Natural Right and Natural History

This essay has appeared in the fall 2013 issue of the Claremont Review of Books.

 

NATURAL RIGHT AND NATURAL HISTORY

 

The Social Conquest of Earth, by Edward O. Wilson. 

Liveright Publishing, 331 pages, $27.95

Paul Gauguin's most famous painting shows some human figures set in a Tahitian landscape.  They display the human life cycle from infancy to adulthood to old age.  One corner of the painting has three questions: Where do we come from?  What are we?  Where are we going? 

To answer these fundamental questions about our human place in the cosmos, Edward O. Wilson suggests in his new book, we need to unify all our knowledge of nature by combining the natural sciences, the social sciences, and the humanities.  Traditionally, we have looked to religion, philosophy, or the creative arts to answer these great questions.  Wilson argues that these three ways to understand the human condition have failed.  This leaves science--in its quest for a complete knowledge of nature--as the only way to understand the human story. 

Wilson separates philosophy from science, because he assumes that philosophy must rely purely on introspection and logic without any of the empirical research that is done by scientists.  He thus turns away from what he said in an earlier book—Consilience: The Unity of Knowledge--where he recognized that the search for consilience, understood as the unification of all knowledge of nature,  began in Greek antiquity with Thales of Miletus and Aristotle.  Until recently, there was no separation between philosophy and science, and what we call "natural science" today was previously called "natural philosophy."  Aristotle was particularly important as a biologist who saw moral and political philosophy as a biological science.  Wilson acknowledged this in Consilience, when he identified his biological science of ethics and politics as continuing the empiricist tradition of Aristotle, David Hume, and Charles Darwin, as opposed to the transcendentalist tradition of Plato, Immanuel Kant, and John Rawls.

If Wilson's project for a Darwinian unification of knowledge is to succeed, it must revive that Aristotelian tradition of natural philosophy that includes Thomas Aquinas, Hume, and Adam Smith.  Darwin understood himself as part of that intellectual tradition, particularly in adopting ideas from Hume and Smith about the natural moral sentiments.  Even Darwin’s fundamental idea of the evolutionary emergence of life as an unintended order was derived from Smith and other Scottish philosophers. 

Recently, evolutionary moral psychologists like Jonathan Haidt have recognized that they are reviving the empiricist moral philosophy of Aristotle and Hume.  Some contemporary philosophers have embraced "experimental philosophy" as a way of putting their ideas to the test of empirical scientific research.  A few political scientists have begun to argue that their science needs to become a biopolitical science of political animals.  All of this contributes to a modern renewal of the ancient quest for a philosophical science of nature through a Darwinian natural philosophy.

We must wonder, however, whether such a Darwinian natural philosophy can be defended against the many criticisms that it faces.  Two of the most prominent criticisms are the charges of reductionism and nihilism.

Wilson’s reductionism is suggested by his statement in Consilience about reducing all knowledge to physics: "all tangible phenomena, from the birth of stars to the working of social institutions, are based on material processes that are ultimately reducible, however long and tortuous the sequences, to the laws of physics.”  This strong reductionism is so implausible that even Wilson cannot consistently embrace it.  In most of Consilience, he actually rejected "physics envy," and he insisted that biologists must "invariably encounter emergence, the appearance of complex phenomena not predictable from the basic elements and processes alone.”  He identified human beings as “emergent animals” who have capacities that are constrained, but not specifically determined by the laws of physics.  In The Social Conquest of Earth, Wilson never argues for reducing everything to the laws of physics, and he implicitly endorses the idea of the irreducibly emergent traits of life.

Biologists recognize emergent phenomena as those complex wholes with properties that we could not explain or predict from our knowledge of the parts.  The emergence of novelty occurs throughout the evolution of the universe.  Passing through levels of complexity, new properties emerge at higher levels that are not fully reducible to the lower levels.  When chemicals in the early universe formed the first living cells, that was emergence.  When the first multicellar organism arose, that was emergence.  When the human mind arose from the evolution of the primate brain passing over a critical threshold of size and complexity (particularly, in the prefrontal cortex), that was emergence.  Although the human mind is constrained by the laws of physics and chemistry, we cannot fully explain or precisely predict the workings of that mind through the laws of physics and chemistry.

One ground for emergent complexity in Wilson's science is genetic plasticity.  Wilson is often accused of genetic determinism, even though he has repeatedly affirmed genetic plasticity as allowing for individual and cultural variation.  He repeats that idea in Social Conquest in explaining gene-culture coevolution: there can be plasticity in the expression of genes that allows for a wide but still constrained flexibility in response to the cultural and individual contingencies of life.  Our human genetic nature constrains but does not determine our cultural traditions and individual judgments.

How does the coevolution of genes, culture, and judgment explain human morality and politics?  Some critics of Wilson’s project worry that any evolutionary account of morality and politics must deny that there can be any objective or fixed standards of right and wrong, which is nihilism.

Is Darwinism nihilism?  If you are a Platonist, yes.  If you are not a Platonist, no.

Most Platonists today are disappointed Platonists—people with Platonic expectations that are unfulfilled, because they accept Darwinian evolution as true, and therefore since all living forms have evolved, they cannot be eternal in conforming to Plato’s intelligible realm of eternal Ideas.  If everything has evolved, this must include moral and political order, and thus there is no eternally unchanging Idea of the Good by which we can see absolute standards of right and wrong.  Consequently, there are no moral absolutes, and we must accept moral relativism or nihilism.  Darwinism is “true but deadly” (as Friedrich Nietzsche said).  And thus these disappointed Platonists become nihilists.

But if you do not have Platonic expectations, you will not be disappointed by the Darwinian conclusion that everything has evolved, and therefore human beings have evolved.  Without the Platonic assumption that morality must be grounded in a moral cosmology, you will be satisfied with a Darwinian explanation of morality as grounded in a moral anthropology.  Even if morality has no eternal grounding in a cosmic God, a cosmic Nature, or a cosmic Reason, human morality  still has an evolutionary grounding in human nature, human culture, and human judgment.  You can say, with Leo Strauss, that “however indifferent to moral distinctions the cosmic order may be thought to be, human nature, as distinguished from nature in general, may very well be the basis of such distinctions.”  And thus in contrast to the disappointed Platonists, the satisfied Darwinians are not nihilists.

Satisfied Darwinians like Wilson see at least four mechanisms for the evolution of social cooperation and human morality: kin selection (cooperating with relatives), direct reciprocity (tit-for-tat exchanges), indirect reciprocity (having a good or bad reputation), and multilevel selection (individual selection and group selection).

The most controversial part of Wilson’s new book is that while he had previously embraced kin selection theory, he now argues against it.  Kin selection is the idea that animals have evolved to serve not only their personal fitness (the number of their surviving offspring) but also their inclusive fitness (including the fitness of their collateral relatives), and consequently animals tend to be altruistic towards closely related kin with whom they share genes.  Wilson argues that as long as multilevel natural selection (individual or group selection, or both) works generally to explain social evolution, there is no need for a theory of kin selection. 

But multilevel selection theory is not an alternative to kin selection theory; rather, they are complimentary to one another.  Kin selection cannot be the whole story, because we need to explain how unrelated individuals can cooperate.  But kin selection must be part of the story, because we need to explain the tendency for individuals to be more cooperative with close relatives than with distant relatives or strangers.  This idea was developed by Aristotle:  the natural sociality of animals originates as an extension of parental care and affiliation to ever wider groups.  Aristotle also saw that this natural sociality reached its peak among the social insects and human beings, and thus again Aristotle anticipated Wilson.

In Sociobiology, Wilson identified four pinnacles of social evolution:  the colonial invertebrates (such as the corals, the Portuguese man-of-war, and sponges), the eusocial insects (ants, bees, wasps, and termites), nonhuman mammals, and humans.  Although this sequence seems to move from more primitive to more complex forms of life, it also moves from more cohesive or cooperative societies to more discordant or competitive societies.  Colonial invertebrates can be seen as "perfect societies," because colonies consist of genetically identical individuals, and consequently they show absolutely altruistic cooperation.  But with sexually reproducing organisms, no two individuals are genetically identical, which creates conflicts of interest even among related individuals.

In Social Conquest, Wilson moves from four pinnacles of social evolution to two.  He identifies two paths to the social conquest of the earth--the insect path and the human path.  The social insects rule the invertebrate land environment.  Humans rule the vertebrate land environment.  Like the social insects, humans are "eusocial" in the technical sense that multiple generations of individuals live together, caring for dependent offspring and cooperating in a social division of labor.  While the social insects organize their colonies largely through pure instinct, with the insect queen producing robotic offspring guided by instinct, humans must organize the cooperation of individuals through personal relationships based on social intelligence, which requires navigating through a tense social network balanced between the selfish interests of individuals and the social interests of groups.  Wilson explains this tense balance in human social life between selfishness and sociality as showing the countervailing evolutionary forces of individual selection and group selection.

The unsteady balance between the individual and the group in human societies constitutes what Wilson identifies as the "iron rule" of social and moral evolution: "Selfish individuals beat altruistic individuals, while groups of altruists beat groups of selfish individuals.  The victory can never be complete; the balance of selection pressures cannot move to either extreme.  If individual selection were to dominate, societies would dissolve.  If group selection were to dominate, human groups would come to resemble ant colonies.”  So if we ask whether human beings are innately good or innately evil, we should answer that they are both.  And for that reason, "human beings and their social orders are intrinsically imperfectible.”  Here is the scientific basis for the tragic realism of evolutionary ethics. 

The ultimate mechanisms of moral evolution are enforced through the proximate mechanisms of moral emotions.  For example, Wilson identifies the human sense of honor as crucial for moral experience.  This sense of honor includes the moral emotions of indignation and resentment in response to injustice.  This sense of injustice might express what Leo Strauss called "those simple experiences regarding right and wrong which are at the bottom of the philosophic contention that there is a natural right."   It is this that allows us to derive rights from wrongs: our moral history is a history of resistance to injustice from which we derive standards of fair treatment.  But if those “simple experiences regarding right and wrong” are the purely human experiences of an animal species shaped by evolutionary history, and if that evolved human species is enduring but not eternal, do those experiences support the philosophic claim that there is a natural right?  The Darwinian natural philosopher says yes.