For me, my thoughts are my prostitutes.

If your little savage were left to himself and be allowed to retain all his ignorance, he would in time join the infant's reasoning to the grown man's passion, he would strangle his father and sleep with his mother.

Wandering in a vast forest at night, I have only a faint light to guide me. A stranger appears and says to me: 'My friend, you should blow out your candle in order to find your way more clearly.' This stranger is a theologian.

Those who fear the facts will forever try to discredit the fact-finders.

A thing is not proved just because no one has ever questioned it. What has never been gone into impartially has never been properly gone into. Hence scepticism is the first step toward truth. It must be applied generally, because it is the touchstone.

Anyone who takes it upon himself, on his private authority, to break a bad law, thereby authorizes everyone else to break the good ones.

The most dangerous madmen are those created by religion, and people whose aim is to disrupt society always know how to make good use of them on occasion.