Monday, August 31, 2015

Oliver Sacks, 1933-2015: Natural Teleology in the Clinical Tales of a Philosophic Physician

Oliver Sacks died yesterday from cancer in New York City at the age of 82.  There are two long--and very good--articles about his life in today's New York Times by Michiko Kakutani and Gregory Cowles.

Dr. Sacks was a clinical neurologist, who became famous for his many essays and books with stories about the weirdly enchanting and deeply moving lives of people suffering strange neurological disorders.  He first gained attention with his book Awakenings about a group of patients with an unusual form of encephalitis, or "sleeping sickness," so that they were locked in a catatonic state inside their bodies for over 30 years.  Dr. Sacks gave them the drug L-dopa, and it was as though they awakened back to life, but then months later, they reverted back to their catatonic state.  In the 1990 film "Awakenings," Robin Williams played the part of Dr. Sacks, and Robert De Niro played the part of one of his patients.

The recurrent theme in much of his writing is captured by a quotation from Ivy McKenzie that is one of the epigrams for Dr. Sacks's The Man Who Mistook His Wife for a Hat--"The physician is concerned (unlike the naturalist) . . . with a single organism, the human subject, striving to preserve its identity in adverse circumstances."  One's identity--one's mind or soul--depends, Dr. Sacks indicates, on the activity of one's brain.  And so when that brain becomes disordered, a human being will struggle to preserve his or her personal identity.  The poetic drama of that struggle is what animates Dr. Sacks's stories.

When I first became interested in biopolitical issues, and particularly in the question of whether biological science could support the idea of natural teleology, I was much influenced by the writing of Dr. Sacks and of another philosophic physician--Leon Kass. 

I wrote an article--"Aristotle's Biopolitics: A Defense of Biological Teleology Against Biological Nihilism"--that was published in Politics and the Life Sciences (February 1988).  In defending Aristotle's claim that biological phenomena do show a natural teleology--a striving or inclination towards natural ends or purposes--I pointed to one of Dr. Sacks's cases as illustrating this.  I sent a letter and a copy of my article to Dr. Sacks.  He responded with a long letter.  Cowles reports that Dr. Sacks received about 10,000 letters a year, and he quotes him as saying, "I invariably reply to people under 10, over 90 or in prison."  I am surprised that he replied to me, because I fell into none of those categories!

The case that I used (from The Man Who Mistook His Wife for a Hat) was the story of a patient named Ray, who suffered from Tourette's syndrome.  Those afflicted with Tourette's syndrome are overwhelmed by nervous energy that explodes in jerks, tics, cursing, and a generally weird and comic frenzy.  Apparently these people suffer from an excess of dopamine, which is one of the excitatory transmitters in the brain.  The drug haloperidol ("haldol") can help these people because it decreases the level of dopamine in the brain.

Dr. Sacks found, however, that Ray was reluctant to accept the effects of Haldol.  Having been a Touretter since early childhood, Ray had not only adjusted to his disorder but had exploited the wild and frenetic energy that it provided.  His friends enjoyed his explosive wit.  He was an excellent ping pong player because of his quick and unexpected shots.  He used his fast reflexes to jump into and out of revolving doors with amazing speed.  And as a weekend jazz drummer, he was famous for his frenzied and inventive improvisation.  He spoke of himself as "witty ticcy Ray," known for his "ticcy witticisms and witty ticcisms." He told Dr. Sacks he was not sure he wanted to live without Tourette's syndrome.  (After his first week on Haldol, he had a broken nose caused by a revolving door.)  "Suppose you could take away the tics," he said.  "What would be left?  I consist of tics--there'd be nothing left."  He found that when he was on Haldol, his drumming became dull and lifeless.

He finally decided to compromise.  He would take Haldol during the working week but not on weekends.  From Monday to Friday, he was a calm, conservative member of his community.  But on weekends, he became the frenzied jazz drummer--"witty ticcy Ray."

Ray explained his precarious situation this way:

"Having Tourette's is wild, like being drunk all the while.  Being on Haldol is dull, makes one square and sober, and neither state is really free. . . . You 'normal,' who have the right transmitters in the right places at the right times in your brains, have all feelings, all states, available all the time--gravity, levity, whatever is appropriate.  We Touretters don't: We are forced into levity by our Tourette's and forced into gravity when we take Haldol. You are free, you have a natural balance.  We must make the best of an artificial balance."
According to Dr. Sacks, Ray had achieved a full life "despite being deprived of the birthright of natural freedom which most of us enjoy."

Thus, I argued, Dr. Sacks implicitly assumed in his neurological practice that nature gives us an end to strive for--the health of a normal human brain and mind.  There is a natural order or balance in any normal human life.  Dr. Sacks could therefore recognize Tourette's syndrome as a "disorder" or "disturbance" of the natural functioning that is the healthy condition of a normal human being.  Although in Ray's case, he could not completely repair the damage, he could at least strive for an "artificial balance" that approximated the "natural balance" of normal life.

The standard of health is fixed by nature even if there is flexibility in deciding how best to approximate nature's norm.  Isn't it likely that Ray's subtle understanding of the "natural balance" between gravity and levity reflects Dr. Sacks's wise judgment about what constitutes psychic health?  And doesn't that idea of "natural balance" conform to what Aristotle would call a natural mean between excess and defect?

Sacks in his writing often admired the wondrous insights and exhilaration experienced by people with neurological disturbances.  But he never yielded to the sentimental relativism that would deny the distinction between the normal and the abnormal, the healthy and the diseased.  In short, Sacks assumed, at least implicitly, a teleological conception of living nature.

That's what I said in my article.  But in his letter to me, Sacks intimated that he had changed his mind, and that he was leaning towards what I had dismissed as "the sentimental relativism that would deny the distinction between the normal and the abnormal."  His change of mind had come from his dealing with many Touretters and seeing the individual diversity in how they reacted to their condition. 

He described being in the middle of a conversation in Rotterdam with two Touretters.  One described her Tourette's as giving her a "deep" or "primal" experience, and thus it was a great gift.  But the other Touretter contradicted her by saying that his Tourette's was "completely useless" and a distraction that "took away the deliberative depth of his mind."  (Nietzsche was one of Sacks's favorite philosophers, and I wonder whether he was seeing here Nietzsche's contrast between the Dionysian and the Apollinian.)

Sacks also said, however, that these two Touretters agreed that they would have preferred to be free of Tourette's.  To me that suggests that they did recognize their disease as a disease, and that they were striving to make the best of a bad condition.

On February 19, 2015, the New York Times published an article by Sacks reporting that he had recently learned that he had terminal cancer.  He titled the article "My Own Life," following the title of the short autobiography that David Hume wrote in 1776, just after he had learned of his terminal illness.  Sacks wanted to follow the example of Hume, who wrote: "I now reckon upon a speedy dissolution.  I have suffered very little pain from my disorder; and what is more strange, have, notwithstanding the great decline of my person, never suffered a moment's abatement of my spirits.  I possess the same ardour as ever in study, and the same gaiety in company."

Sacks concluded his essay:
"I cannot pretend I am without fear.  But my predominant feeling is one of gratitude.  I have loved and been loved; I have been given much and I have given something in return; I have read and traveled and thought and written.  I have had an intercourse with the world, the special intercourse of writers and readers."
"Above all, I have been a sentient being, a thinking animal, on this beautiful planet, and that in itself has been an enormous privilege and adventure." 
And thus in facing death, he could take satisfaction in a life well lived as a thinking animal, a life in which he fulfilled some of nature's deepest ends.

Saturday, August 29, 2015

The Biology of Animal Culture Supports Aristotle Against Hobbes

One of the big debates in the history of political philosophy is over the question of whether human beings are political animals by nature comparable to other political animals.  Aristotle said yes, because he thought human beings could be rightly compared with other political animals such as ants, bees, wasps, and cranes.  Hobbes said no, because he thought that while the social insects were instinctively inclined to cooperate for the good of their colony, human political cooperation was learned rather than instinctive, and it had to overcome the natural human tendency to conflict.  Twenty years ago, I argued that modern biological research supported Aristotle's position (Arnhart 1990, 1994, 1998).  The research over the past twenty years provides even more evidence for my argument.

This dispute between Aristotle and Hobbes has been critical for the history of political science.  Most modern political scientists have followed Hobbes in assuming an anthropocentric view of political science, with no comparative study of nonhuman political animals.  In recent years, a few political scientists have revived Aristotle's conception of a biopolitical science as a comparative science that studies all political animals, with human beings understood as the most political animals because of their political use of language or symbolism (logos).

Against Aristotle, Hobbes contended, in both De Cive (chap. 5, par. 5) and the Leviathan (chap. 17), that there were six differences between social animals (like bees and ants) and human beings.  (1) Unlike social animals, human beings compete for honor and prestige. (2) Among social animals, there is no conflict between the private good and the common good, as there is among human beings, because the natural appetites of the social animals incline them as individuals to do what is good for all. (3) Social animals lack reason, which human beings use to criticize the administration of common business and thus create civil conflict. (4) Social animals lack the art of words, which human beings use to argue about what is good and evil and thus fall into sedition and war. (5) Social animals do not distinguish between injury (breach of covenant) and damage; and therefore, unlike human beings, they are not offended with one another as along as their physical appetites are satisfied.  In these five respects, uniquely human attributes create social conflicts not found among the social animals.  A sixth difference between human beings and social animals, according to Hobbes, follows as a consequence of the other five. (6) "Lastly, the agreement of these creatures is natural; that of men, is by covenant only, which is artificial; and therefore it is no wonder if there be somewhat else required, besides covenant, to make their agreement constant and lasting; which is a common power, to keep them in awe, and to direct their actions to the common benefit" (Leviathan, chap. 17).

Hobbes's six arguments presuppose two fundamental premises (compare De Homine, chap. 10).  First, among the naturally social animals, social cooperation is completely harmonious because there are no conflicts of interest to create competition.  Second, nature and instinct are necessarily antithetical to artifice and learning, so that social order cannot be natural or instinctive if it depends in any way on artificial or socially learned activity.  The research done today by Darwinian biologists studying the social behavior of animals denies both premises.

Consider the second premise--the contrast between natural instinct and social learning and the claim that only among human beings does social order depend on social learning.  Aristotle thought that many animals acted not just by unlearned instinct but also by individual and social learning.  Recent studies of animal behavior confirm this.  Among insects, individual learning affects feeding, predator avoidance, social interactions, and sexual behavior (Dukas 2010).  Most insects are solitary, and they show little social learning, except in a few cases such as offspring learning food preferences from their parents.

Social learning is more extensive among social insects, and particularly among the social bees, ants, and wasps (hymenoptera) (Leadbeater and Chittka 2007).  Thus, Aristotle was correct to identify these social insects as political animals.  Today, the most celebrated example of social learning among honeybees is their waggle dance.  Aristotle observed this behavior, and he inferred that it must be some form of social communication.  But it was not until the early 1960s that Karl von Frisch decoded the language of the waggle dance (von Frisch 1967). 

Foraging bees who have found new flower patches return to their nest to recruit their nest mates.  Inside the hive, the forager moves upward while waggling her body from side to side and vibrating her wings.  At the end of each dance, she circles back to the starting point, alternating between clockwise and counterclockwise turns, so that she moves in a figure eight pattern.  The angle of the waggle run relative to the upward direction gives the angle of the flower patch relative to the Sun's position in the sky.  The duration of the dance run is positively correlated to the distance of the flower patch from the hive.  The overall number of waggle runs is positively correlated with the quality of the food in the flower patch.

The same waggle dance is used when honeybees need to decide where to go for a new nest site.  Scouts that have examined a site return to the nest to recruit others to visit the site.  The waggle dance conveys the location and the quality of the potential site.  Different scouts represent different sites.  The better sites recruit more bees to dance for them than the sites of lesser quality.  Eventually, over a period of days, a consensus develops for one site, and the colony moves there.  This is what Tom Seeley calls "honeybee democracy" (Seeley 2010).

It's not clear whether social learning among social insects can create behavioral traditions.  There is some evidence that bees can be trained to forage at certain times of the day, and that once learned, this daily pattern of a colony can be passed down to the next generation of bees (Leadbeater and Chittka 2007).

By contrast to the skimpy evidence for behavioral traditions among social insects, the evidence for socially learned traditions among vertebrates, and particularly chimpanzees, is impressive.  In a famous survey of seven chimp study sites in Africa, it was shown that there were 39 behavior patterns customary in some communities but absent in others, so that each chimp community has its distinctive profile of behavioral patterns, which looks a lot like the cultural diversity of human communities (Whiten et al. 1999).  (As indicated in a previous post, using tools for cracking nuts is one example of a behavioral tradition found in some chimp communities but not others.)

The problem, however, is deciding whether the social learning of behavioral traditions should be identified as "culture," comparable to human culture.  In some previous posts from a few years ago, I have indicated that I have been leaning towards the position of those like Eva Jablonka and Kim Hill (2010), who argue that while the social learning of behavioral traditions is a building block of culture, it is not sufficient, and that human culture is uniquely human insofar as it arises from language and symbolism that can create moral norms supported by moral emotions.

This seems to be Aristotle's position.  On the one hand, some nonhuman animals are political in that they can organize their collective lives through the social learning of behavioral traditions.  On the other hand, human beings are more political than these other political animals, because human beings have a capacity for conceptual abstraction and language (logos) that they can use to formulate and communicate communal standards for the just and the good.  On this  point, Hobbes seems to agree with Aristotle about the uniqueness of human language in allowing human beings to argue about good and evil.

Hill argues that while chimps can have the social regularities of behavioral traditions--such as subordinates deferring to alpha males--only human beings can use symbolic thought and language to create socially recognized norms of good behavior enforced by third-party punishment--such as recognizing that some leaders have the right to rule.

Oddly enough, Hill indicates, the only nonhuman animals that seem to show the third-party enforcement of social norms are honeybees and ants that have individuals who act as "police" in punishing cheaters (Liebig, Peters, and Holldobler 1999; Ratnicks and Wenseleers 2005; Smith, Holldobler & Liebig 2009).

Moreover, the honeybees' waggle dance does seem to be an abstract form of communication that looks like a kind of language.  And yet even this dance language refers to observable realities in the world, and it does not allow bees to conceptualize and agree upon imaginary mental constructions.


Arnhart, Larry. 1990. "Aristotle, Chimpanzees, and Other Political Animals." Social Science Information 29:479-559.

Arnhart. 1994. "The Darwinian Biology of Aristotle's Political Animals." American Journal of Political Science 38:464-485.

Arnhart. 1998. Darwinian Natural Right: The Biological Ethics of Human Nature. Albany: State University of New York Press.

Dukas, R. 2010. "Insect Social Learning." In Michael D. Breed and Janice Moore, eds., Encyclopedia of Animal Behavior, 3 vols., 2:176-179.

Hill, Kim. 2010. "Experimental Studies of Animal Social Learning in the Wild: Trying to Untangle the Mystery of Human Culture." Learning & Behavior 38:319-328.

Leadbeater, Ellouise, and Lars Chittka. 2007. "Social Learning in Insects--From Miniature Brains to Consensus Building." Current Biology 17:R703-R713.

Liebig, J., C. Peeters, and B. Holldobler. 1999. "Worker Policing Limits the Number of Reproductives in a Ponerine Ant." Proceedings of the Royal Society B 266:1865-1870.

Ratnicks, Francis, and Thomas Wenseleers. 2005. "Policing Insect Societies." Science 307:54-56.

Seeley, Thomas. 2010. Honeybee Democracy. Princeton, NJ: Princeton University Press.

Smith, A. A., B. Holldobler, J. Liebig. 2009. "Cuticular Hydrocarbons Reliably Identify Cheaters and Allow Enforcement of Altruism in a Social Insect." Current Biology 19:78-81.

von Frisch, Karl. 1967. The Dance Language and Orientation of Bees. Cambridge: Harvard University Press.

Whiten, A., et al. 1999. "Cultures in Chimpanzees." Nature 399:682-685.

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

Friday, August 28, 2015

The Fourth Edition of "Political Questions" is Now Available

The fourth edition of Political Questions: Political Philosophy from Plato to Pinker (609 pages, $51.95) is now available.  It can be ordered from Amazon or directly from Waveland Press.

The thirteen chapters from the third edition have been extensively revised, including new sections on Hobbes's Behemoth and on Locke's Letter Concerning Toleration.

I have also added three totally new chapters on Adam Smith (The Theory of Moral Sentiments and The Wealth of Nations), Leo Strauss (Persecution and the Art of Writing and Natural Right and History), and Steven Pinker (The Better Angels of Our Nature: Why Violence Has Declined).

If you have followed this blog over the years, you will see material from many of my posts in this new edition.

This book is unique in the way it combines four major features: a reliance on disputed questions, an emphasis on primary texts, references to issues in American political history, and a multidisciplinary approach to political philosophy.

In my surveys of disputed political questions, I bring up pertinent ideas and research from anthropology, biology, economics, history, literature, psychology, and theology.  Thus, students and scholars can see how the study of political philosophy is connected to the study of many intellectual disciplines.  In doing this, I suggest that the history of political philosophy is best studied as part of a multidisciplinary liberal education that aims for a comprehensive science of nature and of human beings as part of nature.

Thursday, August 20, 2015

The Cultural Tradition of Nut-Cracking with Tools Among Chimpanzees

Using stone and wooden tools as anvils and hammers to open nuts is a cultural tradition among some chimpanzees.  A series of YouTube videos of this behavior can be found here. 

Chimpanzees use hammers of stone or wood to crack various species of nuts on anvils of stone or root (McGrew 2004, 119-120).  Soft-shelled nuts can be cracked with wood.  Hard-shelled nuts can be cracked only with stone.  The best stone hammers are carried from one worksite to another.  Nut-cracking is a skilled activity, because the chimp  must apply just the right force in the right way to crack the nuts open.

Using tools for cracking nuts is one of the many behavioral traits that show a cultural diversity among chimpanzees that is comparable to the cultural diversity of humans (Boesch 2012, 219-225; McGrew 2004, 126-128).  Comparing the wild chimpanzee communities across Africa shows that each community has its own distinctive repertoire of behavioral traditions that indicates the cultural history of each community.  Hammer and anvil use is one example of variation in material culture.  Nut-cracking is found only in west Africa, and not at all in central or east Africa.  Most of the nut-cracking is found near the convergence of the borders of eastern Liberia, western Ivory Coast, and southeastern Guinea, which suggests that this cultural tradition was invented in this area and then diffused outward.  Remarkably, the chimpanzees that have been studied for the longest time--those in Gombe and Mahale in east Africa--have never shown a single case of cracking nuts with tools, although the nuts are there, and although the local people use stones to crack nuts.

As McGrew (2004, 126) has suggested this resembles the striking differences in cultural traditions often found among human beings, as in the contrast between the foraging Tasmanians and the aboriginal foragers of the Australian mainland.  The Tasmanians did not have hafted stone tools, bone tools, nets, fish hooks, shields, spear throwers, boomerangs, canoes, or fire-making, although all of this was part of the culture of the Australian foragers.

Some people have argued that the behavioral diversity among the chimpanzee communities in Africa could be a product of differences in the ecological environments or genetic differences between the communities.  But a study of three neighboring communities of chimpanzees in the Tai National Park in the Ivory Coast showed cultural differences in nut-cracking that could not be explained by ecological or genetic differences (Luncz, Mundry, and Boesch 2012).  These three groups live in the same forest environment.  And since females frequently migrate out of their natal groups at maturity to join another group, great genetic differences between the communities are unlikely.  All three communities use hammers to crack nuts, but they differ in their selection of hammer material and hammer size.  During the nut season, the nuts are harder early in the season and softer later in the season.  Harder nuts require stone hammers to open them.  Softer nuts can be opened with wooden hammers, which are more plentiful.  Two of the communities tended to switch from stone hammers to wooden hammers during the season.  But one community tended to stay with stone hammers the entire season, which suggested a distinct cultural tradition of hammer selection.

Human cultural traditions often have a long history, and human tool use can even be traced back into the prehistoric Stone Age.  The same is true for the chimpanzee cultural tradition of tool-use in cracking nuts.  In 1843, there was a report of chimpanzees in west Africa using tools to crack nuts, and this was cited by Darwin in The Descent of Man as evidence for cultural traditions of tool-use among apes (2004, 102-103).  In the 16th and 17th centuries, some Portuguese people reported seeing this in Sierra Leone (Sept and Brooks 1994).  This would suggest that this cultural tradition has been in west Africa for at least 400 years.

Recently, scientists have reported archaeological evidence for chimpanzee sites for cracking nuts with tools that can be dated as at least 4,300 yeas old (Mercader 2007).  The ancient tools at these sites show use-wear patterns and microscopic organic residues that identify them as chimpanzee tools rather than human tools.  This shows how the methods of archaeology used to study the prehistoric human Stone Age can be used to study the prehistoric chimpanzee Stone Age, and from this has emerged a new discipline--"primate archaeology" (Haslam et al. 2009).

The opponents of biopolitical science often argue that the study of primate behavior has no application to human behavior, because only human beings are cultural animals.  Even many of the proponents of biopolitical studies--like John Hibbing and his colleagues--concede that while biology can illuminate the genetic bases of politics, biology has nothing to say about cultural history. 

This research on chimpanzee culture refutes this stance by showing that nonhuman animals do have culture and cultural traditions, and that these cultural traditions are historically contingent.  The study of cultural history is thus as much a part of biology as is genetics.

It is true, however, as I have indicated in various posts, that symbolic evolution is uniquely human, and therefore human culture shows a capacity for symbolic niche construction that chimpanzees and other animals do not have.  I have written about the history of Lockean liberalism as symbolic niche construction. 

A biopolitical science would study political life at four levels: genetic evolution, behavioral cultural evolution, symbolic cultural evolution, and individual political judgment.


Boesch, Christophe. 2012. Wild Cultures: A Comparison Between Chimpanzee and Human Cultures. Cambridge: Cambridge University Press.

Darwin, Charles. 2004. The Descent of Man. 2nd edition. New York: Penguin Classics.

Haslam, Michael, Adriana Hernandez-Aguilar, Victoria Ling, Susana Carvalho, Ignacio de la Torre, April DeStefano, Andrew Du, Bruce Hardy, Jack Harris, Linda Marchant, Tetsuro Matsuzawa, William McGrew, Julio Mercader, Rafael Mora, Michael Petraglia, Helene Roche, Elisabetta Visalberghi, and Rebecca Warren. 2009. "Primate Archaeology." Nature 460:339-344.

Luncz, Lydia, Roger Mundry, and Christophe Boesch. 2012. "Evidence for Cultural Differnces Between Neighboring Chimpanzee Communities." Current Biology 22:922-926.

McGrew, William. 2004. The Cultured Chimpanzee: Reflections on Cultural Primatology. Cambridge: Cambridge University Press.

Mercader, Julio, Huw Barton, Jason Gillespie, Jack Harris, Steven Kuhn, Robert Tyler, and Christope Boesch. 2007. "4,300-Year-Old Chimpanzee Sites and the Origins of Percussive Stone Technology." Proceedings of the National Academy of Science 404:3043-3048.

Sept, Jeanne M., and George E. Brooks. 1994.  "Reports of Chimpanzee Natural History, Including Tool Use, in 16th- and 17th-Century Sierra Leone." International Journal of Primatology 15:867-878.

Thursday, August 13, 2015

Political Assassinations Among Chimpanzees?

On January 7, 1974, six adult chimpanzee males of the Kasakela community in Gombe National Park, Tanzania, attacked as a gang against a lone male from the neighboring Kahama community.  Although the victim was still alive when his attackers left, he was never seen again, and so he was presumed to have died.  One month later, another gang of six Kasakela males brutally attacked another lone male from the Kahama community, who also disappeared and was presumed dead.  Over a period of three years, such attacks led to the extinction of the Kahama community, and the Kasakela community took over the territory of the Kahama community.

When Jane Goodall first reported this violent warfare between two chimpanzee communities, it shocked the world, because Goodall had previously reported that chimpanzees were peaceful--indeed, much more peaceful than human beings.  After years of studying this intercommunity warfare at Gombe, Goodall concluded that this was evidence for an instinctive propensity to warfare in the primate species that is the closest living evolutionary relative of human beings, and thus suggests the possibility that such warfare is an inherited propensity for human beings.  Richard Wrangham, Michael Wilson, and others have elaborated this "chimpanzee model" for explaining the evolution of warfare among human ancestors.

Goodall's observations of chimpanzee intercommunity violence have now been confirmed by similar observations from many chimpanzee communities across Africa.  What is most surprising about this is that lethal violence within chimpanzee communities is extremely rare (Newton-Fisher and Emery Thompson 2012).  Chimpanzees often become aggressive in conflicts with one another, but they usually resolve their conflicts without physical contact; and even if there is some physical violence, it is almost never lethal, even though chimpanzee canines are powerful weapons for wounding and killing victims.  Most aggression between adult males consists of bluffing attacks without physical contact--threatening gestures and vocalizations and charging displays.  (This is also true for human beings, who often engage in bluffing displays of aggression, but for whom homicide is rare, despite the publicity given to homicidal violence.)

After decades of observations of chimpanzee communities across Africa, there have been only four documented cases of lethal violence between adult males of the same community, in which a coalitional gang of adult males killed a lone victim.  Kaburu et al. (2013) point out that the individuals killed in these cases were either low-ranking males or they were previously deposed alpha males.

In the revised edition of his Chimpanzee Politics, Frans de Waal reported that in the summer of 1980, Luit--the alpha male of the chimpanzee community in the Arnhem Zoo in the Netherlands--was attacked brutally and killed by Nikkie and Yeroen, who had previously been alpha males (de Waal 1998, 211-214).  De Waal describes the bloody scene: "Apart from bitting off fingers and toes and causing deep gashes everywhere, the two aggressors removed Luit's testicles, which were found on the cage floor."  This looks like a political assassination.  But it's hard to know whether this case of lethal violence among captive chimpanzees is an abnormal consequence of their captive conditions.  The killing of Luit occurred at night, when the chimps were confined in their night cages.

Kaburu et al. claim to report the first case of lethal violence among wild chimpanzees in which the victim was the incumbent alpha male.  PM was the alpha male of the M-group of chimpanzees in the Malale Mountains National Park in Tanzania when he was killed on October 2, 2011.  He had been the alpha male since 2007.  After a bloody fight between PM and PR, the beta male, PR left.  A weakened PM  was then attacked brutally by a coalition of four other adult males, including two former alpha males (AL and DE).  AL was the alpha male overthrown by PM in 2007.  After the killing, there was a period of social instability.  AL became the alpha male for a short time.  But by November, PR had become the alpha male and is now the alpha male of the M-group.

Kaburu et al. explain this as an opportunistic attempt by AL (the third ranking of 10 adult males) to seize the alpha position once he saw that PM was weakened by the fight with PR, although AL was unable to hold his alpha position for long against the challenge of PR.

When I asked Michael Wilson (a primatologist at the University of Minnesota) about whether there were any other cases of alpha males being killed, he mentioned two cases at Gombe.  Vincent was the alpha male of the Mitumba community at Gombe.  He fell from a tree and severely injured himself.  He lived for another three months before two adult males attacked and killed him.  Michael says he has not yet written a report of this case.

The second case was that of Goblin, another alpha male at Gombe.  He was severely attacked and would have died if a vet had not treated his wounds.  Kaburu et al. mention this case, but they claim that Goblin had been deposed from his alpha position before the attack.

I would like to know more about how common the killing of alpha males might be for chimpanzees and how this compares with the history of political assassinations among human beings.


de Waal, Frans. 1998. Chiampanzee Politics. Revised edition. Baltimore: Johns Hopkins University Press.

Kaburu, Stefano S. K., Sana Inoue, and Nicholas E. Newton-Fisher. 2013. "Death of the Alpha: Within-Community Lethal Violence Among Chimpanzees of the Mahale Mountains National Park." American Journal of Primatology 75:789-797.

Newton-Fisher, Nicholas e. and Melissa Emery Thompson. 2012. "Comparative Evolutionary Perspectives on Violence." In The Oxford Handbook of Evolutionary Perspectives on Violence, Homicide, and War, 41-60. Eds.Todd K. Shackelford and Viviana A. Weekes-Shackelford. Oxford: Oxford University Press.

Some of my posts on chimpanzee politics can be found here, here, here, here, here, and here.

Wednesday, August 12, 2015

The Biopolitical Science of Locke's State of Nature: An APSA Convention Paper

I have written a paper for the 2015 convention of the American Political Science Association in San Francisco, September 3-6.

The paper is "The Biopolitical Science of Locke's State of Nature."  Here's the abstract:

As part of the project for developing a biopolitical science, a biological science of human nature and human history can be used to clarify and perhaps even resolve some of the fundamental debates in the history of political philosophy.  For example, applying biological science to the debate between Hobbes, Locke, and Rousseau over the state of nature can show that Hobbes was partly right, Rousseau was mostly wrong, and Locke was mostly right.  In support of this conclusion, this paper shows how biological science sustains Locke’s account of eight features of the state of nature: human self-ownership, divine ownership, familial society, the law of reputation, egalitarian hierarchy, war and peace, consent to government, and resistance to tyranny. This shows how, as part of a biopolitical science, we can develop a biopolitical philosophy.

My panel will meet on Friday, September 4, 11:30 am to 1:00 pm, at the Hilton San Francisco Union Square, in the room Union Square 21.

Friday, August 07, 2015

The Neurobiology of Self-Ownership: The Self-Awareness of One's Body, One's Agency, and the Social Emotions of Justice

                                                             The Right Insular Cortex

Normally, we are aware that our arms and legs belong to us and not to someone else.  When we move our limbs, we are aware that our limbs are moving, and when we are resting, we are aware that our limbs are not moving.  This self-awareness or self-ownership of our bodies and our agency allows us to distinguish our bodies from the bodies of other people and to identify our actions as different from the actions of others.

It seems strange, therefore, when Rene Descartes says that he could doubt the existence of his body, and therefore the reality of his body as his was not part of his self-evident sense of his own existence as a thinking being without a body.  But, amazingly, there really are people who are not self-aware of their arms and legs or of the movement of their limbs as belonging to them.  They look at one of their arms or legs, and they think this is someone else's limb (Karnath and Baier 2010a, 2010b). 

Oliver Sacks tells the story of a man who woke up in a hospital bed, and when he moved, he felt someone's leg in his bed.  He thought the nurses were playing a cruel joke on him by putting a severed leg in his bed while he slept.  He threw the leg out of the bed.  But when he did this, he somehow came after it.  Falling on the floor, he was shocked to discover that the leg was attached to his body.  He began punching the leg and trying to tear it from his body.  When Sacks arrived, he told the man he shouldn't be punching the leg like that.  "And why not?" the man exclaimed.  "Because it's your leg," Sacks answered.  "Don't you know your own leg?" The man insisted that this was not his leg.  Sacks then asked him, "If this is not your left leg, then where is your own left leg?" The man turned pale.  "I don't know," he said.  "I have no idea.  It's disappeared.  It's gone.  It's nowhere to be found . . ." (Sacks 1985, 53-55).

One possible explanation for this man's condition is that he had suffered damage to the right insular cortex of his brain, causing weakness or paralysis on the left side of his body (hemiparesis or hemiplegia), and that he had lost his self-awareness of his left leg as belonging to him.

The insular cortex is a crucial part of the neural network of the brain that supports self-awareness and self-ownership of one's body and the social emotions in which concern for oneself is extended to concern for others.  In understanding this, social neuroscience provides the evolved biological ground in the brain for what John Locke identified as human self-ownership or self-concern that is extended to concern for others in mammalian animals like humans.

Locke asserts: "Though the Earth, and all inferior Creatures be common to all Men, yet every Man has a Property in his own Person.  This no Body has any Right to but himself" (ST, sec. 27).  "From all which is evident, that though the things of Nature are given in common, yet Man (by being Master of himself, and Proprietor of his own Person, and the Actions or Labour of it) had still in himself the great foundation of Property" (ST, sec. 44).

In his Essay Concerning Human Understanding, Locke identifies a "person" or "self" as "a thinking intelligent being, that has reason and reflection, and can consider itself as itself, the same thinking thing, in different times and places."  All the parts of a human body are vitally united to this thinking self, "so that we feel when they are touched, and are affected by, and conscious of good or harm that happens to them, are a part of ourselves; i.e. of our thinking conscious self."  Consequently, "the limbs of his body are to every one a part of himself; he sympathizes and is concerned for them."  "Self is that conscious thinking thing . . . which is sensible or conscious of pleasure and pain, capable of happiness or misery, and so is concerned for itself, as far as that consciousness extends.  Thus every one finds that, whilst comprehended under that consciousness, the little finger is as much a part of himself as what is most so" (Locke 1959, II.xxvii.9, 11, 17).

Human beings have natural rights to life, liberty, and property, therefore, because they own themselves and thus rightly claim autonomous control of their lives.  And yet, as social mammals who naturally come together in families for sexual mating, conjugal bonding, and parental care of offspring, human beings are naturally inclined to extend their care for themselves to care for others to whom they are attached (FT, secs. 86-89; ST, secs. 54-56, 77-84).

A. D. (Bud) Craig has traced out the fundamental neuroanatomical basis for all human emotions, and he has argued that this shows how the neural substrates for human self-awareness or consciousness are based on the neural representation of the physiological state (the homeostasis) of one's body. This manifests the embodiment of emotional self-consciousness. In particular, he argues that there is a phylogenetically novel sensory pathway in primates, most fully developed in human beings, that provides for a self-conscious integration of the physiological condition of the body (the material "self") with one's sensory environment, with one's motivational condition, and with one's social situation in the anterior insular cortex (AIC) (Craig 2002; 2003; 2008; 2009; 2010a; 2010b).

The evolution of mammalian social behavior depends on the evolution of pain or "negative affect," which includes pain, fear, panic, and anxiety. In all vertebrates, fear and pain are represented in the brainstem and hypothalamus as signals to elicit self-preserving behavior. In mammalian evolution, these neural mechanisms are modified so that animals care for their offspring as well as themselves. This includes modifying the cortex of the mammalian brain to elaborate the representation of pain to include anxiety tied to separation from or threat to loved ones.

Craig's research clarifies this neural evolution of pain by classifying pain as a homeostatic emotion rather than as a sensation of touch. Pain belongs to "interoception"--the sense of the physiological condition of the body--and it is therefore part of the evolved mechanisms for self-preservation.

The insular cortex receives signals from all the tissues of the body, and these signals are integrated with physical and social stimuli from outside the body and with the memory of past experiences as well as imaginative projections of future experiences. This supports a general awareness of the body's condition in space and time. The anterior cingulate cortex (ACC) can then be activated to motivate behavior to correct whatever is wrong. This neural processing mechanism seems to be unique to primates, but it's more highly developed in human beings.

Both the insular cortex and the ACC respond not only to physical pain from bodily injury but also social pain from social injury. It seems that in mammalian evolution, the neural circuitry for physical pain was appropriated for registering social pain in animals adapted for social attachment. Mammals must care for the survival and well-being not only of themselves but of others to whom they are attached. Extending the neural mechanisms originally evolved for individual self-preservation to include the welfare of offspring and social partners secures mammalian social order. The uniquely human evolution of the neocortex elaborates this mammalian development to sustain human love and concern for others.

When we use the language of physical pain to describe our social pain ("a broken heart"), we recognize the embodiment of our natural social consciousness, in which our mind, our brain, our body, and our social life are inseparably intertwined.

The anterior insular cortex (AIC) is involved not only in interoceptive self-awareness but also in the social emotions that support cooperation and fairness (Lamm and Singer 2010).  Observing pain in others activates parts of the neural network that are also activated when we experience pain in ourselves.  Empathy for the pain of others activates the most anterior parts of the AIC, which overlaps with activation related to pain experienced in oneself.  But the activation associated with the experience of pain in oneself encompasses a much larger portion of the insula (including the middle and posterior insular cortex).  To some degree, then, the neural activity for self-concern is extended to concern for others.  But still our self-concern is distinguished from our concern for others.

Brain imaging studies of people playing the Ultimatum Game suggest that a sense of fairness is supported by the AIC and other parts of the brain associated with social emotions, because these neural networks are activated when players decide to defect against unfair but not fair players (Sanfey et al. 2003).  This does not happen when the unfair players are computers, because the human players don't see the computers as intentional agents who can be rightly blamed and punished for their unfairness. 

And thus the AIC is part of a neural network supporting feelings of care and concern for oneself and for others and their welfare that sustains the sense of justice that Locke identifies as "the law of nature" enforced by "the natural executive power of the state of nature" for punishing those who violate that natural law.


A. D. (Bud) Craig. 2002.  "How Do You Feel? Interoception: The Sense of the Physiological Condition of the Body," Nature Reviews Neuroscience 3: 655-666

Craig.  2003. "A New View of Pain as a Homeostatic Emotion," Trends in Neurosciences 26: 303-307

Craig, 2008. "Interoception and Emotion: A Neuroanatomical Perspective," In Handbook of Emotions, 3rd ed., edited by Michael Lewis, Jeannette Haviland-Jones, and Lisa Barrett, 272-288. New York: Guilford.

Craig. 2009. "How Do You Feel--Now? The Anterior Insula and Human Awareness," Nature Reviews Neuroscience 10: 59-70.

Craig. 2010a. "The Sentient Self." Brain Structure and Function 214: 563-577.

Craig. 2010b. "The Insular Cortex and Subjective Awareness." In George Prigatano, ed., Advances in the Study of Anosognosia, 63-87. New York: Oxford University Press.

Karnath, Hans-Otto, and Bernard Baier. 2010a. “Right Insula for Our Sense of Limb Ownership and Self-Awareness of Actions.” Brain Structure and Function 214:411-417

Karnath, Hans-Otto, and Bernard Baier. 2010b. “Anosognosia for Hemiparesis and Hemiplegia: Disturbed Sense of Agency and Body Ownership.” In George P. Prigatano, ed., Advances in the Study of Anosognosia, 39-62. New York: Oxford University Press.

Lamm, Claus, and Tania Singer. 2010. "The Role of Anterior Insular Cortex in Social Emotions." Brain Structure and Function 214:579-591.

Sacks, Oliver. 1985. The Man Who Mistook His Wife for a Hat, and Other Clinical Tales. New York: Summit Books.

Sanfey, A.G., Rilling, J.K., Aronson, J.A., Nystrom, L.E., and Cohen, J.D. 2003. "The Neural Basis of Economic Decision-Making in the Ultimatum Game." Science 300: 1755-1758.

Other posts on these themes can be found here, here, and here.

Wednesday, August 05, 2015

The Evolution of Violent and Nonviolent Resistance to Tyranny: From Foraging Society to the Present

In John Locke's state of nature, all individuals are free and equal because they can punish anyone who tries to bully or tyrannize over them, which Locke calls the "executive power of the state of nature."  For the worst offenders--such as murderers--the natural punishment is death.

Although the threat of such punishment can enforce the social norms of cooperation that constitute the law of nature and that can make the state of nature a state of peace, this state of society without government tends to become a state of war, because, in the absence of formal institutions for establishing, judging, and enforcing laws, people lack any impartial system for the rule of law, and their natural propensity to partiality in judging their own cases leads to violent feuding.  To secure the peace of society, governments are established by the consent of individuals to provide known, settled laws established by formal lawmakers, interpreted by impartial judges, and executed by those entrusted with the natural executive power of the whole society. 

When these powers of government are abused, in being used by the rulers to exploit the ruled contrary to the common good of all, then the people, according to Locke, have the natural right to reclaim the natural executive power for punishing tyrants through overthrowing government and consenting to a new government that is more likely to secure their natural rights.  In their resistance to tyrannical government, people have a natural right to meet force with force, even to the point of killing their rulers.

There are two lines of historical evidence for judging whether Locke is correct about this.  The first is the evidence about the history of human foragers.  The second is the evidence of the history of resistance to tyrannical government.

As I have indicated in previous posts, anthropological studies of the foraging bands that are most likely to resemble our late Pleistocene ancestors indicate that Locke is largely correct in his account of the state of nature as a customary social order in which all individuals had the right to punish deviants.  Punishment included killing, although this was not common, and it was mostly directed against murderers.  The more common forms of punishment were gossip, ridicule, shunning, and physical forms of punishment short of lethal violence.  As Christopher Boehm has shown, foragers enforce their moral norms mostly through what Locke calls the "law of reputation," or what evolutionary theorists call "indirect reciprocity."

The history of political violence and rivalry over governmental rule also shows that people are inclined to exercise their natural right to punish rulers who abuse their powers in tyrannical ways.  In recent years, there have been some rigorously quantitative studies of this history that show a historical pattern of declining political violence and increasing nonviolent resistance to tyranny.

In the first systematic and quantitative study of regicide in Europe, Manuel Eisner (2011) has collected data on the frequency of violent death and regicide among 1,513 monarchs in Europe between AD 600 and 1800.  He has distinguished four categories of violent death: accident, battle death, murder, and legal execution.  He found that in the seventh century, the frequency of regicide was 2,500 murders per 100,000 years in office.  There was a long decline in regicide.  So that by the eighteenth century, the frequency of regicide was about 200 per 100,000 years in office.  By comparison, the homicide rate in Western Europe today is around 0.6-1.5 per 100,000 person-years.  Clearly, then, European kingship before the Industrial Revolution was one of the most dangerous occupations in the world, comparable to that of soldiers in combat.

Eisner found that for most of this history, regicide was carried out within the noble elite in the competition for political rule.  But, then, by the seventeenth century, regicide became increasingly a matter of legal execution--such as the execution of Charles I in 1751 and the execution of Louis XVI in 1793.  In the Glorious Revolution of 1688, James II was deposed without being executed.

The decline in regicide seems to be part of the general historical decline in homicide (Eisner 2003; Pinker 2011).  This general pattern of declining violence seems to be associated with a Hobbesian pacification process, in which the state claims a monopoly on the legitimate use of violence, and with a Lockean liberal culture of bourgeois virtues that arise in modern commercial societies, in which people learn to control their violent impulses for the sake of peaceful economic and social exchange.

While a Hobbesian state can bring peace, it can also bring tyrannical coercion that provokes violent resistance.  And yet, there is some evidence that resistance to Hobbesian tyranny has become more nonviolent.

Erica Chenoweth and Maria Stephan (2008, 2011) entered into a data base all forms of both violent and nonviolent revolutions and reforms since 1900.  Analyzing that data, they found that nonviolent resistance campaigns were more than twice as likely to succeed as violent resistance movements.  Violent resistance is largely limited to young, strong, and violent males.  But the methods of nonviolent resistance--such as strikes, boycotts, and symbolic protests--can recruit a broad array of people. 

And, indeed, as Locke indicated, successful revolutions depend on "people power."  Chenoweth and Stephan were even able to specify that every campaign that achieved the active and sustained participation of just 3.5 percent of the population was successful, and that many succeeded with even less participation.  Every campaign that did surpass the 3.5 percent threshold was nonviolent.

This provides quantitative evidence for Locke's account of government by consent of the governed.  Tyrants cannot rule by themselves.  They need supporters--or what Bruce Bueno de Mesquita and Alastair Smith (2011) call a "minimum winning coalition."  Of course, in a dictatorship, that winning coalition can be a very small elite group of people who receive special benefits from the dictator's rule.  But as Chenoweth and Stephan show, that small group of people supporting the dictator can be persuaded by a small nonviolent resistance movement to turn against the dictator.  Dictators cannot rule without at least the passive acquiescence of the great body of the people, and thus they can be overthrown by the active resistance of 3.5 percent or less of the people, even when that resistance is nonviolent.

So while the exercise of the natural executive power to punish tyrants has often been violent, it can also succeed when it's nonviolent.


Bueno de Mesquita, Bruce, and Alastair Smith. 2011. The Dictator's Handbook: Why Bad Behavior Is Almost Always Good Politics. New York: Public Affairs.

Chenoweth, Erica, and Maria Stephan. 2008. "Why Civil Resistance Works: The Strategic Logic of Nonviolent Conflict." International Security 33: 7-44.

________. 2011. Why Civil Resistance Works: The Strategic Logic of Nonviolent Conflict. New York: Columbia University Press.

Eisner, Manuel. 2003. "Long-Term Historical Trends in Violent Crime." Crime and Justice 30: 83-142.

________. 2011. "Killing Kings: Patterns of Regicide in Europe, AD 600-1800." British Journal of Criminology 51: 556-577.

Pinker, Stephen. 2011. The Better Angels of Our Nature: Why Violence Has Declined.  New York: Viking.

Chenoweth has summarized her research in a TED talk. and a lecture at Dartmouth College.