Belief sloshes around in the firmament like lumps of clay spiralling into a potter's wheel. That's how gods get created, for example. They clearly must be created by their own believers, because a brief resume of the lives of most gods suggests that their origins certainly couldn't be divine. They tend to do exactly the things people would do if only they could, especially when it comes to nymphs, golden showers, and the smiting of your enemies.
Terry PratchettThe secret is not to dream," she whispered. "The secret is to wake up. Waking up is harder. I have woken up and I am real. I know where I come from and I know where I'm going. You cannot fool me any more. Or touch me. Or anything that is mine.
Terry PratchettA lot hinges on the fact that, in most circumstances, people are not allowed to hit you with a mallet. They put up all kinds of visible and invisible signs that say, 'Do not do this' in the hope that it'll work, but if it doesn't, then they shrug, because there is, really, no real mallet at all.
Terry Pratchett