I'll not get into the debate over history. What interests me more is something Sharlet says about the nature of moral absolutes and argumentation. He says:
A moral absolute can only derived from an absolute authority, beyond the realm of argument. Santorum "rejects" the very absolutes he claims to uphold by offering reasons -- i.e., the non-absolute work of human minds -- in their behalf. Once Santorum engaged in the debate over gay marriage by suggesting that one reason for opposing it was that it could, in his imagination, lead to bestiality, he abandoned the concept of a moral absolute, a truth so self-evident it requires no explanation. Unlike Santorum, an almighty Lord does not need to resort to the illustration of "man on dog" to lend authority to his decrees.What I find puzzling is the claim that anyone who believes in absolute moral truths belies that claim by offering reasons for them. To the best of my knowledge there is nothing inherent in the concept of a moral absolute that precludes reasons being offered in its defense. If, in fact, God's character is the foundation of both objective moral truths and rationality, then it shouldn't strike us odd that sound reasons can be offered in defense of the ways in which he has commanded us to conduct ourselves. To do so is not to lend authority to those moral dictates but simply to illustrate the consequences and absurdity of violating them.
Moral argument can be a means of reminding people of what they do know but which, for various reasons, they'd prefer not to keep in mind. The Bible refers to this as suppressing the truth in unrighteousness but even if one rejects the Bible as an authoritative source, reflection upon our own lives as well as those of others should make us aware of the great capacity we have for self-deception. What atheist philosopher Thomas Nagel writes about his own fear of religion in The Last Word is applicable to the question of moral knowledge:
I speak from experience, being strongly subject to this fear myself: I want atheism to be true and am made uneasy by the fact that some of the most intelligent and well-informed people I know are religious believers. It isn't just that I don't believe in God and, naturally, hope that I'm right in my belief. It's that I hope there is no God! I don't want there to be a God; I don't want the universe to be like that (p. 130).In the concluding chapter of his book What We Can't Not Know, J. Budziszewski distinguishes between those who are honestly confused about moral matters and those who would only like to think they are. The former "rarely need more than reminders and simple clarifications: reminders of the moral principles which have been shoved aside, clarifications of the ones which have been distorted." Concerning the latter he notes:
The main reason it seems so difficult to clear up honest moral confusion is that most moral confusion is not honest. People do not fall into profound error about the basics of morality by accident, and the fault never lies entirely with their deceivers. Yes, someone may put out his foot to trip them - but they shut their eyes, pretend they don't see it, and take a fall. In such cases, the reminders and clarifications which ought to clear up the error don't work, and the reason is not that they are logically inadequate, but that the one who is deceived does not wish to be undeceived. The instant his rationalization for moral wrong has been exploded, lo, he has thought of another one. Its premises may be completely opposed to the premises of his previous rationalization, but this does not bother him; any port in a storm! In fact the "any port in a storm" sort of reasoning is so common in cases of willful confusion that it provides a rule of thumb for identifying them (p. 211).Moral absolutes don't depend on arguments for their authority for in that case they would be contingent. What arguments can do is remind us of what we already know but would rather not.