Every isolated passion, is, in isolation, insane; sanity may be defined as synthesis of insanities. Every dominant passion generates a dominant fear, the fear of its non-fulfillment. Every dominant fear generates a nightmare, sometimes in form of explicit and conscious fanaticism, sometimes in paralyzing timidity, sometimes in an unconscious or subconscious terror which finds expression only in dreams. The man who wishes to preserve sanity in a dangerous world should summon in his own mind a parliament of fears, in which each in turn is voted absurd by all the others.

Philosophy, from the earliest times, has made greater claims, and achieved fewer results, than any other branch of learning.

We are all prone to the malady of the introvert who with the manifold spectacle of the world spread out before him, turns away and gazes only upon the emptiness within.

A man's acts are partly determined by spontaneous impulse, partly by the conscious and unconscious effects of the various groups to which he belongs.

Work is of two kinds: first, altering the position of matter at or near the earth's surface relative to other matter; second, telling other people to do so.

As a philosopher, if I were speaking to a purely philosophic audience I should say that I ought to describe myself as an Agnostic, because I do not think that there is a conclusive argument by which one can prove that there is not a God. On the other hand, if I am to convey the right impression to the ordinary man in the street I think that I ought to say that I am an Atheist, because, when I say that I cannot prove that there is not a God, I ought to add equally that I cannot prove that there are not the Homeric gods.

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.