I picture the vast realm of the sciences as an immense landscape scattered with patches of dark and light. The goal towards which we must work is either to extend the boundaries of the patches of light, or to increase their number. One of these tasks falls to the creative genius; the other requires a sort of sagacity combined with perfectionism.

If your little savage were left to himself and be allowed to retain all his ignorance, he would in time join the infant's reasoning to the grown man's passion, he would strangle his father and sleep with his mother.

The world is the house of the strong.

If you want me to believe in God, you must make me touch him.

Scepticism is the first step toward truth.

If you disturb the colors of the rainbow, the rainbow is no longer beautiful.

Philosophy is as far separated from impiety as religion is from fanaticism.