We have from time to time noted that theories of a multiverse suffer from being in stark conflict with the law of parsimony. This is the law that tells us that given several competing explanations for some phenomenon, the simplest explanation that's compatible with the known facts is to be preferred.
Evidently, a commenter at Uncommon Descent has opined that the multiverse theory, the idea that there are, besides our own world, an infinity of universes exhibiting an infinity of laws and parameters, is not incompatible with the law of parsimony. I find this hard to accept, as does Barry Arrington. He explains his reasons here.
Arrington doesn't explain his objection quite as thoroughly as a reader unfamiliar with the multiverse concept might like, but what he's getting at is that any theory that multiplies entities to infinity in order to explain the existence of the unimaginable precision of the fine-tuning of this world is by definition unparsimonious. This is especially true given that there's no evidence of any other universes, much less an infinity of them. All we know is that some versions of string theory allow for them, but we don't even know if string theory is true.
Since the alternative theory is that there is just one world, the world of our experience and the only world we have evidence for, it would seem that that is the simplest hypothesis that fits all the facts and it really is hard to understand how some people justify thinking otherwise.
Anyway, Arrington's post gives us, besides us a bit of unnecessary hyperventilation, a helpful and succinct overview of the law of parsimony, also known as Occam's Razor, and a little background on William of Ockham himself.
Check it out.RLC