I had this moment yesterday when reading a short entry from Anselm of Canterbury. I don't recall reading anything from Anselm before, and while this was just a couple pages long, I could tell I would have an extremely difficult time keeping up with him over the course of an entire book. Do you enjoy apologetics? Do you like to read the classics? What's it like for you to read a book that was written in a time very different from our own?
I'd like to lay out, as best I can, Anselm's rational argument for the existence of God.
"God is something than which nothing greater can be thought." In other words, whatever the greatest thing we can think and imagine in our minds, that is God.As I understand him, Anselm is basically saying that the greatest thing you can think of must exist both in your mind and in reality, because anything that exists in reality is greater than anything that exists only in the mind. So if God is the greatest thing we can think of, he must exist in reality, otherwise he would not be the greatest thing we can think of.
The Bible says, "The fool says in his heart, 'There is no God.'" But when this person hears the description, "something than which nothing greater can be thought", he gets a picture of that something in his mind, even though he believes that that something does not exist.
However, "something than which nothing greater can be thought" cannot merely exist in the mind, because then everything that does exist would be greater than it. If "something than which nothing greater can be thought" exists solely in the mind, then it is "something than which many greater things can be thought", which is, of course, absurd.
Therefore, it is definite that "something than which nothing greater can be thought" must exist both in the mind and in reality.
Anselm wrote this about 900 years ago. What do you think? Is it a convincing argument? Does it have a fatal flaw?