Ontological Argument - Edexcel A2

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Essay on the Ontological Argument

Clarify the key concepts of the ontological argument for the existence of God (26 marks.)

In one form or another, the Ontological Argument has existed for close to a thousand years, yet is noteworthy for other reasons than its longevity. The only a priori argument for the existence of God, it attempts to prove the existence of God using the definition of God Himself to draw out His existence.

Although never intended to be an argument for the existence of God, the first record of the Argument is found in Anselm’s Proslogium, where he says, written here in syllogistic form, that God must exist:

P1: God is the greatest conceivable being

P2: It is greater to exist in reality than just in the mind.

C: God must exist.

This is considered to be a weak argument, and a fellow monk of Anselm, Gaunilo, strongly criticised Anselm’s argument in his book On Behalf of the Fool, forcing Anselm to justify his comments. Gaunilo argued that the imagination of something perfect does not automatically mean that it exists; he used the example of a perfect island. Everyone could imagine a perfect island, but that does not mean that it exists. Anselm, in Responsio, retorted by saying that an island, perfect or otherwise, would still be contingent, not contingent, as the God of modern theism would have to be. In the Ontological Argument God, as He is in many other arguments, is the exception to the rule, as He is considered to be necessary being. This argument is countered by the 21st century philosopher Markham, when he says that  

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The argument was next revised by Rene Descartes in the 17th century. He took a different approach to Anselm, by arguing that God, as the most perfect being imaginable would have to have all perfections possible; existence being a key one.

Using an analogy of a triangle, Descartes said, in Meditations, that although an actual triangle does not have to exist, the mention of a triangle gives the image of a shape with 3 sides and angles totalling 180°. In a similar way, the idea of God gives the image of an omniscient, omnipotent, omnibenevolent being – in ...

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