Mutual cheating is the foundation of society.

It is not from space that I must seek my dignity, but from the government of my thought. I shall have no more if I possess worlds. By space the universe encompasses and swallows me up like an atom; by thought I comprehend the world.

Fear not, provided you fear; but if you fear not, then fear.

Kind words do not cost much. They never blister the tongue or lips. They make other people good-natured. They also produce their own image on men's souls, and a beautiful image it is.

Nothing gives rest but the sincere search for truth.

What part of us feels pleasure? Is it our hand, our arm, our flesh, or our blood? It must obviously be something immaterial.

The sum of a man's problems come from his inability to be alone in a silent room.