Nothing happens unless something moves.

God is subtle but he is not malicious.

Each makes this cosmos and its construction the pivot of his emotional life, in order to find in this way peace and security which he can not find in the narrow whirlpool of personal experience.

A new idea comes suddenly and in a rather intuitive way, but intuition is nothing but the outcome of earlier intellectual experience.

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

If you can't explain something simply, you don't know enough about it.

I think that only daring speculation can lead us further and not accumulation of facts.