There is no hope for any speculation that does not look absurd at first glance.

Of course I don't believe in it [pointing to horseshoe on his office wall]. But I understand that it brings you luck whether you believe in it or not.

Sometimes the child in one behaves a certain way and the rest of oneself follows behind, slowly shaking its head.

Anyone who can contemplate quantum mechanics without getting dizzy hasn't understood it.

In our description of nature the purpose is not to disclose the real essence of the phenomena but only to track down, so far as it is possible, relations between the manifold aspects of our experience.

The best weapon of a dictatorship is secrecy, but the best weapon of a democracy should be the weapon of openness.

An expert is a man who has made all the mistakes which can be made, in a narrow field.