  The latter problem arises from a dilemma posed in Plato’s Euthyphro. In this dialogue Euthyphro tries to explain to Socrates that piety is what the gods love. Socrates then asks Euthyphro whether the gods love the pious because they are good or whether the pious are good because the gods love them. To put the dilemma in terms relevant to the present context, consider the view that genocide is wrong because it is contrary to God’s will. (The argument doesn’t change if we talk about commandments or love instead of will.) We can ask of this view whether God forbids genocide because it is wrong, or whether it is wrong because God forbids it. In the latter case God’s will appears to be arbitrary or at least not based on an appropriate moral reason. For believers who regard God as supremely moral, the latter possibility would be unacceptable. In the former case, however, God’s will would be based on the wrongness of genocide, conceived as being separate from and logically prior to the concept of God’s will. Hence, in this case the appeal to God’s will does not provide an answer to the skeptic, but rather presupposes that we already have an answer. In sum, unless we are prepared to suppose that what God wills, loves, or commands has no moral basis, the attempt to base the possibility of moral knowledge on knowledge of God’s will or love or commandments is, like Euthyphro’s explanation of piety, viciously circular. (For discussion of other versions of the objection, see Chandler 1984 and Westmoreland 1996. Also see the entry on  theological voluntarism.)