Loftus continues his commentary on ethics by saying that "Michael Martin argues that relativism 'is compatible with complete agreement on all ethical matters’". (pp. 40-41)
This statement seems absurd because moral relativism assumes that different groups of people are going to adhere to their own ethic which means there won’t be complete agreement between them on how to act morally. In fact, the study of moral relativism is the study of the descriptive, normative or meta-ethical variations between cultures. Even if there is a sense in which Martin is right, it would further illustrate how there can be no comprehensive ethic outside of an absolute morality.
Loftus quotes Michael Shermer in that "moral principles, derived from the moral sense, are not absolute, where they apply to all people in all cultures under all circumstances all of the time. Neither are moral principles relative, entirely determined by circumstance, culture and history. Moral principles are provisionally true-that is, they apply to most people in most cultures in most circumstances most of the time." (p. 41)
First, moral principles cannot be derived from the moral sense. In order to make a moral judgment on an action, there must be an appeal to an extreme, otherwise known as an absolute sine qua non exists outside of a transcendent moral anchor. The “moral sense” that Shermer refers to is clearly not a transcendent moral anchor. Second, in his appeal to moral principles, he must necessarily agree that they in fact are ubiquitously applicable. Otherwise, there is no moral prescription. Third, he logically negates his own relativist statement about morals being provisionally true by making an absolute statement. He is saying that the moral provisionism is absolutely true for all. The idea that morals are provisionally true is itself an absolute, ubiquitous ethic which means he really doesn’t see things as provisional anyway. This is the common mantra of the bourgeois postmodernist; “be tolerant of everything except Christianity”. Furthermore, making an absolute statement that is supposedly true for all (relativism is right) requires smuggled-in autocracy. Where did the person making the statement get the authority to apply a ubiquitous ethic? They never say.
In the end, it’s difficult to ascertain what Loftus is advocating. He seems to be pointing to utilitarianism but does he espouse the "act" or "rule" variety? Also, he seems to be advocating a subjective preference utilitarian theory of value but he doesn't specify prescriptive or descriptive rationality.