Luke Muelhauser confronts William Lane Craig with the inconsistency between his divine command interpretation of morality, according to which things are moral or immoral as solely determined by God’s calling them as such, on the one hand, and his insistence that in this way God is the source of “objective morality”:
But let us say you are using the term ‘objective’ in a different sense than most of the moral philosophers I have read. You do clarify your meaning with an analogy about Nazis. You say that divine command theory is ‘objective’ because even if the Nazis had won WWII and brainwashed everyone into believing that anti-semitic violence was moral, it would still be true that anti-semitic violence is immoral, because it is disapproved of by God. Thus divine command theory is ‘objective.’ Perhaps you use ‘objective’ to mean something like ‘grounded in something other than the attitudes or nature of persons who are primates.’
But if so, I’m confused by an argument you give in favor of the existence of objective moral values. You often appeal to a common intuition that objective moral values exist, but I’m not sure many people have an intuition concerning the kind of objective moral value you describe above.
Consider, for example, a possible world much like our own, except that Earth is visited by a massive, one-of-a-kind powerful alien, and many people define moral value by reference to the attitudes of this alien. Putting aside the question of how people are allowed to define moral terms, and ignoring that this possible world does not exist, it seems that such a moral theory would be ‘objective’ in your sense. Why? Because if Nazis in this possible world brainwash everyone into believing anti-semitic violence is moral, it would still be the case on this moral theory that anti-semitic violence is immoral, for the giant alien disapproves of it.
And if that is all you mean by ‘objective’, then I don’t think many of us have an intuition that morality is objective in THAT sense. I suspect those of us who believe in objective morality have intuitions about a more robust sense of objective moral realism that does not ground moral value in the attitudes or nature of particular persons. (Such theories of robust objective morality are offered by ethical non-naturalism, Cornell realism, and so on.) This even includes many Biblical authors, who seem to assume robust objective moral realism rather than divine command theory (see Ps. 34:9, which seems to non-tautologically predicate goodness of Yahweh; Ps. 58:2, which questions the goodness of the gods; Ex. 33:14; Gen. 18:25; Ezek. 20:25; and many others).
A few of Luke’s commentators make a game effort to answer the objection. I recommend reading through them.
Thanks to Zach for the heads up.