All human activity is prompted by desire.

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.

To expect a personality to survive the disintegration of the brain is like expecting a cricket club to survive when all of its members are dead.

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.

In the higher walks of politics the same sort of thing occurs. The statesman who has gradually concentrated all power within himself ... may have had anything but a public motive... The phrases which are customary on the platform and in the Party Press have gradually come to him to seem to express truths, and he mistakes the rhetoric of partisanship for a genuine analysis of motives... He retires from the world after the world has retired from him.

I am delighted to know that Principia Mathematica can now be done by machinery. . . I am quite willing to believe that anything in deductive logic can be done by machinery.

Men who allow their love of power to give them a distorted view of the world are to be found in every asylum: one man will think he is the Governor of the Bank of England, another will think he is the King, and yet another will think he is God. Highly similar delusions, if expressed by educated men in obscure language, lead to professorships of philosophy; and if expressed by emotional men in eloquent language, lead to dictatorships.