William Craig’s MOVE argument is simple:

1. If God does not exist, objective moral values do not exist.

2. Objective moral values do exist.

Therefore:

3.  God exists.

One obvious atheistic objection would be to reject or cast doubt on premise (2).  If one rejects or doubts that objective moral values exist, then this argument will fail to be persuasive.

Another possible objection is to reject or cast doubt upon premise (1).  Some atheists accept moral realism, and thus believe that the non-existence of God is logically compatible with objective moral values.  I will be focusing on this particular objection to the MOVE argument.  Craig refers to this view as Atheistic Moral Realism.

Craig raises three objections to atheistic moral realism (hereafter AMR):

AMR is incomprehensible.

AMR is incompatible with the nature of moral duty.

AMR implies a fantastically improbable coincidence.

Let’s consider his first objection to AMR:

I must confess that this alternative strikes me as incomprehensible, an example of trying to have your cake and eat it too.  What does it mean to say, for example, that the moral value justice just exists?  I understand what it is for a person to be just, but I draw a complete blank when it is said that, in the absence of any people, justice itself exists.  Moral values seem to exist as properties of persons, not as abstractions–or at any rate, I don’t know what it means for a moral value to exist as an abstraction.  Atheistic moral realists, seeming to lack any adequate foundation in reality for moral values, just leave them floating in an unintelligible way. 

(WIAC, p.76)

My first thought is that Craig is being rather skeptical here, which is a good thing.  However, people who live in glass houses should avoid swinging sledge hammers around in their living room.  Whenever one makes a skeptical move (for example, making use of Occam’s Razor), it is important to avoid doing this in a biased way,  using skeptical moves against ideas that one dislikes while never making use of the skeptical move against ideas that one favors.

I’m not positive that Craig is being hypocritical here, but I strongly suspect that the sort of skeptical move he makes here could also be used to inflict serious damage to many of the beliefs that Craig holds dear.  Nevertheless, I am a skeptic, and I fully appreciate the kind of skeptical thinking that Craig appears to be engaged in here.  So, although he may be wielding a two-edged sword, one that inflicts damage to both AMR and Theism, I will ignore any possible bias and hypocrisy on Craig’s part, and only think about whether his skeptical move works against AMR.

Perhaps Craig is correct that some thinkers who accept AMR believe that justice exists as an abstraction independent of any human beings or persons, but this is NOT a logical implication of AMR, as far as I can see.  Moral realism claims that moral judgments can be true or false, and that some moral judgments are in fact true.  It is hard to see how one can get from these claims to the metaphysical claim that justice is an entity that exists independently of humans or persons.

The word ‘green’ refers to a color.  The sentence ‘Grass is green.’ makes a true statement.  In making these claims,  I do NOT imply that the color green is an abstract entity that exists independently of any blades of grass, or trees, or shirts, or houses, or any other physical objects.

Similarly, if I say that the sentence ‘It was unjust for Hitler to order the killing of millions of innocent civilians’  makes a true statement,  this does NOT imply that justice is an entity that exists independently of any human being or person.

Justice, it seems to me, is primarily an attribute or characteristic of actions, and actions can only be performed by agents or persons. Thus, justice cannot exist independently of agents or persons, because justice cannot exist independently of actions, and actions cannot exist independently of agents or persons.

I think Craig is correct in being skeptical about justice existing as an abstract entity independently of the existence of agents or persons.  If justice is, first and foremost, an attribute or characteristic of actions, then it does appear to be implausible to think of justice as an abstract entity.  However, an attribute (such as ‘green’) may be correctly ascribed to a particular entity (such as ‘grass’ or ‘this patch of grass’) without it being the case that the attribute constitutes an independently existing entity.

So, I am not persuaded by Craig’s objection here.  He may have a legitimate objection to the stated views of some particular thinkers who accept AMR, but this objection does not appear to be relevant to AMR itself.