Here’s an abstract view of how the Ontological game is played.
A philosopher constructs some property, p, and asks you to consider the following statement:
(1a) You can imagine that a thing with property p exists.
Or alternately, if the philosopher wants to use modal logic,
(1b) It is possible that a thing with property p exists.
Now, unless p is blatantly self-contradictory, proposition 1 (in either version) usually appears pretty plausible. Of, course
(2a) You can imagine that a thing with property p does not exist.
and
(2b) It is possible that that a thing with property p does not exist.
also seems pretty plausible.
Now for the trick. A clever philosopher can construct a p such that (1) and (2) can be shown to contradict each other! How should we resolve this awkward situation?
Before going any further, let’s make this slightly less abstract. Specifically, suppose that in addition to the above, p is some manner of “god-like” property; that is, p is constructed so that it is natural to identify the thing exhibiting property p as god.
So, what are we to conclude from this state of affairs?
Some theologians want to claim that this proves that god exists. This is not terribly persuasive in absence of some good reason why we should accept (1) and reject (2), rather than vice-versa.
Williams wants to claim that the ontological argument shows that atheists must absolutely reject the possibility that god exists. This is imprecise. What is shown is that atheists must reject the possibility that a thing with property p exists; invariably, it’s possible for a being to be quite recognizably god-like without strictly exhibiting p. This shouldn’t come as a surprise to anyone, since it’s not the first time someone attributed properties to god which turned out to be paradoxical. For example, omnipotence (or, at least, a naively literal conception of omnipotence) is a thoroughly paradox-ridden concept. But even if omnipotence is paradoxical, and some people say god is omnipotent, this doesn’t imply that god doesn’t exist. A being who is not literally omnipotent could still possess powers deserving of the appellation “god-like”. Likewise, in these ontological arguments, to reject the possibility that a thing with property p could exist isn’t the same thing as concluding a priori that god (in the more general meaning of the word) cannot possibly exist.
Alvin Plantinga wants to claim that the ontological argument, though it doesn’t actually prove that god exists, demonstrates that it is rational to believe that god exists. Basically, he’s says that we have to either accept (1) and reject (2), or vice-versa, and the former option is just as good as the latter.
Actually, no. There are excellent reasons why we should accept (2) and reject (1) whenever we are confronted with this situation. Like Hume and Dawkins, I think that it’s pretty laughable to attempt an a priori proof of the existence of anything. Playing word games and examining your own mind just isn’t going to tell you that much about the world outside of your own skull.
But maybe you don’t share our empiricist leanings. Even so, you should reject (1). The reason is this: if you accept (1), it is ridiculously easy to use ontological arguments to prove the existence of all sorts of silly things. Here’s one example:
- I can imagine a maximally sexy woman.
- Youthful women are sexier than old/dead women; mortal women must eventually grow old and die, and thus be less sexy than an immortal, eternally youthful woman.
- A woman who exists in the real world is sexier than one who only exists in my mind.
Hence, there must exist in the real world an immortal, eternally youthful, maximally sexy woman; let’s call her, oh, Aphrodite. To the best of my knowledge, this ontological proof is original, although I wouldn’t be too surprised to find out that someone else thought of it first. The philosophic literature has no shortage of parody ontological proofs. (Exercise for the reader: use an ontological argument to refute the second law of thermodynamics. Hint one, hint two.) Ontological arguments are pretty much the quintessential example of bullshit sophistry.
It is possible, in principle, that all of the many, many ontological parodies are flawed, and somehow, the only true contradictions between (1) and (2) occur for p’s which are “god-like”. But if any of you are tempted to start a crusade against ontological parodies, please pause for a moment. Pause to ask yourself whether your desire to start skewering ontological parodies stems from an earnest desire to discover the truth, whatever it may be, or from a need to provide the less credulous part of your mind with some justification for believing what you already believe and want to keep believing.