I am a good Protestant, and in the full sense of the term, for from the bottom of my soul, I protest against everything that is said, and everything that is done.

The antiquity and general acceptance of an opinion is not assurance of its truth.

No nations are more warlike than those which profess Christianity.

It is pure illusion to think that an opinion which passes down from century to century, from generation to generation, may not be entirely false.

It is thus tolerance that is the source of peace, and intolerance that is the source of disorder and squabbling.

Properly speaking, history is nothing but the crimes and misfortunes of the human race.

I get up and retire when I wish. I go out if I wish and I do not go out if I do not desire to do so, except for the two days on which I give lectures.