Man, surrounded by facts, permitting himself no surprise, no intuitive flash, no great hypothesis, no risk, is in a locked cell. Ignorance cannot seal the mind and imagination more securely.

We come now to the question: what is a priori certain or necessary, respectively in geometry (doctrine of space) or its foundations? Formerly we thought everything; nowadays we think nothing. Already the distance-concept is logically arbitrary; there need be no things that correspond to it, even approximately.

In matters of truth and justice, there is no difference between large and small problems, for issues concerning the treatment of people are all the same.

But without deeper reflection one knows from daily life that one exists for other people--first of all for those upon whose smiles and well-being our own happiness is wholly dependent, and then for the many, unknown to us, to whose destinies we are bound by the ties of sympathy.

What interests me most is whether God could have made the world differently.

Don't become a seeker of success. Become a person of value.

Everybody acts not only under external compulsion but also in accordance with inner necessity.