William Kingdon Clifford quotes:

The harm which is done by credulity in a man is not confined to the fostering of a credulous character in others, and consequent support of false beliefs.

Namely, we have no right to believe a thing true because everybody says so unless there are good grounds for believing that some one person at least has the means of knowing what is true, and is speaking the truth so far as he knows it.

To consider only one other such witness: the followers of the Buddha have at least as much right to appeal to individual and social experience in support of the authority of the Eastern saviour.

If I steal money from any person, there may be no harm done from the mere transfer of possession; he may not feel the loss, or it may prevent him from using the money badly. But I cannot help doing this great wrong towards Man, that I make myself dishonest.

When an action is once done, it is right or wrong for ever; no accidental failure of its good or evil fruits can possibly alter that.

An atmosphere of beliefs and conceptions has been formed by the labours and struggles of our forefathers, which enables us to breathe amid the various and complex circumstances of our life.

To know all about anything is to know how to deal with it under all circumstances.

The danger to society is not merely that it should believe wrong things, though that is great enough; but that it should become credulous, and lose the habit of testing things and inquiring into them; for then it must sink back into savagery.

Every rustic who delivers in the village alehouse his slow, infrequent sentences, may help to kill or keep alive the fatal superstitions which clog his race.

No simplicity of mind, no obscurity of station, can escape the universal duty of questioning all that we believe.

In like manner, if I let myself believe anything on insufficient evidence, there may be no great harm done by the mere belief; it may be true after all, or I may never have occasion to exhibit it in outward acts.

This sense of power is the highest and best of pleasures when the belief on which it is founded is a true belief, and has been fairly earned by investigation.

There is no scientific discoverer, no poet, no painter, no musician, who will not tell you that he found ready made his discovery or poem or picture - that it came to him from outside, and that he did not consciously create it from within.

It is wrong always, everywhere, and for anyone, to believe anything upon insufficient evidence.

If a belief is not realized immediately in open deeds, it is stored up for the guidance of the future.

We may always depend on it that algebra, which cannot be translated into good English and sound common sense, is bad algebra.

To sum up: it is wrong always, everywhere, and for anyone, to believe anything upon insufficient evidence.

A little reflection will show us that every belief, even the simplest and most fundamental, goes beyond experience when regarded as a guide to our actions.

The rule which should guide us in such cases is simple and obvious enough: that the aggregate testimony of our neighbours is subject to the same conditions as the testimony of any one of them.

He who truly believes that which prompts him to an action has looked upon the action to lust after it, he has committed it already in his heart.

All our liberties are due to men who, when their conscience has compelled them, have broken the laws of the land.

An atom must be at least as complex as a grand piano.

If a man, holding a belief which he was taught in childhood or persuaded of afterwards, keeps down and pushes away any doubts which arise about it in his mind, purposely avoids the reading of books and the company of men that call in question or discuss it, and regards as impious those questions which cannot easily be asked without disturbing it - the life of that man is one long sin against mankind.

It cannot be doubted that theistic belief is a comfort and a solace to those who hold it, and that the loss of it is a very painful loss. It cannot be doubted, at least, by many of us in this generation, who either profess it now, or received it in our childhood and have parted from it since with such searching trouble as only cradle-faiths can cause. We have seen the spring sun shine out of an empty heaven, to light up a soulless earth; we have felt with utter loneliness that the Great Companion is dead.

Our lives our guided by that general conception of the course of things which has been created by society for social purposes.

Remember that [scientific thought] is the guide of action; that the truth which it arrives at is not that which we can ideally contemplate without error, but that which we may act upon without fear; and you cannot fail to see that scientific thought is not an accompaniment or condition of human progress, but human progress itself.

scientific thought does not mean thought about scientific subjects with long names. There are no scientific subjects. The subject of science is the human universe; that is to say, everything that is, or has been, or may be related to man.

The aim of scientific thought, then, is to apply past experience to new circumstances; the instrument is an observed uniformity in the course of events. By the use of this instrument it gives us information transcending our experience, it enables us to infer things that we have not seen from things that we have seen; and the evidence for the truth of that information depends on our supposing that the uniformity holds good beyond our experience.

The scientific discovery appears first as the hypothesis of an analogy; and science tends to become independent of the hypothesis.

There is one thing in the world more wicked than the desire to command, and that is the will to obey.

Thought is powerless, except it make something outside of itself: the thought which conquers the world is not contemplative but active.

We feel much happier and more secure when we think we know precisely what to do, no matter what happens, then when we have lost our way and do not know where to turn.