To be precise, this paper applies to WLC’s moral argument for God’s existence as follows.
1. WLC argues that God exists because objective moral values and duties exist.
2. Critics (theist, agnostic, and atheist) of WLC’s moral argument have pointed out that, according to one version of moral realism, moral truths are necessary truths. Necessary truths neither have nor need an explanation. Therefore, God isn’t needed to explain necessary moral truths and, hence, isn’t needed to explain objective moral values and duties.
3. WLC (and Mark Murphy) object to point 2 by providing counterexamples to show that necessary truths, including necessary moral truths, can have an explanation.
4. John Danaher defends point 2 against the counterexamples in point 3.
Here is the abstract:
Theistic metaethics usually places one key restriction on the explanation of moral facts, namely: every moral fact must ultimately be explained by some fact about God. The problem is that the widely-held belief that some moral truths are necessary truths undermines this claim. If a moral truth is necessary, then it seems like it neither needs, nor has an explanation. Or so the objection typically goes. Recently, two proponents of theistic metaethics — William Lane Craig and Mark Murphy — have argued that this objection is flawed. They claim that even if a truth is necessary, it does not follow that it neither needs nor has an explanation. In this article, I challenge Craig and Murphy’s reasoning on three main grounds. First, I argue that the counterexamples they use to undermine the necessary truth objection to theistic metaethics are flawed. While they may provide some support for the notion that necessary truths can be explained, they do not provide support for the notion that necessary moral truths can be explained. Second, I argue that the principles of explanation that Murphy and Craig use to support theistic metaethics are either question-begging (in the case of Murphy) or improperly motivated (in the case of Craig). And third, I provide a general defence of the claim that necessary moral truths neither need nor have an explanation.