I cannot conceive of a God who rewards and punishes his [sic] creatures, or has a will of the type of which we are conscious ourselves.

[Asked about a book in which 100 Nazi professors charged him with scientific error.] Were I wrong, one professor would have been quite enough.

Out of complexity, find simplicity!

The world as we see it is only the world as we see it. Others may see it differently.

Everything that is really great and inspiring is created by the individual who can labor in freedom.

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

The daily struggle does not arise from a purpose or a program, but from an immediate need.