Life is a constant process of dying.

The greatest of follies is to sacrifice health for any other kind of happiness.

Of all the intellectual faculties, judgment is the last to mature. A child under the age of fifteen should confine its attention either to subjects like mathematics, in which errors of judgment are impossible, or to subjects in which they are not very dangerous, like languages, natural science, history, etc.

The real meaning of persona is a mask, such as actors were accustomed to wear on the ancient stage; and it is quite true that no one shows himself as he is, but wears his mask and plays his part. Indeed, the whole of our social arrangements may be likened to a perpetual comedy; and this is why a man who is worth anything finds society so insipid, while a blockhead is quite at home in it.

Anyone can squash a bug but all professors of this world couldn't build one.

However, for the man who studies to gain insight, books and studies are merely rungs of the ladder on which he climbs to the summit of knowledge. As soon as a rung has raised him up one step, he leaves it behind. On the other hand, the many who study in order to fill their memory do not use the rungs of the ladder for climbing, but take them off and load themselves with them to take away, rejoicing at the increasing weight of the burden. They remain below forever, because they bear what should have bourne them.

Man may have the most excellent judgment in all other matters, and yet go wrong in those which concern himself; because here the will comes in and deranges the intellect at once. Therefore let a man take counsel of a friend. A doctor can cure everyone but himself; if he falls ill, he sends for a colleague.