"We are all afraid for our confidence, for the future, for the world. That is the nature of the human imagination. Yet every man, every civilization, has gone forward because of its engagement with what it has set itself to do."

"Every animal leaves traces of what it was; man alone leaves traces of what he created."

"The wish to hurt, the momentary intoxication with pain, is the loophole through which the pervert climbs into the minds of ordinary men."

"The most wonderful discovery made by scientists is science itself."

"Political ideology can corrupt the mind, and science."

"Living here on Earth, we breathe the rhythms of a universe that extends infinitely above us. When resonant harmonies arise between this vast outer cosmos and the inner human cosmos, poetry is born."

"You see, I became kind of a drop-out in science after I came back to America."

"Whatever universe a professor believes in must at any rate be a universe that lends itself to lengthy discourse. A universe definable in two sentences is something for which the professorial intellect has no use. No faith in anything of that cheap kind!"