226
Stranger
Str. To such as these: we say sift and strain and winnow and separate. Apparently a term descriptive of some part of the process of weaving; cf. Plat. Crat. 338b.
Theaetetus
Theaet. Certainly.
Stranger
Str. And besides these there are card and comb and beat the web and countless other technical terms which we know. Is it not so?
Theaetetus
Theaet. Why do you use these as examples and ask about them all? What do you wish to show in regard to them?
10
Stranger
Str. All those that I have mentioned imply a notion of division.
Stranger
Str. Then since there is, accorling to my reckoning, one art involved in all of these operations, let us give it one name.
Theaetetus
Theaet. What shall we call it?
Stranger
Str. The art of discrimination.
15
Theaetetus
Theaet. Very well.
Stranger
Str. Now see if we can discover two divisions of this.
Theaetetus
Theaet. You demand quick thinking, for a boy like me.
Stranger
Str. And yet, in the instance of discrimination just mentioned there was, first, the separation of worse from better, and, secondly, of like from like.
Theaetetus
Theaet. Yes, as you now express it, that is pretty clear.
20
Stranger
Str. Now I know no common name for the second kind of discrimination; but I do know the name of the kind which retains the better and throws away the worse.
Theaetetus
Theaet. What is it?
Stranger
Str. Every such discrimination, as I think, is universally called a sort of purification.
Theaetetus
Theaet. Yes, so it is.
Stranger
Str. And could not anyone see that purification is of two kinds?
25
Theaetetus
Theaet. Yes, perhaps, in time; but still I do not see it now.
