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 organizing 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....whenever we feel there is something odd in Christian theology, we shall generally find that there is something odd in the truth.