I find it difficult to critique something if you have not read the argument (assuming, for example, it is in a textual or narrative form) in its designated context. We moderns may struggle with a plethora of classical problems that contained phenomena, terms and language that don’t quite mean the same as they used to. For instance, those who have read the Republic will find it strange that only a third of the book deals with political theory (or “statescraft”) as such (Havelock 1963: 3). Even more strangely, it is Plato’s attack on poetry that consumes almost the entire first half of the book.
Anselm’s ontological argument contains somewhat of the same struggle. If we follow the initial premise of the argument (God is “something than which nothing greater can be thought” is understood) to its conclusion, that this God exists in reality, we tend to see a rather big leap made by Anselm. However, what one has to understand is that Anselm was a Christian as well as a neo-Platonist. Like Plato, he saw that ideas (mental things) had a different kind of reality than nonmental things. Hence, it is vastly different to say that “the best possible” thought of a thing must exist in reality, than to say that ideas correspond to a certain kind of reality than “real” things do (Davies 1998: xii-xiii).