And the same things look bent and straight when seen in water and out of it, and also both concave and convex, due to the sight's being mislead by the colors, and every sort of confusion of this kind is plainly in our soul. And, then, it is because they take advantage of this affection in our nature that shadow painting, and puppeteering, and many other tricks of the kind fall nothing short of wizardry.

Admitting one's ignorance is the first step in acquiring knowledge.

I believe that we cannot live better than in seeking to become better, nor more agreeably than having a clear conscience.

I am a citizen, not of Athens, or Greece, but of the world.

A man should inure himself to voluntary labor, and not give up to indulgence and pleasure, as they beget no good constitution of body nor knowledge of mind.

My belief is that to have no wants is divine.

I have lived long enough to learn how much there is I can really do without.... He is nearest to God who needs the fewest things.