All the arts are brothers; each one is a light to the others.

True greatness consists in the use of a powerful understanding to enlighten oneself and others.

Monsieur l'abbé, I detest what you write, but I would give my life to make it possible for you to continue to write.

Men are equal; it is not birth but virtue that makes the difference.

Do you think... that men have always massacred each other, as they do today? Have they always been liars, cheats, traitors, brigands, weak, flighty, cowardly, envious, gluttonous, drunken, grasping, and vicious, bloody, backbiting, debauched, fanatical, hypocritical, and silly?

When he who hears does not know what he who speaks means, and when he who speaks does not know what he himself means, that is philosophy.

The malevolence of men revealed itself to his mind in all of its ugliness