Don't believe the results of experiments until they're confirmed by theory.

So far as physics is concerned, time's arrow is a property of entropy alone.

We have found that where science has progressed the farthest, the mind has but regained from nature that which the mind put into nature.

Philosophically, the notion of a beginning of the present order of Nature is repugnant to me ... I should like to find a genuine loophole.

I ask you to look both ways. For the road to a knowledge of the stars leads through the atom; and important knowledge of the atom has been reached through the stars.

Who will observe the observers?

The pursuit of truth in science transcends national boundaries. It takes us beyond hatred and anger and fear. It is the best of us.