There is only one virtue, justice; only one duty, to be happy; only one corollary, not to overvalue life and not to fear death.

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.

The enjoyment of freedom which could be exercised without any motivation would be the real hallmark of a maniac.

Happiest are the people who give most happiness to others.

I am more affected by the attractions of virtue than by the deformities of vice; I turn gently away from the wicked and I fly to meet the good. If there is in a literary work, in a character, in a picture, in a statue, a beautiful spot, that is where my eyes rest; I see only that, I remember only that, all the rest is well-nigh forgotten. What becomes of me when the whole work is beautiful!

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.

A thing is not proved just because no one has ever questioned it. What has never been gone into impartially has never been properly gone into. Hence scepticism is the first step toward truth. It must be applied generally, because it is the touchstone.