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

“An expert is a person who has made all the mistakes that can be made in a very narrow field.”

“Everything we call real is made of things that cannot be regarded as real.”

“The very nature of the quantum theory ... forces us to regard the space-time coordination and the claim of causality, the union of which characterizes the classical theories, as complementary but exclusive features of the description, symbolizing the idealization of observation and description, respectively.”

“We are all agreed that your theory is crazy. The question which divides us is whether it is crazy enough to have a chance of being correct. My own feeling is that it is not crazy enough.”

“Prediction is very difficult, especially about the future.”

“The meaning of life consists in the fact that it makes no sense to say that life has no meaning.”