THEAETETUS: True.
SOCRATES: Then appearing and perceiving coincide in the case of hot and
cold, and in similar instances; for things appear, or may be supposed to
be, to each one such as he perceives them?
THEAETETUS: Yes.
SOCRATES: Then perception is always of existence, and being the same as
knowledge is unerring?
THEAETETUS: Clearly.
SOCRATES: In the name of the Graces, what an almighty wise man
Protagoras must have been! He spoke these things in a parable to the
common herd, like you and me, but told the truth, 'his Truth,' (In
allusion to a book of Protagoras' which bore this title.) in secret to
his own disciples.
THEAETETUS: What do you mean, Socrates?
SOCRATES: I am about to speak of a high argument, in which all things
are said to be relative; you cannot rightly call anything by any name,
such as great or small, heavy or light, for the great will be small and
the heavy light--there is no single thing or quality, but out of motion
and change and admixture all things are becoming relatively to one
another, which 'becoming' is by us incorrectly called being, but is
really becoming, for nothing ever is, but all things are becoming.
Summon all philosophers--Protagoras, Heracleitus, Empedocles, and the
rest of them, one after another, and with the exception of Parmenides
they will agree with you in this. Summon the great masters of either
kind of poetry--Epicharmus, the prince of Comedy, and Homer of Tragedy;
when the latter sings of
'Ocean whence sprang the gods, and mother Tethys,'
does he not mean that all things are the offspring, of flux and motion?
THEAETETUS: I think so.
SOCRATES: And who could take up arms against such a great army having
Homer for its general, and not appear ridiculous? (Compare Cratylus.)
THEAETETUS: Who indeed, Socrates?
SOCRATES: Yes, Theaetetus; and there are plenty of other proofs
which will show that motion is the source of what is called being and
becoming, and inactivity of not-being and destruction; for fire and
warmth, which are supposed to be the parent and guardian of all other
things, are born of movement and of friction, which is a kind of
motion;--is not this the origin of fire?
THEAETETUS: It is.
SOCRATES: And the race of animals is generated in the same way?
THEAETETUS: Certainly.
SOCRATES: And is not the bodily habit spoiled by rest and idleness, but
preserved for a long time by motion and exercise?
THEAETETUS: True.
SOCRATES: And what of the mental habit? Is not the soul informed, and
improved, and preserved by study and attention, which are motions; but
when at rest, which in the soul only means want of attention and study,
is uninformed, and speedily forgets whatever she has learned?
THEAETETUS: True.
SOCRATES: Then motion is a good, and rest an evil, to the soul as well
as to the body?
THEAETETUS: Clearly.
SOCRATES: I may add, that breathless calm, stillness and the like waste
and impair, while wind and storm preserve; and the palmary argument of
all, which I strongly urge, is the golden chain in Homer, by which
he means the sun, thereby indicating that so long as the sun and the
heavens go round in their orbits, all things human and divine are and
are preserved, but if they were chained up and their motions ceased,
then all things would be destroyed, and, as the saying is, turned upside
down.
THEAETETUS: I believe, Socrates, that you have truly explained his
meaning.
SOCRATES: Then now apply his doctrine to perception, my good friend, and
first of all to vision; that which you call white colour is not in your
eyes, and is not a distinct thing which exists out of them. And you must
not assign any place to it: for if it had position it would be, and be
at rest, and there would be no process of becoming.
THEAETETUS: Then what is colour?
SOCRATES: Let us carry the principle which has just been affirmed, that
nothing is self-existent, and then we shall see that white, black,
and every other colour, arises out of the eye meeting the appropriate
motion, and that what we call a colour is in each case neither the
active nor the passive element, but something which passes between
them, and is peculiar to each percipient; are you quite certain that the
several colours appear to a dog or to any animal whatever as they appear
to you?
THEAETETUS: Far from it.
SOCRATES: Or that anything appears the same to you as to another man?
Are you so profoundly convinced of this? Rather would it not be true
that it never appears exactly the same to you, because you are never
exactly the same?
THEAETETUS: The latter.
SOCRATES: And if that with which I compare myself in size, or which
I apprehend by touch, were great or white or hot, it could not become
different by mere contact with another unless it actually changed; nor
again, if the comparing or apprehending subject were great or white
or hot, could this, when unchanged from within, become changed by any
approximation or affection of any other thing. The fact is that in
our ordinary way of speaking we allow ourselves to be driven into most
ridiculous and wonderful contradictions, as Protagoras and all who take
his line of argument would remark.
THEAETETUS: How? and of what sort do you mean?
SOCRATES: A little instance will sufficiently explain my meaning: Here
are six dice, which are more by a half when compared with four, and
fewer by a half than twelve--they are more and also fewer. How can you
or any one maintain the contrary?
THEAETETUS: Very true.
SOCRATES: Well, then, suppose that Protagoras or some one asks whether
anything can become greater or more if not by increasing, how would you
answer him, Theaetetus?
THEAETETUS: I should say 'No,' Socrates, if I were to speak my mind
in reference to this last question, and if I were not afraid of
contradicting my former answer.
SOCRATES: Capital! excellent! spoken like an oracle, my boy! And if you
reply 'Yes,' there will be a case for Euripides; for our tongue will be
unconvinced, but not our mind. (In allusion to the well-known line of
Euripides, Hippol.: e gloss omomoch e de thren anomotos.)
THEAETETUS: Very true.
SOCRATES: The thoroughbred Sophists, who know all that can be known
about the mind, and argue only out of the superfluity of their wits,
would have had a regular sparring-match over this, and would have
knocked their arguments together finely. But you and I, who have no
professional aims, only desire to see what is the mutual relation of
these principles,--whether they are consistent with each or not.
THEAETETUS: Yes, that would be my desire.
SOCRATES: And mine too. But since this is our feeling, and there is
plenty of time, why should we not calmly and patiently review our own
thoughts, and thoroughly examine and see what these appearances in
us really are? If I am not mistaken, they will be described by us as
follows:--first, that nothing can become greater or less, either in
number or magnitude, while remaining equal to itself--you would agree?
THEAETETUS: Yes.
SOCRATES: Secondly, that without addition or subtraction there is no
increase or diminution of anything, but only equality.
THEAETETUS: Quite true.
SOCRATES: Thirdly, that what was not before cannot be afterwards,
without becoming and having become.
THEAETETUS: Yes, truly.
SOCRATES: These three axioms, if I am not mistaken, are fighting with
one another in our minds in the case of the dice, or, again, in such a
case as this--if I were to say that I, who am of a certain height and
taller than you, may within a year, without gaining or losing in height,
be not so tall--not that I should have lost, but that you would have
increased. In such a case, I am afterwards what I once was not, and yet
I have not become; for I could not have become without becoming, neither
could I have become less without losing somewhat of my height; and I
could give you ten thousand examples of similar contradictions, if
we admit them at all. I believe that you follow me, Theaetetus; for I
suspect that you have thought of these questions before now.
THEAETETUS: Yes, Socrates, and I am amazed when I think of them; by the
Gods I am! and I want to know what on earth they mean; and there are
times when my head quite swims with the contemplation of them.
SOCRATES: I see, my dear Theaetetus, that Theodorus had a true insight
into your nature when he said that you were a philosopher, for wonder
is the feeling of a philosopher, and philosophy begins in wonder. He was
not a bad genealogist who said that Iris (the messenger of heaven)
is the child of Thaumas (wonder). But do you begin to see what is the
explanation of this perplexity on the hypothesis which we attribute to
Protagoras?
THEAETETUS: Not as yet.
SOCRATES: Then you will be obliged to me if I help you to unearth the
hidden 'truth' of a famous man or school.
THEAETETUS: To be sure, I shall be very much obliged.
SOCRATES: Take a look round, then, and see that none of the uninitiated
are listening. Now by the uninitiated I mean the people who believe in
nothing but what they can grasp in their hands, and who will not allow
that action or generation or anything invisible can have real existence.
THEAETETUS: Yes, indeed, Socrates, they are very hard and impenetrable
mortals.
SOCRATES: Yes, my boy, outer barbarians. Far more ingenious are the
brethren whose mysteries I am about to reveal to you. Their first
principle is, that all is motion, and upon this all the affections of
which we were just now speaking are supposed to depend: there is nothing
but motion, which has two forms, one active and the other passive, both
in endless number; and out of the union and friction of them there is
generated a progeny endless in number, having two forms, sense and the
object of sense, which are ever breaking forth and coming to the birth
at the same moment. The senses are variously named hearing, seeing,
smelling; there is the sense of heat, cold, pleasure, pain, desire,
fear, and many more which have names, as well as innumerable others
which are without them; each has its kindred object,--each variety
of colour has a corresponding variety of sight, and so with sound and
hearing, and with the rest of the senses and the objects akin to them.
Do you see, Theaetetus, the bearings of this tale on the preceding
argument?
THEAETETUS: Indeed I do not.
SOCRATES: Then attend, and I will try to finish the story. The purport
is that all these things are in motion, as I was saying, and that this
motion is of two kinds, a slower and a quicker; and the slower elements
have their motions in the same place and with reference to things near
them, and so they beget; but what is begotten is swifter, for it
is carried to fro, and moves from place to place. Apply this to
sense:--When the eye and the appropriate object meet together and give
birth to whiteness and the sensation connatural with it, which could not
have been given by either of them going elsewhere, then, while the
sight is flowing from the eye, whiteness proceeds from the object which
combines in producing the colour; and so the eye is fulfilled with
sight, and really sees, and becomes, not sight, but a seeing eye;
and the object which combined to form the colour is fulfilled with
whiteness, and becomes not whiteness but a white thing, whether wood or
stone or whatever the object may be which happens to be coloured white.
And this is true of all sensible objects, hard, warm, and the like,
which are similarly to be regarded, as I was saying before, not as
having any absolute existence, but as being all of them of whatever kind
generated by motion in their intercourse with one another; for of the
agent and patient, as existing in separation, no trustworthy conception,
as they say, can be formed, for the agent has no existence until united
with the patient, and the patient has no existence until united with
the agent; and that which by uniting with something becomes an agent, by
meeting with some other thing is converted into a patient. And from
all these considerations, as I said at first, there arises a general
reflection, that there is no one self-existent thing, but everything
is becoming and in relation; and being must be altogether abolished,
although from habit and ignorance we are compelled even in this
discussion to retain the use of the term. But great philosophers tell us
that we are not to allow either the word 'something,' or 'belonging to
something,' or 'to me,' or 'this,' or 'that,' or any other detaining
name to be used, in the language of nature all things are being created
and destroyed, coming into being and passing into new forms; nor can any
name fix or detain them; he who attempts to fix them is easily refuted.
And this should be the way of speaking, not only of particulars but
of aggregates; such aggregates as are expressed in the word 'man,' or
'stone,' or any name of an animal or of a class. O Theaetetus, are not
these speculations sweet as honey? And do you not like the taste of them
in the mouth?
THEAETETUS: I do not know what to say, Socrates; for, indeed, I cannot
make out whether you are giving your own opinion or only wanting to draw
me out.
SOCRATES: You forget, my friend, that I neither know, nor profess to
know, anything of these matters; you are the person who is in labour, I
am the barren midwife; and this is why I soothe you, and offer you one
good thing after another, that you may taste them. And I hope that I may
at last help to bring your own opinion into the light of day: when this
has been accomplished, then we will determine whether what you have
brought forth is only a wind-egg or a real and genuine birth. Therefore,
keep up your spirits, and answer like a man what you think.
THEAETETUS: Ask me.
SOCRATES: Then once more: Is it your opinion that nothing is but what
becomes?--the good and the noble, as well as all the other things which
we were just now mentioning?
THEAETETUS: When I hear you discoursing in this style, I think that
there is a great deal in what you say, and I am very ready to assent.
SOCRATES: Let us not leave the argument unfinished, then; for there
still remains to be considered an objection which may be raised about
dreams and diseases, in particular about madness, and the various
illusions of hearing and sight, or of other senses. For you know that
in all these cases the esse-percipi theory appears to be unmistakably
refuted, since in dreams and illusions we certainly have false
perceptions; and far from saying that everything is which appears, we
should rather say that nothing is which appears.
THEAETETUS: Very true, Socrates.
SOCRATES: But then, my boy, how can any one contend that knowledge is
perception, or that to every man what appears is?
THEAETETUS: I am afraid to say, Socrates, that I have nothing to answer,
because you rebuked me just now for making this excuse; but I certainly
cannot undertake to argue that madmen or dreamers think truly, when they
imagine, some of them that they are gods, and others that they can fly,
and are flying in their sleep.
SOCRATES: Do you see another question which can be raised about these
phenomena, notably about dreaming and waking?
THEAETETUS: What question?
SOCRATES: A question which I think that you must often have heard
persons ask:--How can you determine whether at this moment we are
sleeping, and all our thoughts are a dream; or whether we are awake, and
talking to one another in the waking state?
THEAETETUS: Indeed, Socrates, I do not know how to prove the one
any more than the other, for in both cases the facts precisely
correspond;--and there is no difficulty in supposing that during all
this discussion we have been talking to one another in a dream; and when
in a dream we seem to be narrating dreams, the resemblance of the two
states is quite astonishing.
SOCRATES: You see, then, that a doubt about the reality of sense is
easily raised, since there may even be a doubt whether we are awake
or in a dream. And as our time is equally divided between sleeping
and waking, in either sphere of existence the soul contends that the
thoughts which are present to our minds at the time are true; and during
one half of our lives we affirm the truth of the one, and, during the
other half, of the other; and are equally confident of both.
THEAETETUS: Most true.
SOCRATES: And may not the same be said of madness and other disorders?
the difference is only that the times are not equal.
THEAETETUS: Certainly.
SOCRATES: And is truth or falsehood to be determined by duration of
time?
THEAETETUS: That would be in many ways ridiculous.
SOCRATES: But can you certainly determine by any other means which of
these opinions is true?
THEAETETUS: I do not think that I can.
SOCRATES: Listen, then, to a statement of the other side of the
argument, which is made by the champions of appearance. They would say,
as I imagine--Can that which is wholly other than something, have the
same quality as that from which it differs? and observe, Theaetetus,
that the word 'other' means not 'partially,' but 'wholly other.'
THEAETETUS: Certainly, putting the question as you do, that which is
wholly other cannot either potentially or in any other way be the same.
SOCRATES: And must therefore be admitted to be unlike?
THEAETETUS: True.
SOCRATES: If, then, anything happens to become like or unlike itself or
another, when it becomes like we call it the same--when unlike, other?
THEAETETUS: Certainly.
SOCRATES: Were we not saying that there are agents many and infinite,
and patients many and infinite?
THEAETETUS: Yes.
SOCRATES: And also that different combinations will produce results
which are not the same, but different?
THEAETETUS: Certainly.
SOCRATES: Let us take you and me, or anything as an example:--There is
Socrates in health, and Socrates sick--Are they like or unlike?
THEAETETUS: You mean to compare Socrates in health as a whole, and
Socrates in sickness as a whole?
SOCRATES: Exactly; that is my meaning.
THEAETETUS: I answer, they are unlike.
SOCRATES: And if unlike, they are other?
THEAETETUS: Certainly.
SOCRATES: And would you not say the same of Socrates sleeping and
waking, or in any of the states which we were mentioning?
THEAETETUS: I should.
SOCRATES: All agents have a different patient in Socrates, accordingly
as he is well or ill.
THEAETETUS: Of course.
SOCRATES: And I who am the patient, and that which is the agent, will
produce something different in each of the two cases?
THEAETETUS: Certainly.
SOCRATES: The wine which I drink when I am in health, appears sweet and
pleasant to me?
THEAETETUS: True.
SOCRATES: For, as has been already acknowledged, the patient and agent
meet together and produce sweetness and a perception of sweetness, which
are in simultaneous motion, and the perception which comes from the
patient makes the tongue percipient, and the quality of sweetness which
arises out of and is moving about the wine, makes the wine both to be
and to appear sweet to the healthy tongue.
THEAETETUS: Certainly; that has been already acknowledged.
SOCRATES: But when I am sick, the wine really acts upon another and a
different person?
THEAETETUS: Yes.
SOCRATES: The combination of the draught of wine, and the Socrates
who is sick, produces quite another result; which is the sensation of
bitterness in the tongue, and the motion and creation of bitterness in
and about the wine, which becomes not bitterness but something bitter;
as I myself become not perception but percipient?
THEAETETUS: True.
SOCRATES: There is no other object of which I shall ever have the same
perception, for another object would give another perception, and would
make the percipient other and different; nor can that object which
affects me, meeting another subject, produce the same, or become
similar, for that too would produce another result from another subject,
and become different.
THEAETETUS: True.
SOCRATES: Neither can I by myself, have this sensation, nor the object
by itself, this quality.
THEAETETUS: Certainly not.
SOCRATES: When I perceive I must become percipient of something--there
can be no such thing as perceiving and perceiving nothing; the object,
whether it become sweet, bitter, or of any other quality, must have
relation to a percipient; nothing can become sweet which is sweet to no
one.
THEAETETUS: Certainly not.
SOCRATES: Then the inference is, that we (the agent and patient) are or
become in relation to one another; there is a law which binds us one to
the other, but not to any other existence, nor each of us to himself;
and therefore we can only be bound to one another; so that whether
a person says that a thing is or becomes, he must say that it is or
becomes to or of or in relation to something else; but he must not
say or allow any one else to say that anything is or becomes
absolutely:--such is our conclusion.
THEAETETUS: Very true, Socrates.
SOCRATES: Then, if that which acts upon me has relation to me and to no
other, I and no other am the percipient of it?
THEAETETUS: Of course.
SOCRATES: Then my perception is true to me, being inseparable from my
own being; and, as Protagoras says, to myself I am judge of what is and
what is not to me.
THEAETETUS: I suppose so.
SOCRATES: How then, if I never err, and if my mind never trips in the
conception of being or becoming, can I fail of knowing that which I
perceive?
THEAETETUS: You cannot.
SOCRATES: Then you were quite right in affirming that knowledge is only
perception; and the meaning turns out to be the same, whether with Homer
and Heracleitus, and all that company, you say that all is motion and
flux, or with the great sage Protagoras, that man is the measure of all
things; or with Theaetetus, that, given these premises, perception is
knowledge. Am I not right, Theaetetus, and is not this your new-born
child, of which I have delivered you? What say you?
THEAETETUS: I cannot but agree, Socrates.
SOCRATES: Then this is the child, however he may turn out, which you and
I have with difficulty brought into the world. And now that he is born,
we must run round the hearth with him, and see whether he is worth
rearing, or is only a wind-egg and a sham. Is he to be reared in any
case, and not exposed? or will you bear to see him rejected, and not get
into a passion if I take away your first-born?
THEODORUS: Theaetetus will not be angry, for he is very good-natured.
But tell me, Socrates, in heaven's name, is this, after all, not the
truth?
SOCRATES: You, Theodorus, are a lover of theories, and now you
innocently fancy that I am a bag full of them, and can easily pull one
out which will overthrow its predecessor. But you do not see that in
reality none of these theories come from me; they all come from him who
talks with me. I only know just enough to extract them from the wisdom
of another, and to receive them in a spirit of fairness. And now I shall
say nothing myself, but shall endeavour to elicit something from our
young friend.
THEODORUS: Do as you say, Socrates; you are quite right.
SOCRATES: Shall I tell you, Theodorus, what amazes me in your
acquaintance Protagoras?
THEODORUS: What is it?
SOCRATES: I am charmed with his doctrine, that what appears is to
each one, but I wonder that he did not begin his book on Truth with a
declaration that a pig or a dog-faced baboon, or some other yet stranger
monster which has sensation, is the measure of all things; 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 tadpole, not to speak of his
fellow-men--would not this have produced an overpowering effect? For
if truth is only sensation, and no man can discern another's feelings
better than he, or has any superior right to determine whether his
opinion is true or false, but each, as we have several times repeated,
is to himself the sole judge, and everything that he judges is true and
right, why, my friend, should Protagoras be preferred to the place
of wisdom and instruction, and deserve to be well paid, and we poor
ignoramuses have to go to him, if each one is the measure of his own
wisdom? Must he not be talking 'ad captandum' in all this? I say nothing
of the ridiculous predicament in which my own midwifery and the whole
art of dialectic is placed; for the attempt to supervise or refute the
notions or opinions of others would be a tedious and enormous piece of
folly, if to each man his own are right; and this must be the case if
Protagoras' Truth is the real truth, and the philosopher is not merely
amusing himself by giving oracles out of the shrine of his book.
THEODORUS: He was a friend of mine, Socrates, as you were saying, and
therefore I cannot have him refuted by my lips, nor can I oppose you
when I agree with you; please, then, to take Theaetetus again; he seemed
to answer very nicely.
SOCRATES: If you were to go into a Lacedaemonian palestra, Theodorus,
would you have a right to look on at the naked wrestlers, some of them
making a poor figure, if you did not strip and give them an opportunity
of judging of your own person?
THEODORUS: Why not, Socrates, if they would allow me, as I think you
will, in consideration of my age and stiffness; let some more supple
youth try a fall with you, and do not drag me into the gymnasium.
SOCRATES: Your will is my will, Theodorus, as the proverbial
philosophers say, and therefore I will return to the sage Theaetetus:
Tell me, Theaetetus, in reference to what I was saying, are you not
lost in wonder, like myself, when you find that all of a sudden you are
raised to the level of the wisest of men, or indeed of the gods?--for
you would assume the measure of Protagoras to apply to the gods as well
as men?
THEAETETUS: Certainly I should, and I confess to you that I am lost in
wonder. At first hearing, I was quite satisfied with the doctrine, that
whatever appears is to each one, but now the face of things has changed.
SOCRATES: Why, my dear boy, you are young, and therefore your ear
is quickly caught and your mind influenced by popular arguments.
Protagoras, or some one speaking on his behalf, will doubtless say in
reply,--Good people, young and old, you meet and harangue, and bring
in the gods, whose existence or non-existence I banish from writing and
speech, or you talk about the reason of man being degraded to the level
of the brutes, which is a telling argument with the multitude, but not
one word of proof or demonstration do you offer. All is probability with
you, 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 importance. He or any other mathematician who argued from
probabilities and likelihoods in geometry, would not be worth an ace.
THEAETETUS: But neither you nor we, Socrates, would be satisfied with
such arguments.
SOCRATES: Then you and Theodorus mean to say that we must look at the
matter in some other way?
THEAETETUS: Yes, in quite another way.
SOCRATES: And the way will be to ask whether perception is or is not the
same as knowledge; for this was the real point of our argument, and with
a view to this we raised (did we not?) those many strange questions.
THEAETETUS: Certainly.
SOCRATES: Shall we say that we know every thing which we see and hear?
for example, shall we say that not having learned, we do not hear the
language of foreigners when they speak to us? or shall we say that
we not only hear, but know what they are saying? Or again, if we see
letters which we do not understand, shall we say that we do not see
them? or shall we aver that, seeing them, we must know them?
THEAETETUS: We shall say, Socrates, that we know what we actually see
and hear of them--that is to say, we see and know the figure and colour
of the letters, and we hear and know the elevation or depression of the
sound of them; but we do not perceive by sight and hearing, or know,
that which grammarians and interpreters teach about them.
SOCRATES: Capital, Theaetetus; and about this there shall be no dispute,
because I want you to grow; but there is another difficulty coming,
which you will also have to repulse.
THEAETETUS: What is it?
SOCRATES: Some one will say, Can a man who has ever known anything, and
still has and preserves a memory of that which he knows, not know that
which he remembers at the time when he remembers? I have, I fear, a
tedious way of putting a simple question, which is only, whether a man
who has learned, and remembers, can fail to know?
THEAETETUS: Impossible, Socrates; the supposition is monstrous.
SOCRATES: Am I talking nonsense, then? Think: is not seeing perceiving,
and is not sight perception?
THEAETETUS: True.
SOCRATES: And if our recent definition holds, every man knows that which
he has seen?
THEAETETUS: Yes.
SOCRATES: And you would admit that there is such a thing as memory?
THEAETETUS: Yes.
SOCRATES: And is memory of something or of nothing?
THEAETETUS: Of something, surely.
SOCRATES: Of things learned and perceived, that is?
THEAETETUS: Certainly.
SOCRATES: Often a man remembers that which he has seen?
THEAETETUS: True.
SOCRATES: And if he closed his eyes, would he forget?
THEAETETUS: Who, Socrates, would dare to say so?
SOCRATES: But we must say so, if the previous argument is to be
maintained.
THEAETETUS: What do you mean? I am not quite sure that I understand you,
though I have a strong suspicion that you are right.
SOCRATES: As thus: he who sees knows, as we say, that which he sees; for
perception and sight and knowledge are admitted to be the same.
THEAETETUS: Certainly.
SOCRATES: But he who saw, and has knowledge of that which he saw,
remembers, when he closes his eyes, that which he no longer sees.
THEAETETUS: True.
SOCRATES: And seeing is knowing, and therefore not-seeing is
not-knowing?
THEAETETUS: Very true.
SOCRATES: Then the inference is, that a man may have attained the
knowledge of something, which he may remember and yet not know, because
he does not see; and this has been affirmed by us to be a monstrous
supposition.
THEAETETUS: Most true.
SOCRATES: Thus, then, the assertion that knowledge and perception are
one, involves a manifest impossibility?
THEAETETUS: Yes.
SOCRATES: Then they must be distinguished?
THEAETETUS: I suppose that they must.
SOCRATES: Once more we shall have to begin, and ask 'What is knowledge?'
and yet, Theaetetus, what are we going to do?
THEAETETUS: About what?
SOCRATES: Like a good-for-nothing cock, without having won the victory,
we walk away from the argument and crow.
THEAETETUS: How do you mean?
SOCRATES: After the manner of disputers (Lys.; Phaedo; Republic), we
were satisfied with mere verbal consistency, and were well pleased if in
this way we could gain an advantage. Although professing not to be mere
Eristics, but philosophers, I suspect that we have unconsciously fallen
into the error of that ingenious class of persons.
THEAETETUS: I do not as yet understand you.
SOCRATES: Then I will try to explain myself: just now we asked the
question, whether a man who had learned and remembered could fail to
know, and we showed that a person who had seen might remember when he
had his eyes shut and could not see, and then he would at the same
time remember and not know. But this was an impossibility. And so the
Protagorean fable came to nought, and yours also, who maintained that
knowledge is the same as perception.
THEAETETUS: True.
SOCRATES: And yet, my friend, I rather suspect that the result would
have been different if Protagoras, who was the father of the first of
the two brats, had been alive; he would have had a great deal to say on
their behalf. But he is dead, and we insult over his orphan child; and
even the guardians whom he left, and of whom our friend Theodorus is
one, are unwilling to give any help, and therefore I suppose that I must
take up his cause myself, and see justice done?
THEODORUS: Not I, Socrates, but rather Callias, the son of Hipponicus,
is guardian of his orphans. I was too soon diverted from the
abstractions of dialectic to geometry. Nevertheless, I shall be grateful
to you if you assist him.
SOCRATES: Very good, Theodorus; you shall see how I will come to the
rescue. If a person does not attend to the meaning of terms as they are
commonly used in argument, he may be involved even in greater paradoxes
than these. Shall I explain this matter to you or to Theaetetus?
THEODORUS: To both of us, and let the younger answer; he will incur less
disgrace if he is discomfited.
SOCRATES: Then now let me ask the awful question, which is this:--Can a
man know and also not know that which he knows?
THEODORUS: How shall we answer, Theaetetus?
THEAETETUS: He cannot, I should say.
SOCRATES: He can, if you maintain that seeing is knowing. When you are
imprisoned in a well, as the saying is, and the self-assured adversary
closes one of your eyes with his hand, and asks whether you can see
his cloak with the eye which he has closed, how will you answer the
inevitable man?