I believe in Spinoza's God, who reveals Himself in the lawful harmony of the world, not in a God who concerns Himself with the fate and the doings of mankind... to Rabbi Herbert Goldstein (1929)

Any fool can know. The point is to understand.

It's not that I'm so smart.

Thinking is to man what flying is to birds. Don’t follow the example of a chicken when you could be a lark.

The idea of a personal God is quite alien to me and seems even naïve.

If I had only one hour to save the world, I would spend fifty-five minutes defining the problem, and only five minutes finding the solution.

You can never solve a problem with the same kind of thinking that created the problem in the first place.