There are other flaws in Anselm’s argument. The fact is, even if we could imagine something which could not be imagined not to exist, we can easily imagine God not existing, demonstrated by the many examples of people trying to disprove his existence.
The next classical ontological argument was presented by Descartes. He argued, quite simply, that existence is a predicate of a perfect being: God must exist, because without existence, He would not be supremely perfect. Descartes used the example of a triangle – if we were to imagine a triangle without three sides, the idea would be absurd as it would no longer be a triangle.
This was opposed by Emmanuel Kant. He declared that Descartes’ claim, that denying God’s existence would be equivalent to denying that triangles have three sides, is wrong. His main argument was that if you dismiss the idea of the triangle and the three sides, then there is no longer a problem.
Kant also argued that existence is not a predicate, because it tells us nothing of the nature of the subject. To reverse the statement, saying that God does not exist, would be contradictory, because this would be saying that God lacks existence, but if He does not exist, how can He lack anything?
There are also some more recent additions to the Ontological argument. Norman Malcolm (1911-1990) extended Anselm’s ‘Prosologion 3’: Either God has necessary existence, or He does not exist. He developed this by saying essentially that, if God did exist, He must always have existence, because for Him to have ever come into existence would mean that He has limits, and would have had to have been created by a greater being, therefore making Him not ‘That than which nothing greater can be conceived’. Therefore, He either once came into existence, which would be impossible as He is by definition ‘greater than the greatest being’, or He had always existed, consequently making Him necessary.
Two more recent objectors to Anselm and Malcolm’s type of argument were Gotlobb Frege (1848-1925) and Bertrand Russell (20th Century). Frege objected to both of the classical arguments by claiming that they used ‘predicate’ incorrectly. He perceived two types of predicate – ‘first-order’ and ‘second-order’. Apparently, first-order predicates tell us about the character or property of something – it’s nature. Second-order predicates are merely concepts or notions, such as existence. He claimed that Anselm, Descartes and Malcolm used existence as a first-order predicate, but it is actually second-order.
Russell contended the use of existence as a predicate at all – he maintained that existence was not something things have; it is concerned with the idea of a thing. He developed this by saying that to describe something is only to provide an intention concerning an object. Existence is merely an extension of an intention to describe. Concerning the description ‘Than than which nothing greater can be conceived’, Russell redefined it as the totality of everything that can be imagined by the human mind. He agreed that this was a correct definition of God, but not that it proves God’s reality.
Plantinga argued in support of the ontological argument, but presented his own explanation for the logical existence of God. He presented the idea pf ‘possible worlds’ – that every single possible scenario in the universe is played out in a possible world, and as scenarios are limitless according to the different possibilities, the number of worlds is infinite.
For all possible scenarios to be played out, there must be a world in which there is a being of ‘maximal greatness’. But, for it to be ‘maximally great’, it must exist in all possible worlds. Then again, apparently this is not God. This is because there will be the possibility of a being more morally perfect, more powerful and more knowing. So he puts forward the idea of ‘maximal excellence’, and claimed that maximal greatness demands maximal excellence.
If this being exists in all worlds, it must exist in all worlds. This being is God.
On the other hand, Plantinga did not take into account that for there to be always one more possible world, there is the possibility, and therefore existence, of a being more great than even this maximally great and excellent being, and one greater than this, and so on. There is no limit, and we cannot know if this being is God. One can also, following Kant’s example, dismiss the idea of any other possible worlds, and so dismiss Plantinga’s theory.
Brian Davies, a current philosopher, opposed Plantinga’s theory by stating that even if we accept the possibility of a being with maximal greatness and excellence, we are not necessarily accepting it’s existence. All we can conclude is that God is possible, not actual.
He also disagreed with the classical ontological philosophers. He argued that something to existing in order to have a particular predicate is not logical. Something ‘is’ can be used to define something, or to state its existence, but not one as a result of the other. The second use does not say anything about the object, whereas the first defines it, but does not require its existence. For example: ‘a pixie is a little man with pointed ears. Therefore there exists a pixie.’
In conclusion, the ontological argument is successful only if one already believes in God’s existence, otherwise flaws are easily noticed. All logical explanations for God’s existence were written by those who assumed it already, and were merely searching for ways to explain it.
But, all arguments in opposition also have flaws. One could continue forever finding flaws in arguments and then flaws in these flaws and so on. No conclusions can be successfully reached. The ontological argument is successful for believers who already have the assumption that God exists, but does not prove His existence. But neither do the oppositional arguments disprove Him. If God really were ‘That than which nothing greater can be conceived’, then He is greater than all explanations, so all explanations must be flawed and will never successfully prove Him. If by definition He is also limitless, there would be no way to disprove him either, as there would always be another property of him to disprove.