If you're certain, you're certainly wrong, because nothing deserves certainty.

Power, like vanity, is insatiable. Nothing short of omnipotence could satisfy it completely. And as it is especially the vice of energetic men, the causal efficacy of love of power is out of all proportion to its frequency. It is, indeed, by far the strongest motive in the lives of important men. Love of power is greatly increased by the experience of power, and this applies to petty power as well as to that of potentates.

Most of us are not neutral in feeling, but, as human beings, we have to remember that, if the issues between East and West are to be decided in any manner that can give any possible satisfaction to anybody, whether Communist or anti-Communist, whether Asian or European or American, whether White or Black, then these issues must not be decided by war. We should wish this to be understood, both in the East and in the West.

I observe that a very large portion of the human race does not believe in God and suffers no visible punishment in consequence. And if there were a God, I think it very unlikely that he would have such an uneasy vanity as to be offended by those who doubt his existence.

All sources of energy upon which industry depends are wasted when they are employed; and industry is expending them at a continually increasing rate. Already coal has been largely replaced by oil, and oil is being used up so fast that East and West alike conceive it necessary to their own prosperity to destroy the industry of the other. And what is true of oil is equally true of other natural resources. Every day, many square miles of forest are turned into newspaper, but there is no known process by which newspaper can be turned into forest. You will say that this need not worry us, since newspapers will be replaced by radio, but radio requires electricity, electricity requires power, and power depends upon raw materials.

There was once a millionaire who bought an infinite number of pairs of shoes and, whenever he bought a pair of shoes, he also bought a pair of socks. We can make a selection choosing one out of each pair of shoes, because we can choose always the right shoe or always the left shoe. Thus, so far as the shoes are concerned, selections exist. But, as regards the socks, where there is no distinction of right and left, we cannot use this rule of selection.

Man is a credulous animal, and must believe something; in the absence of good grounds for belief, he will be satisfied with bad ones.

There is something feeble and a little contemptible about a man who cannot face the perils of life without the help of comfortable myths. Almost inevitably some part of him is aware that they are myths and that he believes them only because they are comforting. But he dare not face this thought! Moreover, since he is aware, however dimly, that his opinions are not rational, he becomes furious when they are disputed.

I resolved from the beginning of my quest that I would not be misled by sentiment and desire into beliefs for which there was no good evidence.

If the Russians still adhered to the Greek Orthodox religion, if they had instituted parliamentary government, and if they had a completely free press which daily vituperated us, then - provided they still had armed forces as powerful as they have now - we should still hate them if they gave us ground for thinking them hostile.

The second matter in which Mill's principles condemn existing legislation is homosexuality. If two adults voluntarily enter into such a relation, this is a matter which concerns them only, and in which, therefore, the community ought not to intervene. If it were still believed, as it once was, that the toleration of such behavior would expose the community to the fate of Sodom and Gomorrah, the community would have every right to intervene. But it does not acquire a right to intervene merely on the ground that such conduct is thought wicked. The criminal law may rightly be invoked to prevent violence or fraud inflicted upon unwilling victims, but it ought not to be invoked when whatever damage there may be is suffered only by the agents-always assuming that the agents are adults.

When I was a boy, I had a clock with a pendulum that could be lifted off. I found that the clock went very much faster without the pendulum. If the main purpose of a clock is to go, the clock was the better for losing its pendulum. True, it could no longer tell the time, but that did not matter if one could teach oneself to be indifferent to the passage of time. The linguistic philosophy which cares only about language and not about the world, is like the boy who preferred the clock without the pendulum because, although it no longer told the time, it went more easily than before and at a more exhilarating pace.

Some part of life - perhaps the most important part - must be left to the spontaneous action of individual impulse, for where all is system there will be mental and spiritual death.

I find that the whiter my hair becomes the more ready people are to believe what I say.

The pursuit of knowledge is, I think, mainly actuated by love of power. And so are all advances in scientific technique. In politics, also, a reformer may have just as strong a love of power as a despot. It would be a complete mistake to decry love of power altogether as a motive. Whether you will be led by this motive to actions which are useful, or to actions which are pernicious, depends upon the social system, and upon your capacities.

There lies before us, if we choose, continual progress in happiness, knowledge, and wisdom. Shall we, instead, choose death, because we cannot forget our quarrels? We appeal as human beings to human beings: Remember your humanity, and forget the rest. If you can do so, the way lies open to a new Paradise; if you cannot, there lies before you the risk of universal death.

I have always thought respectable people scoundrels, and I look anxiously at my face every morning for signs of my becoming a scoundrel.

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.

What is serious about excitement is that so many of its forms are destructive. It is destructive in those who cannot resist excess in alcohol or gambling. It is destructive when it takes the form of mob violence. And above all it is destructive when it leads to war. It is so deep a need that it will find harmful outlets of this kind unless innocent outlets are at hand. There are such innocent outlets at present in sport, and in politics so long as it is kept within constitutional bounds. But these are not sufficient, especially as the kind of politics that is most exciting is also the kind that does most harm. Civilized life has grown altogether too tame, and, if it is to be stable, it must provide harmless outlets for the impulses which our remote ancestors satisfied in hunting.

When I was a child the atmosphere in the house was one of puritan piety and austerity. There were family prayers at eight o'clock every morning. Although there were eight servants, food was always of Spartan simplicity, and even what there was, if it was at all nice, was considered too good for children. For instance, if there was apple tart and rice pudding, I was only allowed the rice pudding. Cold baths all the year round were insisted upon, and I had to practice the piano from seven-thirty to eight every morning although the fires were not yet lit. My grandmother never allowed herself to sit in an armchair until the evening. Alcohol and tobacco were viewed with disfavor although stern convention compelled them to serve a little wine to guests. Only virtue was prized, virtue at the expense of intellect, health, happiness, and every mundane good.

There is no need to worry about mere size. We do not necessarily respect a fat man more than a thin man. Sir Isaac Newton was very much smaller than a hippopotamus, but we do not on that account value him less.

The criminal law has, from the point of view of thwarted virtue, the merit of allowing an outlet for those impulses of aggression which cowardice, disguised as morality, restrains in their more spontaneous forms. War has the same merit. You must not kill you neighbor, whom perhaps you genuinely hate, but by a little propaganda this hate can be transferred to some foreign nation, against whom all your murderous impulses become patriotic heroism.

I must before I die, find some way to say the essential thing that is in me, that I have never said yet - a thing that is not love or hate or pity or scorn, but the very breath of life, fierce and coming from far away, bringing into human life the vastness and fearful passionless force of non-human things...

Man differs from other animals in one very important respect, and that is that he has some desires which are, so to speak, infinite, which can never be fully gratified, and which would keep him restless even in Paradise. The boa constrictor, when he has had an adequate meal, goes to sleep, and does not wake until he needs another meal. Human beings, for the most part, are not like this.

The world is full of conflicts; and, overshadowing all minor conflicts, the titanic struggle between Communism and anti-Communism. Almost everybody who is politically conscious has strong feelings about one or more of these issues; but we want you, if you can, to set aside such feelings and consider yourselves only as members of a biological species which has had a remarkable history, and whose disappearance none of us can desire. We shall try to say no single word which should appeal to one group rather than to another. All, equally, are in peril, and, if the peril is understood, there is hope that they may collectively avert it.

Politics is concerned with herds rather than with individuals, and the passions which are important in politics are, therefore, those in which the various members of a given herd can feel alike.

The conviction that it is important to believe this or that, even if a free inquiry would not support the belief, is one which is common to almost all religions and which inspires all systems of state education. The consequence is that the minds of the young are stunted and are filled with fanatical hostility both to those who have other fanaticisms, and, even more virulently, to those who object to all fanaticisms.

A man might say, with enough truth to justify a joke: "Science is what we know, and philosophy is what we don't know." But it should be added that philosophical speculation as to what we do not yet know has shown itself a valuable preliminary to exact scientific knowledge.

Suppose atomic bombs had reduced the population of the world to one brother and one sister, should they let the human race die out? I do not know the answer, but I do not think it can be in the affirmative merely on the ground that incest is wicked.