Gradually the conviction gained recognition that all knowledge about things is exclusively a working-over of the raw material furnished by the senses. ... Galileo and Hume first upheld this principle with full clarity and decisiveness.

Be kind to people who are different from you.

The ideals which have lighted my way, and time after time have given me new courage to face life cheerfully, have been Kindness, Beauty, and Truth. Without the sense of kinship with men of like mind, without the occupation with the objective world, the eternally unattainable in the field of art and scientific endeavors, life would have seemed to the empty. The trite objects of human efforts — possessions, outward success, luxury—have always seemed to me contemptible.

I am convinced that some political and social activities and practices of the Catholic organizations are detrimental and even dangerous for the community as a whole, here and everywhere. I mention here only the fight against birth control at a time when overpopulation in various countries has become a serious threat to the health of people and a grave obstacle to any attempt to organize peace on this planet.

A religious person is devout in the sense that he has no doubt about the significance of those superpersonal objects and goals which neither require nor are capable of rational foundation

One scientific epoch ended and another began with James Clerk Maxwell.

I do not believe in the God of theology who rewards good and punishes evil.