I write these remarks with one great hope, that of arousing controversy. It is really a singular matter that amid all the talk of the great work of physical science and its alleged victory over religious dogmatism, no one has noticed what the greatest of all the triumphs of science really was. It was a discovery far greater than that of evolution. It was the discovery, not of a fact, but of a method, the mother of innumerable facts. That method is, of course, what is known in scientific theory as the method of the hypothesis. It can be most clearly and simply conveyed in common language by saying that it is the principle that the best way to see if a coat fits a man is not to measure both of them, but to try it on. It is the replacing of the very slow, logical method of accumulating, point by point, an absolute proof by a rapid, experimental and imaginative method which gives us, long before we can get absolute proof, a very good working belief. I hear, let us say, of a certain theory about the universe. As a trial, I assume it to be true; then, if I discover with a start that, once assumed, it explains the boots on my feet and the nose on my face, that my umbrella has a new and radiant meaning, that my front door suddenly explains itself, that truths about my cat and dog and wife and hat and sideboard crowd upon me all day and everyday, I believe that theory and go on believing it more and more.
On the other hand, if the theory be not true, I may be perfectly certain that ten minutes after I have experimentally assumed it, I shall break my shins over some contradiction. We have buttoned the coat round the world (that rotund and patient old gentleman) and it has split down the back. It is surely quite obvious that this is the method on which we base all our real beliefs and that on this, above all, we base our belief in evolution. Of the thousands of brilliant and elegant persons like ourselves who believe roughly in the Darwinian doctrine, how many are there who know which fossil or skeleton, which parrot's tail or which cuttle-fish's stomach, is really believed to be the conclusive example and absolute datum of natural selection? We know scarcely anything of the Darwinian facts that lead to conversion. What we know is much more important: the Darwinian facts that come after conversion. What we know, to use a higher language, are the fruits of the spirit. We know that with this idea once inside our heads a million things become transparent as if a lamp were lit behind them: we see the thing in the dog in the street, in the pear on the wall, in the book of history we are reading, in the baby in the perambulator and in the last news from Borneo. And the fulfilments pour in upon us in so natural and continual a cataract that at last is reached that paradox of the condition which is called belief. We have seen so many evidences of the theory that we have forgotten them all. The theory is so clear to us that we can scarcely even defend it, If we walked up to the nearest rationalist we know and asked him to prove evolution, he would be dazed, like a man asked to defend justice.
Now it ought to be clearly stated at this stage of philosophical development that it is most emphatically by this method of the successful hypothesis, of the theory that justifies itself, that so large a number of the young in this generation have returned to a certain doctrine of the spiritual. What this doctrine is it may be right to state as baldly and as briefly as possible; it is the view that the world, closely examined, does point with an extreme suggestiveness to the existence of a spiritual world, of a world of agencies not apparently produced by matter, capable to some extent of controlling and inspiring, capable to some extent of being known. It ought, I say, to be plainly stated that numbers of us have returned to this belief; and that we have returned to it, not because of this argument or that argument, but because the theory, when it is adopted, works out everywhere; because the coat, when it is tried on, fits in every crease. It ought to be stated because the old rationalists are rightly indignant with us, in so far as they fancy that we base such a tremendous doctrine on a few desperate quibbles; in so far as they fancy, as they do, that we are hanging on to religion by sticks and straws.... The return to the spiritual theory rests on none of these things. It rests, like the movement towards evolution, on the fact that the thing works out. We put on the theory like a magic hat and history becomes translucent like a house of glass.
Let us begin at the beginning. A startling and sensational event occurred recently; I allude to the emergence of the creature called man. It is a recent event, cosmically considered; it is, comparatively speaking, only a little too old to have been headlined in the evening papers. The newness, suddenness and utter uniqueness of the rise of man reminds one of Japan in the East; only it is more so.... There may be a hundred explanations of this. No sane man would say that it involved a spiritual deduction. But it fits in with it, and fits in with it very well, to suppose that there is another atmosphere of life besides the animal and that this spiritual world irrupted in some way into that creature at the moment. The phenomenon does not prove Religion, but religion explains the Phenomenon. The Phenomenon is quite as solitary as the Incarnation. It can be explained by saying that in a sense it was the Incarnation. Then we go on. There is one thing which the whole human race, without any exception at all, attests. From the dimmest ages and lands, wherever the seed of man is found, it declares this that such an irruption did take place in the beginning, that they or their fathers have had dealings with a darker or more wonderful being. If human evidence means anything at all, this is perhaps the only thing on which we have overwhelming evidence.
We have nearly overwhelming human witness to the necessity of morality; we have quite overwhelming human witness to the reality of the spiritual life. We are ready enough to quote the evidence of all mankind in support of police regulations or the data of ethics; but we think mankind must be talking nonsense when, with one universal shout it cries out to this thing which is older than sin. That Marcus Aurelius and the Red Indians, that Hindu sages and Italian brigands and Mr Spurgeon and Sir William Crookes should all by various roads come to this conclusion, this is an important thing. A more important thing still is that this belief in spirit, so far from being a morbid thing, is held by almost all people who are physically strong and live in the open air. Powerful peasants and farmers six feet high all believe in fairies. Rationalism is a disease of the towns, like the housing problem. All this is, of course, only suggestive, but it is very suggestive. The Phenomenon does not prove Religion; but Religion explains the Phenomenon.... We have not returned to the spiritual theory because of this or that triviality--because of a justification of the Fourth Gospel or a rap on the table. We have returned to it because, by the rejection of rationalism, the world becomes suddenly rational.