The science of pure mathematics, in its modern developments, may claim to be the most original creation of the human spirit.

We think in generalities, but we live in detail.

Imagination is not to be divorced from the facts. It is a way of illuminating the facts.

The point about zero is that we do not need to use it in the operation of daily life. No one goes out to buy zero fish.

I regret that it has been necessary for me in this lecture to administer a large dose of four-dimensional geometry. I do not apologize, because I am really not responsible for the fact that nature in its most fundamental aspect is four-dimensional. Things are what they are.

The learned tradition is not concerned with truth, but with the learned adjustment of learned statements of antecedent learned people.

Philosophy is the product of wonder.