In Descartes fifth meditation he tried to use a proof of God's existence that is known as the ontological argument. I will attempt in this paper to refute the argument. I will be using some citations from Kant's Critique of Pure Reason, and will also be using some of my own thoughts and thoughts that are derived from class discussion.
I think that it is important to first try to arrange Descartes" argument into point form, so as to better be able to analyze it. I have translated Descartes argument like this:.
1. If I clearly and distinctly perceive some property as belonging to the idea of some thing, then that property really does belong to that thing.
2. The idea of God is of a perfect being.
3. Not existing would be an imperfection.
4. Since the idea of God is of a perfect being, it must be true of the idea that it has the property of always existing, and I clearly and distinctly perceive this.
5. Thus it follows from premises 1 and 4 that God must exist. .
Now that we have the argument in point form, let us move on and see where it is weak to criticism.
Let us begin with the first premise. We can argue that this very first premise already assumes the existence of God. For what Descartes is saying is, let us suppose a thing, simply as an idea. If this idea has this property, and I clearly and distinctly perceive it as having that property, then the object that corresponds to the idea must have that property. How did we get from the idea of the thing to there really being a thing that has all the properties that the idea has.
Another objection can be raised by examining the example of a mountain and a valley, the same example that Descartes uses . He says that it is impossible for us to separate the idea of a mountain from a valley, but it surely does not follow that a mountain and a valley exist in the world, only that were there to be one, there would be the other. This however is not the same way with God.