“It is amazing how much both happiness and efficiency can be increased by the cultivation of an orderly mind, which thinks about a matter adequately at the right time rather than inadequately at all times. When a difficult or worrying decision has to be reached, as soon as all the data are available, give the matter your best thought and make your decision; having made the decision, do not revise it unless some new fact comes to your knowledge. Nothing is so exhausting as indecision, and nothing is so futile.”

“The wise man thinks about his troubles only when there is some purpose in doing so; at other times he thinks about other things, or, if it is night, about nothing at all.”

“The methods of increasing the degree of truth in our beliefs are well known; they consist in hearing all sides, trying to ascertain all the relevant facts, controlling our own bias by discussion with people who have the opposite bias, and cultivating a readiness to discard any hypothesis which has proved inadequate.”

“I have been accused of a habit of changing my opinions. I am not myself in any degree ashamed of having changed my opinions. What physicist who was already active in 1900 would dream of boasting that his opinions had not changed during the last half century? In science men change their opinions when new knowledge becomes available; but philosophy in the minds of many is assimilated rather to theology than to science. The kind of philosophy that I value and have endeavoured to pursue is scientific, in the sense that there is some definite knowledge to be obtained and that new discoveries can make the admission of former error inevitable to any candid mind. For what I have said, whether early or late, I do not claim the kind of truth which theologians claim for their creeds. I claim only, at best, that the opinion expressed was a sensible one to hold at the time when it was expressed. I should be much surprised if subsequent research did not show that it needed to be modified. I hope, therefore, that whoever uses this dictionary will not suppose the remarks which it quotes to be intended as pontifical pronouncements, but only as the best I could do at the time towards the promotion of clear and accurate thinking. Clarity, above all, has been my aim.”

“To all the talented young men who wander about feeling that there is nothing in the world for them to do, I should say: 'Give up trying to write, and, instead, try not to write. Go out into the world; become a pirate, a king in Borneo, a labourer in Soviet Russia; give yourself an existence in which the satisfaction of elementary physical needs will occupy almost all your energies.' I do not recommend this course of action to everyone, but only to those who suffer from the disease which Mr Krutch diagnoses. I believe that, after some years of such an existence, the ex-intellectual will fin that in spite of is efforts he can no longer refrain from writing, and when this time comes his writing will not seem to him futile.”

“Nevertheless, when it is your lot to have to endure something that is (or seems to you) worse than the ordinary lot of mankind, Spinoza's principle of thinking about the whole, or at any rate about larger matters than your own grief, is a useful one. There are even times when it is comforting to reflect that human life, with all that is contains of evil and suffering, is an infinitesimal part of the life of the universe. Such reflections may not suffice to constitute a religion, but in a painful world they are a help towards sanity and an antidote to the paralysis of utter despair. - about Spinoza”

“When you come to look into this argument from design, it is a most astonishing thing that people can believe that this world, with all the things that are in it, with all its defects, should be the best that omnipotence and omniscience have been able to produce in millions of years. I really cannot believe it. Do you think that, if you were granted omnipotence and omniscience and millions of years in which to perfect your world, you could produce nothing better than the Ku Klux Klan or the Fascists? Moreover, if you accept the ordinary laws of science, you have to suppose that human life and life in general on this planet will die out in due course: it is a stage in the decay of the solar system; at a certain stage of decay you get the sort of conditions of temperature and so forth which are suitable to protoplasm, and there is life for a short time in the life of the whole solar system. You see in the moon the sort of thing to which the earth is tending -- something dead, cold, and lifeless.”