Generations to come will scarce believe that such a one as this ever in flesh and blood walked upon this earth. (said of Mahatma Gandhi)

All men are ignorant, just in different fields.

The most incomprehensible thing about the world is that it is comprehensible.

[Freud's] sense of reality is less clouded by wishful thinking than is the case with other people and [he combines] the qualities of critical judgment, earnestness and responsibility.

The ideals which have always shone before me and filled me with the joy of living are goodness, beauty, and truth.

Physical concepts are free creations of the human mind, and are not, however it may seem, uniquely determined by the external world.

We must learn the difficult lesson that the future of Mankind will only be tolerable when our course, in world affairs as in others, is based upon justice and law rather than the threat of naked power.