The most intolerable pain is produced by prolonging the keenest pleasure.

The philosopher is Nature's pilot. And there you have our difference: to be in hell is to drift: to be in heaven is to steer.

All censorships exist to prevent anyone from challenging current conceptions and existing institutions. All progress is initiated by challenging current conceptions, and executed by supplanting existing institutions. Consequently, the first condition of progress is the removal of censorship.

Youth is just wasted on young people.

What is wrong with priests and popes is that instead of being apostles and saints, they are nothing but empirics who say I know instead of I am learning, and pray for credulity and inertia as wise men pray for skepticism and activity.

Geniuses are horrid, intolerant, easily offended, sleeplessly self-conscious men, who expect their wives to be angels with no further business in life than to pet and worship their husbands. Even at the best they are not comfortable men to live with; and a perfect husband is one who is perfectly comfortable to live with.

Without art, the crudeness of reality would make the world unbearable.