The proof that man is the noblest of all creatures is that no other creature has ever denied it.

He who says he hates every kind of flattery, and says it in earnest, certainly does not yet know every kind of flattery.

We now possess four principles of morality: 1) a philosophical: do good for its own sake, out of respect for the law; 2) a religious: do good because it is God's will, out of love of God; 3) a human: do good because it will promote your happiness, out of self-love; 4) a political: do good because it will promote the welfare of the society of which you are a part, out of love of society having regard to yourself. But is this not all one single principle, only viewed from different sides?

God: personified incomprehensibility.

The great rule: If the little bit you have is nothing special in itself, at least find a way of saying it that is a little bit special.

The construction of the universe is certainly very much easier to explain than is that of the plant.

When an acquaintance goes by I often step back from my window, not so much to spare him the effort of acknowledging me as to spare myself the embarrassment of seeing that he has not done so.