The Republic by Plato Part 9 Page 42

Proceed.

Say, then, is not pleasure opposed to pain?

True.

And there is a neutral state which is neither pleasure nor pain?

There is.

A state which is intermediate, and a sort of repose of the soul about either — that is what you mean?

Yes.

You remember what people say when they are sick?

What do they say?

That after all nothing is pleasanter than health. But then they never knew this to be the greatest of pleasures until they were ill.

Yes, I know, he said.