Renown? I've already got more of it than those I respect, and will never have as much as those for whom I feel contempt.

Science had better not free the minds of men too much, before it has tamed their instincts.

It is not easy to imagine how little interested a scientist usually is in the work of any other, with the possible exception of the teacher who backs him or the student who honors him.

Never feel remorse for what you have thought about your wife; she has thought much worse things about you.

Think? Why think! We have computers to do that for us.

What scientist would not long to go on living, if only to see how the little truths he has brought to light will grow up?

Kill one man and you're a murderer, kill a million and you're a conqueror.