Sophist

Str. Observe, then, that we have now been just in time in carrying our point against the supporters of such doctrine, and in forcing them to admit that one thing mingles with another.

Theaet. What was our object?

Str. Our object was to establish discourse as one of our classes of being. For if we were deprived of this, we should be deprived of philosophy, which would be the greatest calamity; moreover, we must at the present moment come to an agreement about the nature of discourse, and if we were robbed of it by its absolute non-existence, we could no longer discourse; and we should be robbed of it if we agreed that there is no mixture of anything with anything.

Theaet. That is true enough; but I do not understand why we must come to an agreement about discourse just now.

Str. Perhaps the easiest way for you to understand is by following this line of argument.

Theaet. What line?

Str. We found that not-being was one of the classes of being, permeating all being.

Theaet. Yes.

Str. So the next thing is to inquire whether it mingles with opinion and speech.

Theaet. Why?

Str. If it does not mingle with them, the necessary result is that all things are true, but if it does, then false opinion and false discourse come into being; for to think or say what is not—that is, I suppose, falsehood arising in mind or in words.

Theaet. So it is.

Str. But if falsehood exists, deceit exists.

Theaet. Yes.

Str. And if deceit exists, all things must be henceforth full of images and likenesses and fancies.

Theaet. Of course.

Str. But we said that the sophist had taken refuge in this region and had absolutely denied the existence of falsehood: for he said that not-being could be neither conceived nor uttered, since not-being did not in any way participate in being.

Theaet. Yes, so it was.

Str. But now not-being has been found to partake of being, and so, perhaps, he would no longer keep up the fight in this direction; but he might say that some ideas partake of not-being and some do not, and that speech and opinion are among those which do not; and he would therefore again contend that the image-making and fantastic art, in which we placed him, has absolutely no existence, since opinion and speech have no participation in not-being; for falsehood cannot possibly exist unless such participation takes place.