Westermarck and Incest Laws

I have written a number of posts on Edward Westermarck's Darwinian theory of the incest taboo, one of which can be found here.

Westermarck's theory illuminates some of the reasoning for Darwinian natural right. First of all, it provides one of the best illustrations of a Darwinian account of morality as arising from a complex interaction of genetic propensities, cultural traditions, and individual judgments. More specifically, it's an example of how this reasoning can be applied to the study of law.

Last week, I led my students in my philosophy of law class in a discussion of an article in the Harvard Law Review on incest laws in the United States. Although the author of this anonymous Note shows no knowledge of Westermarck's theory, one can see how the article's analysis would have been deepened by some application of Westermarck's theory.

The Note shows the great diversity--and even confusion--in the incest laws of the United States as they vary across states. The author proposes a new standard that would create consistency in the laws. The new standard would be based on a distinction between consensual and nonconsensual incest. Where individuals are in a "natural dependency" relationship of caretaker and dependent--as in mother and child--sex would be prohibited. But "consenting adults" would be free to engage in sexual relationships with one another. The underlying principle is John Stuart Mill's principle of individual liberty. Although this standard is unlikely to be enacted in law, it does point to the need for clarification of our incest laws.

To illustrate some of the confusion in the law, consider some of the cases covered in the article. Rhode Island law permits Jewish marriages between uncles and nieces. In In re May's Estate (1953), a New York court had to decide whether an uncle and niece married in Rhode Island had a valid marriage in New York. The court upheld the marriage, because it "was not offensive to the public sense of morality to a degree regarded generally with abhorrence and thus was not within the inhibitions of natural law." The author of the Note agrees with the outcome of this case but dismisses the appeal to "natural law" as purely "subjective" judgment.

In the case of Israel v. Allen (1978), the Colorado Supreme Court struck down as unconstitutional a statute that prohibited marriage between siblings related by adoption. The parents of the married couple in question had married when the children were teenagers. The court argued that biologically unrelated people are less likely to produce children with genetic defects due to inbreeding. Consequently, the marriage of adoptive siblings doesn't produce the same "natural repugnance" or "moral condemnation" as a marriage of people who are biologically related. Moreover, in this particular case, there was no evidence that the adoptive siblings had ever lived together in the same household. Again, the author of the Note accepts the outcome of this case but scorns the reasoning in the decision. The court's reasoning is said to be confused because it tries to establish some standard of what counts as an acceptable family, but in this case these adoptive siblings both are and are not members of the same family.

Applying Westermarck's theory would help us to understand what is going on here. When children are reared in the same family from an early age, they are naturally inclined to feel a sexual aversion towards those with whom they have been reared. This propensity to learn such an aversion is probably the consequence of an evolutionary history to favor behavior that is less likely to result in inbreeding that reduces fitness. This is largely an unconscious psychological process. But it can also be reinforced by conscious reasoning insofar as societies become aware of the problems of inbreeding.

We can predict that our moral repugnance will be strongest towards incest within the nuclear family, which explains why all states in the United States prohibit the marriage of full-siblings and between parents and children. But we typically feel less abhorrence towards the marriage of step-relatives who have not grown up together. And we disagree in our reactions towards cousin marriages. Many states permit cousin marriages, but the majority prohibit cousin marriages. The psychology of the Westermarck effect allows us to explain what would otherwise seem to be utter confusion in the laws of incest.

How exactly we should write our laws on incest is a matter of customary traditions and deliberate choices. Our formal laws might move in the direction suggested by the author of the Note, which would give "consenting adults" a lot of freedom in deciding whom they want to marry. But we could still enforce customary social norms through social pressure even without legal coercion.

As I have indicated in a previous post on the "good eugenics" practiced by American Jews, some Ashkenazi Jews have procedures for testing children to see if they are carriers of Tay-Sachs and other genetic maladies, and then they use voluntary means to encourage their children to consider the potential risks in their choice of marital partners.

We should use legal coercion only to enforce those norms that we can all agree on as expressing our deepest moral sense about clear harms that we want to avoid. But we can also enforce the moral norms of civil society through social persuasion without formal legal coercion.

A Revised Book Project: "Natural Right and Biology"

After receiving suggestions from various people and thinking more about it myself, I now have a revised version of my book project--

NATURAL RIGHT AND BIOLOGY: A DARWINIAN HISTORY OF POLITICAL PHILOSOPHY

1. DARWINIAN HUMAN NATURE

2. ANCIENT NATURAL RIGHT: ARISTOTLE

3. MEDIEVAL NATURAL LAW: AQUINAS

4. MODERN NATURAL RIGHTS: HOBBES, LOCKE, AND ROUSSEAU

5. THE NATURAL HISTORY OF MORALS AND POLITICS: HUME, SMITH, AND WESTERMARCK

6. NIHILISM AND NATURALISM: NIETZSCHE

7. SOCIAL DARWINISM: SPENCER, HAECKEL, AND HITLER

8. PHENOMENOLOGY AND PHILOSOPHICAL BIOLOGY: JONAS AND KASS

9. LIBERTY AND JUSTICE: HAYEK, RAWLS, AND NUSSBAUM

10. OUR TRANSHUMAN FUTURE?

Obviously, writing such a book will require more than one year! But I will be able to incorporate material from some previous writing, including some of my blog posts here.

Nietzsche and "Morality as Animal"

My new book project will probably have to include a chapter on Friedrich Nietzsche, because Nietzsche was one of the first philosophers to think through the moral and political implications of Darwinian science.

Nietzsche shows two opposing positions in his responses to modern science generally and Darwinian science in particular. In his early and late writings, Nietzsche worries that the scientific teaching of evolution is "true but deadly" because it denies the transcendent norms that motivate human greatness. In his book On the Uses and Disadvantages of History for Life (1873), he warns: "If the doctrines of sovereign evolution, of the fluidity of all concepts, types and species, of the lack of any cardinal distinction between man and animal--doctrines that I consider true but deadly--are thrust upon the people for another generation with the rage for instruction that has by now become normal, no one should be surprised if the people perishes of petty egoism, ossification and greed, falls apart and ceases to be a people; in its place, systems of individualist egoism, brotherhoods for the rapacious exploitation of the non-brothers, and similar creations of utilitarian vulgarity may perhaps appear in the arena of the future."

But in Nietzsche's middle writings--particularly, Human, All Too Human (1878) and Dawn (1881)--he explains that while he rejects the possibility of the "absolute truths" assumed by "metaphysical philosophy," he affirms the "unpretentious truths" discovered through the scientific investigation of historical reality. Since "everything has evolved," and "man has evolved," everything is historically contingent, and therefore there are no eternal truths. And yet a properly historical science of evolution can discover the "unpretentious truths" of historical development. So, while human nature is not eternal, because it has evolved as the product of a historical development, we can draw historical generalizations about human beings that are true for as long as human beings exist in their present form. Although the historical knowledge that comes from science is limited and contingent, it is a genuine kind of knowledge. "True science," Nietzsche believes, is "the imitation of nature in concepts."

At the beginning of HUMAN, ALL TOO HUMAN, Nietzsche writes: "Everything essential in the development of humanity took place in primeval times, long before the four thousand years we more or less know about; during these years humanity may well have not altered very much. But the philosopher sees 'instincts' in man as he now is and assumes that these belong to the unalterable facts of humanity and to that extent could provide a key to the understanding of the world in general: the whole of teleology is constructed by speaking of the man of the last four millennia as of an eternal man towards whom all things in the world have had a natural relationship from the time he began. But everything has evolved: there are no eternal facts, just as there are no absolute truths. Consequently, what is needed from now on is historical philosophizing, and with it the virtue of modesty."

This historical science of human nature includes a natural history of morals. By Nietzsche's scientific account, morality does not elevate human beings beyond the natural world, because human morality arises from the natural evolutionary history of animal life. In Dawn, he explains: "The beginnings of justice, as of prudence, moderation, bravery--in short, of all we designate as the Socratic virtues--are animal: a consequence of that drive that teaches us to seek food and elude enemies. Now if we consider that even the highest human being has only become more elevated and subtle in the nature of his food and in his conception of what is inimical to him, it is not improper to describe the entire phenomenon of morality as animal."

Explaining "morality as animal" conforms to a Darwinian science of human beings as animals shaped by a history of natural evolution. But many human beings regard such an explanation as a degrading view of human beings, because it denies their spiritual character as elevated above the natural world by some divinely instilled longing for eternal redemption.

Nietzsche shows this same fear in his early and late writings when he worries about Darwinian evolution as "true but deadly." The religious imagery of Thus Spoke Zarathustra and the teaching of eternal return satisfy Nietzsche's religious longing for transcendence by "eternalizing" earthly life. This religious motivation in Nietzsche was seen by Lou Salome, one of his closest friends and the woman who rejected his proposal of marriage. As a skeptical free thinker, Salome agreed with Human, All Too Human and the other books from Nietzsche's middle period of writing for "free spirits." But in his later writings--particularly, Thus Spoke Zarathustra--she saw a religious mysticism that she rejected, and which she attributed to a religious yearning that Nietzsche could never overcome. This seemed to be confirmed by the fact that Nietzsche described his experience in writing Zarathustra as "inspiration" and "revelation."

In my chapter on Nietzsche, I will defend his evolutionary science of morality in Human, All Too Human and Dawn as sensible; and I will reject the atheistic religiosity of his transcendent longings as unreasonable.

"Natural Right and Biology"--A Book Project

This week, I have been celebrating my appointment as a "Presidential Research Professor" at Northern Illinois University, which will begin in July.

One of the benefits of this position is that it will allow me to take a year off from teaching in 2009-2010 to work on a new book. My thinking about this book project has been changing. But as of now, what I have in mind is a book that might be entitled Natural Right and Biology: A Darwinian History of Political Philosophy.

In Darwinian Natural Right and Darwinian Conservatism, I have defended the idea that an Aristotelian conception of natural right might be reformulated as rooted in a Darwinian understanding of human nature and human history. In this new book, I foresee elaborating this idea through a Darwinian account of natural right moving through the history of political philosophy.

My tentative sketch of chapters for this book looks like this:

1. DARWINIAN HUMAN NATURE

2. ANCIENT NATURAL RIGHT: ARISTOTLE

3. MEDIEVAL NATURAL LAW: AQUINAS

4. MODERN NATURAL RIGHTS: HOBBES, LOCKE, AND ROUSSEAU

5. THE NATURAL HISTORY OF HUMANITY: HUME, SMITH, AND WESTERMARCK

6. LIBERTY AND JUSTICE: HAYEK, RAWLS, AND NUSSBAUM

Yes, I know, it's ridiculously ambitious. But I'm going to give it a try.

Darwin at the University of Chicago's Basic Program Retreat

The Basic Program in the Liberal Arts at the University of Chicago is a "great books" program that was originally established by Robert Hutchins and Mortimer Adler in 1946. When I was a graduate student at the University of Chicago, I taught in the Basic Program for four years (1974-1978).

Twice a year, the Basic Program has a Weekend Study Retreat at the Illinois Beach Resort in Zion, Illinois. This is organized around a particular theme and set of related readings. This year's spring weekend (May 1-3)will be devoted to Charles Darwin to commemorate the bicentennial of Darwin's birth and the 150th anniversary of the publication of The Origin of Species. The assigned readings will be from the Origin of Species and The Descent of Man.

I will be giving the Friday night lecture, speaking on "Does Darwin Support or Subvert Morality?"

On Saturday, Michaelangelo Alloca will speak on "More Fun than a Barrel of Monkey Trials: Darwin's Complex Relationship with Religion," and John Melsheimer will speak on "What Does 'Species' Mean in the Origin of Species." On Sunday morning, George Anastaplo will speak on "On the Suggestive Origins of Darwin and Lincoln." Each lecture will be followed by small-group discussions.

Saturday night will be devoted to a delightful cabaret performance by Richard Milner--"Charles Darwin: Live and In Concert." Milner is an anthropologist at the American Museum of Natural History who specializes in the study of evolution and the life of Darwin. His one-man musical on Darwin's life has been performed around the world.

This should all be great fun.

Information about the program and how to register can be found at the Basic Program's website. More information about Milner's performance can be found at his website.

Insect Politics

Ant farms don't seem to be as popular today with young boys as they were when I was a boy. There were plastic ant farms that allowed ants to build their nests in containers with plastic windows so that you could watch them at work. But I preferred to use Mason jars filled with dirt.

One day, I went to my back yard to examine my ant colony, and I was terrified to see that my black ant colony was under attack from a red ant colony. The fighting was vicious. Since this was at the peak of the Cold War, I imagined that my ants were fighting off the Red Army. After a few hours of battle, my ants were completely overrun by the Reds. It was a sad day.

Years later, when I was a college student reading Aristotle, I was pleased to see that Aristotle agreed with me that ants were political animals. According to Aristotle, some animals are solitary and others gregarious. Of the gregarious animals, some are political. Some of the political animals have leaders. Leaders can help a community by directing it to its common ends, but leaders can also harm a community when they lead factions that divide it. The distinguishing characteristic of the political animals is that they cooperate for some common work or function (koinon ergon). Humans, bees, ants, wasps, and cranes are all political animals in this sense.

And yet, Aristotle explains, human beings are more political than other political animals because of the uniquely human capacity for speech. Other animals can share their perceptions of pleasure and pain. But human beings can use speech to share their conceptions of the advantageous, the just, and the good. Through speech, human beings can deliberate about the collective good. A just political community can be judged to be one that serves the common advantage of all of its members, as contrasted with an unjust political community that serves only the private advantage of its ruling group.

If we were to follow Aristotle's lead, we would have to see political science as embracing all of the political animals, which would allow us to compare human politics with the politics of other political animals. I have argued for doing that in various articles and in Chapter 3 of Darwinian Natural Right.

In identifying ants, bees, and wasps as political animals, Aristotle recognized what biologists today see as the highly social nature of the eusocial insects belonging to the order Hymenoptera. These insects live in colonies that can have as many as 20 million members. One or a few members reproduce. Most of the other members act as workers who rarely reproduce. The colony members are all female, with queens being reproductive. Males are produced only for short periods of mating. The size and complexity of these social insect colonies make them comparable to human communities.

Apparently, Aristotle did not recognize that other group of eusocial insects--the termites--belonging to the order Isoptera. In some ways, the termites are more like humans than are the hymenopteran insects, because in termite colonies, a king lives with a queen, and the workers are often both male and female, with some division of labor between the sexes.

There have been great advances in the study of insect societies. Much of this research is surveyed in two recent books--Bert Holldobler and E. O. Wilson, The Superorganism: The Beauty, Elegance, and Strangeness of Insect Societies (Norton, 2008); and Jurgen Gadau and Jennifer Fewell, eds., Organization of Insect Societies (Harvard University Press, 2009).

I argue that this research supports Aristotle against Hobbes. In contrast to Aristotle's claim that human beings were by nature political animals comparable to the social insects, Hobbes insisted on a radical separation between animal societies as founded on natural instinct and human societies as founded on social learning. Unlike Hobbes, Aristotle saw no unbridgeable gulf between animal instinct and human learning, because he thought that almost all animals have some natural instincts for social learning, and some are intelligent enough to live as social and political animals.

The organization of complex animal societies requires communication. Among human beings, the primary forms of communication are audiovisual--as in language and nonverbal signalling. Among social insects, the primary form of communication is chemical signalling. All researchers recognize the complexity of insect communication. Some--like Nigel Franks at the University of Bristol--even argue that ants engage in teaching. Other researchers--like Ed Wilson--argue that insect learning is more hard-wired genetically.

Wilson and Holldobler have identified three forces in the evolution of insect sociality--individual selection, group selection, and collateral kin selection. Through individual selection, individuals cooperate to enhance their individual survival and reproduction. Through group selection, individuals cooperate within a group to outcompete other groups. Through collateral kin selection, individuals cooperate to spread genes shared by collateral kin. Ed Wilson and David Sloan Wilson emphasize group selection as more important than collateral kin selection. But other scientists in the tradition of W. D. Hamilton emphasize kin selection.

In any case, one can see here a deepening of Aristotle's insights, because Aristotle saw political life as rooted in the extension of parental care and in the cooperation of individuals for the common good of their group in competition with other groups.

A biopolitical science bringing together Aristotelian political theory and Darwinian biology would include the comparative politics of humans and insects.

Some of the continuing debates over the evolution of insect sociality are briefly surveyed in two recent articles in Science--one by Elizabeth Pennisi (February 6) and another by Virginia Morell (March 6).

Shadia Drury on Aquinas's Betrayal of Natural Law

Shadia Drury is a professor of political philosophy at the University of Regina in Canada. She is best known for her criticisms of Leo Strauss, the Straussians, and their influence on American politics. A brief statement of her general attack on the Straussians can be found here.

Strauss and his students are commonly identified as critics of modern relativism and historicism who looked to premodern conceptions of "natural right" or "natural law" as providing enduring standards for morality and politics. But Drury argues that this is only the deceptive exoteric teaching of Straussianism. When one uncovers the esoteric teaching, one sees that the Straussians are actually secret atheists and Nietzschean nihilists who deny that there are any natural standards for morality or politics. But they see this nihilism as a deadly teaching that would corrupt human life for the multitude of human beings. Only the philosophic few are capable of facing up to the deadly truth of nihilism, and they are careful to promote the noble lies of religious belief and natural right for the many. The superiority of the Nietzschean philosophers as the creators of all values is the only enduring standard for the Straussians.

Against the secret nihilism of the Straussians, Drury argues that there really are some natural standards for morality and politics, which can be found in the tradition of natural law reasoning. But while she looks to Thomas Aquinas as providing the best formulation of this tradition, she is deeply suspicious of Aquinas's Christian account of natural law, because she sees in Aquinas's writing a religious fanaticism and an unhealthy asceticism that promotes theocratic tyranny and a gloomy denial of earthly life.

In her most recent book--Aquinas and Modernity: The Lost Promise of Natural Law (Rowman & Littlefield, 2008)--Drury lays out her reasoning for how Aquinas betrayed the promise of natural law and how that promise might finally be fulfilled by saving natural law from Aquinas's distortions.

I have written many posts on how my account of Darwinian natural right supports a reasonable version of natural law. Drury's position is similar to mine, although I stress more than she does the modern scientific grounding of natural law, and I think her polemical style of writing sometimes leads her to overstate her arguments.

The philosophic supporters of Aquinas over the last hundred years have praised him for reconciling faith and reason, for promoting a moderate view of politics that secures liberty, and for countering the life-denying attitude of Augustinian asceticism with a life-affirming endorsement of nature's goodness. Drury denies each of these claims.

While Aquinas appears to be defending human reason and the philosophic life as autonomous in a way that should not threaten biblical faith, Drury tries to show how Aquinas ultimately puts reason under the command of faith. Aquinas's fideism is evident, for example, in his praise of Abraham's irrational faith in God's command to kill his son Isaac. One can also see this in how Aquinas distorts Aristotle's teaching to conform to biblical theology. (Here Drury actually agrees with many of the Straussian commentators on Aquinas, who also stress the ways in which Aquinas must twist Aristotle's texts to fit into a biblical view of the world.)

Many of the modern defenders of Aquinas assert that his natural law reasoning supports a moderate political teaching about the need for limited government free from theocratic fanaticism. And yet, Drury argues, Aquinas actually makes clear that secular political power is subordinate to the ecclesiastical power of the Pope as directed to the highest ends--the eternal salvation of souls. That this supports theocratic tyranny is clear, Drury thinks, in Aquinas's endorsement of the Inquisition and the Crusades.

I agree with Drury that Aquinas does show a tyrannical fanaticism in his argument that the Pope has the authority to order the execution of heretics. Aquinas was a Dominican. Pope Gregory IX in 1233 gave the Dominicans the supreme authority over the Inquisition, which became for many centuries one of the most brutal exercises of tyranny in all of human history. Drury rightly criticizes Aquinas for endorsing the work of the Dominicans in the Inquisition.

But sometimes she overstates her case. She suggests that Aquinas argued for the forced conversion of Jews and Muslims to Christianity (60-64). But this is not exactly true. Aquinas said that compulsion could be properly used against heathens and Jews only to prevent their hindering the Christian faith--but not to compel their belief. Only heretics could be rightly compelled to keep the faith (see Summa Theologica, II-II, q. 10, aa. 8, 11; q. 11, a. 3). I agree with her, however, that Aquinas's support for compelling and even executing heretics manifested a tyrannical fanaticism contrary to justice and liberty. I also agree with her in lamenting that almost none of the modern scholarly supporters of Aquinas--with the exception of Josef Pieper--have faced up to Aquinas's defense of the Inquisition.

Against the tradition of the Inquisition, religious conservatives today should respect the modern Western tradition of religious liberty. In this, they follow the New Testament teaching of Christianity about rendering to Caesar the things that are Caesar's and unto God the things that are God's. After all, the Christians in the New Testament formed churches as voluntary associations of believers, and they never sought the coercive power of the state to enforce their religion. Paul stated a libertarian principle by which the Christians should enforce their religious norms on those who belonged to their churches, but should not act coercively against those outside the church. "For what is it to me to judge those outside? Is it not for you to judge those inside? But God is to judge those outside" (I Corinthians 5:12-13). This would allow churches to excommunicate heretics, but nothing more.

Aquinas is often praised for recognizing the natural goodness of life and thus steering away from the gloomy asceticism of the Augustinian tradition. But Drury correctly points out the many ways in which Aquinas continues the masochistic asceticism of Christianity. This is most evident in the scorn for sexual love and the elevation of celibacy. Underlying this attitude of self-abnegation is a tendency towards the Gnostic dualism of spirit and flesh, in which the natural goodness of human embodiment is denied. (As I have indicated in some previous posts, much of the Christian scorn for a Darwinian view of human nature comes from a Gnostic yearning to transcend the biological reality of the human body.)

Again, however, Drury occasionally overstates her point here. For example, she writes: "Aquinas claims that the man who loves his wife too much is an adulterer" (88). What Aquinas actually says is that "the man who is too ardent a lover of his wife acts counter to the good of marriage [procreation of children] if he use her indecently" (ST, II-II, q. 154, a. 8). The point here is not to condemn "the man who loves his wife too much," but to condemn the man who engages in non-reproductive sex with his wife. Still, I agree with Drury in seeing this as an unhealthy denial of the pleasures of sexual love within marriage.

Towards the end of her book, Drury lays out her reasoning for restoring the lost promise of natural law by basing it totally on reason and natural experience, without any necessary appeal to divine law or ecclesiastical authority. This would, she insists, provide an alternative to the relativism and conventionalism of much modern and postmodern thought today. While I can endorse most of what she says here, I think she doesn't go far enough in considering how modern science supports natural law by showing how it manifests evolved human nature.

At one point, in a dialogue between "Modernity" and "Aquinas," Drury has "Modernity" say: "I must admit that my love affair with science was a mistake," because she had looked to science for "secular salvation" (132).

I see no "secular salvation" in modern natural science. But I do see a rational account of nature and human nature rooted in ordinary human experience that should sustain a modern conception of natural law. Drury believes that "nature provides not only the raw materials but also the goals" for human life, and thus a modern natural law must be founded in a teleological conception of human nature (141, 146, 154, 162, 167). Although modern Darwinian science cannot support a cosmic teleology by which everything in the universe is directed to some cosmic end, it can support an immanent teleology by which living beings are directed to the ends of each species.

In explaining what he means by the "natural inclinations" or "natural instincts" underlying natural law, Aquinas repeatedly compares human beings to other animals who share some of the same inclinations as human beings. Quoting Ulpian, Aquinas declares that natural right is "that which nature has taught all animals."

Darwinian science and the evolutionary account of the natural moral sense allow us to provide a modern scientific foundation for this Aristotelian insight into the biological character of natural right.

Darwinian science can confirm the importance of religious belief as satisfying a natural desire for religious understanding. It can also confirm the social utility of religious communities in enforcing cooperative norms. And yet it also supports the need for religious liberty and the danger of theocratic power, because Darwinism recognizes the imperfections of human nature such that no human being can be trusted to exercise a presumed divine authority over other human beings.

On this blog, I have indicated my reasons for disagreeing with Leon Kass and other Straussians who scorn modern science as a threat to human morality and dignity. This should be another point where Drury and I are on the same side.

Drury has invited me to lecture at the University of Regina in October. Perhaps then we can discuss some of these issues.