“A philosopher who uses his professional competence for anything other except a disinterested search for truth is guilty of a kind of treachery.”

“It seems to me a fundamental dishonesty, and a fundamental treachery to intellectual integrity to hold a belief because you think it's useful and not because you think it's true.”

“It might seem that the empirical philosopher is the slave of his material, but that the pure mathematician, like the musician, is a free creator of his world of ordered beauty.”

“A good social system is not to be secured by making people unselfish, but, by making their own vital impulses fit in with other peoples. This is feasible. Those who have produced stoic philosophies have all had enough to eat and drink.I feel I shall find the truth on my deathbed and be surrounded by people too stupid to understand—fussing about medicines instead of searching for wisdom.I hate being all tidy like a book in a library where nobody reads – prison is horribly like that.”

“Philosophy, for Plato, is a kind of vision, the 'vision of truth' ... Everyone who has done any kind of creative work has experienced, in a greater or less degree, the state of mind in which, after long labour, truth or beauty appears, or seems to appear, in a sudden glory – it may only be about some small matter, or it may be about the universe ... I think most of the best creative work, in art, in science, in literature, and in philosophy, has been the result of such a moment.”

“Morality in sexual relations, when it is free from superstition, consists essentially in respect for the other person, and unwillingness to use that person solely as a means of personal gratification, without regard to his or her desires.”

“We shall be compelled to renounce the hope of finding philosophical proofs of religious beliefs. ...Hence, once more, the value of philosophy must not depend upon any supposed body of definitely ascertainable knowledge to be acquired by those who study it.”