Sophist

Str. For deformity there is gymnastics, and for disease medicine.

Theaet. That is clear.

Str. Hence for insolence and injustice and cowardice is not the corrective art the one of all arts most closely related to Justice?

Theaet. Probably it is, at least according to the judgement of mankind.

Str. And for all sorts of ignorance is there any art it would be more correct to suggest than that of instruction?

Theaet. No, none.

Str. Come now, think. Shall we say that there is only one kind of instruction, or that there are more and that two are the most important?

Theaet. I am thinking.

Str. I think we can find out most quickly in this way.

Theaet. In what way?

Str. By seeing whether ignorance admits of being cut in two in the middle; for if ignorance turns out to be twofold, it is clear that instruction must also consist of two parts, one for each part of ignorance.

Theaet. Well, can you see what you are now looking for?

Str. I at any rate think I do see one large and grievous kind of ignorance, separate from the rest, and as weighty as all the other parts put together.

Theaet. What is it?

Str. Thinking that one knows a thing when one does not know it. Through this, I believe, all the mistakes of the mind are caused in all of us.

Theaet. True.

Str. And furthermore to this kind of ignorance alone the name of stupidity is given.

Theaet. Certainly.

Str. Now what name is to be given to that part of instruction which gets rid of this?

Theaet. I think, Stranger, that the other part is called instruction in handicraft, and that this part is here at Athens through our influence called education.

Str. And so it is, Theaetetus, among nearly all the Hellenes. But we must examine further and see whether it is one and indivisible or still admits of division important enough to have a name.

Theaet. Yes, we must see about that.

Str. I think there is still a way in which this also may be divided.

Theaet. On what principle?

Str. Of instruction in arguments one method seems to be rougher, and the other section smoother.

Theaet. What shall we call each of these?