It is our knowledge - the things we are sure of - that makes the world go wrong and keeps us from seeing and learning.

The only thing worth having in an earthly existence is a sense of humor.

We know that there is no absolute knowledge, that there are only theories; but we forget this. The better educated we are, the harder we believe in axioms.

My father, the practical joker, did not care for practical jokes on himself; he did not encourage the practice in me.

My father made with me one serious mistake which I see parents about me making. He got himself somehow into the awkward position of an authority; I thought he knew and was right on everything - for a while.

The doctrine of Jesus is the most revolutionary propaganda that I have ever encountered.

It is possible to get an education at a university. It has been done; not often.