All the real argument about religion turns on the question of whether a man who was born upside down can tell when he comes right way up. The primary paradox of Christianity is that the ordinary condition of man is not his sane or sensible condition; that the normal itself is an abnormality. That is the inmost philosophy of the Fall. In Sir Oliver Lodge's interesting new Catechism, the first two questions were: "What are you?" and "What, then, is the meaning of the Fall of Man?" I remember amusing myself by writing my own answers to the questions; but I soon found that they were very broken and agnostic answers. To the question, "What are you?" I could only answer, "God knows." And to the question, "What is meant by the Fall?" I could answer with complete sincerity, "That whatever I am, I am not myself."If you are not yourself, what are you? Yourself, plus something else: the orthodox answer being yourself plus original sin. Like a chimera -- or, as Chesterton himself more rightly noted, like a centaur or a mermaid -- you are a human being, and also an animal. You are in the world, but not of it.
The recognition that we are monsters is meant to be liberating. In recognizing that we are not perfect just as we are, we are free to try to cut loose of what is wrong with us. Even if we fail, at least we know in what direction to strive.