In his Meditations on First Philosophy, Rene Descartes outlined two proofs for the existence of God – one in Meditation III and a second in the fifth meditation. Proof of the existence of an omnipotent, omniscient and all good deity (Descartes’ concept of ‘God’ being firmly rooted in the Christian tradition) is necessary, according to Descartes, for the meditator to proceed from the state of Cartesian doubt into reliable knowledge of the external world. The claims Descartes lays in order to make this step are the ‘trademarkargument and the ontological argument, the latter of which shall concern this investigation. It is necessary to discuss this argument and its refutations in order to critically examine its validity.

The Ontological Argument

The ontological argument is an a priori argument in that it does not rely on experience to prove its point – that God exists. Descartes professes this argument in Meditation V as such:

“When I concentrate, it is quite evident that existence can no more be separated from the essence of God than the … idea of a mountain can be separated from the idea of a valley… Hence it is just as much of a contradiction to think of God (that is, a supremely perfect being) lacking existence (that is, lacking a perfection) as it is to think of a mountain without a valley.”
In this way, Descartes is presenting the idea that God has ultimate perfections, one of which is existence. Were God not to exist, he would not have all perfections. It therefore follows from the (Christian) definition of God that he exists just as it follows from the definition of a triangle that the total of the three vertices is equal to two right angles. This can be summarised as
  1. God has all perfections
  2. Existence is a perfection
    ------
    Therefore, God exists.
There are several counter arguments to this – those that oppose the premises themselves and those that accept the argument but not its consequences.

Existence is not a property

The first and most cited criticism of Descartes’ ontological proposition is that the idea of ‘existence’ is not a property as such can be applied to something as could colour or shape or strength: it is not a predicate. Kant illustrates this with a comparison between the ideas that “God is merciful” and “God is existent”. These two sentences are not of the same logical form: existence or non-existence does not change the essence of God, whereas to negate “God is merciful” would alter the concept of God itself. Hirst summarises this as follows – “The God who exists does not have an extra quality as against a God who does not exist: in idea he is exactly the same.” This refutation is in turn countered by Malcolm, who argues that it makes no sense to speculate on an eternal being ceasing to exist, as comparisons of God to finite things are just irrelevant. Malcolm stresses Descartes’ point (what he made in the replies to the objections to the Mediations) of the necessary existence of God – God is a unique case and for God existence is a property – which frees the ontological concept of internal contradiction as highlighted by Kant. In Descartes’ own words:

“…In the case of God necessary existence is in fact a property in the strictest sense of the term, since it applies to him alone and forms part of his essence as it does no other thing.”
This point can again be refuted, however, by looking at Gassendi’s objection –
“Neither in God nor in anything else is existence a perfection, but rather without that there are no perfections… Existence cannot be said to exist in a thing like perfection; and if a thing lacks existence, then it is not just imperfect, it is nothing at all.”
From this we can extrapolate the idea “If God exists, then he exists”, which is, from the contender’s perspective, all that Descartes, Malcolm and other supporters of the ontological argument can achieve with the stated argument. The ‘Fregean solution’ appears to support this: mathematician Gottlob Frege’s ontology poses the idea of existence being a ‘second level’ concept. He suggested that rather than ‘existence’ being a property of an object, it is that of a concept. This property of existence is there “just in case it has a non-empty extension” – i.e. just in case God exists.

Absurd consequences

A second criticism of the ontological argument is that which demonstrates the absurdity of the consequences of applying the argument to other forms than God. Were the ontological argument valid, the perfect desert island, boyfriend, society and so on could all be defined into existence. This is, quite obviously, not the case! It may well be possible to define the concept of a perfect desert island, but not possible to just make it exist. To defend the ontological argument against this sort or criticism, it could be argued that the perfect island, boyfriend or society are only perfect examples of different types of things, and, again, a supremely perfect deity does not fall into the same category, as the deity has, and is, all perfections, so is a “special case”.

Nothing perfect could exist

A further development of the idea “If God exists, then he exists” is the idea that nothing that is perfect might exist. Descartes states theories about triangles – “…its three angles equal two right angles” in abstraction as to whether anything triangular exists or not. Similarly, it can be argued, he presents theories about God in abstraction from whether God exists or not. This idea was put forth by Hume – that something can be thought of as existing, but that has no bearing on the thing’s actual existence. Take for example the existence of $100: the can be thought of as existing, yet that holds no bearing on whether it exists immediately. Even if in spite of the other refutations existence is accepted as a component of perfection, this is perfectly compatible with nothing perfect existing, as Kenny concludes “…If nothing is perfect then nothing is divine, and there is no God, and so Descartes’ proof fails.”

To prove God’s existence is a necessary stage for Descartes in the Meditations. Unfortunately, as shown by the refutations of Descartes’ proposition in the fifth meditation, the ontological ‘proof’ is not sound. It can be countered as the idea of existence being a perfection is questionable, also that if the ontological argument was sound, it would allow all sorts of things to be defined into existence, which are, quite frankly, impossible. Furthermore, a perfect thing might not even exist, so God may have every perfection, but still may not exist. However, it should be considered that the ontological argument is one of two such proofs in the Meditations, therefore (unlike St. Anselm!) Descartes did not design this as an independent, self contained proof of God’s existence, so perhaps it should not be judged as such. Although the ontological argument does not prove the existence of God, neither do the refutations prove his non-existence. In this way it can be said, as Hirst argues, that the ontological argument shows only that the question of God’s existence cannot be settled by conceptual thoughts of God.

Coming soon... The Trademark Argument!

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