The ontological argument was first formulated by St. Anselm in the 11th century. It argues the existence of God from a deductive and a priori stance. God is a being than which none greater can be conceived. This is the response given by St Anselm to the fool in the psalm who believed there was no God. St Anselm the Archbishop of Canterbury and of the Benedictine Order explained that for God to exist in the mind he would not be the greatest being. However were God to exist in the mind and reality this would make a being ‘than which none greater can be conceived’, this means God must exist.
This demonstration for the existence of God was immediately criticised by his contemporary Gaunilon. He argued that Anselm’s argument could easily be used to prove the existence of many different beings or even places. In Gaunilon’s ‘response on the behalf of the fool’, he argued that he could conceive of a perfect island ‘blessed with all manners of delight’, yet it did not mean it must exist. However, Anselm responded to this claim arguing that a perfect island contains contingency; it is dependent, whereas God possesses aseity, is self-sufficient. This means that God’s existence is therefore, necessary, independent.
Descartes famously wrote his version of the ontological argument in the ‘Meditations’ in which he argued that God is an infinite being, perfect. For God to remain perfect he must then retain existence. He used the illustration of a triangle with three angles which all add up to 180 degrees. This quality of the triangle allows the triangle to be perfect and to be defined as a triangle. If the angles were taken away from the triangle it would no longer be a triangle. This is similar as to God; he could not be God if he did not exist. This proves according to Descartes that God’s existence is necessary.
But, it can be argued that the ontological argument is using an analytic format to define God as existing. Immanuel Kant refutes this as he believes that existence as a predicate or property cannot define God. For instance, the analytic statement ‘a spinster is an unmarried woman’ is tautological and true by definition. But if you were to add the predicate existence it would have no direct effect on the statement, this means that existence cannot be a property of God.
David Hume also went on to support this idea, as we cannot prove that existence is even a positive attribute, we know that ‘evil’ exists yet could this ‘existence’ be the same as the ‘existence’ of God? They would argue that the ontological argument failed to understand and make existence a meaning of God.
However, there have been responses by other philosophers such as Frege who argues that existence is actually a first level predicate which is able to explain the second level predicate. For instance, the ‘greenness of the apple’ is known through our senses but by adding ‘the greenness exists’ we are able to understand that such a predicate exists in reality. This means that ‘God exists’ allows us to understand that such a being as powerful as God does exist in reality as well as the mind.
However from an empirical view, Thomas Aquinas would argue that the flaw in the ontological arguments attempt to demonstrate God’s existence stems from the fact that Anselm wanted to argue that God’s existence can be proven from ‘de dicto’ instead of what is ‘real’, and this caused the argument to be weak. On the other hand, some will still argue that St Anselm and the ontological argument is still strong in the second half, ‘God is a necessary being’. This is due to the fact that only God’s existence can be either necessary or impossible and because it is possible, God is proven to exist.
To evaluate the whole ontological arguments’ attempt to prove and demonstrate God’s existence, it is clear due to the deductive stance, it shouldn’t be argued as the conclusion drawn must be ‘God is a necessary being’, ‘God is a being than which none greater can be conceived’. But as soon as you understand that definition you will find that it could be used to prove the existence of many things and beings. The ontological argument proves the idea that if God exists he is going to be a necessary being, but it does not prove that he actually does exist. Therefore as Richard Dawkins would describe it ‘infinite, playground argument’ and does not demonstrate God’s existence.