Every animal leaves traces of what it was; man alone leaves traces of what he created.
Knowledge is an unending adventure at the edge of uncertainty.
The values by which we are to survive are not rules for just and unjust conduct, but are those deeper illuminations in whose light justice and injustice, good and evil, means and ends are seen in fearful sharpness of outline.
Science has nothing to be ashamed of even in the ruins of Nagasaki. The shame is theirs who appeal to other values than the human imaginative values which science has evolved.
It is important that students bring a certain ragamuffin, barefoot irreverence to their studies; they are not here to worship what is known, but to question it.
The wish to hurt, the momentary intoxication with pain, is the loophole through which the pervert climbs into the minds of ordinary men.