Imagine that you move to a little Carribean paradise. Your mode of transportation is a motorcycle. However, you have frequent guests — old friends from the snowy north from where you once lived — and you want to get another motorcycle that your friends can ride while they’re in town. So you’re looking through a Neiman Marcus catalogue one day when you spot a Dodge Tomahawk for sale. (The Tomahawk is a non-street-legal motorcycle that Dodge built for the 2003 Detroit Auto Show with a Dodge Viper V-10 engine and 500 bhp. They have since been offered for sale through Neiman Marcus with a handful having been purchased.) Money is no issue and there are no traffic laws in your paradise, so you purchase one of the motorcycles. Sadly, you soon regret your purchase. Most of your friends are simply unable to ride the Tomahawk. One of them immediately hit the bushes at the end of the driveway. Another almost flew off a cliff. Gradually it dawned on you: a motorcycle may be great in that it is working fine and has all the potential for stellar performance. But if people are unable to ride it when they want to then what’s the point? You didn’t buy it to sit in your garage.
Sadly, the ontological argument is the Dodge Tomahawk. All the parts work. The acceleration is amazing. The argument establishes that if it is possible for a most perfect being to exist then the most perfect being must exist. And yet offer your friends to take it out on the road and they run immediately into the bushes or veer dangerously near a cliff.
There seem to be two basic problems. The first problem is a failure to understand the terms of the argument. For example, the form I gave depends on the concept of a possible world as a way to analyze possibilia (that is, modal terms like necessity, contingency and possibility). If you are not familiar with the concept of possible worlds then you won’t get the force of the argument.
The second problem can best be defined as a general incredulity toward the very notion of coming to know the existence of something a priori. So we must contend with complaints that there is a conjuring trick going on somewhere, or to deal with facile and distracting silliness about unicorns and the like.
That has always been the unique challenge of the ontological argument. The objections may be wide of the mark. The argument may run well. But if it sits in the garage like an untameable Tomahawk then what benefit is it? Motorcycles were made to be ridden, and if people cannot ride them then they’re not much good, are they? And if arguments were made to lead people to truth, then even if the argument has true premises and a conclusion that follows from the premises, they’re not much good if people cannot follow them.
It doesn’t mean you get rid of the Tomahawk. But it is probably time to put in an order for that cherry red Vespa.