Does an ethics based in evolutionary psychology rest on a naturalistic fallacy?

Thomas de Zengotita makes the case in an article entitled “Ethics and the Limits of Evolutionary Psychology”  (Spring 2013, Hedgehog Review)

In After Virtue, Alasdair MacIntyre offers a hilarious portrayal of philosopher G. E. Moore at Bloomsbury convincing his enraptured audience (it was not difficult) that their particular tastes in art and love reflected quasi-platonic values to which their exquisitely refined sensibilities gave them special access.1 While Moore’s positive claims in Principia Ethica (1903) cannot survive MacIntyre’s withering caricature, Moore’s own critique, exposing a “naturalistic fallacy” in the work of predecessors as diverse as Herbert Spencer and Immanuel Kant, holds up well. This essay will apply it to efforts by evolutionary psychologists like Steven Pinker and Jonathan Haidt to reduce the ethical dimension of human existence to the vicissitudes of natural selection and genetic programming…

After summarizing their work briefly, Zengotita lets it loose:

No matter how advanced the natural science—the naturalistic fallacy—the assumption that something is morally good because it is natural—is philosophically secure. This fallacy is exposed when any definition of good offered by an ethical naturalist is subjected to a particular linguistic test. For example, when hedonism tries to define good by claiming that “pleasure is good,” the sentence itself is obviously saying something other than “pleasure is pleasure.” The two sentences are not synonymous, therefore good and pleasure are not identical. More broadly, given the claim that “Action X is good because the genetic program that triggers it, and our approval of it, was naturally selected for,” one can still ask whether it is good to do what we are genetically inclined to do. That is, asking that question still makes sense because—even using examples favored by evolutionary psychologists—the answer would appear to be: sometimes yes (help a friend) and sometimes no (kill the “other”).

It comes down to this: we cannot find truly ethical guidance in a nature shaped by evolution. Natural selection is random—random as to the mutations that produce variation, random as to the accidents of circumstance that make one variant adaptive and another fatal. Natural selection may indeed be responsible for something like a “mother instinct” that inspires tender mammalian behaviors of which we all approve. But natural selection may also be responsible for our instinctive tendency to fear what is strange and attack what is feared, thus contributing to the pageant of slaughter that has been human history. Ethical thought must take into account what Darwinian nature has made of us, and political provision must be made for that. But nothing ethical per se—nothing good or bad or even meaningful is to be found there.

Zengotita then employs Wittgenstein to delineate understanding from explanation:

The claim is that you cannot understand what it means to be human, what it is to be human, by way of science. Neurologists of the future may map brain activity so precisely that they will someday be able to read out what a person is consciously experiencing from that map—but the map will never be conscious experience. It can help explain a conscious experience, but only a person can understand it. Nature can only be explained; humanity can be understood, and understanding is a matter of meaning.

This is sounding much like Roger Scruton on the limits of scientific method ( which isn’t surprising, given that Scruton says his greatest influences are Kant and Wittgenstein).

Scruton and Zengotita both take up a phenomenological argument for knowing right from wrong based on the concept of the embodied human person – wrongs are various degrees of violations of things that can be said to be “mine” – all the way up to embodied intentions of a religious or political group. He ends with a great quote by Wittgenstein from “The Lecture on Ethics”, 1929:

But all along the continuum, from arrangements of hearth and home to the altar that beckons the light from on high and evokes the worldhood of the world—these arrangements are “culture” in a phenomenological anthropology, sites of the ethical aspect of conscious existence, anchors of embodied minds that can never be secure. Wittgenstein sums this up for us: “if I want to fix my mind on what I mean by absolute or ethical value…I wonder at the existence of the world.”