Nowadays three witty turns of phrase and a lie make a writer.

Non cogitant, ergo non sunt.

A clever child brought up with a foolish one can itself become foolish. Man is so perfectible and corruptible he can become a fool through good sense.

To see every day how people get the name 'genius' just as the wood-lice in the cellar the name 'millipede'-not because they have that many feet, but because most people don't want to count to 14-this has had the result that I don't believe anyone any more without checking.

Whenever he composes a critical review, I have been told, he gets an enormous erection.

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?

It is in the gift for employing all the vicissitudes of life to one's own advantage and to that of one's craft that a large part of genius consists.