It is sometimes maintained that racial mixture is biologically undesirable. There is no evidence whatever for this view. Nor is there, apparently, any reason to think that Negroes are congenitally less intelligent than white people, but as to that it will be difficult to judge until they have equal scope and equally good social conditions.

Some modern philosophers have gone so far as to say that words should never be confronted with facts but should live in a pure, autonomous world where they are compared only with other words. When you say, 'the cat is a carnivorous animal,' you do not mean that actual cats eat actual meat, but only that in zoology books the cat is classified among carnivora. These authors tell us that the attempt to confront language with fact is 'metaphysics' and is on this ground to be condemned. This is one of those views which are so absurd that only very learned men could possibly adopt them.

Neither a man nor a crowd nor a nation can be trusted to act humanely or to think sanely under the influence of a great fear.

If you think that your belief is based upon reason, you will support it by argument, rather than by persecution, and will abandon it if the argument goes against you. But if your belief is based on faith, you will realize that argument is useless, and will therefore resort to force either in the form of persecution or by stunting and distorting the minds of the young in what is called "education". This last is particularly dastardly, since it takes advantage of the defencelessness of immature minds. Unfortunately it is practiced in greater or less degree in the schools of every civilised country.

Truth is a shining goddess, always veiled, always distant, never wholly approachable, but worthy of all the devotion of which the human spirit is capable.

I do not think it can be questioned that sympathy is a genuine motive, and that some people at some times are made somewhat uncomfortable by the sufferings of some other people. It is sympathy that has produced the many humanitarian advances of the last hundred years. We are shocked when we hear stories of the ill-treatment of lunatics, and there are now quite a number of asylums in which they are not ill-treated. Prisoners in Western countries are not supposed to be tortured, and when they are, there is an outcry if the facts are discovered. We do not approve of treating orphans as they are treated in Oliver Twist.

In fact, contempt for happiness is usually contempt for other people's happiness, and is an elegant disguise for hatred of the human race.

Change is one thing, progress is another.

Diet, injections, and injunctions will combine, from a very early age, to produce the sort of character and the sort of beliefs that the authorities consider desirable, and any serious criticism of the powers that be will become psychologically impossible. Even if all are miserable, all will believe themselves happy, because the government will tell them that they are so.

The state is primarily an organization for killing foreigners.

The politician may change sides so frequently as to find himself always in the majority, but most politicians have a preference for one party to the other, and subordinate their love of power to this preference.

We invite this Congress, and through it the scientists of the world and the general public, to subscribe to the following resolution: "In view of the fact that in any future world war nuclear weapons will certainly be employed, and that such weapons threaten the continued existence of mankind, we urge the governments of the world to realize, and to acknowledge publicly, that their purpose cannot be furthered by a world war, and we urge them, consequently, to find peaceful means for the settlement of all matters of dispute between them".

Thank you for your letter and for the enclosure which I return herewith. I have been wondering whether there is any means of preventing the confusion between you and me, and I half-thought that we might write a joint letter to The Times in the following terms: Sir, To prevent the continuation of confusions which frequently occur, we beg to state that neither of us is the other. Do you think this would be a good plan?

Our great democracies still tend to think that a stupid man is more likely to be honest than a clever man, and our politicians take advantage of this prejudice by pretending to be even more stupid than nature made them.

I do not think it possible to get anywhere if we start from scepticism. We must start from a broad acceptance of whatever seems to be knowledge and is not rejected for some specific reason.

All human activity is prompted by desire. There is a wholly fallacious theory advanced by some earnest moralists to the effect that it is possible to resist desire in the interests of duty and moral principle. I say this is fallacious, not because no man ever acts from a sense of duty, but because duty has no hold on him unless he desires to be dutiful. If you wish to know what men will do, you must know not only, or principally, their material circumstances, but rather the whole system of their desires with their relative strengths.

We are speaking on this occasion, not as members of this or that nation, continent, or creed, but as human beings, members of the species Man, whose continued existence is in doubt.

Perhaps the best hope for the future of mankind is that ways will be found of increasing the scope and intensity of sympathy.

The harm that is done by a religion is of two sorts, the one depending on the kind of belief which it is thought ought to be given to it, and the other upon the particular tenets believed. As regards the kind of belief: it is thought virtuous to have faith-that is to say, to have a conviction which cannot be shaken by contrary evidence. Or, if contrary evidence might induce doubt, it is held that contrary evidence must be suppressed.

The essence of the Liberal outlook lies not in what opinions are held, but in how they are held: instead of being held dogmatically, they are held tentatively, and with a consciousness that new evidence may at any moment lead to their abandonment.

If throughout your life you abstain from murder, theft, fornication, perjury, blasphemy, and disrespect toward your parents, your church, and your king, you are conventionally held to deserve moral admiration even if you have never done a single kind or generous or useful action. This very inadequate notion of virtue is an outcome of taboo morality, and has done untold harm.

You, your families, your friends and your countries are to be exterminated by the common decision of a few brutal but powerful men. To please these men, all the private affections, all the public hopes, all that has been achieved in art, and knowledge and thought and all that might be achieved hereafter is to be wiped out forever. Our ruined lifeless planet will continue for countless ages to circle aimlessly round the sun unredeemed by the joys and loves, the occasional wisdom and the power to create beauty which have given value to human life.

Two men who differ as to the ends of life cannot hope to agree about education.

Whatever we know without inference is mental.

Obscenity is whatever happens to shock some elderly and ignorant magistrate.

An individual may perceive a way of life, or a method of social organisation, by which more of the desires of mankind could be satisfied than under the existing method. If he perceives truly, and can persuade men to adopt his reform, he is justified. Without rebellion, mankind would stagnate, and injustice would be irremediable.

Science may set limits to knowledge, but should not set limits to imagination.

There is much pleasure to be gained from useless knowledge.

I am ashamed of belonging to the species Homo Sapiens...You & I may be thankful to have lived in happier times - you more than I, because you have no children.

It is said (I do not know with what truth) that a certain Hindu thinker believed the earth to rest upon an elephant. When asked what the elephant rested upon, he replied that it rested upon a tortoise. When asked what the tortoise rested upon, he said, "I am tired of this. Suppose we change the subject." This illustrates the unsatisfactory character of the First-Cause argument.

Most people, at a crisis, feel more loyalty to their nation than to their class.

A life without adventure is likely to be unsatisfying, but a life in which adventure is allowed to take whatever form it will is sure to be short.

The secret of happiness is to face the fact that the world is horrible, horrible, horrible.

The observer, when he seems to himself to be observing a stone, is really, if physics is to be believed, observing the effects of the stone upon himself.

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 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.

Every man would like to be God, if it were possible; some few find it difficult to admit the impossibility.

Probably in time physiologists will be able to make nerves connecting the bodies of different people; this will have the advantage that we shall be able to feel another man's tooth aching.

Cock-sure certainty is the source of much that is worst in our present world, and it is something of which the contemplation of history ought to cure us, not only or chiefly because there were wise men in the past, but because so much that was thought wisdom turned out to be folly - which suggests that much of our own supposed wisdom is no better. I do not mean to maintain that we should lapse into a lazy scepticism. We should hold our beliefs, and hold them strongly. Nothing great is achieved without passion, but underneath the passion there should always be that large impersonal survey which sets limits to actions that our passions inspire.

The love of power is a part of human nature, but power-philosophies are, in a certain precise sense, insane. The existence of the external world, both that of matter and of other human beings, is a datum, which may be humiliating to a certain kind of pride, but can only be denied by a madman. 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 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 in philosophy; and if expressed by emotional men in eloquent language, lead to dictatorships. Certified lunatics are shut up because of the proneness to violence when their pretensions are questioned; the uncertified variety are given control of powerful armies, and can inflict death and disaster upon all sane men within their reach.

A stupid man's report of what a clever man says is never accurate, because he unconsciously translates what he hears into something that he can understand.

For my part, while I am as convinced a Socialist as the most ardent Marxian, I do not regard Socialism as a gospel of proletarian revenge, nor even, primarily, as a means of securing economic justice. I regard it primarily as an adjustment to machine production demanded by considerations of common sense, and calculated to increase the happiness, not only of proletarians, but of all except a tiny minority of the human race.

Men tend to have the beliefs that suit their passions. Cruel men believe in a cruel God, and use their belief to excuse their cruelty. Only kindly men believe in a kindly God, and they would be kindly in any case.

People will tell us that without the consolations of religion they would be intolerably unhappy. So far as this is true, it is a coward's argument. Nobody but a coward would consciously choose to live in a fool's paradise. When a man suspects his wife of infidelity, he is not thought the better of for shutting his eyes to the evidence. And I cannot see why ignoring evidence should be contemptible in one case and admirable in the other.

We thus have a kind of see-saw: first, pure persuasion leading to the conversion of a minority; then force exerted to secure that the rest of the community shall be exposed to the right propaganda; and finally a genuine belief on the part of the great majority, which makes the use of force again unnecessary.

Too little liberty brings stagnation, and too much brings chaos.

If the Communists conquered the world, it would be very unpleasant for a while, but not forever. But if the human race is wiped out, that is the end.

To understand the actual world as it is, not as we should wish it to be, is the beginning of wisdom.

Science seems to be at war with itself.... Naive realism leads to physics, and physics, if true, shows naive realism to be false. Therefore naive realism, if true, is false; therefore it is false.

When one admits that nothing is certain one must, I think, also admit that some things are much more nearly certain than others. It is much more nearly certain that we are assembled here tonight than it is that this or that political party is in the right. Certainly there are degrees of certainty, and one should be very careful to emphasize that fact, because otherwise one is landed in an utter skepticism, and complete skepticism would, of course, be totally barren and completely useless.

The fundamental concept in social science is Power, in the same sense in which Energy is the fundamental concept in physics.