Saturday, July 26, 2014

A new start

When geneticist Davide Piffer examined IQ-enhancing alleles at seven different genes, he found that their average prevalence differed among human populations, being highest in East Asians and lowest in Mbuti Pygmies (photo used with author's approval)


My weekly posts are now appearing on The Unz Review ( By accepting Ron's invitation, I hope to reach a bigger audience and bring myself closer to other writers in the area of human biodiversity. When people work together, or simply alongside each other, minor differences can be ironed out and major differences narrowed or at least accepted good-naturedly. One thing I've learned is that academic debate can leave a legacy of hurt feelings. The impersonal can become personal, partly because people feel attached to their views and partly because views themselves can have personal impacts.

Working together also creates synergy. It becomes easier to identify research priorities, contact interested researchers, and end up with publishable findings. At present, most HBD research involves trawling through the literature and offering new interpretations. That's fine, but we need lab work as well. This point came up in a 2006 interview with geneticist Bruce Lahn:
A lot of researchers studying human population genetics and evolution are strictly data miners (i.e., they generate/publish no original data). There are limitations to such an approach, as it depends on the available data and prevents certain analyses from being performed. Do you expect to see more research groups turning into pure data mining labs in the future? Or will there still be a place for independent labs generating their own data (for example, resequencing a gene in multiple individuals to study the polymorphism)?

Given the explosion of genomic data in the last decade or so, which shows no sign of slowing down any time soon, there is likely to be a proliferation of pure data miners just because there is a niche for them. But I suspect that many interesting findings will still require the combination of data mining and wet experiments to provide key pieces of data not already available in public databases. In this regard, labs that can do both data mining and wet experiments can have an advantage over labs that can only do data mining. (Gene Expression, 2006)

Lab work will probably have to be offshored, not because it's cheaper to do elsewhere but because the "free world" is no longer the best place for unimpeded scientific inquiry.  A Hong Kong team is conducting a large-scale investigation into the genetics of intelligence, and nothing comparable is being done in either North America or Western Europe. Cost isn't the reason.

A few suggestions for research:

Human variation in IQ-enhancing alleles

We know that human intellectual capacity has risen through small incremental changes at very many genes, probably hundreds if not thousands. Have these changes been the same in all populations?

Davide Piffer (2013) has tried to answer this question by using a small subset of these genes. He began with seven SNPs whose different alleles are associated with differences in performance on PISA or IQ tests. Then, for fifty human populations, he looked up the prevalence of each allele that seems to increase performance. Finally, for each population, he calculated the average prevalence of these alleles at all seven genes.

The average prevalence was 39% among East Asians, 36% among Europeans, 32% among Amerindians, 24% among Melanesians and Papuan-New Guineans, and 16% among sub-Saharan Africans. The lowest scores were among San Bushmen (6%) and Mbuti Pygmies (5%). A related finding is that all but one of the alleles are specific to humans and not shared with ancestral primates.

Yes, he was using a small subset of genes that influence intellectual capacity. But you don't need a big number to get the big picture. If you dip your hand into a barrel of differently colored jelly beans, the colors you see in your hand will match well enough what's in the barrel. In any case, if the same trend holds up with a subset of 50 or so genes, it will be hard to say it's all due to chance.

Interaction between age and intellectual capacity

These population differences seem to widen after puberty, as Franz Boas noted a century ago (Boas, 1974, p. 234). It may be that general intelligence was largely confined to early childhood in ancestral humans, as a means to integrate information during the time of life when children become familiar with their surroundings. With increasing age, and familiarity, this learning capacity would shut down. When modern humans began to enter environments that had higher cognitive demands, natural selection may have favored retention of general intelligence in adulthood, just as it favored retention of the capacity to digest lactose wherever adults raised dairy cattle and drank milk.

After doing a principal component analysis on covariance between the above IQ-enhancing alleles and performance on IQ and Pisa tests, Piffer (2013) was able to identify three alleles that show the highest loading on the first component. Ward et al. (2014) have found that possession of these three alleles correlates with educational performance of 13 to 14 year old children. We now have a tool to measure the interaction between genes and age in the development of intellectual capacity, particularly during the critical period extending from pre-puberty to early adulthood.

Convergent evolution

Some human populations seem to have arrived at similar outcomes through different evolutionary trajectories. East Asians, for instance, resemble Western Europeans in their level of societal development, but this similar outcome has been achieved through a different mental and behavioral package, specifically lower levels of guilt and empathy with correspondingly higher levels of shame and prosocial behavior. In short, East Asians tend to enforce social rules more by external mediation (e.g., shaming, peer pressure, family discipline) than by internal control (e.g., guilt, empathy).

This difference probably reflects a mix of learned and innate predispositions, since natural selection favors whatever works, regardless of how hardwired it may or may not be. To the extent that these predispositions are hardwired, East Asians may be less able to cope with the sort of aloneness, anonymity, and individualism we take for granted.

It would be easy enough to study the neurological effects of social isolation on East Asians, and there is already suggestive evidence that such effects include unusual outbursts of psychotic behavior. It would be harder, however, to determine whether this malfunctioning has a heritable component.

Microcephalin - Why does its Eurasian allele increase brain volume?

Almost a decade ago, Bruce Lahn was among those who discovered that a gene involved in brain growth, Microcephalin, continued to evolve after modern humans had spread out of Africa. Its most recent allele arose some 37,000 years ago in Eurasia and is still largely confined to native Eurasians and Amerindians (Evans et al., 2005). Interest in this finding evaporated when no significant correlation was found between the Eurasian allele and higher scores on IQ tests (Mekel-Bobrov et al, 2007; Rushton et al., 2007). Nonetheless, a later study showed that this allele correlates with increased brain volume (Montgomery and Mundy, 2010).

The time of origin corresponds to the entry of modern humans into seasonal temperate environments. It also corresponds to the beginnings of Upper Paleolithic art—realistic 3D representations of game animals on stone, clay, bone, and ivory. The common denominator seems to be an increased capacity to store spatiotemporal information, i.e., the ability to imagine objects, particularly game animals, and how they move over space and time. If IQ tests fail to measure this capacity, it may be worthwhile to test carriers of this allele for artistic or map-reading skills.

ASPM - Does the Middle Eastern/West Eurasian allele assist processing of alphabetical script?

ASPM is another gene that regulates brain growth, and like Microcephalin it continued to evolve after modern humans had spread out of Africa, its latest allele arising about 6000 years ago somewhere in the Middle East. The new allele then proliferated within and outside this region, reaching higher incidences in the Middle East (37-52%) and in Europe (38-50%) than in East Asia (0-25%). Despite its apparent selective advantage, this allele does not seem to improve cognitive performance on standard IQ tests. On the other hand, there is evidence that it is associated with increased brain size (Montgomery and Mundy, 2010).

At present, we can only say that it probably assists performance on a task that exhibited the same geographic expansion from a Middle Eastern origin roughly 6000 years ago. The closest match seems to be the invention of alphabetical writing, specifically the task of transcribing speech and copying texts into alphabetical script. Though more easily learned than ideographs, alphabetical characters place higher demands on mental processing, especially under premodern conditions (continuous text with little or no punctuation, real-time stenography, absence of automated assistance for publishing or copying, etc.). This task was largely delegated to scribes of various sorts who enjoyed privileged status and probably superior reproductive success. Such individuals may have served as vectors for spreading the new ASPM allele (Frost, 2008; Frost, 2011).

Tay Sachs and IQ

Ashkenazi Jews have high incidences of certain neurological conditions, particularly Tay Sachs, Gaucher's disease, and Niemann-Pick disease. In the homozygous state these conditions are deleterious, but in the heterozygous state they may improve intellectual capacity by increasing neural axis length and branching. Cochran et al. (2006) argue that this improvement could amount to about 5 IQ points.

There was in fact a study in the 1980s to determine whether Tay-Sachs heterozygotes suffer from mental deficits (Kohn et al., 1988). The authors found no deficits but did not elaborate on whether performance was above-normal on the neuropsychological tests. They did mention that about two thirds of the Tay-Sachs heterozygotes had education beyond high school.

The raw data seem to be long gone, but it would not be difficult to repeat the study with a view to studying above-normal mental performance in heterozygotes and non-carriers.


Boas, F. (1974). A Franz Boas Reader. The Shaping of American Anthropology, 1883-1911, G.W. Stocking Jr. (ed.), Chicago: The University of Chicago Press. 

Cochran, G., J. Hardy, and H. Harpending. (2006). Natural history of Ashkenazi intelligence, Journal of Biosocial Science, 38, 659-693.  

Evans, P. D., Gilbert, S. L., Mekel-Bobrov, N., Vallender, E. J., Anderson, J. R., Vaez-Azizi, L. M., et al. (2005). Microcephalin, a gene regulating brain size, continues to evolve adaptively in humans, Science, 309, 1717-1720. 

Frost, P. (2008). The spread of alphabetical writing may have favored the latest variant of the ASPM gene, Medical Hypotheses, 70, 17-20.

Frost, P. (2011). Human nature or human natures? Futures, 43, 740-748.  

Gene Expression. (2006). 10 Questions for Bruce Lahn.

Kohn, H., P. Manowitz, M. Miller, and A. Kling. (1988). Neuropsychological deficits in obligatory heterozygotes for metachromatic leukodystrophy, Human Genetics, 79, 8-12. 

Mekel-Bobrov, N., Posthuma, D., Gilbert, S. L., Lind, P., Gosso, M. F., Luciano, M., et al. (2007). The ongoing adaptive evolution of ASPM and Microcephalin is not explained by increased intelligence, Human Molecular Genetics, 16, 600-608.  

Montgomery, S. H., and N.I. Mundy. (2010). Brain evolution: Microcephaly genes weigh in, Current Biology, 20, R244-R246. 

Piffer, D. (2013). Factor analysis of population allele frequencies as a simple, novel method of detecting signals of recent polygenic selection: The example of educational attainment and IQ, Mankind Quarterly, 54, 168-200.  

Rushton, J. P., Vernon, P. A., and Bons, T. A. (2007). No evidence that polymorphisms of brain regulator genes Microcephalin and ASPM are associated with general mental ability, head circumference or altruism, Biology Letters, 3, 157-160.  

Ward, M.E., G. McMahon, B. St Pourcain, D.M. Evans, C.A. Rietveld, et al. (2014). Genetic variation associated with differential educational attainment in adults has anticipated associations with school performance in children. PLoS ONE 9(7): e100248. doi:10.1371/journal.pone.0100248

Saturday, July 19, 2014

From Nazi Germany to Middletown: ratcheting up the war on racism

Licensed under public domain via Wikimedia Commons
Ruth Benedict (1887-1948), much more than Franz Boas, would define the aims of Boasian anthropology for postwar America.


When Franz Boas died in 1942, the leadership of his school of anthropology passed to Ruth Benedict and not to Margaret Mead. This was partly because Benedict was the older of the two and partly because her book Patterns of Culture (1934) had already assumed a key role in defining Boasian anthropology.

The word "define" may surprise some readers. Wasn't Boas a Boasian? Not really. For most of his life he believed that human populations differ innately in their mental makeup. He was a liberal on race issues only in the sense that he considered these differences to be statistical and, hence, no excuse for systematic discrimination. Every population has capable individuals who should be given a chance to rise to the limits of their potential.

He changed his mind very late in life when external events convinced him of the need to fight "racism," at that time a synonym for extreme nationalism in general and Nazism in particular. In 1938, he removed earlier racialist statements from his second edition of The Mind of Primitive Man, and the next year Ruth Benedict wrote Race: Science and Politics to show that racism was more than a Nazi aberration, being in fact an ingrained feature of American life. Both of them saw the coming European conflict as part of a larger war. 

This is one reason why the war on racism did not end in 1945. Other reasons included a fear that extreme nationalism would lead to a second Hitler and a Third World War. How and why was never clear, but the fear was real. The two power blocs were also competing for the hearts and minds of emerging nations in Asia and Africa, and in this competition the West felt handicapped. How could it win while defining itself as white and Christian? The West thus redefined itself in universal terms and became just as committed as the Eastern bloc to converting the world to its way of life. Finally, the rhetoric of postwar reconstruction reached into all areas of life, even in countries like the U.S. that had emerged unscathed from the conflict. This cultural reconstruction was a logical outcome of the Second World War, which had discredited not just Nazism but also nationalism in general, thereby leaving only right-wing globalism or left-wing globalism. Ironically, this cultural change was weaker in the communist world, where people would remain more conservative in their forms of sociality.

Ruth Benedict backed this change. She felt that America should stop favoring a specific cultural tradition and instead use its educational system to promote diversity. To bring this about, she had to reassure people that a journey through such uncharted waters would not founder on the shoals of unchanging human nature. This fear had been addressed in Patterns of Culture (1934). Inspired by Pavlov’s research on conditioned reflexes, she argued that people are conditioned by their culture to think, feel, and behave in a particular way. This pattern assumes over time such a rigid form that even a student of anthropology will assume it to be innate:
He does not reckon with the fact of other social arrangements where all the factors, it may be, are differently arranged. He does not reckon, that is, with cultural conditioning. He sees the trait he is studying as having known and inevitable manifestations, and he projects these as absolute because they are all the materials he has to think with. He identifies local attitudes of the 1930’s with Human Nature […] (Benedict, 1989, p. 9)

She argued that such behavioral traits cannot be innate, since they assume different patterns in different human populations and in different time periods of a single population. Our potential for social change is thus greater than what we imagine, being limited only by the range of behavior that exists across all societies. Because we underestimate this potential, we resist social change on the grounds that it would violate a nonexistent human nature:
The resistance is in large measure a result of our misunderstanding of cultural conventions, and especially an exaltation of those that happen to belong to our nation and decade. A very little acquaintance with other conventions, and a knowledge of how various these may be, would do much to promote a rational social order. (Benedict, 1989, p. 10)

In contradistinction to Boas, who believed that human populations differ innately in various mental and behavioral traits, she argued that cultural evolution had long ago replaced genetic evolution:
Man is not committed in detail by his biological constitution to any particular variety of behaviour. The great diversity of social solutions that man has worked out in different cultures in regard to mating, for example, or trade, are all equally possible on the basis of his original endowment. Culture is not a biologically transmitted complex. (Benedict, 1989, p. 14)

In short, humans have turned the tables on evolution. Instead of being changed by their environment via natural selection, they redesign it with the tools provided by their culture. To a large degree, humans create their own environment:
The human animal does not, like the bear, grow himself a polar coat in order to adapt himself, after many generations, to the Arctic. He learns to sew himself a coat and put up a snow house. From all we can learn of the history of intelligence in pre-human as well as human societies, this plasticity has been the soil in which human progress began and in which it has maintained itself. [...] The human cultural heritage, for better or for worse, is not biologically transmitted. (Benedict, 1989, p. 14)

Since human nature is everywhere the same, whatever works in any other culture ought to work in America’s, and this greater diversity should pose no serious problem. This argument would eventually be topped off by American can-doism: if other cultures can cope with some diversity, we can do even better!
Much more deviation is allowed to the individual in some cultures than in others, and those in which much is allowed cannot be shown to suffer from their peculiarity. It is probable that social orders of the future will carry this tolerance and encouragement of individual difference much further than any cultures of which we have experience. (Benedict, 1989, p. 273)

Such social change would be resisted by Middletown—originally a pseudonym for Muncie, Indiana in two sociological studies, and later a synonym for whitebread small-town America.
The American tendency at the present time leans so far to the opposite extreme that it is not easy for us to picture the changes that such an attitude would bring about. Middletown is a typical example of our usual urban fear of seeming in however slight an act different from our neighbours. Eccentricity is more feared than parasitism. Every sacrifice of time and tranquillity is made in order that no one in the family may have any taint of nonconformity attached to him. Children in school make their great tragedies out of not wearing a certain kind of stockings, not joining a certain dancing-class, not driving a certain car. The fear of being different is the dominating motivation recorded in Middletown. (Benedict, 1989, p. 273)


Ruth Benedict wrote well, so well that any flaws are easily missed. Much of her reasoning revolved around the concept of cultural conditioning. Just as a dog will salivate on hearing the tinkling of a bell, if associated with food, so people will come to respond unthinkingly and in the same way to a situation that occurs over and over again. Such behavior may seem innate, yet it isn't. This part of her reasoning is true, but it is also true that natural selection tends to hardwire any recurring behavioral response. Mental plasticity has a downside, particularly the risks of responding incorrectly to a situation when one is still learning. It's better to get things right the first time. In sum, conditioned reflexes and innate reflexes both have their place, and one doesn't preclude the other ... for either dogs or humans.

Benedict seems on firmer ground in saying that humans are uniquely able to change the world around themselves. Instead of having to adapt biologically to our environment, we can invent ways to make it adapt to us. It's this manmade environment—our culture—that does the evolving, not our genes. This view used to be widely accepted in anthropology and has been proven false only recently. We now know that cultural evolution actually caused genetic evolution to accelerate. At least 7% of the human genome has changed over the last 40,000 years, and most of that change seems to be squeezed into the last 10,000, when the pace of genetic change was more than a hundred-fold higher (Hawks et al., 2007). By that time, humans were no longer adapting to new physical environments; they were adapting to new cultural environments. Far from slowing down genetic evolution, culture has speeded it up by greatly diversifying the range of circumstances we must adapt to.

Benedict was right in foreseeing a time when tolerance would become a virtue. Yet, strangely enough, Middletown America is no more tolerant today than it was in her time. Americans are simply obeying a new set of rules, whose first commandment is now "Thou shalt not be intolerant."  People are still fearful of being different from their neighbours. It's just that the fears have another basis. People are still insulted for being different. It's just that the insults have changed. "Filthy pervert" has given way to "Dirty homophobe." Mistrust of the stranger has been replaced by mistrust of those who are not inclusive. Pierre-André Taguieff has described this new conformity in France:
[...] over the last thirty years of the 20th century, the word "racism" became an insult in everyday language ("racist!" "dirty racist!"), an insult derived from the racist insult par excellence ("dirty nigger!", "dirty Jew!"), and given a symbolic illegitimating power as strong as the political insult "fascist!" or "dirty fascist!". To say an individual is "racist" is to stigmatize him, to assign him to a heinous category, and to abuse him verbally [...] The "racist" individual is thus expelled from the realm of common humanity and excluded from the circle of humans who are deemed respectable by virtue of their intrinsic worth. Through a symbolic act that antiracist sociologists denounce as a way of "racializing" the Other, the "racist" is in turn and in return categorized as an "unworthy" being, indeed as an "unworthy" being par excellence. For, as people say, what can be worse than racism? (Taguieff, 2013, p. 1528)

It's hard to believe that the sin of racism did not yet exist in Ruth Benedict's day. The word itself was just starting to enter common use. At most, there was a growing movement for people to be more tolerant, and even that movement was very limited in its aims. "Tolerance" had a much less radical meaning.

Interestingly, Benedict did touch on the reason for Middletown's intolerance. In her book, The Chrysanthemum and the Sword (1946), she explained that human cultures enforce social rules by means of shame or guilt. You feel ashamed if your wrongdoing is seen by another person. In contrast, you feel guilty even if nobody else has seen it, or even if you merely think about doing wrong. Although all humans have some capacity for both shame and guilt, the relative importance of one or the other varies considerably among individuals and among human populations. "Shame cultures" greatly outnumber "guilt cultures," which are essentially limited to societies of Northwest European origin, like Middletown.

But how does a guilt culture survive? If a few individuals feel no guilt as long as no one is looking, they will have an edge over those who do. Over time, they will proliferate at the expense of the guilt-prone, and the guilt culture will become a shame culture. It seems that this outcome does not happen because the guilt-prone are always looking for signs of deviancy in other individuals, however trifling it may seem. We have here the "broken windows" theory of law enforcement:  if a person tends to break any rule, however minor, he or she will likely break a major one, since the psychological barrier against wrongdoing is similar in both cases. The guilt-prone will judge such people to be morally worthless and will ultimately expel them from the community. Intolerance is the price we pay for the efficiency of a guilt culture.

Today, this mechanism has been turned upon itself. The new social rule—intolerance of intolerance—will, over the not so long term, dissolve the mental makeup that makes a guilt culture possible. Benedict did not foresee this outcome in her own time. Middletown was too set in its ways, too monolithic, too well entrenched. At most, one could hope for a little more leeway for the socially deviant. A few bohemians here, a few oddballs there ...  

Ruth Benedict saw Middletown as a difficult case, particularly its extreme guilt culture, and she drew on the language of education and psychotherapy to frame this difficulty in terms of long-term treatment:
 […] there can be no reasonable doubt that one of the most effective ways in which to deal with the staggering burden of psychopathic tragedies in America at the present time is by means of an educational program which fosters tolerance in society and a kind of self-respect and independence that is foreign to Middletown and our urban traditions. (Benedict, 1989, pp. 273-274)

They [the Puritans] were the voice of God. Yet to a modern observer it is they, not the confused and tormented women they put to death as witches, who were the psychoneurotics of Puritan New England. A sense of guilt as extreme as they portrayed and demanded both in their own conversion experiences and in those of their converts is found in a slightly saner civilization only in institutions for mental diseases. (Benedict, 1989, p. 276)
By the time of her death in 1948, Boasian anthropology had become fully mobilized for the war on racism. This mobilization had begun in response to the rise of Nazi Germany but was soon extended to a much larger enemy that included America itself, as seen in the increasingly radical meanings of “racism” and “tolerance.” Only a determined, long-term effort would bring this enemy to heel.


Benedict, R. (1989 [1934]). Patterns of Culture, Boston: Houghton Mifflin.

Benedict, R. (2005 [1946]). The Chrysanthemum and the Sword. Patterns of Japanese Culture, First Mariner Books.

Hawks, J., E.T. Wang, G.M. Cochran, H.C. Harpending, & R.K. Moyzis. (2007). Recent acceleration of human adaptive evolution. Proceedings of the National Academy of Sciences (USA), 104, 20753-20758.  

Taguieff, P-A. (2013). Dictionnaire historique et critique du racisme, Paris: PUF.

Sunday, July 13, 2014

The Franz Boas you never knew

The anthropologist Franz Boas is remembered for moving the social sciences away from genetic determinism and toward environmental determinism. In reality, he felt that genes do contribute substantially to mental and behavioral differences ... and not just between individuals.

Most of us identify with certain great teachers of the past: Christ, Marx, Freud … Though long dead, they still influence us and we like to think that their teachings have come down to us intact. We know what they believed … or so we like to think. This raises a problem when we find discrepancies. Jesus was so humble that he resented being called good, since only God is truly good. But then ...

Often, however, the discrepancies remain unknown. They develop too gradually for the average person to notice and are most obvious to those who least want to point them out, i.e., the successors of the great teacher. Of course, the great teacher is no longer around to set things straight.

This has happened to many belief-systems. In my last post, I discussed how the real Sigmund Freud differed significantly from the one we know. The same is true for Franz Boas (1858-1942), whose school of anthropology is as much a product of his immediate disciples—Margaret Mead and Ruth Benedict—as of Boas himself.

Today, Boas is remembered as the man who moved the social sciences away from genetic determinism and toward environmental determinism. His Wikipedia entry states:

Boas was one of the most prominent opponents of the then popular ideologies of scientific racism, the idea that race is a biological concept and that human behavior is best understood through the typology of biological characteristics. [...] Boas also worked to demonstrate that differences in human behavior are not primarily determined by innate biological dispositions, but are largely the result of cultural differences acquired through social learning.

In reality, he felt that genes do contribute substantially to mental and behavioral differences ... and not just between individuals. This is apparent in a speech he gave in 1894 under the title "Human Faculty as Determined by Race."

It does not seem probable that the minds of races which show variations in their anatomical structure should act in exactly the same manner. Differences of structure must be accompanied by differences of function, physiological as well as psychological; and, as we found clear evidence of difference in structure between the races, so we must anticipate that differences in mental characteristics will be found.  [...] As all structural differences are quantitative, we must expect to find mental differences to be of the same description, and as we found the variations in structure to overlap, so that many forms are common to individuals of all races, so we may expect that many individuals will not differ in regard to their faculty, while a statistical inquiry embracing the whole races would reveal certain differences. Furthermore, as certain anatomical traits are found to be hereditary in certain families and hence in tribes and perhaps even in peoples, in the same manner mental traits characterize certain families and may prevail among tribes. It seems, however, an impossible undertaking to separate in a satisfactory manner the social and the hereditary features. Galton's attempt to establish the laws of hereditary genius points out a way of treatment for these questions which will prove useful in so far as it opens a method of determining the influence of heredity upon mental qualities (Boas, 1974, p. 239)

We have shown that the anatomical evidence is such, that we may expect to find the races not equally gifted. While we have no right to consider one more ape-like than the other, the differences are such that some have probably greater mental vigor than others. The variations are, however, such that we may expect many individuals of all races to be equally gifted, while the number of men and women of higher ability will differ. (Boas, 1974, p. 242) 

 When discussing brain size, Boaz merely pointed to the overlap among racial groups:

We find that 50 per cent of all whites have a capacity of the skull greater than 1550 cc., while 27 per cent of the negroes and 32 per cent of the Melanesians have capacities above this value. We might, therefore, anticipate a lack of men of high genius, but should not anticipate any great lack of faculty among the great mass of negroes living among whites and enjoying the advantages of the leadership of the best men of that race. (Boas, 1974, pp. 233-234)

He did add that "mental ability certainly does not depend upon the size of the brain alone." He then argued, quoting an authority, that the encephalon and the cortex develop to a greater degree in whites, especially after puberty:

When we compare the capacity for education between the lower and higher races, we find that the great point of divergence is at adolescence and the inference is fairly good that we shall not find in the brains of the lower races the post-pubertal growth in the cortex to which I have just alluded. (Boas, 1974, p. 234)

Boas would return to this topic, such as in this 1908 speech on "Race Problems in America":

I do not believe that the negro is, in his physical and mental make-up, the same as the European. The anatomical differences are so great that corresponding mental differences are plausible. There may exist differences in character and in the direction of specific aptitudes. There is, however, no proof whatever that these differences signify any appreciable degree of inferiority of the negro, notwithstanding the slightly inferior size, and perhaps lesser complexity of structure, of his brain; for these racial differences are much less than the range of variation found in either race considered by itself. (Boas, 1974, pp. 328-329)

All of these remarks must be judged in context. Boaz was trying to stake out a reasonable middle ground in opposition to the view that human races differ not only in degree but also in kind. There is also little doubt about his opposition to racial discrimination, which he felt was holding back many capable African Americans.

But he did not feel that equality of opportunity would lead to equality of results. This was the middle ground he defended, and it is far removed from today's middle ground. The two don't even overlap. What happened between then and now?

Something critical seems to have happened in the late 1930s. When Boas prepared the second edition of The Mind of Primitive Man (1938), he removed his earlier racialist statements. The reason was likely geopolitical. As a Jewish American seeing the rise of Nazi Germany, he may have felt that the fight against anti-Semitism would require a united front against all forms of “racism”—a word just starting to enter common use and initially a synonym for Nazism.

Boas died in 1942 and the leadership of his school of anthropology fell to Ruth Benedict and Margaret Mead. With the end of the war, both of them wished to pursue and even escalate the fight against racism. Escalation was favored by several aspects of the postwar era: lingering fears of a revival of anti-Semitism, competition between the two power blocs for the hearts and minds of the Third World, and an almost utopian desire to rebuild society—be it through socialism, social democracy, or new liberalism … In all this, we are no longer in the realm of science, let alone anthropology. 

Boas had sought to strike a new balance between nature and nurture in the study of Man. The war intervened, however, and Boasian anthropology was conscripted to fight not only the Axis but also racism in any form. Today, three-quarters of a century later, we’re still fighting that war.


Boas, F. (1974). A Franz Boas Reader. The Shaping of American Anthropology, 1883-1911, G.W. Stocking Jr. (ed.), Chicago: The University of Chicago Press. 

Wikipedia (2014). Franz Boas

Friday, July 4, 2014

The origins of guilt: Darwin and Freud

Sigmund Freud (1856-1939) believed that the capacity for guilt varies between individuals and among human populations. He also believed that this variability had, in part, a heritable basis.

Humans are motivated to act correctly by either shame or guilt. We feel shame after acting wrongly in the presence of others. We feel guilt even when no one else sees us acting wrongful or even when we merely think about committing a wrongful act. To varying degrees, all humans seem to have some capacity for both shame and guilt. Most cultures, however, rely primarily on shame and only a minority rely primarily on guilt. In the literature, the distinction between the two is presented as one between non-Western and Western cultures or between collectivistic and individualistic cultures. The capacity for guilt thus seems to be strongest in populations of Northwest European descent.

From the time of Charles Darwin onward, this subject has attracted the interest of several thinkers. How have they explained the origins of shame and guilt?

Charles Darwin

Darwin speculated that shame originated from a universal desire to "save face," which was initially concern about one's personal appearance:

We have seen that in all parts of the world persons who feel shame for some moral delinquency, are apt to avert, bend down, or hide their faces, independently of any thought about their personal appearance. [...] And as the face is the part of the body which is most regarded, it is intelligible that any one ashamed of his personal appearance would desire to conceal this part of his body. The habit, having been thus acquired, would naturally be carried on when shame from strictly moral causes was felt; and it is not easy otherwise to see why under these circumstances there should be a desire to hide the face more than any other part of the body. (Darwin, 1872, p. 123)

Shame, however, is not the same as guilt, and Darwin took care to distinguish between the two when discussing how and why people blush:

With respect to blushing from strictly moral causes, we meet with the same fundamental principle as before, namely, regard for the opinion of others. It is not the conscience which raises a blush, for a man may sincerely regret some slight fault committed in solitude, or he may suffer the deepest remorse for an undetected crime, but he will not blush. "I blush," says Dr. Burgess, "in the presence of my accusers." It is not the sense of guilt, but the thought that others think or know us to be guilty which crimsons the face. A man may feel thoroughly ashamed at having told a small falsehood, without blushing; but if he even suspects that he is detected he will instantly blush, especially if detected by one whom he reveres. (Darwin, 1872, p. 126)

With respect to real shame from moral delinquencies, we can perceive why it is not guilt, but the thought that others think us guilty, which raises a blush. A man reflecting on a crime committed in solitude, and stung by his conscience, does not blush; yet he will blush under the vivid recollection of a detected fault, or of one committed in the presence of others, the degree of blushing being closely related to the feeling of regard for those who have detected, witnessed, or suspected his fault. Breaches of conventional rules of conduct, if they are rigidly insisted on by our equals or superiors, often cause more intense blushes even than a detected crime, and an act which is really criminal, if not blamed by our equals, hardly raises a tinge of colour on our cheeks. (Darwin, 1872, p. 130)

Darwin saw guilt as being not only less universal but also more recent in origin:

The highest possible stage in moral culture is when we recognize that we ought to control our thoughts, and "not even in inmost thought to think again the sins that made the past so pleasant to us." (Darwin, 1936[1888], p. 492)

A few lines further on, he suggested that this kind of mental discipline is "more or less strongly inherited":

There is not the least inherent improbability, as it seems to me, in virtuous tendencies being more or less strongly inherited; for, not to mention the various dispositions and habits transmitted by many of our domestic animals to their offspring, I have heard of authentic cases in which a desire to steal and a tendency to lie appeared to run in families of the upper ranks: and as stealing is a rare crime in the wealthy classes, we can hardly account by accidental coincidence for the tendency occurring in two or three members of the same family. If bad tendencies are transmitted, it is probable that good ones are likewise transmitted. (Darwin, 1936[1888], p. 492)

Has the capacity for guilt been more strongly selected in some human populations than in others? Darwin does not address this question, other than to add:

Except through the principle of the transmission of moral tendencies, we cannot understand the differences believed to exist in this respect between the various races of mankind. (Darwin, 1936[1888], p. 493)

Sigmund Freud

In his work Civilization and Its Discontents (1930), Sigmund Freud argued that guilt was initially a fear of discipline by close kin, particularly one's father. Only later was this fear broadened to include fear of discipline by non-kin, this change being related to the development of larger human communities:

When an attempt is made to widen the community, the same conflict is continued in forms which are dependent on the past; and it is strengthened and results in a further intensification of the sense of guilt. Since civilization obeys an internal erotic impulsion which causes human beings to unite in a closely knit group, it can only achieve this aim through an ever-increasing reinforcement of the sense of guilt. What began in relation to the father is completed in relation to the group. If civilization is a necessary course of development from the family to humanity as a whole, then [...] there is inextricably bound up with it an increase of the sense of guilt, which will perhaps reach heights that the individual finds hard to tolerate. (Freud, 1962, pp. 79-80)

Guilt and shame are two means by which social rules are enforced in large communities where most interactions are no longer with close kin. Shame is enforced by external supervision, i.e., by other people who witness a wrongful act. Guilt is enforced by internal supervision, i.e., by one's conscience, which Freud called the super-ego:

We have also learned how the severity of the super-ego -- the demands of conscience -- is to be understood. It is simply a continuation of the severity of the external authority, to which it has succeeded and which it has in part replaced (Freud, 1962, p. 74)

As the super-ego took over from paternal supervision and discipline, it became not only more important but also more hardwired:

A great change takes place only when the authority is internalized through the establishment of a super-ego. The phenomena of conscience then reach a higher stage. Actually, it is not until now that we should speak of conscience or a sense of guilt. At this point, too, the fear of being found out comes to an end; the distinction, moreover, between doing something bad and wishing to do it disappears entirely, since nothing can be hidden from the super-ego, not even thoughts. It is true that the seriousness of the situation from a real point of view has passed away, for the new authority, the super-ego, has no motive that we know of for ill-treating the ego, with which it is intimately bound up; but genetic influence, which leads to the survival of what is past and has been surmounted, makes itself felt in the fact that fundamentally things remain as they were at the beginning. The super-ego torments the sinful ego with the same feeling of anxiety and is on the watch for opportunities of getting it punished by the external world. (Freud, 1962, p. 72)

The translation is awkward (the original was in German), but he seems to be referring to the heritability of traits that have proven their adaptiveness over time, i.e., "genetic influence, which leads to the survival of what is past and has been surmounted." This heritable component seems to be a capacity, or a willingness, to identify social rules and comply with them, the actual rules being non-innate, i.e., "softwired." This notion of an innate, heritable component comes up again a few pages later:

Experience shows, however, that the severity of the super-ego which a child develops in no way corresponds to the severity of treatment which he has himself met with. The severity of the former seems to be independent of that of the latter. A child who has been very leniently brought up can acquire a very strict conscience. But it would also be wrong to exaggerate this independence; it is not difficult to convince oneself that severity of upbringing does also exert a strong influence on the formation of the child's super-ego. What it amounts to is that in the formation of the super-ego and the emergence of a conscience innate constitutional factors and influences from the real environment act in combination. This is not at all surprising; on the contrary, it is a universal aetiological condition for all such processes. (Freud, 1962, p. 77)

Freud also argued that people differ in their capacity for guilt. In a footnote to the above passage, he explained that the super-ego emerged through "gradual transitions" and thus exists to varying degrees in different people: "[...] it is not merely a question of the existence of the super-ego but of its relative strength and sphere of influence" (Freud, 1962, p. 72). Some individuals are thus extremely guilt-prone:

For the more virtuous a man is, the more severe and distrustful is its [the conscience's] behavior, so that ultimately it is precisely those people who have carried saintliness furthest who reproach themselves with the worst sinfulness. (Freud, 1962, pp. 73-74)

These statements may seem surprising. Didn't Freud believe that neuroses are due to learned inhibitions and that we ought to overcome our inhibitions? Here, however, he argues that both the inhibition of behavior and the expectation of inhibition are instinctual. There has thus been a co-evolution between the internal control mechanism (the super-ego) and human desires (the ego):

The sense of guilt, the harshness of the super-ego, is thus the same things as the severity of the conscience. It is the perception which the ego has of being watched over in this way, the assessment of the tension between its own strivings and the demands of the super-ego. The fear of this critical agency [...] the need for punishment, is an instinctual manifestation on the part of the ego, which has become masochistic under the influence of a sadistic super-ego; it is a portion, that is to say, of the instinct toward internal destruction present in the ego [...] (Freud, 1962, p. 83)

When this control mechanism enters into conflict with human desires, the result is a "conflict between the two primal instincts" (Freud, 1962, p. 84).

We must distinguish between the real Freud and the one of undergrad courses. The latter Freud has become a mouthpiece for beliefs, like rejection of biological determinism and rejection of inhibitions, that did not become dominant until after his death. The real Freud believed that mental and behavioral traits have a substantial heritable basis, as did most scholars of his day. By emphasizing the importance of both nature and nurture, he was in fact taking a very middle-of-the-road position ... for his time. The middle ground would not shift toward environmental determinism until later, with growing interest in the findings of Ivan Petrovich Pavlov and subsequent efforts by the Boasian school of anthropology to explain human behavior in terms of cultural conditioning.

To be continued


Darwin, C. (1936) [1888]. The Descent of Man and Selection in relation to Sex. reprint of 2nd ed., The Modern Library, New York: Random House.

Darwin, C. (1872). The Expression of the Emotions in Man and Animals, London: Murray.

Freud, S. (1962[1930]). Civilization and Its Discontents, New York: W.W. Norton

Saturday, June 28, 2014

How universal is empathy?

Bronislaw Malinowski with natives on the Trobriand Islands (1918 - source). Pro-social behavior seems to be a human universal, but is the same true for full empathy?

What is empathy? It has at least three components:

- pro-social behavior, i.e., actions of compassion to help others

- cognitive empathy, i.e., capacity to understand another person's mental state

- affective or emotional empathy, i.e., capacity to respond with the appropriate emotion to another person's mental state (Chakrabarti and Baron-Cohen, 2013)

In their review of the literature, Chakrabarti and Baron-Cohen (2013) conclude that all three components are moderately to highly heritable, although the affective component seems to show the highest heritability (68%). This is in line with Davis et al. (1994), who found significant heritability for the affective facets of empathy (empathic concern and personal distress) but not for non-affective perspective taking.

All three components can vary from one individual to another, although studies to date have focused on pathological variation:

For example, it is suggested that people with psychopathic personality disorder may have intact cognitive empathy (hence being able to deceive others), but impaired affective empathy (hence being able to hurt others), whilst people with autism may show the opposite profile (hence finding the social world confusing because of their deficit in cognitive empathy, but not being over-represented among criminal offenders, having no wish to hurt others, suggesting their affective empathy may be intact) (Chakrabarti and Baron-Cohen, 2013)

People with depression may suffer from too much empathy, i.e., being too sensitive to the needs or distress of others (O'Connor et al., 2007). In short, these disorders seem to be the tail ends of a normal distribution. By focusing on these extremes, we forget that most of the genetic variability in empathy occurs among healthy individuals (Gillberg, 2007). 

Using research findings on autism and Asperger syndrome, Chakrabarti and Baron-Cohen (2013) have identified nine candidate genes that seem to promote empathy. They fall into three functional categories: sex-steroid synthesis and metabolism; neural development and connectivity; and social-emotional responsivity. The first category includes the degree to which a fetus is androgenized or estrogenized before birth, as shown by digit ratio (Frost, 2014).

Variation among human populations

If the genes associated with empathy vary among healthy individuals, do they also vary among human populations? This would be expected because populations have differed in their needs for different components of empathy, particularly since hunting and gathering gave way to farming some 10,000 years ago—when genetic change speeded up over a hundred-fold. At that time, humans were no longer adapting to new physical environments. They were adapting to new cultural environments that differed in social structure, in division of labor, in means of subsistence, in norms of conduct, in future time orientation, in degree of sedentary living, and so on. Our ancestors were now reshaping their environments, and these human-made environments were now reshaping them—in other words, gene-culture co-evolution (Hawks et al., 2007).

Humans have been transformed especially by the shift from small bands of hunter-gatherers to larger and more complex groups of farmers and townsfolk. With social relations expanding beyond the circle of close kin, kinship obligations were no longer enough to ensure mutual assistance and stop free riding. There was thus selection for pro-social behavior, i.e., a spontaneous willingness to help not only kin but also non-kin.

Pro-social behavior is attested across a wide range of cultures. It is the subject of a recent book about the nature and limits of empathy in Oceanic cultures. The Banabans of Fiji for instance express the idea of pro-sociality through the term nanoanga, which they normally translate into English by "compassion" or "pity."

[...] compassion is the basis for their capacity to bond socially with others, even compassion to the point of readiness to take strangers into their community. Their empathy therefore relates causally to how they act socially toward others. Here compassion or pity embraces both understanding and fellow feeling: the islanders understand that the stranded mariner is at the end of his strength, which is why they succor him and treat him as one of their own. They understand him because he, like them, is a human being, a person. [...] Thus, for example, when someone passing by a house does not belong to the immediate family of those inside, it is customary to welcome the passer-by by calling out the words mai rin! (Come in!), which carry the implication that food and drink will not be found wanting inside. (Hermann, 2011, p. 31)

This desire to help non-kin is not unconditional. The author notes that prior experiences with an individual in distress can determine whether compassion will be given or withheld. Moreover, Barnabans can "proceed strategically when deciding whether to extend trust to others or to keep thoughts and feelings to themselves" (Hermann, 2011, p. 31). This is not the affective empathy of entering another person's mind to feel his or her pain.
When the Barnabans compare themselves with others, and when by their behavior toward the stranger they show that they understand him and feel with him, they do not, however, equate themselves fully and entirely with him. (Hermann, 2011, p. 32)

Another contributor to the same book writes similarly about the inhabitants of Vanatinai, in the Trobriand Islands.
On the island of Vanatinai, when someone, including an ethnographer, privately asks a trusted confidant, "Why did she/he act like that?" "What was she/he thinking?" the common answer, often uttered in tones of puzzlement and despair, or anxiety and fear, expresses one of the islanders' core epistemological principles: "We cannot know their renuanga." Renuanga is a word that refers to a person's inner experiences, both and inseparably thought and emotion.

[...] And their psychic states, their inner thought and feelings, are inherently unknowable. It may never be clear why they were angry or sympathetic, and what caused them to act and influence an event in someone's life [...] (Lepowsky, 2011, p. 44)

In short, Oceanic cultures display hospitality but not full empathy, which would be considered undesirable anyway:

The philosophical principle of personal opacity, the interiority of others' thoughts/feelings (renuanga), is closely bound to the islanders' fierce insistence on personal autonomy, both as cultural ideology and as daily social practice (Lepowsky, 2011, p. 47)


From pro-sociality to full empathy

Whereas pro-sociality is attested across a wide range of cultures, full cognitive/affective empathy is more localized. The difference is like the one we see between shame and guilt. Most cultures primarily use shame to enforce correct behavior, i.e., if other people see you breaking a rule, you feel ashamed and this feeling is reinforced by social disapproval. In contrast, only a minority of cultures—largely those of Northwest Europe—rely primarily on guilt, which operates even when only you see yourself breaking a rule or merely think about breaking a rule (Benedict, 1946; Creighton, 1990).

Northwest Europeans have thus undergone two parallel changes in behavioral control: 1) a shift from pro-sociality to full cognitive/affective empathy; and 2) a shift from shame to guilt. Indeed, full empathy and guilt may be two sides of the same coin. Both are the consequences of a mental model that is used to simulate how another person thinks or feels (an imaginary witness to a wrongful act, a person in distress) and to ensure correct behavior by inducing the appropriate feelings (anguish, pity).

Finally, full empathy and guilt are most adaptive where kinship ties are relatively weak and where rules of correct behavior require a leveling of the playing field between kin and non-kin. This has long been the case in Northwest Europe. There seems to be a longstanding pattern of weak kinship ties west of a line running from Trieste to St. Petersburg, as shown by several culture traits that are rare or absent elsewhere:

- relatively late marriage for men and women

- many people who never marry

- neolocality (children leave the family household to form new households)

- high circulation of non-kin among different households (typically young people sent out as servants) (Hajnal, 1965)

Commonly called the Western European Marriage Pattern, this geographic zone of relatively weak kinship was thought to have arisen after the Black Death of the 14th century. There is now good evidence for its existence before the Black Death and fragmentary evidence going back to 9th century France and even earlier (Hallam, 1985; Seccombe, 1992, p. 94). Historian Alan Macfarlane likewise sees an English tendency toward weaker kinship ties before the 13th century and even during Anglo-Saxon times (Macfarlane, 2012; Macfarlane, 1992, pp. 173-174).

This weak kinship zone may have arisen in prehistory along the coasts of the North Sea and the Baltic, which were once home to a unique Mesolithic culture (Price, 1991). An abundance of marine resources enabled hunter-fisher-gatherers to achieve high population densities by congregating each year in large coastal agglomerations for fishing, sealing, and shellfish collecting. Population densities were comparable in fact to those of farming societies, but unlike the latter there was much "churning" because these agglomerations formed and reformed on a yearly basis. Kinship obligations would have been insufficient to resolve disputes peaceably, to manage shared resources, and to ensure respect for social rules. Initially, peer pressure was probably used to get people to see things from the other person's perspective. Over time, however, the pressure of natural selection would have favored individuals who more readily felt this equivalence of perspectives, the result being a progressive hardwiring of compassion and shame and their gradual transformation into empathy and guilt (Frost, 2013a; Frost, 2013b).

Empathy and guilt are brutally effective ways to enforce social rules. If one disobeys these internal overseers, the result is self-punishment that passes through three stages: anguish, depression and, ultimately, suicidal ideation.

People suffering from depression are looking at both others and themselves with suspicion, often believing whatever they have was obtained by cheating, and that it is more than they deserve. Depressives, burdened by moralistic standards, are harsh evaluators of both themselves and others. The self-punishment meted out by depressives is a common if disturbing symptom; while thinking 'I deserve this', they may engage in altruistic punishment turned upon the self. Just as altruistic punishers experience a neuronally based reward from punishing defectors, despite material costs, depressed patients report a sense of relief upon inflicting self-punishment. Patients who are 'cutters', describe relief from tension after cutting and depressives with suicidal ideation may describe the relief they felt when on the verge of attempting a suicidal action. (O'Connor et al., 2007, p. 67)

This pathology is progressively less common in populations farther south and east, not so much because each stage is less common but rather because depression is much less likely to result from empathic guilt and much less likely to lead to suicide (Stompe et al., 2001). This 3-stage sequence does not seem to be a human universal, at least not to the same extent as in Northwest Europeans, a reality that Frantz Fanon noted when describing clinical depression in Algerians: 

French psychiatrists in Algeria found themselves faced with a difficult problem. When treating a melancholic patient, they were accustomed to being afraid of suicide. The melancholic Algerian kills, however. This disease of the moral conscience that is always accompanied by self-accusation and self-destructive tendencies assumes hetero-destructive forms in the Algerian. The melancholic Algerian does not commit suicide. He kills. (Fanon, 1970, pp. 219-220)



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Chakrabarti, B. and S. Baron-Cohen. (2013). Understanding the genetics of empathy and the autistic spectrum, in S. Baron-Cohen, H. Tager-Flusberg, M. Lombardo. (eds). Understanding Other Minds: Perspectives from Developmental Social Neuroscience, Oxford: Oxford University Press.  

Creighton, M.R. (1990). Revisiting shame and guilt cultures: A forty-year pilgrimage, Ethos, 18, 279-307.

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Fanon, F. (1970). Les damnés de la terre, Paris: Maspero. 

Frost, P. (2013a). The origins of Northwest European guilt culture, Evo and Proud, December 7 

Frost, P. (2013b). Origins of Northwest European guilt culture, Part II, Evo and Proud, December 14  

Frost, P. (2014). A pathway to pro-social behavior, Evo and Proud, May 10.

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