There is a story about a schoolboy who was asked what he thought God was like. He replied that, as far as he could make out, God was ‘the sort of person who is always snooping around to see if anyone is enjoying himself and then trying to stop it’. And I am afraid that is the sort of idea that the word Morality raises in a good many people’s minds: something that interferes, something that stops you having a good time. In reality, moral rules are directions for running the human machine. Every moral rule is there to prevent a breakdown, or a strain, or a friction, in the running of that machine. That is why these rules at first seem to be constantly interfering with our natural inclinations. When you are being taught how to use any machine, the instructor keeps on saying, ‘No, don’t do it like that,’ because, of course, there are all sorts of things that look all right and seem to you the natural way of treating the machine, but do not really work.