Ontological Argument Strengths

Strength and weaknesses of ontological argument
The Ontological Argument was, and still is, a hot-topic for debate among philosophers; many famous philosophers have published criticisms of the theory including Immanuel Kant and St. Thomas Aquinas. This obviously raises questions regarding whether or not this argument works. While there is no clear-cut answer to these questions, I personally believe that the negatives of this argument outweigh the positives, thereby making it a weak argument.
The first published criticism of Anselm’s Ontological Argument was from Gaunilo in his book In Behalf of the Fool (making reference to the fool in the book of psalms who didn’t believe in God). While Gaunilo was a firm believer in God (and was in fact
Thomas Aquinas. Again, he believed in God but disagreed with Anselm’s argument proving his existence. Aquinas raises questions about God’s self-evident existence. He claims that things can be self-evident in two ways: in itself and both in itself and to us; even though something may exist self-evidently in itself, this self-evidence may not be known to us as humans and therefore, its existence would not be self-evident to us. This is exactly what Aquinas proposes God to be. God is self-evident in himself because he is his own essence. However, seeing as this essence is unknown to us (as we do not know enough about him), the statement ‘God exists’ is not self-evident to us. This, again, is another criticism which holds weight against the Ontological Argument, highlighting a glaring weakness in its
Kant (who was an atheist) published a book called A Critique of Pure Reason in which he attempted to contradict both Descartes’ and Anselm’s versions of the Ontological Argument in two different ways. In his first argument, Kant begins by hypothetically accepting that existing is indeed a defining predicate of God (which both Descartes and Anselm claim it is). He then goes on to argue that, even if this were true, there would be no contradiction in altogether rejecting the concept of God. For example, you may understand that having a single horn on its head is a defining predicate of a unicorn. However, this does not mean that it would be contradictory to not believe in unicorns or magical horses with horns. By this logic, you could also claim that you agree that if God did indeed exist, he would necessarily exist but that you do not believe in God or his necessity without contradicting yourself.
In Kant’s second argument, he attacks the Ontological Argument at its base by claiming that ‘existing’ could not possibly be considered as a defining predicate as it does nothing to change the definition of the being in question; two people – one of whom believes in unicorns and one who doesn’t – would most likely share the same idea of what a unicorn is. While these two people would disagree on whether or not unicorns were real, they would not disagree on what a unicorn was. Therefore,