We must not only learn to tolerate our differences. We must welcome them as the richness and diversity which can lead to true intelligence.

The wonder of nature does not become smaller because one cannot measure it by the standards of human moral and human aims.

Everybody acts not only under external compulsion but also in accordance with inner necessity.

I do not like to state an opinion on a matter unless I know the precise facts.

From a certain temperature on, the molecules 'condense' without attractive forces; that is, they accumulate at zero velocity. The theory is pretty, but is there some truth in it.

It is best, it seems to me, to separate one's inner striving from one's trade as far as possible. It is not good when one's daily break is tied to God's special blessing.

There is no logical way to the discovery of these elemental laws. There is only the way of intuition, which is helped by a feeling for the order lying behind the appearance.