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May 15, 2017

Reason is but a slave of passions as it always has been

David Hume stated that “reason is, and ought only to be the slave of the passions.” I don’t know about the ought part, that’s up for debate. But the is part seems empirically true. The reasons people give for this or that is often just a post hoc rationalization. To give a different twist to this contention, others have argued that reason exists to win arguments, not converge upon truth. Or more precisely in my opinion to give the patina of erudition or abstraction to sentiments which are fundamentally derived from emotion or manners enforced through group norms (ergo, the common practice of ‘educated’ people citing scholars whose work we can’t evaluate to buttress our own preconceptions; we all do it).

One of the reasons I recommend In Gods We Trust, and cognitive anthropology more generally, to atheists and religious skeptics is that it gives a better empirical window into the mental processes that are really at work, as opposed to those which people say are at work (or, more unfortunately, those they think are at work). In In Gods We Trust the author reports on research conducted where religious believers are given a set of factual assertions purportedly from scholarship (e.g., the Dead Sea Scrolls). These assertions on the face of it flatly contradict their religious beliefs in some deep fundamental way. But when confronted with facts which seem to logically refute the coherency of their beliefs, they often still accept the validity of the scholarship before them. When asked about the impact on their beliefs? Respondents generally asserted that the new facts strengthened their beliefs.

This is one reason that cognitive anthropologists term religious ‘reasoning’ quasi-propositional. It takes the general form of analysis from axioms, but ultimately the rationality is besides the point, it is simply a quiver in the arrow of a broader and deeper cognitive phenomenon.

To give a personal example which illustrates this. Many many years ago I knew a Jewish girl of Modern Orthodox girl background passingly. She once asserted to me that the event of the Holocaust strengthened her belief in her God. I didn’t follow through on this discussion, as it was too disturbing to me. But it brought home to me that in some way the “reasoning” of many religious people leaves me totally befuddled (and no doubt vice versa).

As it happens, while in the course of writing this post, I found out that Hugo Mercier and Dan Sperber, the authors of the above argument in relation to reason and argumentation, published a book last month, The Enigma of Reason. I encourage readers to get it. I just bought a Kindle copy. Dan Sperber, who I interviewed 12 years ago, is a very deep thinker on the level of Daniel Kahneman. He’s French, and his prose can be somewhat difficult, so I wonder if that’s one reason he’s not nearly as well known).

Ultimately the point of this post actually goes back to genomics and history. Anne Gibbons has an excellent piece in Science, There’s no such thing as a ‘pure’ European—or anyone else. In it she draws on the most recent research in human population genomics to refute antiquated ideas about the purity of any given population. If you have read this blog for the past few years you already know most human populations are complex admixtures; that is, it isn’t a human family tree, but a human family graph.

Gibbons’ piece attacks directly some standard racialist talking points which have been refuted on a factual basis by genetic science:

When the first busloads of migrants from Syria and Iraq rolled into Germany 2 years ago, some small towns were overwhelmed. The village of Sumte, population 102, had to take in 750 asylum seekers. Most villagers swung into action, in keeping with Germany’s strong Willkommenskultur, or “welcome culture.” But one self-described neo-Nazi on the district council told The New York Times that by allowing the influx, the German people faced “the destruction of our genetic heritage” and risked becoming “a gray mishmash.”

In fact, the German people have no unique genetic heritage to protect. They—and all other Europeans—are already a mishmash, the children of repeated ancient migrations, according to scientists who study ancient human origins. New studies show that almost all indigenous Europeans descend from at least three major migrations in the past 15,000 years, including two from the Middle East. Those migrants swept across Europe, mingled with previous immigrants, and then remixed to create the peoples of today.

First, let’s set aside the political question of welcoming on the order of one million refugees to Germany. I will not post comments discussing that.

As a point of fact the truth genetically in relation to Germans is even more complex than what Gibbons’ asserts. When I worked with FamilyTree DNA I had access to their database and presented at their year conference some interesting results from people whose four grandparents were from Germany. In short, Germans tended to fall into three main clusters, one that was strongly skewed toward people from some parts of France, another which was shifted toward Scandinavians, and a third which was very similar to Slavs.

The historical and cultural reasons for this are easy to guess at or make conjectures. The takeaway here is that unlike Finns, or Irish, and to a great extent Scandinavians and Britons, Germany exhibits a lot of population substructure within it because of assimilation or migration in the last ~1,000 years. This is why genetically saying someone is “German” is very difficult when compared to saying someone is Polish or Swedish. By dint of their cultural expansiveness Germans are everyone and no one set next to other Northern Europeans* (with the exception perhaps of the French…I’m sure Germans will appreciate this comparison!).

The conceit of these sort of pieces is that racists will confront refutations which will shatter their racist axioms. But since most of the people who are writing these pieces and read Science are not racists, they won’t have a good intuition on the cognitive processes at work for genuine racists.

This causes problems. As a comparison, many atheists seem to think that refutation of the Athanasian creed will blow Christians away and make them forsake their God (or showing them contradictions in the Bible, admit that you’ve gone through that phase!). Though the Church Father Tertullian’s assertion that he “believed because it is absurd” is more subtle than I often make it out to be, on the face of it it does reflect how outsiders view a normative social group like Christianity.

The emphasis here is on normative. Social or religious movements and sentiments are often about norms, which emerge at the intersection of history, intuition, instinct, and facts. I place facts last in the list, because I think it is a defensible stance to take that facts are the least important variable!

The field of cultural evolution has shown that group cohesion and communal norms have been major drivers of human evolution. Likely there has been gene-cultural coevolution so that group conformity has been selected for as a way to make social units operate more smoothly. Social cognition is a thing; people believe what they believe because other people in their social groups believe something, not because they’ve reasoned to it themselves. Originally reasoning is hard. Letting others derive for you, and plugging and chugging is easy. As Muhammad stated, the Ummah will not agree upon error! The smarter people are, the better they are are reasoning…but the better they are at motivated reasoning, ignorance, and rationalization.

When faced with disconfirming evidence some people can dig in and deny the plain facts. Creationists are a straightforward case of this. Then there are evaders.  From what I have seen on the political Left in the United States at least over the last 15 years (when I’ve been engaging actively with people on the internet) there has been a consistent pattern of obfuscation and dodging the likely reality of sex differences in many quarters. When pinned down on the fundamentals few deny the principle or the possibility, but they almost always impose an extremely high level of skepticism that is not found in other domains, where their epistemology is far less stringent.

But then there is a third case, where facts that seem to refute on first blush to you  only strengthen the beliefs of someone with whom you already disagree. I am generally of the view that the rise of naturalistic science has probably undermined the case for classical supernaturalist theism, which emerged in the pre-modern era. Reasonable people can disagree, as I have smart religious friends who are also scientists. Some of these people, like Francis Collins, will even assert that modern findings which boggle the mind and shock our intuitions confirm and strengthen their belief in pre-modern religious systems!

My point is not to take a strong stance on science and religion. Rather, it is to say that when you present evidence and declare “I refute you thus!”, they may simply respond “Aha! You have proven my point!”

In relation to the Gibbons’ article the writing has been on the wall for at least three years, and probably longer. In Towards a new history and geography of human genes informed by ancient DNA Pickrell and Reich content:

…Implicit in this research is the assumption that the geographic locations of people today are informative about the geographic locations of their ancestors in the distant past. However, it is now clear that long-range migration, admixture and population replacement have been the rule rather than the exception in human history. In light of this, we argue that it is time to critically re-evaluate current views of the peopling of the globe and the importance of natural selection in determining the geographic distribution of phenotypes. We specifically highlight the transformative potential of ancient DNA. By accessing the genetic make-up of populations living at archaeologically-known times and places, ancient DNA makes it possible to directly track migrations and responses to natural selection.

Since this was published in spring of 2014 the evidence has gotten stronger and stronger. That is, the distribution of outcomes is getting more consistent and converging to a high confidence truth.

From this, are we to conclude that white nationalism would decline from marginal to non-existent in the past three years? A review of the empirical data does not seem to support that proposition. Therefore, a naive model that white nationalism is predicated on facts about racial purity may be wrong.

The responses that I have seen (often in the form of comments I don’t publish on this weblog) are denial/rejection, confusion, reinterpretation and vindication (along with standard issue racial insults directed toward me, their colored cognitive inferior). As with the religious case I have a difficult time “putting myself” in the shoes of a racialist of any sort, so I don’t totally understand how they’re getting from A to B, but in their own minds they are.

Let’s reaffirm what’s going on here: white racial consciousness in the United States has exploded on the public scene over the past three years, just as scientists have come to the very strong conclusion that the “white European race” as we understand it is an artifact of the last ~5,000 years or so.**

We need to go back to Hume, and the anthropological understanding of what reason is. Reason is a tool to confirm what you already hold to be true and good. If reason falsifies in some way what you hold to be true and good, that does not mean for most people that reason is where they will stand. Likely there will be some subtle reinterpretation, but magically reason will support their presuppositions. Ask the descendants of the followers of William Miller about falsification.

The fact is that very few people in the world know about David Reich and his research. I know this personally because I’m a voluble evangelist, and many geneticists, even human geneticists, are not aware of the revolution in historical population genetics that ancient DNA has wrought. I do not know any Nazis personally, I suspect that perhaps their knowledge of human phylogenomics is not at the same level as a typical geneticist.

Of course this sort of logic about logic cuts both ways. Before 2010 I actually assumed, as did most human geneticists who took an interest in these topics, that human populations had long been resident in their region of current occupation for tens of thousands of years. When I read Reconstructing Indian Population History by David Reich I was shocked out of my prior model, because the inferences were so ingenious and plausible, and, the updated story of how South Asians came to be actually made a lot of anomalies make a lot more sense. When Lazaridis et al. posted Ancient human genomes suggest three ancestral populations for present-day Europeans on biorxiv in the December of 2013 I was far more surprised, because I had always assumed that the thesis that most European ancestry dated to the Pleistocene in any given region was a robust one. Both the phylogeography from mtDNA and Y pointed to a Pleistocene origin.

But the data were compelling. It’s one thing to make inferences on present day genetic distribution, it’s another to actually genotype ancient individuals (remember, I can reanalyze the data myself, and have done so numerous times). Lazaridis et al. and Priya Moorjani’s Genetic Evidence for Recent Population Mixture in India totally changed my personal life. All of a sudden my wife and I were far closer emotionally and spiritually because we understood that the TMRCA of many segments in our autosomal genome was about 5-fold closer than I had assumed!!!***

Actually, the last sentence is a total fiction. The history which changed how I understood my wife and I to be related on a historical population genetic sense had zero impact on our relationship. That’s because we’re not racists, and race doesn’t really impact our relationship too much (the fact that my parents are Muslim, well, that’s a different issue….). Sorry Everyday Feminism. This is not an uncommon view, though perhaps not as common as we’d assumed of late (actually, as someone who has looked at the fascinating interracial dating research, I pretty much understood that what people say is quite different than what they do; anti-racism is the conformist thing to do, so people will play that tune for a while longer).

Just because the state of the world is one particular way, it does not naturally follow that it should be that way, or that it always will be that way. Most ethical religions saw in slavery an aspect of injustice; rational arguments aside, on some level extension of empathy and sympathy makes its injustice self-evident. But they accepted that it was an aspect of the world that was naturally baked into the structure of reality. The de jure abolition of slavery today does not mean it has truly gone away, but its practice has certainly been curtailed, and much of the cruelty diminished. Theories of human nature or necessities of economic production at the end of the day gave way changing mores and values. Facts about the world became less persuasive when we decided to let them no longer dictate tolerance of slavery.

All that I say above in relation to how humans use reason does not leave scientists or journalists untouched. All humans have their own goals, and even though they see through the glass darkly, they see in the visions beyond what they want to see. The cultural and theoretical structure of modern science is such that some of these impulses are dampened and human intuitions are channeled in a manner so that theories and models of the world seem to correspond to reality. But I believe this is deeply unnatural, and also deeply fragile. When moving outside of their domain of specialty scientists can be quite blind and irrational. Even when one steps away at a mild remove in terms of domain knowledge this becomes clear, such as when Linus Pauling promoted Vitamin C. And motivated reasoning can creep into the actions of even the greatest of scientists, such as when R. A. Fisher rejected the causal connection between tobacco and cancer.****

I will end on a frank and depressing note: I believe that the era of public reason and fealty to empirical standards in at least official capacities is fading. Social cognition, tribal logic, is on the rise. But we have to remember that in the historical perspective social cognition and tribal logic ruled the day. They are the norm. This is age when he abide by public reason is the peculiarity in the sea of polemic. Ultimately it may be the fool who fixates on being right or wrong, as opposed to being on the winning team. I hope I’m wrong on this.

Addendum: I have written a form of this post many times.

* The current chancellor of Germany has a Polish paternal grandfather.

** If Middle Easterners are included as white we can extended the time horizon much further back, but that seems to defeat the purpose of white nationalism in the United States….

*** I had assumed that the western affinity in South Asians had diverged from Europeans during the Last Glacial Maximum. In turns out some of it may be as recent as ~4,500 years ago or so.

**** This may have been unconsciously as opposed to malicious, as Fisher was keen on tobacco personally.

May 29, 2012

Reason: the God that fails, but we keep socially promoting….

Filed under: Anthroplogy,Cognitive Science,Psychology — Razib Khan @ 12:03 pm

One point which I’ve made on this weblog several times is that on a whole range of issues and behaviors people simply follow the consensus of their self-identified group. This group conformity probably has deep evolutionary origins. It is often much cognitively “cheaper” to simply utilize a heuristic “do what my peers do” than reason from first principles. The “wisdom of the crowds” and “irrational herds” both arise from this dynamic, positive and negative manifestations. The interesting point is that from a proximate (game-theoretic rational actor) and ultimate (evolutionary fitness) perspective ditching reason is often quite reasonable (in fact, it may be the only feasible option if you want to “understand,” for example, celestial mechanics).

If you’re faced with a complex environment or set of issues “re-inventing the wheel” is often both laborious and impossible. Laborious because our individual general intelligence is simply not that sharp. Impossible because most of us are too stupid to do something like invent calculus. Many people can learn the rules for obtaining derivatives and integrals, but far fewer can come up with the fundamental theorem of calculus. Similarly, in the 18th century engineers who utilized Newtonian mechanics for practical purposes were not capable ...

Reason: the God that fails, but we keep socially promoting….

Filed under: Anthroplogy,Cognitive Science,Psychology — Razib Khan @ 12:03 pm

One point which I’ve made on this weblog several times is that on a whole range of issues and behaviors people simply follow the consensus of their self-identified group. This group conformity probably has deep evolutionary origins. It is often much cognitively “cheaper” to simply utilize a heuristic “do what my peers do” than reason from first principles. The “wisdom of the crowds” and “irrational herds” both arise from this dynamic, positive and negative manifestations. The interesting point is that from a proximate (game-theoretic rational actor) and ultimate (evolutionary fitness) perspective ditching reason is often quite reasonable (in fact, it may be the only feasible option if you want to “understand,” for example, celestial mechanics).

If you’re faced with a complex environment or set of issues “re-inventing the wheel” is often both laborious and impossible. Laborious because our individual general intelligence is simply not that sharp. Impossible because most of us are too stupid to do something like invent calculus. Many people can learn the rules for obtaining derivatives and integrals, but far fewer can come up with the fundamental theorem of calculus. Similarly, in the 18th century engineers who utilized Newtonian mechanics for practical purposes were not capable ...

September 20, 2011

God is intuitive

Filed under: Anthroplogy,atheism,Cognitive Science,Psychology,Religion — Razib Khan @ 10:15 pm

Update: An ungated version of the paper.

I used to spend a lot more time talking about cognitive science of religion on this weblog. It was an interest of mine, but I’ve come to a general resolution of what I think on this topic, and so I don’t spend much time discussing it. But in the comments below there was a lot of fast & furious accusation, often out of ignorance. I personally find that a little strange. I’ve been involved in freethought organizations in the past, and so have some acquaintance with “professional atheists.” Additionally, I’ve also been a participant and observer of the internet freethought websites since the mid-1990s (yes, I remember when alt.atheism was relevant!). In other words, I know of whom I speak (and I am not completely unsympathetic to their role in the broader ecology of ideas).

But the bigger issue is a cognitive model of how religiosity emerges. Luckily for me a paper came out which speaks to many of the points which I alluded to, Divine intuition: Cognitive style influences belief in God:

Some have argued that belief in God is intuitive, a natural (by-)product of the human mind given its cognitive structure and social context. If this is true, the extent to which one believes in God may be influenced by one’s more general tendency to rely on intuition versus reflection. Three studies support this hypothesis, linking intuitive cognitive style to belief in God. Study 1 showed that individual differences in cognitive style predict belief in God. Participants completed the Cognitive Reflection Test (CRT; Frederick, 2005), which employs math problems that, although easily solvable, have intuitively compelling incorrect answers. Participants who gave more intuitive answers on the CRT reported stronger belief in God. This effect was not mediated by education level, income, political orientation, or other demographic variables. Study 2 showed that the correlation between CRT scores and belief in God also holds when cognitive ability (IQ) and aspects of personality were controlled. Moreover, both studies demonstrated that intuitive CRT responses predicted the degree to which individuals reported having strengthened their belief in God since childhood, but not their familial religiosity during childhood, suggesting a causal relationship between cognitive style and change in belief over time. Study 3 revealed such a causal relationship over the short term: Experimentally inducing a mindset that favors intuition over reflection increases self-reported belief in God.

Recall that in many social domains where neurotypicals rely on innate, intuitive, and “fast” cognition, high functioning autistic individuals must reflect and reason. I don’t have access to the original paper, but there’s a nice piece in Harvard Gazette on the research. Here’s the last sentence: ““How people think about tricky math problems is reflected in their thinking — and ultimately their convictions — about the metaphysical order of the universe,” Shenhav said.”

August 6, 2011

Real life interaction is a feature, not a bug

Filed under: Cognitive Science,Facebook,Google,Social web,Technology,twitter — Razib Khan @ 12:03 pm

The prince of neurobloggers Jonah Lehrer has a good if curious column up at the Wall Street Journal, Social Networks Can’t Replace Socializing. He concludes:

This doesn’t mean that we should stop socializing on the web. But it does suggest that we reconsider the purpose of our online networks. For too long, we’ve imagined technology as a potential substitute for our analog life, as if the phone or Google+ might let us avoid the hassle of getting together in person.

But that won’t happen anytime soon: There is simply too much value in face-to-face contact, in all the body language and implicit information that doesn’t translate to the Internet. (As Mr. Glaeser notes, “Millions of years of evolution have made us into machines for learning from the people next to us.”) Perhaps that’s why Google+ traffic is already declining and the number of American Facebook users has contracted in recent months.

These limitations suggest that the winner of the social network wars won’t be the network that feels the most realistic. Instead of being a substitute for old-fashioned socializing, this network will focus on becoming a better supplement, amplifying the advantages of talking in person.

For years now, we’ve been searching for ...

February 3, 2011

Descartes’ Baby: How The Science Of Child Development Explains What Makes Us Human

Link to review: Inducing Disgust

The Robot’s Rebellion: Finding Meaning in the Age of Darwin

Link to review: The God of Reason

September 27, 2010

American family values: where even the dull can dream!

ResearchBlogging.orgOne of the issues when talking about the effect of environment and genes on behavioral and social outcomes is that the entanglements are so complicated. People of various political and ideological commitments tend to see the complications as problems for the other side, and yet are often supremely confident of the likely efficacy of their predictions based on models which they shouldn’t even been too sure of. That is why cross-cultural studies are essential. Just as psychology has overly relied on the WEIRD nature of data sets, so it is that those interested in social science need to see if their models are robust across cultures (I’m looking at you economists!).

That is why this ScienceDaily headline, Family, Culture Affect Whether Intelligence Leads to Education, grabbed my attention. The original paper is Family Background Buys an Education in Minnesota but Not in Sweden:

Educational attainment, the highest degree or level of schooling obtained, is associated with important life outcomes, at both the individual level and the group level. Because of this, and because education is expensive, the allocation of education across society is an important social issue. A dynamic quantitative environmental-genetic model can help document the effects of social allocation patterns. We used this model to compare the moderating effect of general intelligence on the environmental and genetic factors that influence educational attainment in Sweden and the U.S. state of Minnesota. Patterns of genetic influence on educational outcomes were similar in these two regions, but patterns of shared environmental influence differed markedly. In Sweden, shared environmental influence on educational attainment was particularly important for people of high intelligence, whereas in Minnesota, shared environmental influences on educational attainment were particularly important for people of low intelligence. This difference may be the result of differing access to education: state-supported access (on the basis of ability) to a uniform higher-education system in Sweden versus family-supported access to a more diverse higher-education system in the United States.

Minnesota is to some extent the Scandinavia of America, so the cross-cultural difference is particularly notable. You wouldn’t be surprised for example by big differences between Mississippi and Sweden. But looking at a comparison between the Upper Midwest and Scandinavia is closer to seeing the impact of national culture and policy differences on populations which were originally very similar.

Their methodology was simple, though as with much of this sort of behavior genetic work the statistical analysis can be somewhat labored. In both Sweden and Minnesota you had samples of dizygotic and monozygotic twins which give you a way to compare the effect of genes on variation in life outcomes. Sweden has large data sets from male conscription for behavior genetics analysis. They compared this with the Minnesota Twin Family Study data set.

Since the topline results are pretty straightforward, I thought I’d give you some statistics. Table 1 has raw correlations. Note that they converted educational attainment into a seven-point scale, less than 9 years of education to completion of doctoral studies.


You see the expected drop off in correlation between identical and fraternal twins. Identical twins share more genetic identity than fraternal twins, so they’re going to be more identical on a host of metrics aside from appearance. Those are just raw correlation values of traits though across categories of twins. The core intent of the paper was to explore the relationship between genes, family environment, and other environmental factors, and educational attainment. To do this they constructed a model. Below you see estimates of the variance in the trait explained by variance in genes, shared environment (family), non-shared environment (basically “noise” or error, or it could be something like peer group), from Sweden to Minnesota, and, at three intelligence levels. Two standard deviations below the norm is borderline retarded, ~2.5% of the population or so, and two standard deviations above the norm is at Mensa level.


It’s interesting that as you move up the IQ scale the genetic variation explains more and more of variance the educational attainment. Someone with an IQ of 130 is likely to be university educated. But there are many who are not. Why? The way I interpret these results is that if you are that intelligent and do not manage to complete university you may have heritable dispositions of personality which result in you not completing university. If, for example, you come from a family which is very intelligent, but is low on conscientiousness, then there may be a high likelihood that you just won’t complete university because you can’t be bothered to focus. Or, you may have personality characteristics so that you don’t want to complete university. A second major finding here is that Sweden and the USA go in totally different directions when it comes to the sub-average and dull in prediction of years of education. Why? The explanation in the paper seems plausible: Sweden strongly constrains higher education supply, but makes it available to those with proven academic attainments at a nominal price. Family encouragement and connections don’t matter as much, if you can’t pass the university entrance examination you can’t pass it. In contrast in the USA if you’re dull, but come from a more educated or wealthier family, you can find some university or institution of higher education which you can matriculate in. Supply is more flexible to meet the demand. I actually know of a woman who is strongly suspected to be retarded by her friends. I have been told she actually tested in the retarded range in elementary school but was taken out of that  track because her family demanded it (she’s the product of a later conception, and her family made their money in real estate, not through professional advancement). Over the years she has enrolled in various community colleges, but never to my knowledge has she completed a degree. If she had not had family connections there is a high probability she wouldn’t have completed high school. As it is, she can check off “some college” on demographic surveys despite likely be functionally retarded.

The next table is a bit more confusing. It shows you the correlations between the effects of the variable on education and intelligence. In other words, does a change in X have the same directional effect on Y and Z, and what is the extent of the correspondence between the effect on Y and Z.


Shared environment had almost the same effect on intelligence and education, while genetics had a more modest simultaneous effect. Not too surprising that non-shared environment didn’t have a strong correlation in effect across the traits, the authors note that much of this is going to noise in the model, and so not systematically biased in any direction. Though the confidence intervals here are a little strange. I’m not going to get into the details of the model, because frankly I’m not going to replicate the analysis with their data myself. That’s why I wanted to present raw correlations first. That’s pretty straightforward. Estimates of variances out of models with a set of parameters is less so. Here’s an interesting point from the correlations in the last table:

The patterns of genetic correlations in the two samples differed. In Sweden, genetic correlation was steadily in excess of .50 across the range of intelligence, indicating a genetically influenced direct effect of intelligence on educational attainment that was weaker than the shared environmental effect on educational attainment. In the MTFS [Minnesota] population, however, genetic correlation was in excess of .50 when level of intelligence was low, but was halved at higher levels of intelligence. This indicated that genetic influences on intelligence tended to limit educational attainment when the level of intelligence was low, but not when the level of intelligence was average or high.

Now let me jump to conclusion:

This finding indicates that genetic influences common to intelligence and educational attainment may have been more effective in limiting educational attainment in individuals with low levels of intelligence than in encouraging educational attainment in those with high levels of intelligence. As in Sweden, shared environmental influences on intelligence and educational attainment were completely linked, indicating a direct contribution from shared environmental influences on intelligence to educational attainment. The decrease in shared environmental variance with higher intelligence, however, indicated that shared environmental influences were more effective in encouraging educational attainment in higher-intelligence individuals than in limiting educational attainment in lower-intelligence individuals. In other words, in populations in which shared environmental influences such as family history and values encouraged high levels of educational attainment, individuals were able to surmount limitations in intelligence.

Our analysis does not permit the conclusion that these differences in educational systems cause the differences in environmental and genetic influences on educational attainment observed in this study, but it is reasonable to hypothesize that this is likely. In particular, the greater expense of higher education and greater subjectivity of admission standards in the United States compared with Sweden may partially explain the very different patterns of shared environmental influences in the two population samples. Regardless of the causes underlying the differences we observed, the results of our study make clear that the degrees of environmental and genetic influences can vary substantially between groups with different circumstances, and even within such groups. Our results also suggest that the ways in which social systems are organized may have implications for how and to what extent environmental and genetic influences on behavior will be expressed.

This discussion about the role of environment, genes, and culture, on various outcomes should not hinge on one paper. But, these sorts of results are often not widely disseminated among the intellectual classes. One aspect of the American educational system in contrast to some other nations is that not-too-brights have university degrees. Education has long been a project for social engineering in the USA, going back to Horace Mann. Legacies, underrepresented minorities, the poor, those with particular talents, etc., are all part of the decentralized system of university admissions in the United States. In contrast, in nations such as Sweden or Japan there is a more centralized and universal set of criteria. This results is more perfect sorting by the metrics of interest without considerations of social engineering. I know that Sweden has traditionally had a small aristocratic class, while the Japanese aristocracy were basically abolished after World War II. Additionally, both are relatively homogeneous societies so considerations of racial representativeness are not operative. Or weren’t until recently in the case of Sweden. But consider one reality: if such a system is perfectly meritocratic over time if the traits being evaluated are heritable then you will have genetic stratification and reduction of social mobility assuming assortative mating at university.

Currently there is some handwringing by the elites about the fact that so few poor kids get admitted to Ivy League universities. I think there’s a simple way to change this: get rid of the implicit Asian quotas. After all, there was a lot of socioeconomic diversity after the Ivy League universities got rid of their Jewish quotas, but the children of the Jews who didn’t have to go to CUNY and went to Harvard are well off themselves. But more socioeconomic mobility through removing the implicit Asian quota would cause other difficulties, as elite private universities need their slots for both legacies as well as underrepresented minorities for purposes of social engineering/fostering diversity/encouraging donations. Additionally, just as with the Jews the welter of mobility in one generation of the children of Asian immigrants would settle into quiescence in the next if the traits which enable university admission are genetically or culturally heritable.

Citation: Johnson W, Deary IJ, Silventoinen K, Tynelius P, & Rasmussen F (2010). Family background buys an education in Minnesota but not in Sweden. Psychological science : a journal of the American Psychological Society / APS, 21 (9), 1266-73 PMID: 20679521

April 13, 2010

Mirror neurons reemerge

Filed under: Cognitive Science,Mirror Neurons,science — Razib Khan @ 7:52 am

A few years ago I was hearing a lot about mirror neurons. There was a hyped up article on The Edge website about them, MIRROR NEURONS and imitation learning as the driving force behind “the great leap forward” in human evolution. But I haven’t heard much since then, though I’m not neuro nerd so perhaps I’m out of the loop. So I pass on this link with interest, Single-Neuron Responses in Humans during Execution and Observation of Actions:

Direct recordings in monkeys have demonstrated that neurons in frontal and parietal areas discharge during execution and perception of actions…Because these discharges “reflect” the perceptual aspects of actions of others onto the motor repertoire of the perceiver, these cells have been called mirror neurons. Their overlapping sensory-motor representations have been implicated in observational learning and imitation, two important forms of learning [9]. In humans, indirect measures of neural activity support the existence of sensory-motor mirroring mechanisms in homolog frontal and parietal areas…other motor regions…and also the existence of multisensory mirroring mechanisms in nonmotor region…We recorded extracellular activity from 1177 cells in human medial frontal and temporal cortices while patients executed or observed hand grasping actions and facial emotional expressions. A significant proportion of neurons in supplementary motor area, and hippocampus and environs, responded to both observation and execution of these actions. A subset of these neurons demonstrated excitation during action-execution and inhibition during action-observation. These findings suggest that multiple systems in humans may be endowed with neural mechanisms of mirroring for both the integration and differentiation of perceptual and motor aspects of actions performed by self and others.

ScienceDaily has a hyped-up headline, First Direct Recording Made of Mirror Neurons in Human Brain.

Update: Neuroskepticcritic has much more.

March 18, 2010

We be symbolic

Filed under: Cognitive Science — Gene Expression @ 1:25 am

The Evolution Of Symbolic Language by Terrence Deacon and Ursula Goodenough. Deacon's The Symbolic Species: The Co-Evolution of Language and the Brain is a book I liked a great deal, though in hindsight I don't think I had the background to appreciate it in any depth (nor do I now).

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We be symbolic

Filed under: Cognitive Science — Razib Khan @ 1:25 am

The Evolution Of Symbolic Language by Terrence Deacon and Ursula Goodenough. Deacon’s The Symbolic Species: The Co-Evolution of Language and the Brain is a book I liked a great deal, though in hindsight I don’t think I had the background to appreciate it in any depth (nor do I now).

February 25, 2010

Anthropology as a dog side-effect skill

Filed under: Cognitive Science — Gene Expression @ 1:36 pm

Social Cognition in Dogs, or How did Fido get so smart?. This you know:

Domesticated dogs seem to have an uncanny ability to understand human communicative gestures. If you point to something the dog zeroes in on the object or location you're pointing to (whether it's a toy, or food, or to get his in-need-of-a-bath butt off your damn bed and back onto his damn bed). Put another way, if your attention is on something, or if your attention is directed to somewhere, dogs seem to be able to turn their attention onto that thing or location as well.

Amazingly, dogs seem to be better at this than primates (including our nearest cousins, the chimpanzees) and better than their nearest cousins, wild wolves.

But there are two explanations for how/why dogs are better than primates at this task:

And so it was that biological anthropologist Brian Hare, director of the of Duke University Canine Cognition Center wondered: did dogs get so smart because of direct selection for this ability during the domestication of dogs, or did this apparent intelligence evolve, in a sense, by accident, because of selection against fear and aggression?

I didn't even consider that it would be anything except for direct selection. In any case, read the whole post for a run-down of the paper, but here's the blogger's conclusion:

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February 24, 2010

Face recognition is highly heritable

Filed under: Cognitive Science — Gene Expression @ 4:42 pm

Human face recognition ability is specific and highly heritable:

Compared with notable successes in the genetics of basic sensory transduction, progress on the genetics of higher level perception and cognition has been limited. We propose that investigating specific cognitive abilities with well-defined neural substrates, such as face recognition, may yield additional insights. In a twin study of face recognition, we found that the correlation of scores between monozygotic twins (0.70) was more than double the dizygotic twin correlation (0.29), evidence for a high genetic contribution to face recognition ability. Low correlations between face recognition scores and visual and verbal recognition scores indicate that both face recognition ability itself and its genetic basis are largely attributable to face-specific mechanisms. The present results therefore identify an unusual phenomenon: a highly specific cognitive ability that is highly heritable. Our results establish a clear genetic basis for face recognition, opening this intensively studied and socially advantageous cognitive trait to genetic investigation.

In other words, the strength of face recognition does not seem to track other intelligence test results much at all (including tests which measure verbal and visual memory). Rather, it seems to be a domain-specific competency, rather than emerging out of general intelligence. And, the variation in face recognition ability is highly heritable.

What's going on here? A reasonable guess for me is that the ability to recognize many, many, different faces isn't something that came up for most of human history. Even in a pre-modern village you'd see the same people over and over. By contrast, if you work in sales you probably need to juggle a lot of faces & names to be successful.

Remember that if a quantitative trait is highly heritable then by definition that means that directional selection wasn't operating to drive genes to fixation so that the population was monomorphic in trait value. In English that means if there was a huge benefit to being able to recognize hundreds of faces very well in the past, then we would be able to recognize hundreds of faces very well to the same extent. As it is the strongly for face recognition has to be more complex, with the direct selection applicable being some sort of balancing selection.

Citation: Jeremy B. Wilmer, Laura Germine, Christopher F. Chabris, Garga Chatterjee, Mark Williams, Eric Loken, Ken Nakayama, and Bradley Duchaine, Human face recognition ability is specific and highly heritable, doi:10.1073/pnas.0913053107

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February 20, 2010

The New York Times on Amy Bishop

Filed under: Cognitive Science — Gene Expression @ 12:20 pm

Covers all the major angles. Nice that there's a newspaper which can support this sort of reporting (on the other hand). Not surprising that Amy Bishop seems to have some history of delusions of grandeur, she's claiming that both she and her husband have an I.Q. of 180. That's 5.3 standard deviations above the mean. Assuming a normal distribution that's a 1 in 20 million probability. Of course the tails of the distribution are fatter beyond 2 standard deviations than expectation for I.Q., but at these really high levels (above 160) I'm skeptical that most tests are measuring anything real.

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