A scientist should be the happiest of men.

The great questions are those an intelligent child asks and, getting no answers, stops asking.

A scientist should be the happiest of men.

We are living in a world in which all wars are wars of defense.

We have to get rid of those nuclear weapons.

Faced with a new mutation in an organism, or a fundamental change in its living conditions, the biologist is frequently in no position whatever to predict its future prospects. He has to wait and see. For instance, the hairy mammoth seems to have been an admirable animal, intelligent and well-accoutered. Now that it is extinct, we try to understand why it failed. I doubt that any biologist thinks he could have predicted that failure. Fitness and survival are by nature estimates of past performance.

A physicist is an atom's way of knowing about atoms.