You: Why must I conclude that there is one, all-powerful God who organized the world? Since there is no way to disprove that water elves exist — in fact, they may go out of their way to look like a natural process — there is no way to disprove the existence of a whole host of supernatural creatures! There might be gnomes that cause earthquakes, dwarfs that make thunder, sprites that carry smells from fresh-baked bread to my nose, and goblins that steal my socks from the dryer.

Aaron: Ah! I have you there! By the concept of parsimony, the least complicated example is the most likely to be correct, and wouldn't you think that one God is much less complicated than all these creatures you postulate?

You: On the contrary, the God that you propose is much more complicated. Your God is omnipotent, omniscient and eternal while my bread sprites and their friends are just a little magical. It is much more likely that there are a whole host of creatures that are slightly supernatural than that there is even one creature who is infinitely so.

Aaron: We are bordering on the ridiculous here. It is obvious that your elves and such do not exist...

You: It is not "obvious" to me at all, but I do not believe in them because I have no compelling reason to believe in them. And I do not believe in your God for the same reason.

Aaron: Here, then, let me give you a compelling, logical reason.