Dialogues

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 Someone 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,313 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? Theaetetus I should answer, “Not with that eye but with the other.” Socrates Then you see and do not see the same thing at the same time. Theaetetus Yes, in a certain sense. Socrates None of that, he will reply; I do not ask or bid you answer in what sense you know, but only whether you know that which you do not know. You have been proved to see that which you do not see; and you have already admitted that seeing is knowing, and that not-seeing is not-knowing: I leave you to draw the inference. Theaetetus Yes; the inference is the contradictory of my assertion. Socrates Yes, my marvel, and there might have