Dialogues

case, when he knows the order of the letters and can write them out correctly, he has right opinion? Theaetetus Clearly. Socrates But although we admit that he has right opinion, he will still be without knowledge? Theaetetus Yes. Socrates And yet he will have explanation, as well as right opinion, for he knew the order of the letters when he wrote; and this we admit to be explanation. Theaetetus True. Socrates Then, my friend, there is such a thing as right opinion united with definition or explanation, which does not as yet attain to the exactness of knowledge. Theaetetus It would seem so. Socrates And what we fancied to be a perfect definition of knowledge is a dream only. But perhaps we had better not say so as yet, for were there not three explanations of knowledge, one of which must, as we said, be adopted by him who maintains knowledge to be true opinion combined with rational explanation? And very likely there may be found someone who will not prefer this but the third. Theaetetus You are quite right; there is still one remaining. The first was the image or expression of the mind in speech; the second, which has just been mentioned, is a way of reaching the whole by an enumeration of the elements. But what is the third definition? Socrates There is, further, the popular notion of telling the mark or sign of difference which distinguishes the thing in question from all others. Theaetetus Can you give me any example of such a definition? Socrates As, for example, in the case of the sun, I think that you would be contented with the statement that the sun is the brightest of the heavenly bodies which revolve about the earth. Theaetetus Certainly. Socrates Understand why:⁠—the reason is, as I was just now saying, that if you get at the difference and distinguishing characteristic of each thing, then, as many persons affirm, you will get at the definition or explanation of it; but while you lay hold only of the common and not of the characteristic notion, you will only have the definition of those things to which this common quality belongs. Theaetetus I understand you, and your account of definition is in my judgment correct. Socrates But he, who having right opinion about anything, can find out the difference which distinguishes it from other things will know that of which before he had only an opinion. Theaetetus Yes; that is what we are maintaining. Socrates Nevertheless, Theaetetus, on a nearer view, I find myself quite disappointed; the picture, which at a distance was not so bad, has now become altogether unintelligible. Theaetetus What do you mean? Socrates I will endeavour to explain: I will suppose myself to have true opinion of you, and if to this I add your definition, then I have knowledge, but if not, opinion only. Theaetetus Yes. Socrates The definition was assumed to be the interpretation of your difference. Theaetetus True. Socrates But when I had only opinion, I had no conception of your distinguishing characteristics. Theaetetus I suppose not. Socrates Then I must have conceived of some general or common nature which no more belonged to you than to another. Theaetetus True. Socrates Tell me, now⁠—How in that case could I have formed a judgment of you any more than of anyone else? Suppose that I imagine Theaetetus to be a man who has nose, eyes, and mouth, and every other member complete; how would that enable me to distinguish Theaetetus from Theodorus, or from some outer barbarian? Theaetetus How could it? Socrates Or if I had further conceived of you, not only as having nose and eyes, but as having a snub nose and prominent eyes, should I have any more notion of you than of myself and others who resemble me? Theaetetus Certainly not. Socrates 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 seen, and until your other peculiarities have a like distinctness; and so when I meet you tomorrow the right opinion will be recalled? Theaetetus Most true. Socrates Then right opinion implies the perception of differences? Theaetetus Clearly. Socrates What, then, shall we say of adding reason or explanation to right opinion? If the meaning is, that we should form an opinion of the way in which something differs from another thing, the proposal is ridiculous. Theaetetus How so? Socrates 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 them, and so we go round and round:⁠—the revolution of the scytal, or pestle, or any other rotatory machine, in the same circles, is as nothing compared with such a requirement; and we may be truly described as the blind directing the blind; for to add those things which we already have, in order that we may learn what we already think, is like a soul utterly benighted. Theaetetus Tell me; what were you going to say just now, when you asked the question? Socrates If, my boy, the argument, in speaking of adding the definition, had used the word to “know,” and not merely “have an opinion” of the difference, this which is the most promising of all the definitions of knowledge would have come to a pretty end, for to know is surely to acquire knowledge. Theaetetus True. Socrates And so, when the question is asked, What is knowledge? this fair argument will answer “Right opinion with knowledge,”⁠—knowledge, that is, of difference, for this, as the said argument maintains, is adding the definition. Theaetetus That seems to be true. Socrates But how utterly foolish, when we are asking what is knowledge, that the reply should only be, right opinion with knowledge of difference or of anything! And so, Theaetetus, knowledge is neither sensation nor true opinion, nor yet definition and explanation accompanying and added to true opinion? Theaetetus I suppose not. Socrates And are you still in labour and travail, my dear friend, or have you brought all that you have to say about knowledge to the birth? Theaetetus I am sure, Socrates, that you