Never try to discourage thinking, for you are sure to succeed.

Mathematics may be defined as the subject in which we never know what we are talking about, nor whether what we are saying is true.

The satisfaction to be derived from success in a great constructive enterprise is one of the most massive that life has to offer.

The true spirit of delight, the exaltation, the sense of being more than Man, which is the touchstone of the highest excellence, is to be found in mathematics as surely as poetry.

Happiness is not best achieved by those who seek it directly.

No satisfaction based upon self-deception is solid, and however unpleasant the truth may be, it is better to face it once and for all, to get used to it, and to proceed to build your life in accordance with it.

The most essential characteristic of scientific technique is that it proceeds from experiment, not from tradition. The experimental habit of mind is a difficult one for most people to maintain; indeed, the science of one generation has already become the tradition of the next