The Purpose of Education
The true analogy for this indwelling power in the soul and the instrument whereby each of us apprehends is that of an eye that could not be converted to the light from the darkness except by turning the whole body. Even so this organ of knowledge must be turned around from the world of becoming together with the entire soul, like the scene-shifting periactus in the theater, until the soul is able to endure the contemplation of essence and the brightest region of being. And this, we say, is the good, do we not?
Yes.
Of this very thing, then, I said, there might be an art, an art of the speediest and most effective shifting or conversion of the soul, not an art of producing vision in it, but on the assumption that it possesses vision but does not rightly direct it and does not look where it should, and art of bringing this about.