Self-love is an instrument useful but dangerous; it often wounds the hand which makes use of it, and seldom does good without doing harm.

One may live tranquilly in a dungeon; but does life consist in living quietly?

This dog, which, although no beauty, was of an uncommon breed, I had made my friend and companion; and it certainly deserved the name better than the majority of those who had assumed it.

People in their natural state are basically good. But this natural innocence,however, is corrupted by the evils of society.

Gratitude is a duty which ought to be paid, but which none have a right to expect.

The abuse of books kills science. Believing that we know what we have read, we believe that we can dispense with learning it.

Great men never make bad use of their superiority. They see it and feel it and are not less modest. The more they have, the more they know their own deficiencies.