Simple Defense of the Ontological as Argument

One of the Standard criticisms of the ontological argument takes the form of a reductio ad absurdum. Rather than beginning with the idea of God, critics begin with the idea of a non-existent or contingent object. They then purport to argue mutatis mutandis to the absurd conclusion that the non-existent object exists or that the contingent object exists necessarily. I shall develop a dialectic between Descartes and several of his critics to illustrate (and rebut) various forms of this reductio. The essence of my defense is the claim that Descartes' argument for God's existence ranges over a limited set of ideas—a set that excludes those ideas traditionally used to formulate the reductio. Furthermore, if the Doctrine of Divine Property Simplicity is true (as Descartes believes that it is), then the set of ideas has only one member—the idea of God. And if this is the case then no reductio of this sort can ever work.