This post is the fourth in a series on Pavel Tichý's "Existence and God" (J. Phil., August 1979, 403-420). In section II we find a critique of Descartes' Meditation Five ontological argument. Tichý claims to spot two fallacies in the argument. I will argue that only one of them is a genuine fallacy. One could present the Cartesian argument in Tichý's jargon as follows:
1. The requisites of the divine office include all perfections.
2. Existence is a perfection.
Therefore
3. The divine office is occupied.
Tichý finds two fallacies in the above Cartesian argument.
The first is that it assumes that existence is a first-level property, a property of individuals. For if existence is one of the requisites of the divine office, as it must be if existence is a perfection, then existence is a property that can be meaningfully attributed to individuals. But we have seen that for Tichý, existence is not a property of individuals but of offices. It is the second-level property of being-occupied.
The second mistake in the Cartesian argument is that it relies on the following fallacious argument-pattern:
P is a requisite of office O
Therefore
The occupant of O instantiates P.
The argument-form is indeed invalid. Let O be the office of King of France. Let P be being human. P is a requisite of O. But it doesn't follow that the occupant of the office of King of France is human. For there is no occupant. Similarly, even if existence were a requisite of the divine office, it would not follow that the occupant of the divine office exists. For the office may be unoccupied. All we can safely infer from the fact, if it is a fact, that existence is a requisite of the divine office is that, if the office is occupied, then the occupant exists.
This is a very old objection, and it strikes me as sound. The concept of God is the concept of a being possessing all perfections. Now let it be granted that existence is a perfection, a "great-making property" in Alvin Plantinga's phrase. From these premises we may validly infer that the concept of God is the concept of a being that exists, indeed, the concept of a being that is as inseparable from its existence as the idea of a mountain from the idea of a valley, to revert to a Cartesian analogy. Still, how does this get us to the conclusion that God exists? For all that this argument shows, the concept of God might fail of instantiation: there might not be anything that falls under it. If something instantiates the God-concept, then that thing has an essence which includes or entails existence. But from this one cannot validly infer that something does instantiate the God-concept, or occupy the divine office.
Of course, Tichy does not grant that existence is a perfection, a great-making property of God. For his whole point is that existence cannot be attributed to individuals. This yields a much more radical objection to the Cartesian ontological argument, an objection one finds already in Frege, but not before Frege: Kant does not anticipate Frege's exact point about existence, contrary to what many, including Tichy, think. (To establish this would require a separate post.) In The Foundations of Arithmetic, we read, "Because existence is a property of concepts, the ontological argument for the existence of God breaks down." (p. 65) This amounts to a very radical criticism since it implies that 'God exists,' interpreted as the attribution of existence to an individual is meaningless.
Now I reject this more radical Fregean objection to the ontological argument. First, it implies a theory of existence open to powerful objections, a couple of which are sketched here. Second, the argument for it is not compelling, as explained here.