Anslem's argument is sound.

[SteveII]

You think "greater" is subjective because you are confusing the fact that God is the greatest concievable being with our descerning what properties a GCB must possess. These are not the same thing and the former does not depend on the latter.

Since this is not what I think, all this shows is that you haven't understood my argument.  Your general complaint here seems to be that I am confusing our imperfect knowledge of the facts of the matter with the belief that this entails that there is no fact of the matter.  But this is completely wrongheaded.  My argument does not hinge upon what we don't know but rather hinges upon what we do know, namely that there are no objective values.  Without any values by which we can rank one thing as objectively greater than another, the concept of greatness becomes vacuous.  It's not that we have an imperfect understanding of what constitutes greatness, the problem is that we have perfect knowledge of what it does mean, objectively it doesn't mean anything.  It isn't that we are confused about what the term 'greatest conceivable being' refers to -- we know what it refers to because it doesn't refer to anything at all.

A debate about what properties are great-making does not imply that there is no objective truth about the matter. In his debates and Q&As, WLC uses the example of Timelessness. Is it greater to be timeless or in time? That is not clear to us. But that does not imply that there are no great-making properties or that the concept of a CGB is subjective. 

You're right.  A debate about what properties are great-making does not imply that there is no objective truth about the matter.  It's the fact that there are no objective values which implies that there is no objective truth about the matter.  This is simply an example of ignoratio elenchi on your part.

An omniscient mind could certainly rank value of a property or ability on a better-than scale because it could consider all logically possible scenarios at once. Therefore maximal greatness can be know by an omniscient mind and therefore 'value' is not subjective. 

It could be the case that some properties are not great-making on their own, but are a result of or linked to or limited by some other property. For example, omniscience does not entail knowing all things because there are some propositions not possible to know (like knowing what virtuous feel like). A limit imposed by a superseding great-making property. So, it makes no sense to ask is it greater to have experienced virtue than not--because it is not a logical possibility.

What on earth are you babbling about?  Of course experiencing virtue is a logical possibility.  What you seem to be trying to say is that it is not possible to be all good and to also experience virtue.  I agree.  That was the whole point in introducing the subject, namely that the greatest possible being could be all good, or experience virtue.  It was brought up to show that there may be aspects to being morally imperfect which are preferable to the advantages of being morally perfect.  The choice between the two is purely a matter of personal preference, thus undermining your claim that being morally perfect was necessarily better than being morally imperfect.  It was simply an example to show that you haven't in any sense demonstrated that being morally perfect is greater than being morally imperfect.  Objective facts cannot settle that question as it is purely a matter of preference. Regardless, my point was simply to show that depending on what one subjectively values, your claim was not necessarily true.  As a matter of necessity, moral perfection is not greater than moral imperfection because the term 'great' is not an objective descriptor.  Your claim is false, ultimately, because objective values do not exist.

You understood what I was saying perfectly. Again, an omniscient mind would be able to assess a better-than value. I think is perfectly clear even to a mortal mind, that being morally perfect is better than, in the aggregate, being morally imperfect because there are far reaching consequences to being imperfect that more than outweigh the occasional advantage. Moral perfection is an all or nothing property so therefore an aggregate assessment is the only possible one.