I. The Category Mistake: Moral Psychology Is Not Moral Philosophy
The Vulgar Moralist remarks that
[t]he primacy of genetics and emotions in morality is somewhat controversial – but at this late hour, not all that much. On the one side stands 2,500 years of moral philosophy exalting the 'rational life'; on the other, a growing body of research." Thus, the moral philosophy that exalts the rational life stands in opposition to the body of research that has illuminated the emotional and genetic factors that effect the moral choices of human beings.This opposition is founded upon a category mistake. The question of why people believe in certain moral principles belongs do the discipline of moral psychology; the question whether those moral principles are true belongs to moral philosophy. Obviously people can believe in true things for false reasons: just because one's belief that Caesar existed is predicated upon the belief that the television show "Rome" is a documentary does not make the historical arguments any less valid. Further, people often believe in true things on the basis of beliefs that don't have much to do with the truth or falsity of the subject: people might believe in relativity theory because Stephan Hawking believes in it, but the fact that Hawking has an opinion on the subject doesn't bear on the truth or falsity of relativity theory. The process of evaluating the truths of beliefs is distinct from the process of evaluating how different people come to their beliefs.
The Vulgar Moralist's category mistake is, therefore, at the same time an ad hominem argument, because it focuses on the person making an argument in a way that ignores the argument itself.
II. Nature and Teleology
The Vulgar Moralist answers the question of whether human nature negates teleology by saying that
[g]rounding morality in human nature strips away any purpose inherent to the world: but not, let it be noted, human purpose while acting in the world. Every morality is erected on ideals. Every ideal is an unattainable model of behavior. Every good person is inching toward an ideal vision of himself: that person-as-he-could-be.There are a few obvious problems with this answer. The assertion that "[e]very morality is erected on ideals" is vague enough that it doesn't mean much of anything. Or again, the assertion that "[e]very ideal is an unattainable model of behavior" is manifestly false: many ideals (such as the ideal that people ought not murder each other) are more attained than not.
The more fundamental problem appears to be an unfamiliarity with what an Aristotelian means by nature. As I've written about before, "nature" for an Aristotelian does not mean primarily the picture we get from the physical sciences, nor the geographic locations that are relatively free from human dominion. Nature is the intrinsic principle of motion in a thing (as I've also written about before). A tree is natural while a wooden statute is not, because the wooden statue does not move itself from within -- what form it has is the result of external force -- whereas the tree does move itself.
This internal principle of motion strives towards realizing the form proper to the thing. A tree, provided it has all the nutrients and sunlight it needs, will of its own accord grow and blossom. Human beings too have an internal principle of motion: no one imposes growth on them from without. But human beings additionally possess the capacity of reason, the ability to direct their activity towards those things perceived as desirable. The inquiry into what constitutes human flourishing and what activities tend toward this flourishing is the science of ethics proper.
III. Final Thoughts
Several aspects of the Vulgar Moralist's arguments are particularly outlandish. For instance, the Vulgar Moralist argues:
In a liberal democracy, there will always be a plurality of contradictory religious beliefs, and standing on one to the exclusion of the others – that is, absolutely and uncontingently – will eliminate all common ground.This isn't even plausible prima facie. There are plenty of examples of generally accepted moral propositions: most people in the United States believe that murder, for example, is wrong. Further, if a certain political system disintegrates a society's moral fabric, that seems a good reason to reject it as a bad political system. If liberal democracy creates moral chaos, then down with liberal democracy.
And finally, when one boldly declares that X is without a rational basis, then one ought at least to deal substantively with the best argument for the rational basis of X. For example, if I argue that Godel's theorem is indemonstrable by mathematical methods, I had better demonstrate that I have a grasp of the basic methods of mathematics, of the theorem itself, and of the arguments surrounding it. Or if I assert that no evidence exists that Al-Queda is involved with terrorism, I ought at least deal with the arguments for the other side. Likewise, when the Vulgar Moralist declares that no rational basis for morality exists, one would expect that he engage seriously and substantively with the arguments to the contrary.