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.

The first and most important necessity is the creation of a modus vivendi with the Arab people.

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.

I see in Nature a magnificent structure... that must fill a thinking person with a feeling of humility.

It is best, it seems to me, to separate one's inner striving from one's trade as far as possible. It is not good when one's daily break is tied to God's special blessing.

What good is a reputation not put to good use.

Politics is a pendulum whose swings between anarchy and tyranny are fueled by perennially rejuvenated illusions.