To asses the strengths of the Ontological Argument for Gods existence, we firstly need to understand what it entails. The Ontological Argument looks at proof ‘A Priori’, which is Analytical truth, reason based proof. This can be explained by saying 1+1=2. We know this to be true, as it is based on reasoning, and is a logical statement. This can be seen as a strength of the Ontological Argument, the fact that it is logical and rational. It deals with knowledge gained independently of experience, innate knowledge. It does not use any external evidence, it simply uses the definition of the word ‘God’. It therefore claims that if you understand what God is, then you understand that he must exist.
St. Anselm, an Archbishop of Canterbury, first proposed the Ontological Argument in his book ‘Proslogian’, according to Anselm, both theists and atheists have a definition of God, if only for atheists to dismiss his existence. Therefore, Anselm claims, God exists in the mind. This could be considered a strength of the Ontological Argument for God’s existence. The fact that if you use the word God, then you, yourself must have an understanding of the meaning of the word. To use the word we show we have an idea of God which exists in our minds. However, existing in the mind is one thing, but to exist in reality is another.
‘Lord, not only are You that then which nothing greater can be conceived but you are also something greater than can be conceived’ St. Anselm, Proslogion.
As Anselm states above, God is that which nothing greater can be conceived, therefore not only must he exist in the mind, but in reality. This is because it is greater to exist in reality than simply in the mind. There is strength in this point, as what Anselm is saying is true. It is greater to exist in reality, that in the mind alone. For example if we had not eaten for a week, it would be good to imagine a 3 course meal, however, to actually receive that meal, and make it a reality, would be even better. As God is described as the greatest, then this helps to prove his existence.
Rene Descartes supported Anselm’s argument, he had strengths in his proposition in which he said that if your minds exists, then it is logical to assume that clear ideas which come into your mind are true. His proposition began with ‘I have an idea of God’ and finished with ‘Therefore God, as the clear and distinct idea of supreme perfection must exist’. He maintained that his idea of God is one of a supremely perfect being, and one of the attributes of perfection is existence. This is similar to Anselm’s argument, and bears the same assets of being logical and plausible.