The Ontological Argument for the Existence of God

I intend to post here from time to time some discussion of the Ontological Argument for the existence of God. I'm not particularly interested in this as an apologetic as it has been particularly unfruitful in this regard. For a number of years now I've had an interest in exploring the history of the argument and in pursuing the things that can be learned by studying it. Briefly, here is why I have been so fascinated by this argument:

1) It claims to be a rational proof for the existence of God
2) Its simplicity of statement but complexity of argument
3) The fact that every major philosopher has had something to say about it
4) The fact that it appears to be obviously flawed but has resisted a definitive rebuttal for a thousand years
5) It is an abstract word puzzle that resents a fascinating challenge to the logician.
6) It involves all kinds of interesting questions including the nature of existential propositions, the relationship between being and nonbeing, the nature of ideas and reality, etc.

The first statement of the argument was made by Anselm (1033-1109) and I will post that next.