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Part 34

Theaetetus · 428? BCE-348? BCE Plato — chapter 34 of 44 · ~798 words · public domain

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THEAETETUS: I see no reason why we should be ashamed of our demonstration, Socrates.

SOCRATES: He will say: You mean to argue that the man whom we only think of and do not see, cannot be confused with the horse which we do not see or touch, but only think of and do not perceive? That I believe to be my meaning, I shall reply.

THEAETETUS: Quite right.

SOCRATES: Well, then, he will say, according to that argument, the number eleven, which is only thought, can never be mistaken for twelve, which is only thought: How would you answer him?

THEAETETUS: I should say that a mistake may very likely arise between the eleven or twelve which are seen or handled, but that no similar mistake can arise between the eleven and twelve which are in the mind.

SOCRATES: Well, but do you think that no one ever put before his own mind five and seven,--I do not mean five or seven men or horses, but five or seven in the abstract, which, as we say, are recorded on the waxen block, and in which false opinion is held to be impossible; did no man ever ask himself how many these numbers make when added together, and answer that they are eleven, while another thinks that they are twelve, or would all agree in thinking and saying that they are twelve?

THEAETETUS: Certainly not; many would think that they are eleven, and in the higher numbers the chance of error is greater still; for I assume you to be speaking of numbers in general.

SOCRATES: Exactly; and I want you to consider whether this does not imply that the twelve in the waxen block are supposed to be eleven?

THEAETETUS: Yes, that seems to be the case.

SOCRATES: Then do we not come back to the old difficulty? For he who makes such a mistake does think one thing which he knows to be another thing which he knows; but this, as we said, was impossible, and afforded an irresistible proof of the non-existence of false opinion, because otherwise the same person would inevitably know and not know the same thing at the same time.

THEAETETUS: Most true.

SOCRATES: Then false opinion cannot be explained as a confusion of thought and sense, for in that case we could not have been mistaken about pure conceptions of thought; and thus we are obliged to say, either that false opinion does not exist, or that a man may not know that which he knows;--which alternative do you prefer?

THEAETETUS: It is hard to determine, Socrates.

SOCRATES: And yet the argument will scarcely admit of both. But, as we are at our wits' end, suppose that we do a shameless thing?

THEAETETUS: What is it?

SOCRATES: Let us attempt to explain the verb 'to know.'

THEAETETUS: And why should that be shameless?

SOCRATES: You seem not to be aware that the whole of our discussion from the very beginning has been a search after knowledge, of which we are assumed not to know the nature.

THEAETETUS: Nay, but I am well aware.

SOCRATES: And is it not shameless when we do not know what knowledge is, to be explaining the verb 'to know'? The truth is, Theaetetus, that we have long been infected with logical impurity. Thousands of times have we repeated the words 'we know,' and 'do not know,' and 'we have or have not science or knowledge,' as if we could understand what we are saying to one another, so long as we remain ignorant about knowledge; and at this moment we are using the words 'we understand,' 'we are ignorant,' as though we could still employ them when deprived of knowledge or science.

THEAETETUS: But if you avoid these expressions, Socrates, how will you ever argue at all?

SOCRATES: I could not, being the man I am. The case would be different if I were a true hero of dialectic: and O that such an one were present! for he would have told us to avoid the use of these terms; at the same time he would not have spared in you and me the faults which I have noted. But, seeing that we are no great wits, shall I venture to say what knowing is? for I think that the attempt may be worth making.

THEAETETUS: Then by all means venture, and no one shall find fault with you for using the forbidden terms.

SOCRATES: You have heard the common explanation of the verb 'to know'?

THEAETETUS: I think so, but I do not remember it at the moment.

SOCRATES: They explain the word 'to know' as meaning 'to have knowledge.'

THEAETETUS: True.

SOCRATES: I should like to make a slight change, and say 'to possess' knowledge.

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