Fools have a habit of believing that everything written by a famous author is admirable. For my part I read only to please myself and like only what suits my taste.
It requires twenty years for a man to rise from the vegetable state in which he is within his mother's womb, and from the pure animal state which is the lot of his early childhood, to the state when the maturity of reason begins to appear. It has required thirty centuries to learn a little about his structure. It would need eternity to learn something about his soul. It takes an instant to kill him.
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.
I have wanted to kill myself a hundred times, but somehow I am still in love with life. This ridiculous weakness is perhaps one of our more stupid melancholy propensities, for is there anything more stupid than to be eager to go on carrying a burden which one would gladly throw away, to loathe one’s very being and yet to hold it fast, to fondle the snake that devours us until it has eaten our hearts away?
It is ourselves alone that make our days lucky or unlucky. Away, then, with a vain prejudice, the invention of the priesthood, which has been transmitted by our ancestors to an ignorant people.
Once your faith persuades you to believe what your intelligence declares absurd, beware, lest you likewise sacrifice your reason in the conduct of your life.