The real trouble with this world of ours is not that it is an unreasonable world, nor even that it is a reasonable one. The commonest kind of trouble is that it is nearly reasonable, but not quite. Life is not an illogicality; yet it is a trap for logicians. It looks just a little more mathematical and regular than it is; its exactitude is obvious, but its inexactitude is hidden; its wildness lies in wait. I give one coarse instance of what I mean. Suppose some mathematical creature from the moon were to reckon up the human body; he would at once see that the essential thing about it was that it was duplicate. A man is two men, he on the right exactly resembling him on the left. Having noted that there was an arm on the right and one on the left, a leg on the right and one on the left, he might go further and still find on each side the same number of fingers, the same number of toes, twin eyes, twin ears, twin nostrils, and even twin lobes of the brain. At last he would take it as a law; and then, where he found a heart on one side, would deduce that there was another heart on the other. And just then, where he most felt he was right, he would be wrong.

It is this silent swerving from accuracy by an inch that is the uncanny element in everything. It seems a sort of secret treason in the universe. An apple or an orange is round enough to get itself called round, and yet is not round after all. The earth itself is shaped like an orange in order to lure some simple astronomer into calling it a globe. A blade of grass is called after the blade of a sword, because it comes to a point; but it doesn't. Everywhere in things there is this element of the quiet and incalculable. It escapes the rationalists, but it never escapes till the last moment. From the grand curve of our earth it could easily be inferred that every inch of it was thus curved. It would seem rational that as a man has a brain on both sides, he should have a heart on both sides. Yet scientific men are still organizing expeditions to find the North Pole, because they are so fond of flat country. Scientific men are also still organising expeditions to find a man's heart; and when they try to find it, they generally get on the wrong side of him.

Now, actual insight or inspiration is best tested by whether it guesses these hidden malformations or surprises. If our mathematician from the moon saw the two arms and the two ears, he might deduce the two shoulder-blades and the two halves of the brain. But if he guessed that the man's heart was in the right place, then I should call him something more than a mathematician. Now, this is exactly the claim which I have since come to propound for Christianity. Not merely that it deduces logical truths, but that when it suddenly becomes illogical, it has found, so to speak, an illogical truth. It not only goes right about things, but it goes wrong (if one may say so) exactly where the things go wrong. Its plan suits the secret irregularities, and expects the unexpected. It is simple about the simple truth; but it is stubborn about the subtle truth. It will admit that a man has two hands, it will not admit (though all the Modernists wail to it) the obvious deduction that he has two hearts. It is my only purpose in this chapter to point this out; to show that whenever we feel there is something odd in Christian theology, we shall generally find that there is something odd in the truth.

I have alluded to an unmeaning phrase to the effect that such and such a creed cannot be believed in our age. Of course, anything can be believed in any age. But, oddly enough, there really is a sense in which a creed, if it is believed at all, can be believed more fixedly in a complex society than in a simple one. If a man finds Christianity true in Birmingham, he has actually clearer reasons for faith than if he had found it true in Mercia. For the more complicated seems the coincidence, the less it can be a coincidence. If snowflakes fell in the shape, say, of the heart of Midlothian, it might be an accident. But if snowflakes fell in the exact shape of the maze at Hampton Court, I think one might call it a miracle. It is exactly as of such a miracle that I have since come to feel of the philosophy of Christianity. The complication of our modern world proves the truth of the creed more perfectly than any of the plain problems of the ages of faith. It was in Notting Hill and Battersea that I began to see that Christianity was true. This is why the faith has that elaboration of doctrines and details which so much distresses those who admire Christianity without believing in it. When once one believes in a creed, one is proud of its complexity, as scientists are proud of the complexity of science. It shows how rich it is in discoveries. If it is right at all, it is a compliment to say that it's elaborately right. A stick might fit a hole or a stone a hollow by accident. But a key and a lock are both complex. And if a key fits a lock, you know it is the right key.

But this involved accuracy of the thing makes it very difficult to do what I now have to do, to describe this accumulation of truth. It is very hard for a man to defend anything of which he is entirely convinced. It is comparatively easy when he is only partially convinced. He is partially convinced because he has found this or that proof of the thing, and he can expound it. But a man is not really convinced of a philosophic theory when he finds that something proves it. He is only really convinced when he finds that everything proves it. And the more converging reasons he finds pointing to this conviction, the more bewildered he is if asked suddenly to sum them up. Thus, if one asked an ordinary intelligent man, on the spur of the moment, "Why do you prefer civilisation to savagery?" he would look wildly round at object after object, and would only be able to answer vaguely, "Why, there is that bookcase … and the coals in the coal-scuttle … and pianos … and policemen." The whole case for civilisation is that the case for it is complex. It has done so many things. But that very multiplicity of proof which ought to make reply overwhelming makes reply impossible.

There is, therefore, about all complete conviction a kind of huge helplessness. The belief is so big that it takes a long time to get it into action. And this hesitation chiefly arises, oddly enough, from an indifference about where one should begin. All roads lead to Rome; which is one reason why many people never get there. In the case of this defence of the Christian conviction I confess that I would as soon begin the argument with one thing as another; I would begin it with a turnip or a taximeter cab. But if I am to be at all careful about making my meaning clear, it will, I think, be wiser to continue the current arguments of the last chapter, which was concerned to urge the first of these mystical coincidences, or rather ratifications. All I had hitherto heard of Christian theology had alienated me from it. I was a pagan at the age of twelve, and a complete agnostic by the age of sixteen; and I cannot understand any one passing the age of seventeen without having asked himself so simple a question. I did, indeed, retain a cloudy reverence for a cosmic deity and a great historical interest in the Founder of Christianity. But I certainly regarded Him as a man; though perhaps I thought that, even in that point, He had an advantage over some of His modern critics. I read the scientific and sceptical literature of my time—all of it, at least, that I could find written in English and lying about; and I read nothing else; I mean I read nothing else on any other note of philosophy. The penny dreadfuls which I also read were indeed in a healthy and heroic tradition of Christianity; but I did not know this at the time. I never read a line of Christian apologetics. I read as little as I can of them now. It was Huxley and Herbert Spencer and Bradlaugh who brought me back to orthodox theology. They sowed in my mind my first wild doubts of doubt. Our grandmothers were quite right when they said that Tom Paine and the free-thinkers unsettled the mind. They do. They unsettled mine horribly. The rationalist made me question whether reason was of any use whatever; and when I had finished Herbert Spencer I had got as far as doubting (for the first time) whether evolution had occurred at all. As I laid down the last of Colonel Ingersoll's atheistic lectures the dreadful thought broke across my mind, "Almost thou persuadest me to be a Christian." I was in a desperate way.