All the dignity of man consists in thought. Thought is therefore by its nature a wonderful and incomparable thing. It must have strange defects to be contemptible. But it has such, so that nothing is more ridiculous. How great it is in its nature! How vile it is in its defects! But what is this thought? How foolish it is!

As men are not able to fight against death, misery, ignorance, they have taken it into their heads, in order to be happy, not to think of them at all.

Few friendships would survive if each one knew what his friend says of him behind his back.

Justice is what is established; and thus all our established laws will necessarily be regarded as just without examination, since they are established.

Il n'est pas certain que tout soit incertain. (Translation: It is not certain that everything is uncertain.)

Sneezing absorbs all the functions of the soul just as much as the [sexual] act, but we do not draw from it the same conclusions against the greatness of man, because it is involuntary; although we bring it about, we do so involuntarily. It is not for the sake of the thing in itself but for another end, and is therefore not a sign of man's weakness, or his subjection to this act.

To doubt is a misfortune, but to seek when in doubt is an indispensable duty. So he who doubts and seeks not is at once unfortunate and unfair.