Whatever else there may be in our nature, responsibility toward truth is one of its attributes.

In any attempt to bridge the domains of experience belonging to the spiritual and physical sides of nature, time occupies the key position.

We used to think that if we knew one, we knew two, because one and one are two. We are finding that we must learn a great deal more about 'and'.

Every body continues in its state of rest or uniform motion in a straight line, except insofar as it doesn't.

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

The word reality frightens me.

Man is slightly nearer to the atom than to the star. ... From his central position man can survey the grandest works of Nature with the astronomer, or the minutest works with the physicist. ... [K]nowledge of the stars leads through the atom; and important knowledge of the atom has been reached through the stars.