You see, Mademoiselle, I have experience, I know the world. To pass the time, why don't you ask every passenger to tell you his life's story? And if there is a single one among them who has never cursed his life, who has not often told himself that he was the unhappiest of men, then you may throw me overboard, headfirst!

Descartes constructed as noble a road of science, from the point at which he found geometry to that to which he carried it, as Newton himself did after him. ... He carried this spirit of geometry and invention into optics, which under him became a completely new art.

Poetry is the music of the soul, and, above all, of great and feeling souls.

The superfluous, a very necessary thing.

Earth is an insane asylum, to which the other planets deport their lunatics.

I was never ruined but twice: once when I lost a lawsuit, and once when I won one.

Liberty, then, about which so many volumes have been written is, when accurately defined, only the power of acting.