
 has no room4 ,these are the natures    
which have false opinion2 for when they 
see or hear or think of anything1 they  
are slow in assigning the right objects 
to the right impressions--in their      
stupidity they confuse them1 and are apt
 to see and hear and think amiss--and   
such men are said to be deceived in     
their knowledge of objects1 and         
ignorant4  ,,theaetetus3 ,no man1       
,socrates1 can say anything truer than  
that4  ,,socrates3 ,then now we may     
admit the existence of false opinion in 

us8  ,,theaetetus3 ,certainly4          
,,socrates3 ,and of true opinion also8  
,,theaetetus3 ,yes4  ,,socrates3 ,we    
have at length satisfactorily proven    
beyond a doubt there are these two sorts
 of opinion8  ,,theaetetus3             
,undoubtedly4  ,,socrates3 ,alas1       
,theaetetus1 what a tiresome creature is
 a man who is fond of talking6          
,,theaetetus3 ,what makes you say so8   
,,socrates3 ,because ,i am disheartened 
at my own stupidity and tiresome        
garrulity2 for what other term will     
describe the habit of a man who is      
always arguing on all sides of a        
question2 whose dulness cannot be       
convinced1 and who will never leave off8
  ,,theaetetus3 ,but what puts you out  
of heart8  ,,socrates3 ,i am not only   
out of heart1 but in positive despair2  
for ,i do not know what to answer if any
 one were to ask me3--,o ,socrates1 have
 you indeed discovered that false       
opinion arises neither in the comparison
 of perceptions with one another nor yet

 in thought1 but in union of thought and
 perception8 ,yes1 ,i shall say1 with   
the complacence of one who thinks that  
he has made a noble discovery4          
,,theaetetus3 ,i see no reason why we   
should be ashamed of our demonstration1 
,socrates4  ,,socrates3 ,he will say3   
,you mean to argue that the man whom we 
only think of and do not see1 cannot be 
confused with the horse which we do not 
see or touch1 but only think of and do  
not perceive8 ,that ,i believe to be my 
meaning1 ,i shall reply4  ,,theaetetus3 
,quite right4  ,,socrates3 ,well1 then1 
he will say1 according to that argument1
 the number eleven1 which is only       
thought1 can never be mistaken for      
twelve1 which is only thought3 ,how     
would you answer him8  ,,theaetetus3 ,i 
should say that a mistake may very      
likely arise between the eleven or      
twelve which are seen or handled1 but   
that no similar mistake can arise       
between the eleven and twelve which are 
in the mind4  ,,socrates3 ,well1 but do 

you think that no one ever put before   
his own mind five and seven1--,i do not 
mean five or seven men or horses1 but   
five or seven in the abstract1 which1 as
 we say1 are recorded on the waxen      
block1 and in which false opinion is    
held to be impossible2 did no man ever  
ask himself how many these numbers make 
when added together1 and answer that    
they are eleven1 while another thinks   
that they are twelve1 or would all agree
 in thinking and saying that they are   
twelve8  ,,theaetetus3 ,certainly not2  
many would think that they are eleven1  
and in the higher numbers the chance of 
error is greater still2 for ,i assume   
you to be speaking of numbers in        
general4  ,,socrates3 ,exactly2 and ,i  
want you to consider whether this does  
not imply that the twelve in the waxen  
block are supposed to be eleven8        
,,theaetetus3 ,yes1 that seems to be the
 case4  ,,socrates3 ,then do we not come
 back to the old difficulty8 ,for he who
 makes such a mistake does think one    

thing which he knows to be another thing
 which he knows2 but this1 as we said1  
was impossible1 and afforded an         
irresistible proof of the non-existence 
of false opinion1 because otherwise the 
same person would inevitably know and   
not know the same thing at the same     
time4  ,,theaetetus3 ,most true4        
,,socrates3 ,then false opinion cannot  
be explained as a confusion of thought  
and sense1 for in that case we could not
 have been mistaken about pure          
conceptions of thought2 and thus we are 
obliged to say1 either that false       
opinion does not exist1 or that a man   
may not know that which he knows2--which
 alternative do you prefer8             
,,theaetetus3 ,it is hard to determine1 
,socrates4  ,,socrates3 ,and yet the    
argument will scarcely admit of both4   
,but1 as we are at our wits' end1       
suppose that we do a shameless thing8   
,,theaetetus3 ,what is it8  ,,socrates3 
,let us attempt to explain the verb 'to 
know4'  ,,theaetetus3 ,and why should   

that be shameless8  ,,socrates3 ,you    
seem not to be aware that the whole of  
our discussion from the very beginning  
has been a search after knowledge1 of   
which we are assumed not to know the    
nature4  ,,theaetetus3 ,nay1 but ,i am  
well aware4  ,,socrates3 ,and is it not 
shameless when we do not know what      
knowledge is1 to be explaining the verb 
'to know'8 ,the truth is1 ,theaetetus1  
that we have long been infected with    
logical impurity4 ,thousands of times   
have we repeated the words 'we know1'   
and 'do not know1' and 'we have or have 
not science or knowledge1' as if we     
could understand what we are saying to  
one another1 so long as we remain       
ignorant about knowledge2 and at this   
moment we are using the words 'we       
understand1' 'we are ignorant1' as      
though we could still employ them when  
deprived of knowledge or science4       
,,theaetetus3 ,but if you avoid these   
expressions1 ,socrates1 how will you    
ever argue at all8  ,,socrates3 ,i could

 not1 being the man ,i am4 ,the case    
would be different if ,i were a true    
hero of dialectic3 and ,o that such an  
one were present6 for he would have told
 us to avoid the use of these terms2 at 
the same time he would not have spared  
in you and me the faults which ,i have  
noted4 ,but1 seeing that we are no great
 wits1 shall ,i venture to say what     
knowing is8 for ,i think that the       
attempt may be worth making4            
,,theaetetus3 ,then by all means        
venture1 and no one shall find fault    
with you for using the forbidden terms4 
,,socrates3 ,you have heard the common  
explanation of the verb 'to know'8      
,,theaetetus3 ,i think so1 but ,i do not
 remember it at the moment4  ,,socrates3
 ,they explain the word 'to know' as    
meaning 'to have knowledge4'            
,,theaetetus3 ,true4  ,,socrates3 ,i    
should like to make a slight change1 and
 say 'to possess' knowledge4            
,,theaetetus3 ,how do the two           
expressions differ8  ,,socrates3        

,perhaps there may be no difference2 but
 still ,i should like you to hear my    
view1 that you may help me to test it4  
,,theaetetus3 ,i will1 if ,i can4       
,,socrates3 ,i should distinguish       
'having' from 'possessing'3 for example1
 a man may buy and keep under his       
control a garment which he does not     
wear2 and then we should say1 not that  
he has1 but that he possesses the       
garment4  ,,theaetetus3 ,it would be the
 correct expression4  ,,socrates3 ,well1
 may not a man 'possess' and yet not    
'have' knowledge in the sense of which  
,i am speaking8 ,as you may suppose a   
man to have caught wild birds--doves or 
any other birds--and to be keeping them 
in an aviary which he has constructed at
 home2 we might say of him in one sense1
 that he always has them because he     
possesses them1 might we not8           
,,theaetetus3 ,yes4  ,,socrates3 ,and   
yet1 in another sense1 he has none of   
them2 but they are in his power1 and he 
has got them under his hand in an       

enclosure of his own1 and can take and  
have them whenever he likes2--he can    
catch any which he likes1 and let the   
bird go again1 and he may do so as often
 as he pleases4  ,,theaetetus3 ,true4   
,,socrates3 ,once more1 then1 as in what
 preceded we made a sort of waxen       
figment in the mind1 so let us now      
suppose that in the mind of each man    
there is an aviary of all sorts of      
birds--some flocking together apart from
 the rest1 others in small groups1      
others solitary1 flying anywhere and    
everywhere4  ,,theaetetus3 ,let us      
imagine such an aviary--and what is to  
follow8  ,,socrates3 ,we may suppose    
that the birds are kinds of knowledge1  
and that when we were children1 this    
receptacle was empty2 whenever a man has
 gotten and detained in the enclosure a 
kind of knowledge1 he may be said to    
have learned or discovered the thing    
which is the subject of the knowledge3  
and this is to know4  ,,theaetetus3     
,granted4  ,,socrates3 ,and further1    

when any one wishes to catch any of     
these knowledges or sciences1 and having
 taken1 to hold it1 and again to let    
them go1 how will he express            
himself8--will he describe the          
'catching' of them and the original     
'possession' in the same words8 ,i will 
make my meaning clearer by an           
example3--,you admit that there is an   
art of arithmetic8  ,,theaetetus3 ,to be
 sure4  ,,socrates3 ,conceive this under
 the form of a hunt after the science of
 odd and even in general4  ,,theaetetus3
 ,i follow4  ,,socrates3 ,having the use
 of the art1 the arithmetician1 if ,i am
 not mistaken1 has the conceptions of   
number under his hand1 and can transmit 
them to another4  ,,theaetetus3 ,yes4   
,,socrates3 ,and when transmitting them 
he may be said to teach them1 and when  
receiving to learn them1 and when       
receiving to learn them1 and when having
 them in possession in the aforesaid    
aviary he may be said to know them4     
,,theaetetus3 ,exactly4  ,,socrates3    

,attend to what follows3 must not the   
perfect arithmetician know all numbers1 
for he has the science of all numbers in
 his mind8  ,,theaetetus3 ,true4        
,,socrates3 ,and he can reckon abstract 
numbers in his head1 or things about him
 which are numerable8  ,,theaetetus3 ,of
 course he can4  ,,socrates3 ,and to    
reckon is simply to consider how much   
such and such a number amounts to8      
,,theaetetus3 ,very true4  ,,socrates3  
,and so he appears to be searching into 
something which he knows1 as if he did  
not know it1 for we have already        
admitted that he knows all numbers2--you
 have heard these perplexing questions  
raised8  ,,theaetetus3 ,i have4         
,,socrates3 ,may we not pursue the image
 of the doves1 and say that the chase   
after knowledge is of two kinds8 one    
kind is prior to possession and for the 
sake of possession1 and the other for   
the sake of taking and holding in the   
hands that which is possessed already4  
,and thus1 when a man has learned and   

known something long ago1 he may resume 
and get hold of the knowledge which he  
has long possessed1 but has not at hand 
in his mind4  ,,theaetetus3 ,true4      
,,socrates3 ,that was my reason for     
asking how we ought to speak when an    
arithmetician sets about numbering1 or a
 grammarian about reading8 ,shall we    
say1 that although he knows1 he comes   
back to himself to learn what he already
 knows8  ,,theaetetus3 ,it would be too 
absurd1 ,socrates4  ,,socrates3 ,shall  
we say then that he is going to read or 
number what he does not know1 although  
we have admitted that he knows all      
letters and all numbers8  ,,theaetetus3 
,that1 again1 would be an absurdity4    
,,socrates3 ,then shall we say that     
about names we care nothing8--any one   
may twist and turn the words 'knowing'  
and 'learning' in any way which he      
likes1 but since we have determined that
 the possession of knowledge is not the 
having or using it1 we do assert that a 
man cannot not possess that which he    

possesses2 and1 therefore1 in no case   
can a man not know that which he knows1 
but he may get a false opinion about it2
 for he may have the knowledge1 not of  
this particular thing1 but of some      
other2--when the various numbers and    
forms of knowledge are flying about in  
the aviary1 and wishing to capture a    
certain sort of knowledge out of the    
general store1 he takes the wrong one by
 mistake1 that is to say1 when he       
thought eleven to be twelve1 he got hold
 of the ring-dove which he had in his   
mind1 when he wanted the pigeon4        
,,theaetetus3 ,a very rational          
explanation4  ,,socrates3 ,but when he  
catches the one which he wants1 then he 
is not deceived1 and has an opinion of  
what is1 and thus false and true opinion
 may exist1 and the difficulties which  
were previously raised disappear4 ,i    
dare say that you agree with me1 do you 
not8  ,,theaetetus3 ,yes4  ,,socrates3  
,and so we are rid of the difficulty of 
a man's not knowing what he knows1 for  

we are not driven to the inference that 
he does not possess what he possesses1  
whether he be or be not deceived4 ,and  
yet ,i fear that a greater difficulty is
 looking in at the window4              
,,theaetetus3 ,what is it8  ,,socrates3 
,how can the exchange of one knowledge  
for another ever become false opinion8  
,,theaetetus3 ,what do you mean8        
,,socrates3 ,in the first place1 how can
 a man who has the knowledge of anything
 be ignorant of that which he knows1 not
 by reason of ignorance1 but by reason  
of his own knowledge8 ,and1 again1 is it
 not an extreme absurdity that he should
 suppose another thing to be this1 and  
this to be another thing2--that1 having 
knowledge present with him in his mind1 
he should still know nothing and be     
ignorant of all things8--you might as   
well argue that ignorance may make a man
 know1 and blindness make him see1 as   
that knowledge can make him ignorant4   
,,theaetetus3 ,perhaps1 ,socrates1 we   
may have been wrong in making only forms

 of knowledge our birds3 whereas there  
ought to have been forms of ignorance as
 well1 flying about together in the     
mind1 and then he who sought to take one
 of them might sometimes catch a form of
 knowledge1 and sometimes a form of     
ignorance2 and thus he would have a     
false opinion from ignorance1 but a true
 one from knowledge1 about the same     
thing4  ,,socrates3 ,i cannot help      
praising you1 ,theaetetus1 and yet ,i   
must beg you to reconsider your words4  
,let us grant what you say--then1       
according to you1 he who takes ignorance
 will have a false opinion--am ,i right8
  ,,theaetetus3 ,yes4  ,,socrates3 ,he  
will certainly not think that he has a  
false opinion8  ,,theaetetus3 ,of course
 not4  ,,socrates3 ,he will think that  
his opinion is true1 and he will fancy  
that he knows the things about which he 
has been deceived8  ,,theaetetus3       
,certainly4  ,,socrates3 ,then he will  
think that he has captured knowledge and
 not ignorance8  ,,theaetetus3 ,clearly4

  ,,socrates3 ,and thus1 after going a  
long way round1 we are once more face to
 face with our original difficulty4 ,the
 hero of dialectic will retort upon     
us3--',o my excellent friends1 he will  
say1 laughing1 if a man knows the form  
of ignorance and the form of knowledge1 
can he think that one of them which he  
knows is the other which he knows8 or1  
if he knows neither of them1 can he     
think that the one which he knows not is
 another which he knows not8 or1 if he  
knows one and not the other1 can he     
think the one which he knows to be the  
one which he does not know8 or the one  
which he does not know to be the one    
which he knows8 or will you tell me that
 there are other forms of knowledge     
which distinguish the right and wrong   
birds1 and which the owner keeps in some
 other aviaries or graven on waxen      
blocks according to your foolish images1
 and which he may be said to know while 
he possesses them1 even though he have  
them not at hand in his mind8 ,and thus1

 in a perpetual circle1 you will be     
compelled to go round and round1 and you
 will make no progress4' ,what are we to
 say in reply1 ,theaetetus8             
,,theaetetus3 ,indeed1 ,socrates1 ,i do 
not know what we are to say4            
,,socrates3 ,are not his reproaches     
just1 and does not the argument truly   
show that we are wrong in seeking for   
false opinion until we know what        
knowledge is2 that must be first        
ascertained2 then1 the nature of false  
opinion8  ,,theaetetus3 ,i cannot but   
agree with you1 ,socrates1 so far as we 
have yet gone4  ,,socrates3 ,then1 once 
more1 what shall we say that knowledge  
is8--for we are not going to lose heart 
as yet4  ,,theaetetus3 ,certainly1 ,i   
shall not lose heart1 if you do not4    
,,socrates3 ,what definition will be    
most consistent with our former views8  
,,theaetetus3 ,i cannot think of any but
 our old one1 ,socrates4  ,,socrates3   
,what was it8  ,,theaetetus3 ,knowledge 
was said by us to be true opinion2 and  

true opinion is surely unerring1 and the
 results which follow from it are all   
noble and good4  ,,socrates3 ,he who led
 the way into the river1 ,theaetetus1   
said ',the experiment will show2' and   
perhaps if we go forward in the search1 
we may stumble upon the thing which we  
are looking for2 but if we stay where we
 are1 nothing will come to light4       
,,theaetetus3 ,very true2 let us go     
forward and try4  ,,socrates3 ,the trail
 soon comes to an end1 for a whole      
profession is against us4  ,,theaetetus3
 ,how is that1 and what profession do   
you mean8  ,,socrates3 ,the profession  
of the great wise ones who are called   
orators and lawyers2 for these persuade 
men by their art and make them think    
whatever they like1 but they do not     
teach them4 ,do you imagine that there  
are any teachers in the world so clever 
as to be able to convince others of the 
truth about acts of robbery or violence1
 of which they were not eye-witnesses1  
while a little water is flowing in the  

clepsydra8  ,,theaetetus3 ,certainly    
not1 they can only persuade them4       
,,socrates3 ,and would you not say that 
persuading them is making them have an  
opinion8  ,,theaetetus3 ,to be sure4    
,,socrates3 ,when1 therefore1 judges are
 justly persuaded about matters which   
you can know only by seeing them1 and   
not in any other way1 and when thus     
judging of them from report they attain 
a true opinion about them1 they judge   
without knowledge1 and yet are rightly  
persuaded1 if they have judged well4    
,,theaetetus3 ,certainly4  ,,socrates3  
,and yet1 ,o my friend1 if true opinion 
in law courts and knowledge are the     
same1 the perfect judge could not have  
judged rightly without knowledge2 and   
therefore ,i must infer that they are   
not the same4  ,,theaetetus3 ,that is a 
distinction1 ,socrates1 which ,i have   
heard made by some one else1 but ,i had 
forgotten it4 ,he said that true        
opinion1 combined with reason1 was      
knowledge1 but that the opinion which   

had no reason was out of the sphere of  
knowledge2 and that things of which     
there is no rational account are not    
knowable--such was the singular         
expression which he used--and that      
things which have a reason or           
explanation are knowable4  ,,socrates3  
,excellent2 but then1 how did he        
distinguish between things which are and
 are not 'knowable'8 ,i wish that you   
would repeat to me what he said1 and    
then ,i shall know whether you and ,i   
have heard the same tale4  ,,theaetetus3
 ,i do not know whether ,i can recall   
it2 but if another person would tell me1
 ,i think that ,i could follow him4     
,,socrates3 ,let me give you1 then1 a   
dream in return for a dream3--,methought
 that ,i too had a dream1 and ,i heard  
in my dream that the primeval letters or
 elements out of which you and ,i and   
all other things are compounded1 have no
 reason or explanation2 you can only    
name them1 but no predicate can be      
either affirmed or denied of them1 for  

in the one case existence1 in the other 
non-existence is already implied1       
neither of which must be added1 if you  
mean to speak of this or that thing by  
itself alone4 ,it should not be called  
itself1 or that1 or each1 or alone1 or  
this1 or the like2 for these go about   
everywhere and are applied to all       
things1 but are distinct from them2     
whereas1 if the first elements could be 
described1 and had a definition of their
 own1 they would be spoken of apart from
 all else4 ,but none of these primeval  
elements can be defined2 they can only  
be named1 for they have nothing but a   
name1 and the things which are          
compounded of them1 as they are complex1
 are expressed by a combination of      
names1 for the combination of names is  
the essence of a definition4 ,thus1     
then1 the elements or letters are only  
objects of perception1 and cannot be    
defined or known2 but the syllables or  
combinations of them are known and      
expressed1 and are apprehended by true  

opinion4 ,when1 therefore1 any one forms
 the true opinion of anything without   
rational explanation1 you may say that  
his mind is truly exercised1 but has no 
knowledge2 for he who cannot give and   
receive a reason for a thing1 has no    
knowledge of that thing2 but when he    
adds rational explanation1 then1 he is  
perfected in knowledge and may be all   
that ,i have been denying of him4 ,was  
that the form in which the dream        
appeared to you8  ,,theaetetus3         
,precisely4  ,,socrates3 ,and you allow 
and maintain that true opinion1 combined
 with definition or rational            
explanation1 is knowledge8              
,,theaetetus3 ,exactly4  ,,socrates3    
,then may we assume1 ,theaetetus1 that  
to-day1 and in this casual manner1 we   
have found a truth which in former times
 many wise men have grown old and have  
not found8  ,,theaetetus3 ,at any rate1 
,socrates1 ,i am satisfied with the     
present statement4  ,,socrates3 ,which  
is probably correct--for how can there  

be knowledge apart from definition and  
true opinion8 ,and yet there is one     
point in what has been said which does  
not quite satisfy me4  ,,theaetetus3    
,what was it8  ,,socrates3 ,what might  
seem to be the most ingenious notion of 
all3--,that the elements or letters are 
unknown1 but the combination or         
syllables known4  ,,theaetetus3 ,and was
 that wrong8  ,,socrates3 ,we shall soon
 know2 for we have as hostages the      
instances which the author of the       
argument himself used4  ,,theaetetus3   
,what hostages8  ,,socrates3 ,the       
letters1 which are the clements2 and the
 syllables1 which are the               
combinations2--he reasoned1 did he not1 
from the letters of the alphabet8       
,,theaetetus3 ,yes2 he did4  ,,socrates3
 ,let us take them and put them to the  
test1 or rather1 test ourselves3--,what 
was the way in which we learned letters8
 and1 first of all1 are we right in     
saying that syllables have a definition1
 but that letters have no definition8   

,,theaetetus3 ,i think so4  ,,socrates3 
,i think so too2 for1 suppose that some 
one asks you to spell the first syllable
 of my name3--,theaetetus1 he says1 what
 is ,,so8  ,,theaetetus3 ,i should reply
 ,s and ,o4  ,,socrates3 ,that is the   
definition which you would give of the  
syllable8  ,,theaetetus3 ,i should4     
,,socrates3 ,i wish that you would give 
me a similar definition of the ,s4      
,,theaetetus3 ,but how can any one1     
,socrates1 tell the elements of an      
element8 ,i can only reply1 that ,s is a
 consonant1 a mere noise1 as of the     
tongue hissing2 ,b1 and most other      
letters1 again1 are neither vowel-sounds
 nor noises4 ,thus letters may be most  
truly said to be undefined2 for even the
 most distinct of them1 which are the   
seven vowels1 have a sound only1 but no 
definition at all4  ,,socrates3 ,then1  
,i suppose1 my friend1 that we have been
 so far right in our idea about         
knowledge8  ,,theaetetus3 ,yes2 ,i think
 that we have4  ,,socrates3 ,well1 but  

have we been right in maintaining that  
the syllables can be known1 but not the 
letters8  ,,theaetetus3 ,i think so4    
,,socrates3 ,and do we mean by a        
syllable two letters1 or if there are   
more1 all of them1 or a single idea     
which arises out of the combination of  
them8  ,,theaetetus3 ,i should say that 
we mean all the letters4  ,,socrates3   
,take the case of the two letters ,s and
 ,o1 which form the first syllable of my
 own name2 must not he who knows the    
syllable1 know both of them8            
,,theaetetus3 ,certainly4  ,,socrates3  
,he knows1 that is1 the ,s and ,o8      
,,theaetetus3 ,yes4  ,,socrates3 ,but   
can he be ignorant of either singly and 
yet know both together8  ,,theaetetus3  
,such a supposition1 ,socrates1 is      
monstrous and unmeaning4  ,,socrates3   
,but if he cannot know both without     
knowing each1 then if he is ever to know
 the syllable1 he must know the letters 
first2 and thus the fine theory has     
again taken wings and departed4         

,,theaetetus3 ,yes1 with wonderful      
celerity4  ,,socrates3 ,yes1 we did not 
keep watch properly4 ,perhaps we ought  
to have maintained that a syllable is   
not the letters1 but rather one single  
idea framed out of them1 having a       
separate form distinct from them4       
,,theaetetus3 ,very true2 and a more    
likely notion than the other4           
,,socrates3 ,take care2 let us not be   
cowards and betray a great and imposing 
theory4  ,,theaetetus3 ,no1 indeed4     
,,socrates3 ,let us assume then1 as we  
now say1 that the syllable is a simple  
form arising out of the several         
combinations of harmonious elements--of 
letters or of any other elements4       
,,theaetetus3 ,very good4  ,,socrates3  
,and it must have no parts4             
,,theaetetus3 ,why8  ,,socrates3        
,because that which has parts must be a 
whole of all the parts4 ,or would you   
say that a whole1 although formed out of
 the parts1 is a single notion different
 from all the parts8  ,,theaetetus3 ,i  

should4  ,,socrates3 ,and would you say 
that all and the whole are the same1 or 
different8  ,,theaetetus3 ,i am not     
certain2 but1 as you like me to answer  
at once1 ,i shall hazard the reply1 that
 they are different4  ,,socrates3 ,i    
approve of your readiness1 ,theaetetus1 
but ,i must take time to think whether  
,i equally approve of your answer4      
,,theaetetus3 ,yes2 the answer is the   
point4  ,,socrates3 ,according to this  
new view1 the whole is supposed to      
differ from all8  ,,theaetetus3 ,yes4   
,,socrates3 ,well1 but is there any     
difference between all 7in the plural7  
and the all 7in the singular78 ,take the
 case of number3--,when we say one1 two1
 three1 four1 five1 six2 or when we say 
twice three1 or three times two1 or four
 and two1 or three and two and one1 are 
we speaking of the same or of different 
numbers8  ,,theaetetus3 ,of the same4   
,,socrates3 ,that is of six8            
,,theaetetus3 ,yes4  ,,socrates3 ,and in
 each form of expression we spoke of all

 the six8  ,,theaetetus3 ,true4         
,,socrates3 ,again1 in speaking of all  
7in the plural7 is there not one thing  
which we express8  ,,theaetetus3 ,of    
course there is4  ,,socrates3 ,and that 
is six8  ,,theaetetus3 ,yes4            
,,socrates3 ,then in predicating the    
word 'all' of things measured by number1
 we predicate at the same time a        
singular and a plural8  ,,theaetetus3   
,clearly we do4  ,,socrates3 ,again1 the
 number of the acre and the acre are the
 same2 are they not8  ,,theaetetus3     
,yes4  ,,socrates3 ,and the number of   
the stadium in like manner is the       
stadium8  ,,theaetetus3 ,yes4           
,,socrates3 ,and the army is the number 
of the army2 and in all similar cases1  
the entire number of anything is the    
entire thing8  ,,theaetetus3 ,true4     
,,socrates3 ,and the number of each is  
the parts of each8  ,,theaetetus3       
,exactly4  ,,socrates3 ,then as many    
things as have parts are made up of     
parts8  ,,theaetetus3 ,clearly4         

,,socrates3 ,but all the parts are      
admitted to be the all1 if the entire   
number is the all8  ,,theaetetus3 ,true4
  ,,socrates3 ,then the whole is not    
made up of parts1 for it would be the   
all1 if consisting of all the parts8    
,,theaetetus3 ,that is the inference4   
,,socrates3 ,but is a part a part of    
anything but the whole8  ,,theaetetus3  
,yes1 of the all4  ,,socrates3 ,you make
 a valiant defence1 ,theaetetus4 ,and   
yet is not the all that of which nothing
 is wanting8  ,,theaetetus3 ,certainly4 
,,socrates3 ,and is not a whole likewise
 that from which nothing is absent8 but 
that from which anything is absent is   
neither a whole nor all2--if wanting in 
anything1 both equally lose their       
entirety of nature4  ,,theaetetus3 ,i   
now think that there is no difference   
between a whole and all4  ,,socrates3   
,but were we not saying that when a     
thing has parts1 all the parts will be a
 whole and all8  ,,theaetetus3          
,certainly4  ,,socrates3 ,then1 as ,i   

was saying before1 must not the         
alternative be that either the syllable 
is not the letters1 and then the letters
 are not parts of the syllable1 or that 
the syllable will be the same with the  
letters1 and will therefore be equally  
known with them8  ,,theaetetus3 ,you are
 right4  ,,socrates3 ,and1 in order to  
avoid this1 we suppose it to be         
different from them8  ,,theaetetus3     
,yes4  ,,socrates3 ,but if letters are  
not parts of syllables1 can you tell me 
of any other parts of syllables1 which  
are not letters8  ,,theaetetus3 ,no1    
indeed1 ,socrates2 for if ,i admit the  
existence of parts in a syllable1 it    
would be ridiculous in me to give up    
letters and seek for other parts4       
,,socrates3 ,quite true1 ,theaetetus1   
and therefore1 according to our present 
view1 a syllable must surely be some    
indivisible form8  ,,theaetetus3 ,true4 
,,socrates3 ,but do you remember1 my    
friend1 that only a little while ago we 
admitted and approved the statement1    

that of the first elements out of which 
all other things are compounded there   
could be no definition1 because each of 
them when taken by itself is            
uncompounded2 nor can one rightly       
attribute to them the words 'being' or  
'this1' because they are alien and      
inappropriate words1 and for this reason
 the letters or elements were           
indefinable and unknown8  ,,theaetetus3 
,i remember4  ,,socrates3 ,and is not   
this also the reason why they are simple
 and indivisible8 ,i can see no other4  
,,theaetetus3 ,no other reason can be   
given4  ,,socrates3 ,then is not the    
syllable in the same case as the        
elements or letters1 if it has no parts 
and is one form8  ,,theaetetus3 ,to be  
sure4  ,,socrates3 ,if1 then1 a syllable
 is a whole1 and has many parts or      
letters1 the letters as well as the     
syllable must be intelligible and       
expressible1 since all the parts are    
acknowledged to be the same as the      
whole8  ,,theaetetus3 ,true4            

,,socrates3 ,but if it be one and       
indivisible1 then the syllables and the 
letters are alike undefined and unknown1
 and for the same reason8  ,,theaetetus3
 ,i cannot deny that4  ,,socrates3 ,we  
cannot1 therefore1 agree in the opinion 
of him who says that the syllable can be
 known and expressed1 but not the       
letters4  ,,theaetetus3 ,certainly not2 
if we may trust the argument4           
,,socrates3 ,well1 but will you not be  
equally inclined to disagree with him1  
when you remember your own experience in
 learning to read8  ,,theaetetus3 ,what 
experience8  ,,socrates3 ,why1 that in  
learning you were kept trying to        
distinguish the separate letters both by
 the eye and by the ear1 in order that1 
when you heard them spoken or saw them  
written1 you might not be confused by   
their position4  ,,theaetetus3 ,very    
true4  ,,socrates3 ,and is the education
 of the harp-player complete unless he  
can tell what string answers to a       
particular note2 the notes1 as every one

 would allow1 are the elements or       
letters of music8  ,,theaetetus3        
,exactly4  ,,socrates3 ,then1 if we     
argue from the letters and syllables    
which we know to other simples and      
compounds1 we shall say that the letters
 or simple elements as a class are much 
more certainly known than the syllables1
 and much more indispensable to a       
perfect knowledge of any subject2 and if
 some one says that the syllable is     
known and the letter unknown1 we shall  
consider that either intentionally or   
unintentionally he is talking nonsense8 
,,theaetetus3 ,exactly4  ,,socrates3    
,and there might be given other proofs  
of this belief1 if ,i am not mistaken4  
,but do not let us in looking for them  
lose sight of the question before us1   
which is the meaning of the statement1  
that right opinion with rational        
definition or explanation is the most   
perfect form of knowledge4              
,,theaetetus3 ,we must not4  ,,socrates3
 ,well1 and what is the meaning of the  

term 'explanation'8 ,i think that we    
have a choice of three meanings4        
,,theaetetus3 ,what are they8           
,,socrates3 ,in the first place1 the    
meaning may be1 manifesting one's       
thought by the voice with verbs and     
nouns1 imaging an opinion in the stream 
which flows from the lips1 as in a      
mirror or water4 ,does not explanation  
appear to be of this nature8            
,,theaetetus3 ,certainly2 he who so     
manifests his thought1 is said to       
explain himself4  ,,socrates3 ,and every
 one who is not born deaf or dumb is    
able sooner or later to manifest what he
 thinks of anything2 and if so1 all     
those who have a right opinion about    
anything will also have right           
explanation2 nor will right opinion be  
anywhere found to exist apart from      
knowledge4  ,,theaetetus3 ,true4        
,,socrates3 ,let us not1 therefore1     
hastily charge him who gave this account
 of knowledge with uttering an unmeaning
 word2 for perhaps he only intended to  

say1 that when a person was asked what  
was the nature of anything1 he should be
 able to answer his questioner by giving
 the elements of the thing4             
,,theaetetus3 ,as for example1          
,socrates4448  ,,socrates3 ,as1 for     
example1 when ,hesiod says that a waggon
 is made up of a hundred planks4 ,now1  
neither you nor ,i could describe all of
 them individually2 but if any one asked
 what is a waggon1 we should be content 
to answer1 that a waggon consists of    
wheels1 axle1 body1 rims1 yoke4         
,,theaetetus3 ,certainly4  ,,socrates3  
,and our opponent will probably laugh at
 us1 just as he would if we professed to
 be grammarians and to give a           
grammatical account of the name of      
,theaetetus1 and yet could only tell the
 syllables and not the letters of your  
name--that would be true opinion1 and   
not knowledge2 for knowledge1 as has    
been already remarked1 is not attained  
until1 combined with true opinion1 there
 is an enumeration of the elements out  

of which anything is composed4          
,,theaetetus3 ,yes4  ,,socrates3 ,in the
 same general way1 we might also have   
true opinion about a waggon2 but he who 
can describe its essence by an          
enumeration of the hundred planks1 adds 
rational explanation to true opinion1   
and instead of opinion has art and      
knowledge of the nature of a waggon1 in 
that he attains to the whole through the
 elements4  ,,theaetetus3 ,and do you   
not agree in that view1 ,socrates8      
,,socrates3 ,if you do1 my friend2 but  
,i want to know first1 whether you admit
 the resolution of all things into their
 elements to be a rational explanation  
of them1 and the consideration of them  
in syllables or larger combinations of  
them to be irrational--is this your     
view8  ,,theaetetus3 ,precisely4        
,,socrates3 ,well1 and do you conceive  
that a man has knowledge of any element 
who at one time affirms and at another  
time denies that element of something1  
or thinks that the same thing is        

composed of different elements at       
different times8  ,,theaetetus3         
,assuredly not4  ,,socrates3 ,and do you
 not remember that in your case and in  
that of others this often occurred in   
the process of learning to read8        
,,theaetetus3 ,you mean that ,i mistook 
the letters and misspelt the syllables8 
,,socrates3 ,yes4  ,,theaetetus3 ,to be 
sure2 ,i perfectly remember1 and ,i am  
very far from supposing that they who   
are in this condition have knowledge4   
,,socrates3 ,when a person at the time  
of learning writes the name of          
,theaetetus1 and thinks that he ought to
 write and does write ,th and e2 but1   
again1 meaning to write the name of     
,theododorus1 thinks that he ought to   
write and does write ,t and e--can we   
suppose that he knows the first         
syllables of your two names8            
,,theaetetus3 ,we have already admitted 
that such a one has not yet attained    
knowledge4  ,,socrates3 ,and in like    
manner be may enumerate without knowing 

them the second and third and fourth    
syllables of your name8  ,,theaetetus3  
,he may4  ,,socrates3 ,and in that case1
 when he knows the order of the letters 
and can write them out correctly1 he has
 right opinion8  ,,theaetetus3 ,clearly4
  ,,socrates3 ,but although we admit    
that he has right opinion1 he will still
 be without knowledge8  ,,theaetetus3   
,yes4  ,,socrates3 ,and yet he will have
 explanation1 as well as right opinion1 
for he knew the order of the letters    
when he wrote2 and this we admit to be  
explanation4  ,,theaetetus3 ,true4      
,,socrates3 ,then1 my friend1 there is  
such a thing as right opinion united    
with definition or explanation1 which   
does not as yet attain to the exactness 
of knowledge4  ,,theaetetus3 ,it would  
seem so4  ,,socrates3 ,and what we      
fancied to be a perfect definition of   
knowledge is a dream only4 ,but perhaps 
we had better not say so as yet1 for    
were there not three explanations of    
knowledge1 one of which must1 as we     

said1 be adopted by him who maintains   
knowledge to be true opinion combined   
with rational explanation8 ,and very    
likely there may be found some one who  
will not prefer this but the third4     
,,theaetetus3 ,you are quite right2     
there is still one remaining4 ,the first
 was the image or expression of the mind
 in speech2 the second1 which has just  
been mentioned1 is a way of reaching the
 whole by an enumeration of the         
elements4 ,but what is the third        
definition8  ,,socrates3 ,there is1     
further1 the popular notion of telling  
the mark or sign of difference which    
distinguishes the thing in question from
 all others4  ,,theaetetus3 ,can you    
give me any example of such a           
definition8  ,,socrates3 ,as1 for       
example1 in the case of the sun1 ,i     
think that you would be contented with  
the statement that the sun is the       
brightest of the heavenly bodies which  
revolve about the earth4  ,,theaetetus3 
,certainly4  ,,socrates3 ,understand    

why3--the reason is1 as ,i was just now 
saying1 that if you get at the          
difference and distinguishing           
characteristic of each thing1 then1 as  
many persons affirm1 you will get at the
 definition or explanation of it2 but   
while you lay hold only of the common   
and not of the characteristic notion1   
you will only have the definition of    
those things to which this common       
quality belongs4  ,,theaetetus3 ,i      
understand you1 and your account of     
definition is in my judgment correct4   
,,socrates3 ,but he1 who having right   
opinion about anything1 can find out the
 difference which distinguishes it from 
other things will know that of which    
before he had only an opinion4          
,,theaetetus3 ,yes2 that is what we are 
maintaining4  ,,socrates3 ,nevertheless1
 ,theaetetus1 on a nearer view1 ,i find 
myself quite disappointed2 the picture1 
which at a distance was not so bad1 has 
now become altogether unintelligible4   
,,theaetetus3 ,what do you mean8        

,,socrates3 ,i will endeavour to        
explain3 ,i will suppose myself to have 
true opinion of you1 and if to this ,i  
add your definition1 then ,i have       
knowledge1 but if not1 opinion only4    
,,theaetetus3 ,yes4  ,,socrates3 ,the   
definition was assumed to be the        
interpretation of your difference4      
,,theaetetus3 ,true4  ,,socrates3 ,but  
when ,i had only opinion1 ,i had no     
conception of your distinguishing       
characteristics4  ,,theaetetus3 ,i      
suppose not4  ,,socrates3 ,then ,i must 
have conceived of some general or common
 nature which no more belonged to you   
than to another4  ,,theaetetus3 ,true4  
,,socrates3 ,tell me1 now--,how in that 
case could ,i have formed a judgment of 
you any more than of any one else8      
,suppose that ,i imagine ,theaetetus to 
be a man who has nose1 eyes1 and mouth1 
and every other member complete2 how    
would that enable me to distinguish     
,theaetetus from ,theodorus1 or from    
some outer barbarian8  ,,theaetetus3    

,how could it8  ,,socrates3 ,or if ,i   
had further conceived of you1 not only  
as having nose and eyes1 but as having a
 snub nose and prominent eyes1 should ,i
 have any more notion of you than of    
myself and others who resemble me8      
,,theaetetus3 ,certainly not4           
,,socrates3 ,surely ,i can have no      
conception of ,theaetetus until your    
snub-nosedness has left an impression on
 my mind different from the             
snub-nosedness of all others whom ,i    
have ever seen1 and until your other    
peculiarities have a like distinctness2 
and so when ,i meet you to-morrow the   
right opinion will be re-called8        
,,theaetetus3 ,most true4  ,,socrates3  
,then right opinion implies the         
perception of differences8              
,,theaetetus3 ,clearly4  ,,socrates3    
,what1 then1 shall we say of adding     
reason or explanation to right opinion8 
,if the meaning is1 that we should form 
an opinion of the way in which something
 differs from another thing1 the        

proposal is ridiculous4  ,,theaetetus3  
,how so8  ,,socrates3 ,we are supposed  
to acquire a right opinion of the       
differences which distinguish one thing 
from another when we have already a     
right opinion of them1 and so we go     
round and round3--the revolution of the 
scytal1 or pestle1 or any other rotatory
 machine1 in the same circles1 is as    
nothing compared with such a            
requirement2 and we may be truly        
described as the blind directing the    
blind2 for to add those things which we 
already have1 in order that we may learn
 what we already think1 is like a soul  
utterly benighted4  ,,theaetetus3 ,tell 
me2 what were you going to say just now1
 when you asked the question8           
,,socrates3 ,if1 my boy1 the argument1  
in speaking of adding the definition1   
had used the word to 'know1' and not    
merely 'have an opinion' of the         
difference1 this which is the most      
promising of all the definitions of     
knowledge would have come to a pretty   

end1 for to know is surely to acquire   
knowledge4  ,,theaetetus3 ,true4        
,,socrates3 ,and so1 when the question  
is asked1 ,what is knowledge8 this fair 
argument will answer ',right opinion    
with knowledge1'--knowledge1 that is1 of
 difference1 for this1 as the said      
argument maintains1 is adding the       
definition4  ,,theaetetus3 ,that seems  
to be true4  ,,socrates3 ,but how       
utterly foolish1 when we are asking what
 is knowledge1 that the reply should    
only be1 right opinion with knowledge of
 difference or of anything6 ,and so1    
,theaetetus1 knowledge is neither       
sensation nor true opinion1 nor yet     
definition and explanation accompanying 
and added to true opinion8              
,,theaetetus3 ,i suppose not4           
,,socrates3 ,and are you still in labour
 and travail1 my dear friend1 or have   
you brought all that you have to say    
about knowledge to the birth8           
,,theaetetus3 ,i am sure1 ,socrates1    
that you have elicited from me a good   

deal more than ever was in me4          
,,socrates3 ,and does not my art show   
that you have brought forth wind1 and   
that the offspring of your brain are not
 worth bringing up8  ,,theaetetus3 ,very
 true4  ,,socrates3 ,but if1            
,theaetetus1 you should ever conceive   
afresh1 you will be all the better for  
the present investigation1 and if not1  
you will be soberer and humbler and     
gentler to other men1 and will be too   
modest to fancy that you know what you  
do not know4 ,these are the limits of my
 art2 ,i can no further go1 nor do ,i   
know aught of the things which great and
 famous men know or have known in this  
or former ages4 ,the office of a midwife
 ,i1 like my mother1 have received from 
,god2 she delivered women1 ,i deliver   
men2 but they must be young and noble   
and fair4  ,and now ,i have to go to the
 porch of the ,king ,archon1 where ,i am
 to meet ,meletus and his indictment4   
,to-morrow morning1 ,theodorus1 ,i shall
 hope to see you again at this place4