Much of the fascination and puzzlement caused by ontological arguments may be to do with the fact that they arrive at their conclusion, which consists in nothing less than the existence of God, in an astonishingly simple way. The Anselmian version, as a case in point, can be explained to lay persons in a few minutes. How can it be that such an innocent-looking argument establishes such a weighty conclusion? This perplexity has provoked analytically minded philosophers to try to find some kind of formal or informal fallacy in its structure ever since Anselm stated it for the first time. In...