Commenting on how atheists have responded to William Lane Craig’s moral argument, Victor Reppert writes this.

Yet, when I hear atheists talking about moral arguments, they always assume that the advocate of the moral argument is saying that we have to believe in God to lead moral lives, (and indignantly argue that we don’t have to believe in God to lead moral lives) in spite of the fact that Christian advocates of moral arguments, at least the ones I am familiar with NEVER say that. 

I agree with Reppert that many atheist debaters have misunderstood William Lane Craig’s moral argument. On the other hand, surely Reppert as a professional philosopher can recognize the over-generalization in his post. He makes it sound like all atheists “always assume that the advocate of the moral argument is saying that we have to believe in God to lead moral lives.” This is, of course, false.

It’s useful to distinguish between atheist philosophers and atheist non-philosophers. Among non-philosophers, it does seem like scientists have done particularly bad in offering a relevant rebuttal.  As for philosophers, I don’t claim that atheist philosophers have a perfect track record on this topic; see here for my summary of Craig’s debate with Paul Kurtz, where Kurtz poorly responded to Craig. But that is beside the point. Did Reppert really mean to imply that every atheist philosopher who has responded to Craig’s moral argument has misunderstood Craig? I could cite many counter-examples, but I’ll mention just one: Erik Wielenberg, author of Value and Virtue in a Godless Universe.

In his book, Wielenberg clearly demonstrates he understands Craig’s argument and offers a refutation. Why hasn’t Craig responded to Wielenberg? For that matter, if we consider theistic critics of his moral argument, why hasn’t Craig responded to Wes Morriston’s criticisms (see here and here)?

ETA: For a critique of Craig’s moral argument by an agnostic, see Paul Draper’s essay in Does God Exist? The Craig-Flew Debate. I quote a snippet of Draper’s essay on The Secular Outpost before.