Science is a cemetary of dead ideas.

Cure yourself of the affliction of caring how you appear to others. Concern yourself only with how you appear before God, concern yourself only with the idea that God may have of you.

My work...is to shatter the faith of men here, there, and everywhere, faith in affirmation, faith in negation, and faith in abstention from faith, and this for the sake of faith in faith itself.

What we believe to be the motives of our conduct are usually but the pretexts for it.

Hell has been conceived as a police institution, to inspire fear in this world. But the worst of it all is that it no longer frightens anyone, and therefore it will have to be closed down.

And usually [the philosopher] philosophizes either in order to resign himself to life, or to seek some finality in it, or to distract himself and forget his griefs, or for pastime and amusement.

If a person never contradicts himself, it must be that he says nothing.