What is called an acute knowledge of human nature is mostly nothing but the observer's own weaknesses reflected back from others.

Astronomy is perhaps the science whose discoveries owe least to chance, in which human understanding appears in its whole magnitude, and through which man can best learn how small he is.

We often have need of a profound philosophy to restore to our feelings their original state of innocence, to find our way out of the rubble of things alien to us, to begin to feel for ourselves and to speak ourselves, and I might almost say to exist ourselves.

One's first step in wisdom is to question everything - and one's last is to come to terms with everything.

God creates the animals, man creates himself.

Pain warns us not to exert our limbs to the point of breaking them. How much knowledge would we not need to recognize this by the exercise of mere reason.

He who is enamored of himself will at least have the advantage of being inconvenienced by few rivals.