All things must be examined, debated, investigated without exception and without regard for anyone's feelings.

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

One must be oneself very little of a philosopher not to feel that the finest privilege of our reason consists in not believing in anything by the impulsion of a blind and mechanical instinct, and that it is to dishonour reason to put it in bonds as the Chaldeans did. Man is born to think for himself.

Posterity for the philosopher is what the other world is for the religious man.

It is raining bombs on the house of the Lord. I go in fear and trembling lest one of these terrible bombers gets into difficulties.

Happiest are the people who give most happiness to others.

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.