Theaetetus (191-194)

SOC. I will not tell you until I have tried to consider the matter in every way. For I should be ashamed of us, if, in our perplexity, we were forced to make such admissions as those to which I refer. But if we find the object of our quest, and are set free from perplexity, then, and not before, we will speak of others as involved in those absurdities, and we ourselves shall stand free from ridicule. But if we find no escape from our perplexity, we shall, I fancy, become low-spirited, like seasick people, and shall allow the argument to trample on us and do to us anything it pleases. Hear, then, by what means I still see a prospect of success for our quest.

THEAET. Do speak.

SOC. I shall deny that we were right when we agreed that it is impossible for a man to have opinion that the things he does not know are the things which he knows, and thus to be deceived. But there is a way in which it is possible.

THEAET. Do you mean what I myself suspected when we made the statement to which you refer, that sometimes I, though I know Socrates, saw at a distance someone whom I did not know, and thought it was Socrates whom I do know? In such a case false opinion does arise.

SOC. But did not we reject that, because it resulted in our knowing and not knowing the things which we know?

THEAET. Certainly we did.

SOC. Let us, then, not make that assumption, but another; perhaps it will turn out well for us, perhaps the opposite. But we are in such straits that we must turn every argument round and test it from all sides. Now see if this is sensible: Can a man who did not know a thing at one time learn it later?

THEAET. To be sure he can.

SOC. Again, then, can he learn one thing after another?

THEAET. Why not?

SOC. Please assume, then, for the sake of argument, that there is in our souls a block of wax, in one case larger, in another smaller, in one case the wax is purer, in another more impure and harder, in some cases softer, and in some of proper quality.

THEAET. I assume all that.

SOC. Let us, then, say that this is the gift of Memory, the mother of the Muses, and that whenever we wish to remember anything we see or hear or think of in our own minds, we hold this wax under the perceptions and thoughts and imprint them upon it, just as we make impressions from seal rings; and whatever is imprinted we remember and know as long as its image lasts, but whatever is rubbed out or cannot be imprinted we forget and do not know.

THEAET. Let us assume that.

SOC. Now take a man who knows the things which he sees and hears, and is considering some one of them; observe whether he may not gain a false opinion in the following manner.

THEAET. In what manner?

SOC. By thinking that the things which he knows are sometimes things which he knows and sometimes things which he does not know. For we were wrong before in agreeing that this is impossible.

THEAET. What do you say about it now?

SOC. We must begin our discussion of the matter by making the following distinctions: It is impossible for anyone to think that one thing which he knows and of which he has received a memorial imprint in his soul, but which he does not perceive, is another thing which he knows and of which also he has an imprint, and which he does not perceive. And, again, he cannot think that what he knows is that which he does not know and of which he has no seal; nor that what he does not know is another thing which he does not know; nor that what he does not know is what he knows; nor can he think that what he perceives is something else which he perceives; nor that what he perceives is something which he does not perceive; nor that what he does not perceive is something else which he does not perceive; nor that what he does not perceive is something which he perceives. And, again, it is still more impossible, if that can be, to think that a thing which he knows and perceives and of which he has an imprint which accords with the perception is another thing which he knows and perceives and of which he has an imprint which accords with the perception. And he cannot think that what he knows and perceives and of which he has a correct memorial imprint is another thing which he knows; nor that a thing which he knows and perceives and of which he has such an imprint is another thing which he perceives; nor again that a thing which he neither knows nor perceives is another thing which he neither knows nor perceives; nor that a thing which he neither knows nor perceives is another thing which he does not know; nor that a thing which he neither knows nor perceives is another thing which he does not perceive. In all these cases it is impossible beyond everything for false opinion to arise in the mind of anyone. The possibility that it may arise remains, if anywhere, in the following cases.

THEAET. What cases are they? I hope they may help me to understand better; for now I cannot follow you.

SOC. The cases in which he may think that things which he knows are some other things which he knows and perceives; or which he does not know, but perceives; or that things which he knows and perceives are other things which he knows and perceives.

THEAET. Now I am even more out of the running than before.

SOC. Then let me repeat it in a different way. I know Theodorus and remember within myself what sort of a person he is, and just so I know Theaetetus, but sometimes I see them, and sometimes I do not, sometimes I touch them, sometimes not, sometimes I hear them or perceive them through some other sense, and sometimes I have no perception of you at all, but I remember you none the less and know you in my own mind. Is it not so?

THEAET. Certainly.

SOC. This, then, is the first of the points which I wish to make clear. Note that one may perceive or not perceive that which one knows.

THEAET. That is true.

SOC. So, too, with that which he does not know—he may often not even perceive it, and often he may merely perceive it?

THEAET. That too is possible.

SOC. See if you follow me better now. If Socrates knows Theodorus and Theaetetus, but sees neither of them and has no other perception of them, he never could have the opinion within himself that Theaetetus is Theodorus. Am I right or wrong?

THEAET. You are right.

SOC. Now that was the first of the cases of which I spoke.

THEAET. Yes, it was.

SOC. The second is this: knowing one of you and not knowing the other, and not perceiving either of you, I never could think that the one whom I know is the one whom I do not know.

THEAET. Right.

SOC. And this is the third case: not knowing and not perceiving either of you, I could not think that he whom I do not know is someone else whom I do not know. And imagine that you have heard all the other cases again in succession, in which I could never form false opinions about you and Theodorus, either when I know or do not know both of you, or when I know one and not the other; and the same is true if we say perceive instead of know. Do you follow me?

THEAET. I follow you.

SOC. Then the possibility of forming false opinion remains in the following case: when, for example, knowing you and Theodorus, and having on that block of wax the imprint of both of you, as if you were signet-rings, but seeing you both at a distance and indistinctly, I hasten to assign the proper imprint of each of you to the proper vision, and to make it fit, as it were, its own footprint, with the purpose of causing recognition; [*] but I may fail in this by interchanging them, and put the vision of one upon the imprint of the other, as people put a shoe on the wrong foot; or, again, I may be affected as the sight is affected when we use a mirror and the sight as it flows makes a change from right to left, and thus make a mistake; it is in such cases, then, that interchanged opinion occurs and the forming of false opinion arises.

THEAET. I think it does, Socrates. You describe what happens to opinion marvelously well.

SOC. There is still the further case, when, knowing both of you, I perceive one in addition to knowing him, but do not perceive the other, and the knowledge which I have of that other is not in accord with my perception. This is the case I described in this way before, and at that time you did not understand me.

THEAET. No, I did not.

SOC. This is what I meant, that if anyone knows and perceives one of you, and has knowledge of him which accords with the perception, he will never think that he is someone else whom he knows and perceives and his knowledge of whom accords with the perception. That was the case, was it not?

THEAET. Yes.

SOC. But we omitted, I believe, the case of which I am speaking now—the case in which we say the false opinion arises: when a man knows both and sees both (or has some other perception of them), but fails to hold the two imprints each under its proper perception; like a bad archer he shoots beside the mark and misses it; and it is just this which is called error or deception.

THEAET. And properly so.

SOC. Now when perception is present to one of the imprints but not to the other, and the mind applies the imprint of the absent perception to the perception which is present, the mind is deceived in every such instance. In a word, if our present view is sound, false opinion or deception seems to be impossible in relation to things which one does not know and has never perceived; but it is precisely in relation to things which we know and perceive that opinion turns and twists, becoming false and true—true when it puts the proper imprints and seals fairly and squarely upon one another, and false when it applies them sideways and aslant.

THEAET. Well, then, Socrates, is that view not a good one?

SOC. After you have heard the rest, you will be still more inclined to say so. For to hold a true opinion is a good thing, but to be deceived is a disgrace.

THEAET. Certainly.

SOC. They say the cause of these variations is as follows: When the wax in the soul of a man is deep and abundant and smooth and properly kneaded, the images that come through the perceptions are imprinted upon this heart of the soul—as Homer calls it in allusion to its similarity to wax [*]—; when this is the case, and in such men, the imprints, being clear and of sufficient depth, are also lasting. And men of this kind are in the first place quick to learn, and secondly they have retentive memories, and moreover they do not interchange the imprints of their perceptions, but they have true opinions. For the imprints are clear and have plenty of room, so that such men quickly assign them to their several moulds, which are called realities; and these men, then, are called wise. Or do you not agree?

THEAET. Most emphatically.

SOC. Now when the heart of anyone is shaggy (a condition which the all-wise poet commends), or when it is unclean or of impure wax, or very soft or hard, those whose wax is soft are quick to learn, but forgetful, and those in whom it is hard are the reverse. But those in whom it is shaggy and rough and stony, infected with earth or dung which is mixed in it, receive indistinct imprints from the moulds.