Experience has taught me a technique for dealing with such people [...] I counter the devotees of the Great Pyramid by adoration of the Sphinx; and the devotee of nuts by pointing out that hazelnuts and walnuts are as deleterious as other foods and only Brazil nuts should be tolerated. But when I was younger I had not yet acquired this technique, with the result that my contacts with cranks were sometimes alarming.

He will see himself and life and the world as truly as our human limitations will permit; realizing the brevity and minuteness of human life, he will realize also that in individual minds is concentrated whatever of value the known universe contains.

It is not by delusion, however exalted, that mankind can prosper, but only by unswerving courage in the pursuit of truth.

A marriage is likely to be called happy if neither party ever expected to get much happiness out of it.

Affection cannot be created; it can only be liberated.

The wise man will be as happy as circumstances permit, and if he finds the contemplation of the universe painful beyond a point, he will contemplate something else instead.

Philosophy arises from an unusually obstinate attempt to arrive at real knowledge. What passes for knowledge in ordinary life suffers from three defects: it is cocksure, vague and self-contradictory. The first step towards philosophy consists in becoming aware of these defects, not in order to rest content with a lazy scepticism, but in order to substitute an amended kind of knowledge which shall be tentative, precise and self-consistent.