Philosophy of Religion Ontological Argument

The Ontological Argument So, we turn to the ontological argument for God’s existence. It’s called this because ontology is the study of being (or existence), and what is at issue is God’s being (or existence). Basically, the argument says that it is in God’s nature to exist. So, he must exist.

Another, perhaps better, way to roughly put the argument is this: I can conceive of a perfect being. But if he doesn’t exist, then he isn’t perfect. So, he must exist. Before we get to the argument itself, we need to consider Anselm’s starting point. This starting point is that God is the greatest possible being. Basically, Anselm asks us to imagine God. If we are truly imagining God, then what we imagine must be something entirely unsurpassable in greatness (perfection). For God, if He exists, must, by definition, be as excellent as anything possibly could be. Accordingly, our concept of God is a concept of the being than which none greater is possible.

It would seem that we do in fact have such a concept (that is, it seems that we can imagine such a being). But so what? That doesn’t prove much of anything. That’s why this is just the starting point. Anselm’s task is then to prove that this being -- the being than which none greater is possible -- is not just a concept. For, if it were just a concept, then God would only “exist in the understanding” (i.e., in our imaginations). So, Anselm’s task is to show that such a being actually exists. To understand this, consider the following two categories: possible things and impossible things.

Possible Things Impossible Things Unicorns Fountain of Youth The Planet Mars The Abominable Snowman Chairs Round squares God 4-sided triangles People Married bachelors

Now let’s divide the possible things into two categories: Things Which Don’t Exist Things Which Exist Unicorns Chairs Fountain of Youth The Planet Mars The Abominable Snowman People (Exist in the understanding only) (Exist in the understanding and in reality)

The question confronting us is then: In which of these categories do we place God? Anselm is going to try to show that we must place God in the category on the right (possible things which do exist). The idea behind Anselm’s argument is this: If we were to suppose that God doesn’t exist (i.e., that God goes in the category on the left), we’d get a contradiction. And contradictions are necessarily false. So, our supposition would entail something false. But something true cannot entail anything false. So, our supposition cannot be true -- it must be false. This means that it’s false that God doesn’t exist. So, God exists.

The argument is a reductio ad absurdum, which is an argument form that tries to establish that a particular position is false by reducing it to absurdity. Consider: P1) Joe is taller than Suzy P2) Mary is taller than Joe. P3) Suzy is taller than Mary. (Assumed for RAA) C1) Therefore (P2/P3), Suzy is taller than Joe. C2) Therefore, (C1/P1) Suzy is taller than Joe and Joe is taller than Suzy. C3) But this is a contradiction (RAA), which means that (P3) is false. C4) Therefore, Suzy is not taller than Mary.

the ontological argument P1) God (the being than which none greater is possible) exists in the understanding. P2) God could exist in reality. P3) If something exists only in the understanding and yet could exist in reality, then it might have been greater than it is. P4) Suppose that God exists only in the understanding. (Assumed for RAA) C1) So, God might have been greater than he is. C2) So, God is a being than which a greater is possible. C3) So, the being than which none greater is possible is a being than which a greater is possible. C4) But this is a contradiction (RAA), which means that (P4) is false -- it’s false that God exists only in the understanding. C5) Therefore, God must exist in reality as well as in the understanding.

Notice that this argument (unlike the other two) is entirely a priori. It relies on no experience whatsoever, but is assembled simply by reasoning alone. All that is required to understand this argument is a bit of time and a lot of thinking. For you don’t need to go do experiments, or collect data, or spend hours in a lab with mice. All you need is the concept “God”. Once you have that concept, you can just sit back in your arm chair and -- viola! A proof!

But is it a genuine proof? That is, does the argument really work? Whether it works or not the ontological argument must be considered one of the greatest achievements of the human intellect. By pure reasoning alone, using a few more or less commonsense premises, Anselm has put together an impressive argument for God’s existence. It cannot be denied that the argument is worthy of our respect. Unfortunately, being impressive and worthy of respect is not enough. In order to work, the argument must be much more than that -- it must be sound. Is it?

One might challenge (P3): If something exists only in the understanding and yet could exist in reality, then it might have been greater than it is. (P3) assumes that existence is a great-making property. For a thing that has the property of existing is greater than that same thing when it doesn’t have that property. And is it really the case that an X that exists is greater than an X that does not? (Importantly, by greater we do not mean simply “more valuable”).

So, is existence really a property? It seems not. What is more, the claim relies on the fact that existence is a property. What are properties? Things like being round or red or fuzzy – they are attributes or characteristics possessed by an object. So, is existence really a property? It seems not. To see this, consider an apple pie. Suppose you give me a recipe that will enable me to make an apple pie. Do you need to put “existence” on the list? And is existence something we would list as one of its properties? No.

But there are more fundamental problems to address. A monk named Guanilo raised perhaps the most significant objection to the ontological argument. What Guanilo did was show that the argument must be unsound. Why? Because it can be used to prove that all kinds of crazy things exist. Since we know these crazy things don’t exist, we can be sure that the argument is flawed in some way. So, the argument fails to prove that God exists.

Isle of the Blest P1*) The Isle of the Blest (the island than which none greater is possible) exists in the understanding. P2*) The Isle of the Blest could exist in reality. P3*) If something exists only in the understanding and could exist in reality, then it might have been greater than it is. P4*) Suppose that the Isle of the Blest exists only in the understanding (Assumed for RAA). C1*) So, the Isle of the Blest might have been greater than it is. C2*) So, the Isle of the Blest is an island than which a greater is possible. C3*) So, the island than which none greater is possible is an island than which a greater is possible. C4*) But this is a contradiction, which means that (P4) is false – it’s false that the Isle of the Blest exists only in the understanding. C5*) Therefore, the Isle of the Blest must exist in reality as well as in the understanding.

Of course, this is absurd. We know that we can’t prove that a particular island exists through an a priori argument. In order to find out whether a given island exists or not, we have to go out and look for that island - we can’t just define it in a certain way and then construct an argument that proves that it exists. So, clearly there is something wrong with Anselm’s reasoning. If this is correct, then the ontological argument fails to establish that God exists.