Wednesday, July 31, 2013

Debating Darwinian Liberalism: Dilley's Syllogism

How many evil consequences of Darwinian science can you imagine? 

Until recently, I could imagine quite a few.  But now that I have read an essay by Bruce Gordon, I can think of hundreds of evils coming from Darwinism.  I don't have room here for Gordon's complete list.  So I'll give you a short sample.  According to Gordon, the "cultural poison of Darwinian philosophy" leads to the following:  hedonism, narcissism, totalitarianism, eco-terrorism, fetal farming, state-enforced active euthanasia, Marxism, fascism, nihilism, "hollow men," "ceding national sovereignty to effete international bureaucracies," multiculturalism, affirmative action, "central government planning of all aspects of life," "cultural guilt and self-loathing," and "a Hegelian religion of the state as the immanent unfolding of the Absolute Spirit."  The final outcome of all this is "that the noonday sun of Western strength is spent and will fade into the twilight of an ignoble dissolution . . . our hope must fade, and night descend" (175-83). 

Wow.  If you're like me, you had never imagined that so much evil stuff could come from the idea of Darwinian evolution.

So how exactly does Darwinian science bring the descent of human civilization into a night without hope and rule by "effete international bureaucracies"?  To answer that question, you'll need to read the book in which Gordon's essay appears--Darwinian Evolution and Classical Liberalism: Theories in Tension, edited by Stephen Dilley and newly published by Lexington Books. 

Most of this book is a criticism of my argument that Darwinian evolutionary science supports classical liberalism.  Of the thirteen contributors to the book, eleven criticize my position, one supports one part of my position, and one generally supports my position.  Here are the eleven critics: Stephen Dilley, Benjamin Wiker, Peter Augustine Lawler, Jay Richards, Angus Menuge, John G. West, Logan Paul Gage, Bruce Gordon, Richard Weikart, Roger Masters, and Michael White.  Shawn Klein agrees with me only partially. Timothy Sandefur is the one hero who generally (but maybe not totally) agrees with me.

This post is the first in a series of posts in which I will respond to this book.  I begin with the argument that seems to be embraced by the first nine critics in the above list, and I will call the argument Dilley's Syllogism, because it's stated by Dilley in his introductory chapter.

Although Dilley does not state it in exactly this way, his argument seems to be this:
Classical (Lockean) liberalism is founded on Christianity.
Darwinism denies Christianity.
Therefore, Darwinism denies classical (Lockean) liberalism.
Consequently, the nine critics are proponents of what they call "Christian classical liberalism" or "theistic classical liberalism" (19, 23,158-59).  They also identify this with the liberal political thought of the American founders, and so they defend "the rich theistic classical liberalism embodied in the American founding" (159).  I have inserted "Lockean" into the syllogism because the first nine critics generally appeal to John Locke as "the quintessential classical liberal" (198), although they also often identify Adam Smith as a paradigmatic classical liberal (9-10, 13-14, 158).

The nine critics say that they are attacking "Darwinian conservatism," which "integrates a Darwinian conception of human nature with the essentials of classical liberalism, drawing on the work of Locke, Smith, Hayek, and others" (10).  They identify the most prominent proponents of Darwinian conservatism as me, Thomas Sowell, Robert McShea, James Q. Wilson, Michael Shermer, and Francis Fukuyama.  Most of their attacks, however, are directed at me.

The nine critics don't explain clearly what they mean by Christianity or how exactly specific doctrines of Christianity lead to classical liberalism.  They sometimes refer to the "God of the Bible," the "biblical worldview," or "Judeo-Christian orthodoxy," which suggests they are embracing both the Old Testament and the New Testament, both Judaism and Christianity (19-20, 26, 154, 158-60, 171, 189, 193, 198).  Does this exclude Islam?  Gordon argues that the "Christian worldview" in its purity excludes "Islamic religious identity" (196).

The only doctrinal teaching of the Judeo-Christian tradition that they mention is the idea of imago Dei: "In very broad strokes, this interpretation emphasizes both the dignity of human beings--as creatures fashioned in the imago Dei--and their depravity, having been subject to Adam's Fall" (11).  It is the equal dignity of all human beings as created in God's image that they see as the foundation of classical liberalism, and so if Darwinism denies this imago Dei doctrine by teaching that human beings were "created from animals," Darwinism thereby denies classical liberalism (198) and promotes all the evils listed by Gordon that are bringing about the complete collapse of Western civilization. 

This summarizes the famous "Wedge Document" of the Discovery Institute in Seattle, which laid out the plan for attacking Darwinian evolution and advancing "intelligent design theory" as a way of saving Western culture from the corrosion of scientific materialism.  Most of these nine critics have been associated with the Discovery Institute.

Although the nine critics generally agree that Christianity dictates the classical liberalism of Locke, they sometimes contradict themselves on this point.  For example, Benjamin Wiker refers to Locke as a Deist and implies that Locke appealed to Christianity only for the sake of persuading "the less enlightened" (44).  Wiker also identifies Hobbes as the true "father of modern liberalism" and explains: "In Hobbes we see the shift from morality rooted in natural law as defined by God and embedded in a teleological view of nature in which human moral goodness is defined by the perfection of our God-given nature, to morality entirely rooted in this-worldly passion and self-preservation embedded in an entirely non-teleological view of nature and human nature."  Moreover, he indicates, "this seems a great anticipation of, and hence entirely compatible with, Darwin's account of the evolution of morality" (45-46). 

In his book Moral Darwinism, Wiker argues that Locke was a Epicurean materialist who promoted a science of hedonism that would later be fulfilled by Darwin.  He also argues that insofar as Locke's ideas crept into the American founding, they became the seeds of moral corruption in American political life.  Oddly, Wiker doesn't mention this in his contribution to Dilley's book.

Do the nine critics really agree on Dilley's Syllogism?  I am not sure.  But I will assume that they do, because this gives me a coherent line of reasoning to which I can respond in my forthcoming posts.

Although I disagree with the nine critics in many ways, I agree with some of their points.  Peter Lawler and I are not far apart.  And I will indicate my agreement with Jay Richards, who shows that I have been wrong in suggesting that it's inconsistent to affirm free markets and deny Darwinian evolution.

Dilley's book should be read alongside Darwinian Conservatism: A Disputed Question, edited by Ken Blanchard (2009).  This book reprints the text of Darwinian Conservatism, followed by critical responses from eight authors, including three of the authors in Dilley's book (Lawler, West, and Sandefur).  This book concludes with a response from me and a good essay by Ken Blanchard on the Aristotelian character of Darwinian conservatism ("Natural Right and Natural Selection").

Thursday, July 25, 2013

The MPS in the Galapagos (14): The Evolution of Religious Belief

Originally, Pascal Boyer was to lecture at the MPS conference on the evolution of religious belief.  He teaches in the Departments of Psychology and Anthropology at Washington University in St. Louis.  In one short summary of his evolutionary theory of religion, he concludes: "The mind has myriad distinct belief networks that contribute to making religious claims quite natural to many people."

Unfortunately, Boyer lost his passport, and so he could not travel to the Galapagos.  Leda Cosmides agreed to speak in his place, followed by Father Robert Sirico, the founder of the Acton Institute for the Study of Religion and Liberty.

Cosmides began by suggesting that Boyer's evolutionary account of religious belief is a Hayekian view of how ideas spread--those that are more successful in conforming to the human mind tend to prevail.  Boyer explains how ideas about the supernatural arise as byproducts of normal cognitive functioning.

According to evolutionary psychologists, the human brain has evolved cognitive functions for detecting intelligent agency and human artifacts, and consequently the brain is naturally inclined to find intelligent agency in whatever looks like it was intentionally designed.  This makes it easy for us to belief in supernatural agents.

Cosmides insisted that this theory of the cognitive evolution of religious belief remains neutral on the issue of whether God exists.

To support this, she could have mentioned the work of Jesse Bering and Justin Barrett.  As I have indicated in some previous posts here and here, Bering and Barrett agree in accepting the evolutionary origin of religious belief.  But while Bering is an atheist, Barrett is a Christian.  A Christian psychologist like Barrett can believe that human beings have a naturally evolved inclination to believe in God, because God has created them that way, using an evolutionary process.  By contrast, an atheist like Bering can see the evolutionary explanation of religious belief as showing that such belief is an illusion.

Following Cosmides, Father Sirico spoke on "Hayekian Social Theory and Religious Truth."  His main idea is conveyed in the last two sentences: "The battle to see the religious mind as an integral part of the social process is part of the same battle to regard the freedom of the marketplace through which economic knowledge develops and which must be allowed to work itself out without the intervention of 'scientists' who purport to have more knowledge than the human experience itself can provide.  However implausible it may seem, the development of society and the development of faith have more in common than might be first supposed" (18-19).

While wondering why Hayek's writing shows so little overt discussion of religion, Father Sirico argued that Hayek's understanding of social order as emerging best through spontaneous evolution is applicable to the evolution of religious belief.  He made three points in support of this claim.

First, he noted how often Hayek cited religious thinkers like Lord Acton and the late scholastics of the middle ages, who supported the idea of social order as the "result of human action but not of human design."

Second, Father Sirico argued that Hayek's condemnation of rationalist constructivism and scientism could apply to the rationalism of the "New Atheists," who try to dispose of all inherited religious beliefs and then reconstruct all our beliefs as personal constructions of reason.

Third, he argued that Hayek's account of how social order arises from a gradual evolutionary development could also apply to the development of religious doctrine.  The doctrines of Christianity arose through many centuries of experience as an evolutionary process of adaptation and refinement.  He found this best expressed in some of the writing of John Henry Newman.

Father Sirico's most interesting thought on this third point was how religious fundamentalism took a constructivist approach similar to socialism.

As I listened to Father Sirico, I wondered whether Boyer would agree with him that religious belief arises from the social marketplace, in which some religious beliefs by trial and error are found to be better adapted to the human mind than are others.  This seemed to be what Cosmides meant when she said that Boyer's evolutionary explanation of religious belief was Hayekian.

In the question and answer period after the two lectures, I asked this question: Do the two of you agree that atheism is contrary to evolved human nature?

They both said yes.  Cosmides said that atheism is not naturally adapted to evolved mental capacities.  She also indicated that she disagrees with Richard Dawkins in his aggressive attacks on religion.

Father Sirico said that the methodological naturalism of many scientists is contrary to natural human experience.

During this discussion period, Father Sirico objected to Hayek's social evolution as lacking a telos.  He said that we need a standard in human nature to set the telos for judging cultural traditions.  He used the example of the multiculturalist support for female circumcision (or genital mutilation) as showing the stupidity of cultural relativism without a natural standard of judgment.

I agree with this.  I would say that there is an immanent telos in human evolution insofar as the 20 natural desires of evolved human nature set a standard by which we can judge societies as better or worse in satisfying those natural desire, including the natural desire for religious understanding.

In some previous posts, I have used the example of female circumcision to illustrate this, just as Father Sirico did.  This is what I mean by "Darwinian natural right."

These lectures concluded the Mont Pelerin Society conference in the Galapagos on "Evolution, the Human Sciences, and Liberty."  As you can see by my 14 blog posts, this was a remarkably stimulating conference in helping me think about the moral, economic, political, and religious implications of Darwinian evolutionary science.  Combined with my "evolutionary tour of the Galapagos" during the preceding week,  this gave me much to ponder as I continue to develop my argument for Darwinian liberalism.

The MPS in the Galapagos (13): The Human Mystery and The Limits of Scientific Materialism

At the MPS conference, we had spent most of the week talking about how science--particularly, evolutionary science--explains human social life.  But at the end of the week--the afternoon of June 27th--we heard lectures that raised questions about the limits of such scientific explanations.  We were invited to wonder whether human life in the cosmos is mysterious in ways that point beyond scientific materialism to some immaterial or spiritual reality.

This began with James Le Fanu talking about "The Problem with Science."  He is a medical doctor, a newspaper columnist, and a historian of science and medicine in England.  He is the author of Why Us? How Science Rediscovered the Mystery of Ourselves (2009), which seemed to be the basis for his lecture.  He has summarized much of his argument in an article for Prospect magazine.

As suggested by the title of that book, his theme was "the mystery of ourselves" as transcending the materialist explanations of modern science.  I was reminded of similar thoughts expressed by people like Walker Percy, Leon Kass, and Wendell Berry.

Le Fanu argued that in recent years we have seen what John Horgan called "the end of science":  modern science has answered many of the "big questions," but the "big questions" that remain unanswered are beyond science.  For example, debates in cosmology raise questions about how the universe arose from nothing, or whether there are multiple universes.  The completion of the human genome project has not deciphered the "Book of Life," as was originally hoped, because the complexity of genes interacting with one another, with epigenetic factors, and with the physical and social environments of the organism has proven too complex to explain precisely.  Similarly, neuroscience shows us that everything is connected to everything else, even in the simplest tasks, and we cannot explain how or where all this information is brought together into a unified sense of consciousness.  Indeed, our introspective experience of self-consciousness is itself beyond neuroscience because it is not observable except as a private experience.

Many neuroscientists assume that brain = mind.  But there is no warrant for this assumption because the human mind is not fully explicable in purely material terms.  Our mental and moral experiences of free will, consciousness, and self-identity cannot be reductively explained as mechanistic products of neural activity.  Human thought and imagination are in principle immaterial and thus not explainable through the materialist naturalism of science.

Some people have wondered whether Le Fanu is a creationist who denies evolution.  He has written a blog post in which he explains that while he accepts Darwin's theory of evolution, he thinks it cannot fully explain those mental, moral, and spiritual capacities of human beings that make them unique.  He accepts much of the evidence for evolution by natural selection--such as the adaptive radiation of Darwin's finches in the Galapagos.  But he doubts that this can explain everything about living beings, especially human beings.

As I listened to Le Fanu, I was reminded of David Lack.  Le Fanu was lecturing at the Charles Darwin Conference Center in Puerto Baquerizo Moreno on Wreck Bay in the island of San Cristobal.  In December 14, 1938, Lack landed on Wreck Bay to begin his famous study of "Darwin's finches," which would provide evidence for Darwin's theory, evidence that Le Fanu accepts.  But some years later, Lack wrote a book--Evolutionary Theory and Christian Belief--in which he argued that although evolution was a scientific fact, it could not explain everything about human beings: "Science has not accounted for morality, truth, beauty, individual responsibility or self-awareness, and many people hold that, from its nature, it can never do so, in which case a valid and central part of human experience lies outside science" (114).

I am not sure, however, that Le Fanu really does accept the truth of evolution, as Lack did, because I have noticed that the speech Le Fanu gave at the MPS conference was also given in Seattle and broadcast as a podcast sponsored by the Discovery Institute, which is the leading promoter of "intelligent design theory."  If Le Fanu is advancing "intelligent design" as superior to evolutionary science, he should have indicated that at the MPS conference.  If he had done that, he would then have had to explain the content of his theory:  Exactly when, where, and how did the Intelligent Designer create all forms of life?  Like the advocates of intelligent design, Le Fanu employs a purely negative style of argumentation--criticizing scientific materialism as inadequate for explaining things but offering no alternative explanatory framework.

At the end of Why Us? Le Fanu calls for a "new paradigm" in science.  Although he is vague about what this would be, he is clear that it would be devoted to "restoring man to his pedestal" and to "a renewed interest in and sympathy for religion" (258-59).  From this would emerge a new respect for intelligent design reasoning, he suggests, and he cites Michael Behe as the best theorist of intelligent design.  He thinks the clearest evidence for intelligent design is the genetic code: "just as it requires human intelligence to produce anything with a high information content, whether books or dictionaries, music scores or compact discs, so by analogy it would be reasonable to infer that it would require a 'higher intelligence' to formulate the genetic code" (259).  (In my debates with Behe and other intelligent design theorists, I have pointed to the equivocation in this anthropomorphic analogy: although human intelligent design is known by ordinary experience, divine intelligent design is not.)  He then concludes the book by pointing to Marx, Freud, and Darwin as the three great proponents of scientific materialism, and then predicting that just as Marx and Freud have been proven wrong, so will Darwin.

This clearly identifies Le Fanu as a proponent of intelligent design theory.  But in his MPS lecture, he was silent about this.

Le Fanu's speech was engaging for many in the MPS audience, but some people became increasingly agitated as he spoke.  Peter Whybrow was particularly irritated.

In the question period, Whybrow assumed a mocking tone in praising Le Fanu for his rhetorical skills in moving his audience, and he said that in the future he would adopt some of Le Fanu's tricks for persuading an audience.  Le Fanu answered: "Thank you for those condescending remarks."

This testy exchange manifested the emotional depth of the debate over whether Darwinian science can fully explain human experience.  This pointed ahead to the final two lectures of the conference on the evolution of religion.

Some of my posts on related topics can be found here, here, here, here., here., and here.

The MPS in the Galapagos (12): The Evolutionary Neurobiology of Entrepreneurial Behavior

Later in the morning of June 27th, Peter Whybrow spoke on "The Entrepreneur: Adaptive Response to Evolving Opportunity."  Whybrow is the Director of the Semel Institute for Neuroscience and Human Behavior at UCLA.

Hayek and the Austrian School Economists emphasize the importance of entrepreneurial risk-taking in responding to uncertain and unpredictable opportunities in ways that central planners cannot do.  The entrepreneur manifests the distinctive human personality of those inclined to take risks in exploiting opportunities in their environment. 

Whybrow's lecture was a good contribution to this MPS conference, because he offered a Darwinian theory of the entrepreneurial personality as an evolved propensity of the human brain.  And yet the weakness in Whybrow's presentation was that he did not acknowledge the serious problems with his genetic explanations of entrepreneurial behavior.

Whybrow began by suggesting that if we define the entrepreneur broadly as someone who engages in "creative risk-taking," then Charles Darwin was an entrepreneur in developing his theory of evolution, and Peter and Rosemary Grant were entrepreneurs in developing their research on "Darwin's finches" in the Galapagos to prove Darwin's theory.

In his account of the Grants' research on the finches, Whybrow repeated the popular view--as conveyed in Jonathan Weiner's The Beak of the Finch--that the Grants have actually observed the evolution of new species on Daphne Major.  But as I have indicated in a previous post, this is not true.  As even Weiner admits, while the Grants have shown that natural selection leads to evolutionary change within a species, they have not shown that this evolutionary change leads to new species.

Whybrow's main argument was that the personality of the entrepreneurial risk-taker was an evolutionary adaptation for responding to evolving opportunities, and that this personality had a genetic basis.  The genetic basis for this is that some forms of the dopamine D4 receptor gene is associated with a propensity to risk-taking, and therefore natural selection could have favored this gene in selecting for risk-taking behavior.

In some ways, Whybrow's argument overlapped with Charles Murray's argument about the biology of human diversity.

Whybrow declared: "DRD4 has a role in modulating cognitive and emotional behavior."  "The DR4-7 repeat is associated with risk taking."  "In a study of 94 young men (Harvard) the DRD4-7 allele was highly correlated with financial risk taking, accounting for some 20% of the variance."

We might state his reasoning in a simple way:  Genes have some influence on personality, and personality has some influence on behavior.  It's hard to dispute this.  But, of course, the problem is figuring out what is meant by "some influence."  What exactly is meant by "associated with" or "correlated with"?  In one case, it's "20% of the variance."  So 80% of the variance is not accounted for?

Particular genes influence but do not specify behavior, because genes interact with other genes, with other biological factors (including epigenetic regulation of genes), with the physical and social environments, and with individual judgments.  So identifying particular genes "associated with" some kind of behavior does not take us very far in explaining that behavior.

Whybrow relied on two kinds of studies in behavior genetics--heritability studies and gene association studies.  Heritability studies use adoption studies and twin studies to determine the proportion of phenotypic variance in a given population that can be attributed to genotypic variance.  Gene association studies look for statistically significant associations between particular genes and particular phenotypic traits.  The problem here is that such studies rely on assumptions that are not true.  For example, twin studies assume that 100% of the genes of monozygotic twins are genetically identical, and that 50% of the genes of dizygotic twins are genetically identical.  We know this is not true, because identical twins are not really genetically identical: transposable elements and copy number variations in DNA create variation between individuals.

The recent research in genetics showing the falsity of the assumptions in behavior genetics has been well surveyed by Evan Charney ("Behavior Genetics and Postgenomics," Behavioral and Brain Sciences 35 [2012]: 331-410).  I have commented on some of these issues in a  previous post.

I agree with Whybrow that evolution can shape genes that have some influence on traits of temperament that have some influence on behavior.  But identifying such genes does not allow us to predict human behavior.  We cannot predict complex human phenotypes--such as entrepreneurial risk-taking--from a human genotype.  The ultimate evolutionary reason for this is that human beings have evolved for phenotypic plasticity--the capacity to change one's phenotype in response to a highly complex and variable physical and social environment.  Human genetics constrains but does not determine human cultures and human judgments.

Evolutionary science gives us no escape from the unpredictable contingency and irreducible complexity of human history.  In fact, evolutionary science itself is a historical science that has little predictive power, in contrast to nonhistorical sciences like physics and chemistry.

This theme of the contingency and complexity of human life and of entrepreneurs as people who gamble in their attempts to find opportunities in such a world was taken up by John Kay, who spoke in the afternoon.

Kay is a prominent British economist who studies the relationships between academic economics and business behavior.  He writes a column for the Financial Times. 

Kay spoke about his studies of casino gambling in London, in which he found that many of the gamblers were successful entrepreneurs.  Remarkably, they play games of pure chance (such as roulette and black jack) as if they know they're going to win.  They are people who exaggerate their control over things.  The traits that make them successful entrepreneurs also make them irrational gamblers. 

The great point of interest for Kay is that this contradicts the standard model of economic behavior as taught by economists.  Modern financial economics rests on three broad claims.  First, as a prescriptive premise, we decide what to do based on a calculation of probabilities and expected utilities in managing risk.  Second, as a descriptive premise, rational calculators are more successful, which assumes a casual evolutionary argument in which maximizing our expected utility equals reproductive fitness.  Finally, equilibrium results from this.

Kay explained that this standard model was based on the dominant view of economists (like Frank Ramsay Savage and Milton Friedman) that risk can be weighed for probability in making a rationally calculated decision.  Against the dominant view, Keynes and Frank Knight had argued that uncertainty in economic life provides no scientific basis for a calculation of probability.  Hayek was on Knight's side in arguing that events cannot be calculated by probability because they are open-ended.

Kay argued that we needed to see the truth in the Knight/Hayek insight into uncertainty.  We need entrepreneurs who act in the face of uncertainty with an irrational optimism that they will win.  On the other hand, we also need calculators who do calculate the probabilities of risks where that is possible.  In casinos, the calculators are the casino owners who calculate probabilities in order to make money at the expense of the entrepreneurs.

Presumably, Whybrow would say that what we see here in the calculators and entrepreneurs are two different kinds of personality that might be evolutionary adaptations for responding to different kinds of opportunities.

Wednesday, July 24, 2013

The MPS in the Galapagos (11): Wrangham on the Evolution of War

The question of whether the original state of nature for human beings was a state of war or a state of peace has been a contentious question in political philosophy, beginning with Hobbes, Locke, and Rousseau.  This continues to be one of the most intensely debated questions in the social sciences, with some people adopting the Hobbesian view of the state of nature as a state of war, and others adopting the Rousseauian view of the state of nature as a state of peace.  Most recently, the debate has been renewed in this week's issue of Science with Douglas Fry's defense of the Rousseauian position and attack on Richard Wrangham's Hobbesian position.  Fry's article has drawn a lot of press coverage, including a feature article in The Economist.

As someone who combines interests in the history of political philosophy and Darwinian anthropology, I see this debate as an illustration of how modern empirical research in evolutionary biology can illuminate old disputes in political philosophy.  As I have indicated in some previous posts, early modern political philosophers (from Hobbes to Smith) studied and debated the anthropological reports about the social life of the native Americans as showing the original condition of humanity.  As Locke declared: "In the beginning, all the world was America." 

This shows that political philosophy is an empirical evolutionary science of politics.  Consequently, the serious study of the history of political philosophy must include the study of evolutionary science.  This should be evident when one considers the philosophic implications of the current anthropological debate over the evolution of war and peace.

I was pleased, therefore, by Wrangham's lecture on "Why Evolution Matters for War" at the MPS conference, which allowed me to think more about this debate and its ramifications for political philosophy.  Much of what Wrangham said in his lecture has been elaborated in a recent article in Human Nature that he coauthored with Luke Glowacki.

Wrangham is a Professor of Biological Anthropology in the Department of Human Evolutionary Biology at Harvard University.  (In 2009, the program of Biological Anthropology in the Department of Anthropology at Harvard was reconstituted as a new Department of Human Evolutionary Biology.)  He is the co-director of the Kibale Chimpanzee Project, which is a long-term study of the Kanyawara chimpanzees in Kibale National Park in Uganda.  His book Demonic Males: Apes and the Origins of Human Violence (1996) is a book that I have found useful as a text in some of my political theory classes. 

Here's a general summary of Wrangham's position as stated in the abstract for his article in Human Nature:
"Chimpanzee and hunter-gatherer intergroup aggression differ in important ways, including humans having the ability to form peaceful relationships and alliances among groups.  This paper nevertheless evaluates the hypothesis that intergroup aggression evolved according to the same functional principles in the two species--selection favoring a tendency to kill members of neighboring groups when killing could be carried out safely.  According to this idea, chimpanzees and humans are equally risk-averse when fighting.  When self-sacrificial war practices are found in humans, therefore, they result from cultural systems of reward, punishment, and coercion rather than evolved adaptations to greater risk-taking.  To test this 'chimpanzee model,' we review intergroup fighting in chimpanzees and nomadic hunter-gatherers living with other nomadic hunter-gatherers as neighbors.  Whether humans have evolved specific psychological adaptations for war is unknown, but current evidence suggest that the chimpanzee model is an appropriate starting point for analyzing the biological and cultural evolution of warfare" (5).
Wrangham contrasts his "chimpanzee model" with "human-specific models" and "nonadaptive models" for explaining the evolutionary basis of war.  The "human-specific models" agree with the "chimpanzee model" in seeing war as an evolutionary adaptation, but they see uniquely human psychological propensities to war that are not shared with chimpanzees--such as propensities for taking self-sacrificing risks in war (proposed by Samuel Bowles as "parochial altruism"), tendencies for "strong reciprocity" (Herbert Gintis), or revenge-seeking (Christopher Boehm).

The "nonadaptive models" deny that there has been any evolutionary selection for warfare among prehistoric hunter-gatherers, and consequently warfare has been a purely cultural development of agrarian societies with centralized states and military bureaucracies.  The reasoning for this kind of model is evident in some excerpts from Douglas Fry's article, coauthored with Patrik Soderberg, in Science: 
"It has been argued that warfare evolved as a component of early human behavior within foraging band societies.  We investigated lethal aggression in a sample of 21 mobile forager band societies (MFBS) derived systematically from the standard cross-cultural sample.  We hypothesized on the basis of mobile forager ethnography, that most lethal events would stem from personal disputes rather than coalitionary aggression against other groups (war).  More than half of the lethal aggression events were perpetrated by lone individuals, and almost two-thirds resulted from accidents, interfamilial disputes, within-group executions, or interpersonal motives such as competition over a particular woman.  Overall, the findings suggest that most incidents of lethal aggression among MFBS may be classified as homicides, a few others as feuds, and a minority as war" (270).
"The findings suggest that MFBS are not particularly warlike if the actual circumstances of lethal aggression are examined.  Fifty-five percent of the lethal events involved a sole perpetrator killing only one individual (64% if the atypical Tiwi are removed).  One-person-killing-one-person reflects homicide or manslaughter, not coalitional killings or war.  Additionally, 36% of all lethal events occurred within the same local group (62% if the atypical Tiwi are removed), and violence within a local group is not coalitional war.  Only 15% of the lethal events occurred across societal lines. . . ."
"Approximately half of the societies had no lethal events that involved more than one perpetrator.  This observation is incongruent with assertions by Bowles and Pinker that war is prevalent in MFBS or by Wrangham and Glowaki that humans have an evolved tendency to form coalitions to kill members of neighboring groups. . . ."
"In conclusion, when all cases are examined for a systematically drawn sample of MFBS, most incidents of lethal aggression can aptly be called homicides, a few others feud, and only a minority warfare.  The findings do not lend support to the coalitionary model.  The predictions are substantiated that MFBS, as a social type, possess many features that make warfare unlikely. . . ." (272) 
In response to this kind of argument, Wrangham has identified five weaknesses in Fry's reasoning that are commonly found in "nonadaptive models."

First, Fry fails to distinguish "simple warfare" and "complex warfare," and then he assumes that hunting-gathering societies show no warfare if they don't show complex forms of warfare.  "Simple" warfare is found in small societies without formal political hierarchies, and it consists mostly in raiding and feuding without lethal battles between organized opponents.  "Complex" warfare is found in larger societies with formal political hierarchies where lethal battles are fought by soldiers under the command of leaders.  Chimpanzees and some other animals show "simple" but not "complex" warfare.  When Fry finds little evidence of "complex" warfare among hunter-gatherer societies, he falsely concludes that there is no warfare at all.  So he sees a record of raiding and feuding among hunter-gatherers but refuses to recognize this as war.

The second weakness is that Fry does not distinguish between "internal" and "external" war.  "Internal" war is war among the bands belonging to the same society--the same cultural or linguistic group.  "External" war is war between people of different societies--different cultural or linguistic groups.  Wrangham has argued that while there is no stable pattern to "internal" warfare, there is a stable pattern of hostility in "external" war.  Fry's conclusion that coalitionary killing is not a uniform tendency in internal warfare has no relevance to Wrangham's claim that coalitionary killing is an evolved human tendency in external warfare.

The third weakness is that Fry fails to identify the crucial criteria for determining whether a hunter-gatherer society provides the best model of prehistoric behavior.  A crucial criterion for Wrangham is whether a hunting-gathering society was constrained by neighboring farming societies.  By the time most of these recent hunting-gathering societies were studied, they were bordered by farming societies that could dominate them politically and militarily, and so if the hunter-gatherers had no record of warfare, this could easily be explained as coming from a wise calculation that war was futile.  If one is looking for situations comparable to those faced by our original hunter-gatherer ancestors, one would need to look only at hunter-gatherer societies with neighboring societies of hunter-gatherers.  The anthropological record shows only a few cases like this, including societies in Alaska, Tasmania, Australia, the Andaman Islands, New Guinea, and Tierra del Fuego.  When Wrangham and Glowacki surveyed the record for these societies, they found a universal pattern of warfare.

The fourth weakness in Fry's reasoning is his assumption that proof of hunter-gatherer warfare would require that a high proportion of violent deaths should come from war.  But that does not follow if one agrees with Thomas Hobbes: "For Warre, consisteth not in Battel only, or in the act of fighting, but in a tract of time, wherein the will to contend by Battel is sufficiently known."  Even when hunter-gatherer societies have long periods without high death rates from war, there can still be a perpetual state of hostility and readiness to go to war.

The final weakness in Fry's position is his assumption that affirming the evolutionary roots of war is affirming that war is inevitable and ineradicable, and therefore those (like himself) who deny the evolutionary roots of war are thereby promoting peace.  This is not true, because explaining the evolutionary propensity to war in human nature is not to affirm this as a necessity that cannot be changed.  In fact, understanding war as a natural propensity can be a precondition for understanding how best to promote peace.  That's evident, for example, in Steven Pinker's The Better Angels of Our Nature.  Pinker agrees with Wrangham and others who argue for primitive warfare as an evolutionary adaptation.  But for Pinker (as well as Wrangham), this helps us to understand the conditions required for promoting the modern decline in violence.  We must see how the "inner demons" of our human nature can be overcome through the "better angels" of our nature.

The strange assumption that Fry's position somehow occupies the moral high ground in this debate is manifest in the article by Elizabeth Culotta in the "News & Analysis" section of Science highlighting Fry's article.  She says that Fry's article "strikes a blow for peace," as if Fry's critics were motivated by a love of war, which is clearly a false claim.

It would be instructive if Fry would write a response to Wrangham's criticisms.

If Wrangham is right in his critique of Fry's reasoning, then this would suggest that the evidence now supports the conclusion that Hobbes was right, and Rousseau was wrong.


"The Origins of War," The Economist,  July 20, 2013, pp. 69-70.

Culotta, Elizabeth, "Latest Skirmish Over Ancestral Violence Strikes Blow for Peace," Science, 341 (19 July 2013): 224.

Fry, Douglas P., and Patrik Soderberg, "Lethal Aggression in Mobile Forager Bands and Implications for the Origins of War," Science, 341 (19 July 2013): 270-73.

Wrangham, Richard W., and Luke Glowacki, "Intergroup Aggression in Chimpanzees and War in Nomadic Hunter-Gatherers: Evaluating the Chimpanzee Model," Human Nature, 23 (2012): 5-29.

Science News has an article on the Wrangham-Fry debate that can be found online.

Some other posts on the evolution of war and peace can be found here, here,  here., here., here, and here.

The MPS in the Galapagos (10): Deepak Lal on the Pax Americana

On June 26, there was a break in the conference so that participants could tour the island of San Cristobal.  The conference resumed the morning of the 27th with lectures on war by Deepak Lal and Richard Wrangham.

Professor Lal is a former President of the Mont Pelerin Society and a Professor of International Development Studies at UCLA.  He is the author of many books on international economic development and globalization, including In Praise of Empires (2004).

Lecturing on "War and Peace," Lal argued that empires can maintain global order and thus maintain peace.  They do this by securing life against violence and by enforcing promises and rules of property.  The British Empire did this in the nineteenth century, and the American Empire has done this since the end of World War II.

Lal presented this argument as a refutation of Steven Pinker's argument about the history of declining violence in his Better Angels of Our Nature.  Pinker is wrong, Lal claimed, about the "Long Peace" since 1945 and the "New Peace" since 1989, because he does not recognize that this peace (the absence of war between the Great Powers) has been enforced by the global imperial power of the United States, just as the British Empire had done in the previous century.  The bloody warfare of the first half of the twentieth century shows the consequences of the British withdrawal from its imperial role.  Lal illustrated his argument (p. 4) with Pinker's Figure 5-12 (on p. 224 of Better Angels), which shows the "percentage of years in which the great powers fought one another, 1500-2000."  Lal pointed out that this pattern could be interpreted as showing that peace between the great powers coincides with an imperial Pax.

Although Lal seemed to think he had totally refuted Pinker's argument, I was not persuaded.  Except for the one reference to Figure 5-12, Lal did not refer to any passages in Pinker's book.  Lal said nothing about Pinker's larger argument about declining violence as more than just declining war--including declines in homicide generally, capital punishment, legal torture, moralistic violence, spousal abuse, rape, and so on.  I don't see how Lal's imperial Pax explains all of this.

Lal made a good case for the conclusion that Pinker should have added the imperial Pax as one factor explaining declining violence, but this would only be a modification of Pinker's general argument.

Moreover, it seems that Lal actually accepts most of Pinker's arguments.  He certainly accepts Pinker's argument for the importance of the "Hobbesian pacification."  Indeed, Lal's imperial Pax could be understood as an extension of the Hobbesian pacification to the international arena.

Consider the following from Lal's paper:
"True, these ancient empires did not seek to end various barbarous violent practices which were very much part of their cosmological beliefs, as I have characterized them in my Olin lectures, Unintended Consequences, and Pinker is right in the importance of what he calls the Civilizing and Humanitarian Processes, whose evolution I also traced in my book.  But nevertheless, given these common failures to tame the instincts of the wolf in all civilizations till recently, the role of empires in maintaining peace and prosperity in their domains cannot be gainsaid" (3).
If Lal concedes that Pinker is right about the Hobbesian Pacification, the Civilizing Process, and the Humanitarian Revolution, then Lal is going a long way towards conceding Pinker's major arguments.

Moreover, Lal was silent about the evidence cited by Pinker (283-84) for the Democratic Peace theory: "The Democratic Peace held not only over the entire 115 years [1886-2001] spanned by the dataset but also in the subspans from 1900 to 1939 and from 1989 to 2001.  That shows that the Democratic Peace is not a by-product of a Pax Americana during the Civil War.  In fact, there were never any signs of a Pax Americana or a Pax Britannica: the years when one of these countries was the world's dominant military power were no more peaceful than the years in which it was just one power among many."  Here Pinker is citing Bruce Russett and John Oneal, Triangulating Peace: Demcracy, Interdependence, and International Organizations (Norton, 2001), 188-89: "Great hegemonic power does not dampen conflict in the system during these more normal periods of international relations, when there are no big wars among the major powers.  Rather, the level of dyadic conflict rises.  There is no evidence in these results of a Pax Britannica or Pax Americana, contrary to both hegemonic stability and power transition theories."

Monday, July 22, 2013

The MPS in the Galapagos (9): Matt Ridley on Adam Darwin

Originally, Matt Ridley was scheduled to be one of the speakers at the MPS conference in the Galapagos.  When I heard that he had cancelled his trip to the conference, I was disappointed.  But then I learned that there was a good reason for his cancellation:  as Viscount Ridley, he was elected to the British House of Lords in February as a Conservative hereditary Peer, and his new Parliamentary duties forced a change in his schedule.  He delivered his maiden speech to the House of Lords on May 14th.

If he had spoken at the conference, he probably would have delivered a modified version of the lecture he gave at the Adam Smith Institute in London on November 13th of last year--"Adam Darwin: Emergent Order in Biology and Economics."  A video of the lecture is available online.

Having just watched the video and having read a transcript of the lecture, I feel both frustration and relief.  I am frustrated by the thought that the similar themes in our lectures would have promoted a good discussion.  But I am also relieved that my lecture was not overshadowed by the brilliance of Ridley's presentation.

In my lecture, I argued that the publication of Darwin's Origin of Species in 1859 made it possible, for the first time in history, to be an intellectually fulfilled liberal, because Darwinian evolutionary science has shown that Adam Smith was right about almost everything.  In his defense of what he called "the natural system of liberty," Smith was right to see that the social orders of morals, markets, and laws can arise as largely spontaneous orders, which emerge as unintended outcomes from the actions of individuals pursuing the satisfaction of their individual desires.  The Darwinian science of evolutionary order has confirmed this central idea of Smithian liberalism.

Ridley expresses better than I can the deeper implications of this idea.  Here are a few of my favorite excerpts from his lecture.

"I have called my lecture 'Adam Darwin' to stress how congruent the philosophies of Adam Smith and Charles Darwin are.  The common theme is emergence: the idea that order and complexity can be bottom-up phenomena that need no designer.  Both economies and ecosystems emerge."

"But my purpose is to explore not just the history and evolution of this shared idea, but its future, to show that in the age of the internet Adam Darwinism is the key to understanding how the world will change."

After surveying the history of Smith's influence on Darwin's thinking, Ridley observes:

"Today, generally, Adam Smith is claimed by the Right, Darwin by the Left.  In the American red states, where Smith's emergent, decentralized philosophy is all the rage, Darwin is often reviled for his contradiction of dirigiste creation.  In the average British university, by contrast, you will find fervent believers in the emergent, decentralized properties of genomes and ecosystems who demand dirigiste policy to bring order to the economy and society.  Yet if the market needs no central planner, why should life need an intelligent designer--or vice versa? . . ."

". . . innovation is an evolutionary process.  That's not just a metaphor; it is a precise description. . . . innovation happens mainly by trial and error. . . ."

". . . In other words, intelligent design is just as bad at explaining innovation as it is explaining evolution.  Discovery comes from pluralism and serendipity, not command and control."

"Notice that the cultural evolution I am describing is the very opposite of social Darwinism, the notion that we should order society so as to encourage biological evolution.  Because bad ideas die in competition with good ones, people do not have to die.  The more we allow our technologies and institutions to evolve, the more we can afford to keep the poor, the disabled, and the weak alive.  This crucial point is often missed by my critics, especially the philosopher John Gray, who reviewed my book for the New Statesman and made this elementary howler, accusing me of social Darwinism.  Cultural evolution makes social Darwinism less likely, not more.  A country of grinding poverty and frequent warfare--fifteenth century England or twenty-first century Congo--is far more social Darwinist than a rich consumer society."

"Sex is what makes evolution a cumulative force--what makes it creative rather than conservative.  Without the swapping of genes between individuals, you cannot get good mutations except through inheritance. . . ."

"Evolution really got going when it invented sex.  So what's the equivalent of sex in culture and technology?  The answer is obvious to a student of Adam Smith: exchange.  Adam Smith more than anyone else spotted that exchange is a uniquely human characteristic.  'No man ever saw a dog make fair and deliberate exchange of a bone with another dog,' he wrote.  And he was right.  I have been going around the world trying to persuade biologists that only human beings indulge in exchange of objects and services between strangers. . . ."

". . . Only human beings routinely exchange things between strangers.  Only in human beings does culture have sex.  Only in human beings is culture cumulative and progressive.  Exchange was the key invention that led to the explosion of technology and economic progress in our species: not language, or tools, or self awareness or big brains.  We had all those for hundreds of thousands of years and remained rare and simple hunter-gatherers.  It was when we invented exchange that the human revolution happened."

"Adam Smith, in other words, has the answer to an evolutionary puzzle: what caused the sudden emergence of behaviourally modern human beings in Africa in the past hundred thousand years?  In that surprisingly anthropological first chapter of The Wealth of Nations, Smith saw so clearly that what was special about human beings was that they exchanged and specialized."

". . . Just as sex gives a species access to innovation anywhere in its species, so exchange gives you access to innovation anywhere in your species."

". . . I am constantly being told that to believe in markets is to believe in selfishness and greed.  Yet I think the very opposite is true.  The more people are immersed in markets, the more they collaborate, the more they share, the more they work for each other.  In a fascinating series of experiments, Joe Henrich and colleagues showed that people play ultimatum games more selfishly in more isolated and self-sufficient hunter-gatherer societies and less so in more market-integrated societies."

"History shows that market-oriented, bottom-up societies are kinder, gentler, less likely to go to war, more likely to look after the poor, more likely to patronize the arts, more likely to look after the environment than societies run by the state.  Hong Kong versus Mao's China. Sixteenth century Holland versus Louis XIV's France. Twentieth century America versus Stalin's Russia.  The ancient Greeks versus the ancient Egyptians.  The Italian city-states versus the Italian papal states.  South Korea versus North Korea.  Even today's America versus today's France.  And so on.  Example after example of what Montesquieu called Le Doux Commerce."

"The entire drift of human history has been to make us less self-sufficient, more dependent on others to provide what we consume and on others to consume what we provide.  That's the very source of prosperity and innovation.  It's time to reclaim the word collectivism from the statists on the left.  The whole point of the market is that it does indeed collectivize society, but from the bottom up not the top down.  We surely know by now, after endless experiments that a powerful state encourages selfishness: that's the very point of public choice theory."

"In terms of human prosperity, we ain't seen nothing yet.  And because prosperity is an emergent property, an inevitable side-effect of human exchange, we could not stop it even if we wanted to.  All we could do is divert it elsewhere on the planet--which we in England seem intent on doing, by the way."

"Adam Darwin did not invent emergence.  His was an idea that emerged when it was ripe.  And like so many good ideas, it was already being applied long before it was even understood."

"So I give you Adam Darwinism as the key to the future."

Some parts of this lecture were previously published in The Spectator in 2009 in Ridley's article "The Natural Order of Things."

If Ridley had spoken at the MPS conference, I would have raised two points of disagreement with him.  First, if he's saying that American conservatives who support both free markets and intelligent design theory or creationism are being inconsistent, then I disagree.  There is no logical contradiction in saying that while economic order is largely a spontaneous or unintended order, biological order is not.  Whether spontaneous order explains both depends on how similar we believe them to be.

Moreover, the intelligent design theorist or creationist might argue that just as a spontaneous economic order depends on the right initial conditions being enforced by government, so does biological order depend on the initial conditions set by God at the beginning.  This might be unreasonable, but it is not inconsistent.

This leads to my second point of disagreement with Ridley, which is elaborated in my MPS paper.  His version of evolutionary liberalism shows an almost anarchistic scorn for government, which is contrary to what Smith says.  Liberalism assumes that society is a largely, but not completely, self-regulating unintended order, in that some limited governmental regulation is required to enforce legal rules of property and exchange, to prohibit force and fraud, to secure the military defense of society, and to provide certain public goods.  Smith rightly defended such a limited government as necessary for the "natural system of liberty."

Sunday, July 21, 2013

The MPS in the Galapagos (8): The Evolution of Morality

The afternoon of June 25th at the MPS conference was devoted to lectures on the evolution of morality by David Rose, John Tooby, and Gerald Gaus.  Since I have already commented on the paper by Cosmides and Tooby, here I will only comment on Rose and Gaus.

Rose spoke on "Evolving Around the Empathy Problem".  He is an economist at the University of Missouri at St. Louis.  His lecture seemed to be based on an argument that he has elaborated in a book--The Moral Foundation of Economic Behavior (Oxford University Press, 2011).  Since I have not read that book, I am not confident about my interpretation and assessment of his lecture.  The questions I have about the lecture might be answered in the book.

Rose agrees that empathy is important for morality, but he thinks empathy is not enough, particularly in providing a moral foundation for modern market economies.  Empathy is not enough because it works better in small groups than it does in the large groups that constitute modern societies.  In large groups, the harm caused by an opportunistic act can be spread out over so many people that no one individual suffers any great harm, and thus there is no specific individual suffering to evoke empathy and elicit guilt in the mind of the person acting opportunistically.

So, for example, Rose explained, old people can use their political influence to take resources from their children and grandchildren through deficit spending.  The old people love their children and grandchildren, but the harm to their offspring from deficit spending is spread out in such a way that the old people don't feel guilty about it because they don't imagine the individual harm being very great.

This is Rose's version of the Cosmides/Tooby/Dunbar theory of "mismatch"--our moral psychology as evolved for life in small groups does not provide the moral restraint that we need in the large groups of modern society.

Rose's answer to this problem is to argue that our genetic nature had to be overcome through cultural evolution that would provide the moral restraint necessary for the economic life of a modern society.  We needed parents to teach their children what Rose calls "principled moral restraint," which is the idea that some actions are inherently wrong, and thus not to be done, regardless of the effects on others.  So if something is wrong--like stealing from your children--it is wrong, and you should feel guilty for it, even when you can't see any clear harm for specific individuals.

Rose's argument, then, is that the success of modern free market activity in creating a growth in prosperity that is unprecedented in human history occurred because parents in some societies started to teach their children principled moral restraint.  These societies prospered because economic transactions could be based on the trustworthy behavior of people who would feel guilty for opportunistic behavior even when there were no circumstance to elicit empathy.  Other societies without such a culture of principled moral restraint would be less prosperous, and thus they would be less successful in cultural evolution.  Rose suggests that something like this is similar to Hayek's theory of cultural evolution as supporting the emergence of modern free societies.

My first reaction is that this is philosophically and historically implausible.  It's philosophically implausible because it assumes a Kantian conception of duty for duty's sake with no regard for consequences or moral emotions that seems implausible.

It's historically implausible, because it's hard to see how Rose could prove that the Industrial Revolution occurred when parents decided to teach Kantian morality to their children, and ever since then, the only prosperous societies have been those where the parents taught this to their children.  Where's the evidence for this?

Moreover, since the rate of growth in prosperity has been increasing around the world for the past two centuries, Rose would have to show that this is because more parents are teaching Kantian morality to their children.  But it that's so, how does he explain his example of old people in the developed world who are harming their children through deficit spending?  Does that mean that parents have stopped teaching Kantian morality to their children?

Again, however, I fear that I might be missing answers that Rose has provided in his book.

Jerry Gaus spoke about "The Evolution, Evaluation, and Reform of Social Morality: A Hayekian Analysis".  Gaus is a Professor of Philosophy at the University of Arizona.

He began his lecture by warning that, like many contemporary philosophers, he would be speaking at a very abstract level of conceptual analysis that many in the audience might find difficult to handle at the end of a long day.  He then demonstrated that his warning was justified.

Nevertheless, despite the difficult abstractness of his speech, he did point to some fundamental questions for any evolutionary study of morality.  For most of his fellow philosophers, he argued, the question is: How is the evolution of morality related to morality?

Gauss explained that rather than being concerned with what people think morality is--perhaps as a result of human evolutionary history--most moral philosophers are concerned with what morality really is.  For these philosophers, this separates science from philosophy.  Evolutionary scientists might explain to us how the common human understanding of morality has developed.  But this science of the origins of moral beliefs and practices tells us nothing about what is really right or wrong: it tells us about the empirical world of moral life but not about the normative world of what truly is right or wrong.  Determining the normativity of the intrinsically right or wrong is the job of normative moral philosophy.

This is an important observation, because it explains why so many moral philosophers have rejected any evolutionary science of morality as irrelevant to the philosophic study of normative standards.  It also explains why some moral philosophers have concluded that if evolutionary science really can explain morality completely as nothing more than an evolutionary adaptation, this would be nihilism.  Another way of putting this point, as I have in some previous posts, is that most moral philosophers today are Platonists in assuming that if morality has any objective reality, it must be rooted in cosmic standards--a cosmic God, cosmic Reason, or cosmic Nature.  Some of these philosophers are disappointed Platonists--who wish for a Platonic Idea of the Good that they decide doesn't exist--who conclude that morality must be an illusion, perhaps an illusion foisted on us by our evolutionary nature.

Gaus rejected this orthodox view of the moral philosophers, and I agree with him.  We can rightly understand morality as a product not of moral cosmology but of moral anthropology--as rooted in human nature, human culture, and human judgment.  As Gaus indicated, this is a tradition of moral philosophy as an empirical science that stretches from David Hume and Adam Smith to Ken Binmore and Philip Kitcher.

Gaus then developed his own version of this position through an explication of Hayek on moral order as an evolutionary order, in which we start with existing rules and make them more coherent.

As an abstract argument, Gaus's lecture was persuasive to me.  But I would like to have seen some illustrative studies of moral history.  In his paper, there is one sentence about the debate over homosexuality and homosexual parenting (18); and there are a few sentences on J. S. Mill's analysis of capitalism and socialism (28).  Beyond those few sentences, he never takes up any concrete cases of moral debate in human history.  But if morality really is a product of human history, as he argues it is, then he would have to take up that moral history stretching back to our earliest human ancestors.

Saturday, July 20, 2013

The MPS in the Galapagos (7): Evolutionary Liberalism and the "Mismatch" Theory

Leda Cosmides and John Tooby spoke in the morning and afternoon of June 25th about the evolutionary psychology of cooperation, economics, and morality.  As their paper for the conference, they submitted a paper on "Evolutionary Psychology, Moral Heuristics, and the Law".  This was originally published in Gerd Gigerenzer and Christoph Engel, eds., Heuristics and the Law (Cambridge: MIT Press, 2006), pp. 176-206.

Cosmides is a Professor of Psychology at the University of California at Santa Barbara, where Tooby is a Professor of Anthropology, and where both direct the Center for Evolutionary Psychology.  Their successful promotion of evolutionary psychology as an academic field of study is a remarkable story.  When they first began their work in the 1980s and early 1990s, their arguments provoked intense resistance among academic scholars.  But now evolutionary psychology has become a prominent field in many academic departments--particularly, psychology, anthropology, and economics.  In recent years, it has begun to show itself in some departments of political science and English.

Coming after my lecture earlier in the morning on Darwinian liberalism, their remarks and their paper helped me to think about whether they agree with me that classical liberalism can be defended as rooted in our evolved human nature.  The answer seems to be yes and no.

Yes, they agree with me that liberal societies--open societies with free markets and limited governments--have proven to be the most productive societies in human history, because they secure the social and economic benefits of voluntary association and exchange.  Yes, they agree with me that collectivist societies with central planning enforced by governmental coercion have failed, because they are contrary to our evolved human nature.  (Tooby remarked that he had been reading Friedrich Hayek for over 40 years and that his thinking has been much influenced by Hayek.)

But from another point of view, Cosmides and Tooby disagree with me, because they think that the evolved psychology of our hunting-gathering minds supports the moral instincts for communal sharing that make collectivist central planning appear to us to be morally superior to the spontaneous order of market exchange.

Here we see their "mismatch" theory--the idea that our evolved hunting-gathering psychology is adaptive for the ancestral societies of small foraging groups, but maladaptive for modern societies with millions of individuals who are strangers to one another.  This is similar to Hayek's "atavism" theory--the idea that the natural longing to return to the small communities of our ancient foraging ancestors makes socialist collectivism morally attractive to us despite the fact that it must always fail.  This is what I have called Hayek's Freudianism--the thought that modern liberalism requires a complete suppression of our natural instincts as the condition for enjoying the benefits of a modern free society.

This is an incoherent argument for liberalism.  If a liberal society is so painful, because it requires the suppression of our deepest natural instincts, why does it succeed?  And if a collectivist society satisfies our deepest natural instincts, why does it fail?

This incoherence is evident in the paper that Cosmides and Tooby submitted for the conference.

They say that "the mismatch between the ancestral world and current conditions is so great that laws that seem virtuous to our hunter-gatherer minds often have unanticipated social consequences that are disastrous, and laws that seem morally dubious can be engines of social welfare" (181).  So "our hunter-gatherer minds" deceive us.  But Cosmides and Tooby can use their "hunter-gatherer minds" to see how they are deceived by their own minds, and they assume that they can appeal to our "hunter-gatherer minds" to see the deception coming from our minds.  So it seems that the "mismatch" in our minds is not so deep that we can't use our minds to see it and then correct it.  In understanding how the mind actually works, which is what Cosmides and Tooby want to do, we must understand how that mind has evolved to correct itself and thus overcome the "mismatch."

What exactly is the "mismatch"?  They write:
"Karl Marx thought that extant hunter-gatherers (and by extension, our ancestors) lived in a state of primitive communism, where all labor was accomplished through collective action and sharing was governed by a decision rule, 'from each according to his ability to each according to his need.'  He thought the overthrow of capitalism would bring forth an economically advanced society with similar properties: abolish private property and all labor will once again be accomplished through collective action and, because the mind reflects the material conditions of existence, the hunter-gatherer communal sharing rule will emerge once again and dominate social life" (188)
But then Cosmides and Tooby indicate that the communist regimes that tried to put Marx's vision into practice failed.  So the "mismatch" here might be that the "communal sharing rule" that worked for the "primitive communism" of hunter-gatherers living in small groups does not work in a large-scale modern society. 

In speaking about ants, Edward Wilson once observed: "socialism really works under some circumstances.  Karl Marx just had the wrong species" (Bert Holldobler and Wilson, Journey to the Ants, 1994, 9).  Would Cosmides and Tooby say that Wilson is wrong, because socialism really works for human hunter-gatherers, and thus has worked well for most of human evolutionary history?  This would assume that Marx was right about hunter-gatherers being communists. 

But then Cosmides and Tooby cast doubt on that assumption.  Among hunter-gatherers, they observe, meat is often shared communally, because success in hunting is to a large extent due to luck rather than effort, and thus it is beneficial for individuals to have the meat communally shared as insurance against bad luck in their individual hunting.  But the rules are different for other kinds of resources.  Cosmides and Tooby explain:
"Meat notwithstanding, hunter-gatherer life is not an orgy of indiscriminate sharing, nor is all labor accomplished through collective action.  Aside from meat, very little is shared at the band-wide level.  Plant foods are usually gathered by individuals, who share them primarily with other members of their nuclear family . . . . When sharing outside the family occurs, the neediest in the community are not the first or most likely targets (although need plays a role).  Conditional sharing--reciprocation--is common.  Within a community, each family partners with a small number of other families, and resource sharing is characterized by informal, implicit reciprocation with delay. . . . When an individual fails to reciprocate (or reciprocates with too little), this is a source of anger, discussion, and enormous tension . . . . Access to foraging territories is governed by explicit, formal reciprocation, as are gift exchanges with specific individuals in distant bands who are cultivated as allies for future times of need . . . . Reciprocation in the form of explicit, simultaneous trade also occurs, often as economic interactions with individuals in neighboring bands . . . ." (189)

This doesn't look like Marx's primitive communism.  In fact, evolutionary studies have shown that Marx was wrong about hunter-gatherer society, because these studies have shown "that selection would not favor indiscriminate sharing, nor would it favor a one-situation-fits-all decision rule for sharing."  And "decision rules producing reluctance to share should be triggered . . . by the perception that a potential recipient's bad outcome resulted from his or her lack of effort" (190).

The description of hunter-gatherer society by Cosmides and Tooby sounds a lot like the descriptions of the earliest human societies by liberal political theorists like John Locke and Adam Smith, who studied accounts of hunter-gatherer societies in the New World and elsewhere.  Locke and Smith thought that the first human beings were biologically predisposed to social cooperation based on kinship and reciprocity, which would include sharing with family members and others who would reciprocate the sharing.  But they did not see indiscriminate sharing, because they believed that private property was natural--first, owning oneself and then extending oneself into resources acquired by one's effort.  Moreover, they saw trading behavior in hunter-gatherers that provided the natural basis for the modern commercial society.  Exchange and the division of labor arises from what Smith called the "a certain propensity in human nature . . . to truck, barter, and exchange one thing for another."  Smith indicated that the emergence of the division of labor through exchange appears originally among hunter-gatherers, where someone might specialize in making bows and arrows that he can trade for some meat captured by a hunter, so that each fills a particular occupation, and thus their joint labor becomes more productive than would be the case if each ere working only for himself.  In The Descent of Man, Darwin argued for a similar pattern of exchange and specialization among hunter-gatherers. 

More recently, Haim Ofek and Matt Ridley have surveyed the evidence that the whole of evolutionary human history for the past 200,000 years can be understood as the progressive extension of human cooperation through exchange and the division of labor--from foraging bands to agrarian states to modern commercial societies in global networks of trade.

A psychological propensity for trade that evolved in small ancestral groups can be extended to ever larger groups.  Cosmides and Tooby recognize this:
"Recursively, formalized dyadic exchange interactions can network individuals into n-person units (partnerships, corporations, non-profit organizations, etc.) that can then be substituted back into dyadic interactions as one of the two parties (Tooby et al. 2006).  Rich complexities internal to the organization need not be understood or represented by external parties who interact with it; they can cognitively reduce it to a single agent on the other side of a two-party exchange.  That is, voluntary exchange directly scales up to include increasing numbers of interactants, so long as it is structured at each interaction as a system in which each party can choose without coercion the best alternative it is offered by any other party.  Each dyadic interaction pumps up average welfare among the interactants" (205).
From this, Cosmides and Tooby conclude that Adam Smith was right that "freely conducted trade does systematically promote general social welfare" (203), and thus a free society with free markets is better than a centrally planned society with governmental command and control.
"In short, voluntary exchange systematically propels net aggregated social welfare upwards in a hill-climbing process to the extent that the opportunity to engage in it is distributed through the population.  The system is driven by consent-driven feedback to sort for ever-increasing benefit-benefit interactions among sets of individuals, so that modern market interactions far transcend what any boundedly rational entity (such as government) could have planned or discovered.  In contrast, the process of decree even by elected representatives has no such richly sensitive feedback element to tailor law to individual circumstances" (205-206).
This would all seem to agree with my argument in my MPS lecture that Darwinian evolutionary science shows that Adam Smith was right about almost everything.  But then Cosmides and Tooby pull back from this conclusion in their insistence that Smithian liberalism is "mismatched" with evolved human nature.

It is not always clear that they really believe this, because so much of what they say contradicts it.  For example, when they explain why the Marxist attempts to collectivize agriculture failed in the Soviet Union and China--because such collectivized labor was contrary to human nature--they indicate that an attempt to collectivize the cultivation of sugar cane in a primitive small-scale society (the Shuar in the Ecuadorian Amazon) failed for the same reasons (201).

In listing the many examples of collectivist societies that failed, Cosmides and Tooby include "intentional communities like New Harmony in the U.S." (206).  Wasn't this a small group of a few hundred individuals?  If the instinctive longing for communal sharing originated as an evolutionary adaptation for life in small groups, why does it fail in small groups like New Harmony, the Israeli kibbutzim, and so on? 

If there is any "mismatch" in human evolutionary history, it would seem to be the contradiction between human nature and collectivism.

To be sure, human beings do have natural desires that can only be satisfied in small groups.  And that's why liberal social orders allow for the pluralist multiplicity of civil society, in which human beings live out their daily lives in families, neighborhoods, churches, schools, charitable organizations, business enterprises, and all the other natural and voluntary associations of a free society.

Finally, let us not forget that hunter-gatherer societies are stateless societies, having no formal governmental coercion by a state.  So if we evolved to live in such societies, then there must be a mismatch between our evolved human nature and statist collectivism.

Previously, I have expressed my doubts about evolutionary "mismatch" in my post on Robin Dunbar's lecture.

Other posts on this issue can be found here, here., here., and here.

Friday, July 19, 2013

The MPS in the Galapagos (6): Darwinian Liberalism

On the morning of June 25th at the MPS conference, I was the opening lecturer, followed by Kenneth Minogue, and then a general discussion.

I lectured on "The Evolution of Darwinian Liberalism."  Since my paper is available online, and since I have written an earlier post on this paper, there is no need to summarize it here.

In my oral presentation of the paper, I addressed four (somewhat overlapping) groups of people in the audience--the classical liberals or libertarians, the Kirkians, the Hayekians, and the evolutionary psychologists.

Given the character of the Mont Pelerin Society, I would assume that almost all the members would consider themselves classical liberals or libertarians in some form.  To them, my appeal was to consider how a Darwinian science of human nature could confirm classical liberal thought, particularly as expressed by Adam Smith.  As I have indicated, someone like Charles Murray would seem to agree with me about this.

Although Russell Kirk was never a member of the MPS, many of its members have been identified with the sort of conservative thinking that he promoted.  At the 1957 meeting of the MPS, Hayek gave his famous speech entitled "Why I am not a Conservative," in which he identified himself as a classical liberal rather than as a conservative.  This was thought to be an expression of his disagreement with Kirk's conservatism, although he did not expressly mention Kirk in the speech.  Kirk was present at the meeting, and he reportedly gave an impromptu response.

My argument is that in many respects, Kirk and Hayek were not far apart.  After all, as many people have noted, they both identified themselves as belonging to the intellectual tradition of Edmund Burke.  Moreover, Kirk was a very liberal conservative, in that he clearly did not espouse the kind of theocratic conservatism represented by someone like Joseph de Maistre, and he feared as much as Hayek did the drift towards socialism and statism.

And yet there was one clear point of disagreement between Hayek and Kirk.  As Hayek indicated in his 1957 speech, the Kirkian conservatives rejected Darwinian evolution as a threat to traditional social order, and Hayek saw this as foolishly mistaken.  Furthermore, Hayek thought the case for liberalism was strengthened by a Darwinian understanding of how a free society can arise by spontaneous evolution.

In contrast to Hayek's evolutionary liberalism, Kirk defended a metaphysical and religious version of conservatism.  The first canon of conservative thought, he declared in The Conservative Mind, was "belief that a divine intent rules society as well as conscience, forging an eternal chain of right and duty which links great and obscure, living and dead."  Consequently, "politics is the art of apprehending and applying the Justice which is above nature."  In later formulations of this first canon, Kirk spoke of the conservative belief in "a transcendent moral order."  In all of his formulations, he connected this principle to "Burke's description of the state as a divinely ordained moral essence, a spiritual union of the dead, the living, and those yet unborn," and he spoke of Burke's view of history as "the unfolding of Design."  He mentioned various schools of thought opposed to this conservative thinking, including "those scientific doctrines, Darwinism chief among them, which have done so much to undermine the first principles of a conservative order."

Here in Kirk we see the common fear of many conservatives that Darwinian science denies a conservative order by denying the religious belief in a transcendental order of moral law.  I have tried to allay this fear by arguing that a Darwinian liberalism can recognize the importance of religious belief for moral life as cultivated in the natural and voluntary associations of civil society.  But a Darwinian liberalism will also recognize that the evolved moral sense of human beings can stand on its own natural ground even without religious belief, and that the coercive enforcement of religious belief by the state must be rejected as a threat to liberty.

I will have the chance to continue this discussion with the Kirkian conservatives when I speak at a Regional Meeting of the Philadelphia Society in Atlanta, Georgia, October 4-5.  The theme of the meeting is "The Permanent Things," and it's a celebration of the 60th anniversary of the publication of The Conservative Mind.  I will be part of a panel on "Human Nature and the Permanent Things."  And I will argue that evolved human nature does provide an enduring, even if not eternal, ground for conservative order.

While indicating my general agreement with Hayek's evolutionary liberalism, I also indicated some points of disagreement--particularly, in his tendency to play up cultural evolution to the exclusion of human nature and human reason, and in his Freudian conception of the free society as requiring a complete suppression of our naturally evolved instincts.

This Hayekian Freudian theme is similar to the idea of "mismatch" coming from the evolutionary psychologists.  As I have already indicated, I find this to be partially true but often exaggerated.  Yes, we are evolved for life in small groups with face-to-face interaction.  But life in small groups is still possible even in the large societies of the modern world.  Moreover, the modern extension of trading relations in global networks of exchange draws on evolved instincts for trading that go back very far into human evolutionary history.

I also questioned the evolutionary psychologists about their commitment to the fact/value distinction.  The presence of Cosmides and Tooby at this conference suggested that they see some connection between evolutionary psychology and classical liberal thought.  And yet they have often said that evolutionary science must be value-free, because moral values are beyond any purely empirical science.  This explains why when Ed Wilson argued for an evolutionary science of morality at the 1996 Meeting of the Human Behavior and Evolution Society, he was fervently criticized by the evolutionary psychologists who insisted that this violated the unbridgeable gap between facts and values, is and ought.  If this is true, then an evolutionary science can contribute very little to classical liberalism as a moral and political position, which would suggest that this whole MPS conference on "Evolution, the Human Sciences, and Liberty" was misconceived!

Ken Minogue's lecture expressed some skepticism about my arguments.  Regrettably, as I have indicated in a previous post, Ken died suddenly during his flight out of the Galapagos at the end of the week, and so I am saddened by the thought that I can't continue my conversations with him.  His lecture seemed to suggest that evolutionary thinking could only subvert traditional moral order.

Various questions were raised in the discussion period.  Some of those questions indicated disagreement with my endorsement of Steven Pinker's argument about the history of declining violence.  For some people in the audience, and for Minogue, it was obvious that "the 20th century was the bloodiest century in human history," and that this was enough to refute Pinker's argument.  As he indicated in his lecture two days later, Deepak Lal thought that Pinker was blind to the fact that the "Long Peace" since World War II has been a product of American imperial dominance of the globe--the Pax Americana.

Thursday, July 18, 2013

The MPS in the Galapagos (5): Charles Murray on Human Nature and Human Diversity

The last lecturer of the day (June 24) was Charles Murray, speaking on "The Rediscovery of Human Nature and Human Diversity".

Murray is an American public policy analyst, who is currently the W. H. Brady Scholar at the American Enterprise Institute in Washington, D.C.  He has written many books on the U.S. welfare state and other public policy issues.  His most recent book is Coming Apart: The State of White America, 1960-2010 (2012), in which he presents evidence for a deep cultural division in white America between a new upper class and a new lower class, a division that apparently has little to do with income inequality and more to do with cultural values.  His best known--and most controversial--book is The Bell Curve: Intelligence and Class Structure in American Life (1994), co-authored with Richard Herrnstein.  In this book, they argued that intelligence is a better predictor of social success in many arenas of life than is one's parents socio-economic status or education.

In much of Murray's writing, one sees a concern about explaining the causes and effects of class structure in American society and a worry that class divisions threaten the American ideal of equality of opportunity in the pursuit of happiness.  One could see that expressed in his lecture at the MPS conference.

Public policy analysts almost universally believe that evolutionary psychology has no application to public policy, Murray observed, because they falsely assume that evolution has not produced an inborn human nature or human diversity.  Against this, Murray stated as the thesis of his lecture that evolutionary psychology will bring a rediscovery of human nature and human diversity as products of human evolution, and that this will produce better public policy.

Murray suggested that the rediscovery of human nature began in 1975 with the publication of two books by two Wilsons at Harvard University--Edward O. Wilson's Sociobiology and James Q. Wilson's Thinking About Crime.  Both argued that a proper understanding of human social problems requires a proper understanding of human nature.  So, for example, if we are trying to understand why intact two-parent families have on average lower rates of child abuse (physical and sexual) than do families of unmarried mothers living with boyfriends, we need to understand the evolutionary reason for this--that men have an evolved natural propensity to care more for their own offspring than they do for the offspring of other men.  This has implications for how we should design public policies related to crime and the protection of children.

Murray suggested that the rediscovery of human diversity has come from the growing evidence for biological diversity expressed as differences by sex and by race.  Men and women really are different on average because of differences in their evolved natural propensities.  And races really are different on average in their genetic profiles.  The genetic basis for racial differences is indicated by studies of single-nucleotide polymorphisms (SNPs) that show patterns of human genetic variation across racial groups.  But although these SNPs naturally sort people into racial groups, Murray observed, we don't know if these genetic differences are important or not.

Despite the difficulty in interpreting these differences, Murray argued, the reality of this human diversity denies one of the most common assumptions of contemporary social thought--the equality premise, which is that people are equal, or nearly so, in their latent abilities and characteristics.

And yet, even as he argued for the importance of recognizing human diversity, Murray insisted that this should not matter for how we treat one another.  "In a rational world, sex and race differences in personality and cognitive profiles truly would not be a big deal," because such differences are only statistical differences in means that should not determine how we judge individuals.  Murray explained: "Genetic sex and race differences become a big deal only when policy tries to pretend they don't exist."

Murray endorsed a quotation from Steven Pinker explaining the true meaning of human equality: "Equality is not the empirical claim that all groups of humans are interchangeable; it is the moral principle that individuals should not be judged or constrained by the average propensities of their group" (18).

While thus rejecting the idea of equality understood as the sameness of all individuals or as requiring equality of outcomes in life, Murray affirmed equality of opportunity--that all individuals should have an equal opportunity to pursue their happiness, with the expectation that such free and equal pursuit of happiness will produce different outcomes for different individuals that will manifest their natural human diversity.

Of all the speakers at the MPS conference, Murray was the one who argued a position most like mine.  The morning after his lecture, I argued that a Darwinian evolutionary account of human nature supported the classical liberalism of Adam Smith.  Almost every point of my argument agreed with what Murray has argued, not only in his MPS lecture but also in two books of political theory--In Pursuit: Of Happiness and Good Government (1988 and 2013) and What It Means to Be a Libertarian (1997).  Indeed, after my lecture, Murray indicated that there was a lot of agreement between us.

I was interested in the reaction of the audience to Murray's lecture, particularly the reaction to his provocative claims about racial diversity.  Although he presented this as supported by evolutionary psychology, some of the most prominent proponents of evolutionary psychology--such as Leda Cosmides and John Tooby--have assumed that while sex differences have deep evolutionary roots, racial differences do not.  This has allowed them to avoid the controversies surrounding the biology of race.  Moreover, Tooby and Cosmides have largely shunned the studies of human biological diversity coming from behavioral genetics.  By contrast, Murray has affirmed human racial diversity in ways that have entangled him in those controversies--as in the debate over The Bell Curve.

As I expected, in the discussion after the lecture, Tooby and Robert Boyd indicated their disagreement with Murray.  They both suggested that while sex differences clearly do have an evolutionary genetic basis, racial differences do not.  Boyd argued that the pattern of genetic differences in human populations shown in the HapMap Project was simply a product of demographic history and geography that did not have deep evolutionary roots. 

Although Murray did not directly answer Tooby and Boyd, I think his answer was implicit in his lecture and paper:  Yes, he might have said, you're right that these racial differences are products of recent demographic history and geography; but that's just the point--they are products of recent biological evolution since the emergence of modern human beings about 50,000 years ago and accelerating since the shift from foraging to farming about 10,000 years ago. 

Evolutionary psychologists like Tooby and Cosmides reject this, because they assume that human genetic evolution stopped about 10,000 years ago, and since then all the evolutionary change has been cultural but not biological, which creates the "mismatch" between human biology and human culture.  (In some of my other posts on Tooby and Cosmides' presentations at the MPS conference, I have indicated my disagreement with their "mismatch" theory.)

I do wish that Murray had clarified one point that might have confused some of his listeners.  Doesn't it sound contradictory to argue, on the one hand, that rediscovering genetic sex and race differences will improve public policy analysis, while also arguing, on the other hand, that such differences are "not a big deal"?

Murray's answer might be found in the last chapter of The Bell Curve, which is entitled "A Place for Everyone."  He opens the chapter with a question: "How should policy deal with the twin realities that people differ in intelligence for reasons that are not their fault, and that intelligence has a powerful bearing on how well people do in life?"  He answers this with a classical liberal argument for equal liberty.  He rejects the answer that government should create the equality of condition, because this would require an egalitarian tyranny contrary to human nature.  "People who are free to behave differently from one another in the important affairs of daily life inevitably generate the social and economic inequalities that egalitarianism seeks to suppress" (532).  But a free people are equal in their equal rights for pursuing happiness in ways that do not coercively interfere with the rights of others pursuing their happiness.  In a society of equal liberty, those individuals who are naturally more intelligent or talented than others will reap the benefits of those superior traits, but those superior individuals will have no right to exploit those of lesser abilities.  In such a society, equal liberty provides the conditions for everyone to find valued places for themselves.

I say something similar to this in my chapter on slavery in Darwinian Natural Right.  The equality of all human beings as possessing a common human nature is fully consistent with the inequality of human beings in their diverse natural endowments.  In spite of the biological variation caused by the genetic uniqueness of each individual, there is a genetic unity to the nature of the human species.  Although human beings are naturally unequal in many respects, they are equal in those minimal emotional and intellectual capacities that sustain a moral sense and thus identify them as members of the human species.  This understanding of human equality requires not equality as identity but equality as reciprocity: although unequal in many respects, all normal human beings will resist exploitation and demand social cooperation based on reciprocal exchange.

If the natural differences between the races were such that the people of one race lacked those minimal emotional and rational abilities that support the moral sense among the people of the other races, then those of the inferior race would be as adapted for slavery as domesticated animals are adapted for domestic service, and those of the enslaved race could properly be treated as perpetual children who would benefit from the direction of human masters.  The people belonging to such an inferior race would accept enslavement with little resistance.

Joaquin Fuster indicated in his lecture that the uniquely human prefrontal cortex that is responsible for our moral freedom of choice does not fully mature until the third decade of life.  This justifies our putting children under the custody of parental guardians.  But we assume that most normal human beings will develop enough cognitive maturity as adults to claim their freedom to live as morally responsible individuals.  If there were a race of humans that did not naturally show this level of cognitive development, they could properly be treated as natural slaves.

Human slavery is wrong because in fact there is no inferior human race like this.  There are natural differences between human races just as there are natural differences between individuals of the same race.  But these natural differences, both racial and individual, do not justify slavery, because they fall within the normal range of variation in the emotional and rational capacities that defines the human species.  Slavery is wrong because it means treating some human beings as if they were not human.