To continue yesterday’s discussion: Are there in fact implicit norms to which the codes of particular cultures are better or worse approximations? Judge Posner says “No.” Let's consider his first example, murder. Posner claims that the prohibition of murder is a mere tautology – that killing is wrong when killing is wrong – so that essentially it says nothing. But is this correct?
Not at all. According to the natural law tradition, the implicit norm concerning murder is that we must never deliberately take innocent human life. The norm is not a tautology, because it specifies when killing actually is wrong. Consider a difficult case: Cannibalism. It may seem that the cannibal thinks it is all right to deliberately take innocent human life, but it is much more likely that he concedes the point and denies that the people in the other tribe are human (or perhaps that they are innocent).
If I were Judge Posner, I might reply as follows: "Granted what you call the implicit norm, you have merely substituted an elaborate tautology for a simple one. A human is merely a being such that deliberately taking his life, when he is innocent, is wrong. Therefore, your so-called implicit norm translates 'It is wrong to deliberately take the lives of innocent beings whose lives, when they are innocent, it is wrong to take.' Just as before, you are saying precisely nothing."
But this hypothetical reply wouldn’t work either. The natural law tradition does not substitute an elaborate tautology for a simple tautology; on the contrary, the hypothetical reply substitutes an elaborate unproved assertion for a simple unproven assertion. For this time it takes as a given that there is no implicit norm concerning what counts as human, to which the codes of particular cultures are better or worse approximations. But again, this is not a given but the thing we are trying to ascertain.
If there really were no implicit norm concerning what is human, then it would be impossible to argue with cannibals about the matter. Experience shows that this is not true, for various cannibal tribes have yielded to the persuasion of missionaries and others. Consider too, that unless the cannibal knows deep down that the people in the other tribe are human, it is difficult to explain why he performs rituals for the expiation of sin before taking their lives.
The fact is that relativism is always more or less a fraud. No relativist ever applies his relativism consistently; either he is a selective relativist (that is, a selective moralist), or else a smokescreen artist -- using relativism as cover for a pet moral theory that pretends to be something else. Judge Posner is exception in one respect only: He is both a smokescreen artist and a selectivist.
As to his being a smokescreen artist: Posner’s own pet moral theory is "adaptationism," the view that the promotion of a society's subjective goals is an objective good. In his own words, "Relativism suggests an adaptationist conception of morality, in which morality is judged nonmorally -- in the way a hammer might be judged well or poorly adapted to its function of hammering nails -- by its contribution to the survival, or other goals, of a society." By saying that this judgment is nonmoral, Posner pretends that he is not offering a moral theory – that promoting a society’s subjective goals is not an objective good. But let us be serious. Either it is rationally appropriate to promote these goals, or it is not. If it is, then it is an objective good. And if it is not, then it is he, not the natural law thinker, who is offering a tautology: We promote those goals which we do, in fact, promote.
As to his being a selectivist: Upon examining his record, we find that Posner doesn't really believe in adaptationism either – and on the occasions when he abandons his adaptationism, he abandons the facade of relativism too. Consider for example the line of moral reasoning advanced in his dissenting opinion in Hope Clinic v. Ryan (1999), a case concerning partial-birth abortion. In view of the fact that large majorities oppose this gruesome practice, adaptationism would bid him submit to the "social goal" of ending it. Instead he advanced a variety of arguments as to why this social goal was wrong, and the majority wrong to have held it. This may be a loathsome moral view -- but it is a moral view.