How hollow is the heart of man, and how full of excrement!

This is what I see, and what troubles me. I look on all sides, and everywhere I see nothing but obscurity. Nature offers me nothing that is not a matter of doubt and disquiet.

Let man then contemplate the whole of nature in her full and grand majesty... No idea approaches it. We may enlarge our conceptions beyond all imaginable space; we only produce atoms in comparison with the reality of things. It is an infinite sphere, the center of which is everywhere, the circumference nowhere.

There are two equally dangerous extremes-to shut reason out, and to let nothing else in.

When we wish to correct with advantage, and to show another that he errs, we must notice from what side he views the matter, for on that side it is usually true.

We must learn our limits. We are all something, but none of us are everything.

The art of subversion, of revolution, is to dislodge established customs by probing down to their origins in order to show how they lack authority and justice.