 These premises entail that God exists in no possible world, and hence that God does not exist in the actual world. Considered together, the argument and the counterargument just mentioned plainly do not give anyone a reason to prefer theism to non-theism, and nor do they give anyone a reason to prefer non-theism to theism. So the sample argument is unsuccessful: it doesn’t supply an all-things-considered reason to prefer theism to non-theism (just as the counterargument doesn’t supply an all-things-considered reason to prefer non-theism to theism).