It is a very grave mistake to think that the enjoyment of seeing and searching can be promoted by means of coercion and a sense of duty. To the contrary, I believe it would be possible to rob even a healthy beast of prey of its voraciousness, if it were possible, with the aid of a whip, to force the beast to devour continuously, even when not hungry.

I find it difficult to believe that I belong to such an idiotic, rotten species - the species that actually boasts of its freedom of will, heroism on command, senseless violence, and all of the loathsome nonsense that goes by the name of patriotism.

God does not care about our mathematical difficulties. He integrates empirically.

The number of natural hypothesis that can explain any given phenomena is infinite.

It is also a natural thing for a serious young man that he should form for himself as precise an idea as possible of the goal of his desires.

The religious geniuses of all ages have been distinguished by this kind of religious feeling, which knows no dogma and no God conceived in man's image; so that there can be no church whose central teachings are based on it. Hence it is precisely among the heretics of every age that we find men who were filled with this highest kind of religious feeling and were in many cases regarded by their contemporaries as atheists, sometimes also as saints. Looked at in this light, men like Democritus, Francis of Assisi, and Spinoza are closely akin to one another.

All religions, arts and sciences are branches of the same tree. All these aspirations are directed toward ennobling man's life, lifting it from the sphere of mere physical existence and leading the individual towards freedom.