https://www.newyorker.com/magazine/2021/09/13/can-progressives-be-convinced-that-genetics-matters
September 13, 2021 Issue -- (There is also an audio link that I found useful)
"Can Progressives Be Convinced That Genetics Matters?
The behavior geneticist Kathryn Paige Harden is waging a two-front campaign: on her left are those who assume that genes are irrelevant, on her right those who insist that theyâre everything.
By Gideon Lewis-Kraus September 6, 2021 Kathryn Paige Harden.
âBuilding a commitment to egalitarianism on our genetic uniformity is building a house on sand,â - Harden.
Until she was thirty-three, Kathryn Paige Harden, a professor of psychology at the University of Texas at Austin, had enjoyed a vocational ascent so steady that it seemed guided by the hand of predestination. When she first went on the job market, at twenty-six, her graduate-school mentor, Eric Turkheimer, a professor at the University of Virginia, recommended her with an almost mystified alacrity. âMore than anyone else who has come through my lab, I find myself answering questions by saying, âWe should check with Paige,â â he wrote. âI am absolutely confident she will be a successful addition to any faculty, and she brings a significant chance of being a superstar.â Her early scholarship was singled out for prestigious awards and grants, and she was offered tenure at thirty-two. In 2016, she began co-hosting an Introduction to Psychology class from a soundstage, in the style of a morning showâshe and her colleague drank coffee from matching mugsâthat was live-streamed each semester to more than a thousand students. She couldnât cross campus without being stopped for selfies.
Harden works in the field of behavior genetics, which investigates the influence of genes on character traits (neuroticism, agreeableness) and life outcomes (educational attainment, income, criminality). Such research has historically relied upon âtwin studies,â which compare identical twins with fraternal ones to differentiate genetic from environmental effects. As a new professor, she co-founded the Texas Twin Project, the first registry engineered to maximize representation of low-income families from ethnically diverse backgrounds. In a recent paper, Harden asked, âYou only have one life to live, but if you rewound the tape and started anew from the exact same genetic and environmental starting point, how differently could your life go?â She continued, âOverall, twin research suggests that, in your alternate life, you might not have gotten divorced, you might have made more money, you might be more extraverted or organizedâbut you are unlikely to be substantially different in your cognitive ability, education, or mental disease.â In the past few years, Harden noted, new molecular techniques have begun to shore up the basic finding that our personal trajectories owe a considerable debt to our genes.
On sabbatical for the 2015-16 academic year, Harden and Elliot Tucker-Drob, a colleague to whom she was married at the time, were invited to New York City with their two young childrenâa three-year-old boy and a nine-month-old girlâas visiting scholars-in-residence at the Russell Sage Foundation. Russell Sage, which occupies a handsome Philip Johnson building in Manhattan, primarily supports sociologists, journalists, and economists, but it had recently launched an initiative to integrate the biological sciences. Harden felt almost immediately unwelcome at the regular fellowsâ lunches. Many of the left-leaning social scientists seemed certain that behavior-genetics research, no matter how well intentioned, was likely to lead us down the garden path to eugenics. The world would be better, Harden was told, if she quit. When their cohort went to see âHamilton,â the others professed surprise that Harden and Tucker-Drob had enjoyed it, as if their work could be done only by people uncomfortable with an inclusive vision of American history.
Harden assumed that such leeriness was the vestige of a bygone era, when genes were described as the âhard-wiringâ of individual fate, and that her critics might be reassured by updated information. Two weeks before her family was due to return to Texas, she e-mailed the fellows a new study, in Psychological Science, led by Daniel Belsky, at Duke. The paper drew upon a major international collaboration that had identified sites on the genome that evinced a statistically significant correlation with educational attainment; Belsky and his colleagues used that data to compile a âpolygenic scoreââa weighted sum of an individualâs relevant genetic variantsâthat could partly explain population variance in reading ability and years of schooling. His study sampled New Zealanders of northern-European descent and was carefully controlled for childhood socioeconomic status. âHope that you find this interesting food for thought,â she wrote.
William Darity, a professor of public policy at Duke and perhaps the countryâs leading scholar on the economics of racial inequality, answered curtly, starting a long chain of replies. Given the difficulties of distinguishing between genetic and environmental effects on social outcomes, he wrote, such investigations were at best futile: âThere will be no reason to pursue these types of research programs at all, and they can be rendered to the same location as Holocaust denial research.â By the time he wrote again, several hours later, one of Hardenâs few supporters among the fellows had changed the threadâs subject line from ânew genetics paperâ to âSeriously? Holocaust deniers?â Darity responded, âI feel just as strongly that we should not keep the notions that the world is 6000 years old or that climate change is a fabrication under consideration.â
Harden remarked that being called a climate skeptic was marginally preferable to being called a Holocaust denier. She offered to host a lunch to discuss the uncontroversial basics of genetics research for anyone interested. Darity was reluctant to let the matter go: âOne final comment from me, and then I will withdraw into my pique.â In 1994, he wrote, the political scientist Charles Murray and the late psychologist Richard Herrnstein âpublished a bestseller that achieved great notoriety, The Bell Curve. Apart from its claims about a genetic basis for a âracialâ hierarchy in intelligence, the book claimed that social outcomes like poverty and inequality in earnings had a genetic foundation. Personally, I thought the book was outrageous and a saddening resuscitation of ideas that had increasingly been dismissed as âpseudoscience.â Belskyâs work strikes me as an extension of the Murray-Herrnstein view of the world.â He concluded, âAt some point, I think we need to say enough is enough.â (Darity told me, of his e-mails, âI stand by all that.â)
An admirer of Darityâs workâespecially on reparations for slaveryâHarden was surprised that sheâd elicited such rancor from someone with whom she was otherwise in near-total political agreement. In the wake of the exchange, some of the other fellows stopped speaking to Harden, and the e-mail chain was forwarded to members of the foundationâs board. The next year, after winning the American Psychological Associationâs Distinguished Scientific Award for an Early Career Contribution to Psychology, Harden applied for a grant from Russell Sageâs biosciences initiative, which had supported similar research in the past. She received enthusiastic peer reviews from its scientific advisers, and was given to understand that the grantâs disbursal was a fait accompli. During a contentious meeting, however, the full board voted to overturn the scientific panelâs recommendation. Over the next year, a biosciences working group revised the programâs funding guidelines, stipulating in the final draft that it would not support any research into the first-order effects of genes on behavior or social outcomes. In the end, the board chose to disband the initiative entirely. (A spokesperson for Russell Sage told me by e-mail that the decision was based on the âconsideration of numerous factors, including RSFâs relative lack of expertise in this area.â)
Harden has spent the last five years thinking about Darityâs objections. As she put it to me recently, âWhen I reread his e-mails, it all struck me as very Chekhovian. Like, here are all the guns that are going to go off in Act V.â Harden understands why the left, with which she identifies, has nurtured an aversion to genetics. She went to graduate school in Charlottesville, the birthplace of Carrie Buck, a âfeeble-mindedâ woman who was sterilized against her will, in 1927, under a state eugenics program sanctioned by the Supreme Court. But she does not believe that a recognition of this horrifying history ought to entail the peremptory rejection of the current scientific consensus. The leftâs decision to withdraw from conversations about genetics and social outcomes leaves a vacuum that the right has gaily filled. The situation has been exploited as a âred pillâ to expose liberal hypocrisy. Today, Harden is at the forefront of an inchoate movement, sometimes referred to as the âhereditarian left,â dedicated to the development of a new moral framework for talking about genetics.
This fall, Princeton University Press will publish Hardenâs book, âThe Genetic Lottery: Why DNA Matters for Social Equality,â which attempts to reconcile the findings of her field with her commitments to social justice. As she writes, âYes, the genetic differences between any two people are tiny when compared to the long stretches of DNA coiled in every human cell. But these differences loom large when trying to understand why, for example, one child has autism and another doesnât; why one is deaf and another hearing; andâas I will describe in this bookâwhy one child will struggle with school and another will not. Genetic differences between us matter for our lives. They cause differences in things we care about. Building a commitment to egalitarianism on our genetic uniformity is building a house on sand.â
Harden understands herself to be waging a two-front campaign. On her left are those inclined to insist that genes donât really matter; on her right are those who suspect that genes are, in fact, the only things that matter. The history of behavior genetics is the story of each generationâs attempt to chart a middle course. When the discipline first began to coalesce, in the early nineteen-sixties, the memory of Nazi atrocities rendered the eugenics threat distinctly untheoretical. The reigning model of human development, which seemed to accord with postwar liberal principles, was behaviorism, with its hope that environmental manipulation could produce any desired outcome. It did not take much, however, to notice that there is considerable variance in the distribution of human abilities. The early behavior geneticists started with the premise that our nature is neither perfectly fixed nor perfectly plastic, and that this was a good thing. They conscripted as their intellectual patriarch the Russian Ă©migrĂ© Theodosius Dobzhansky, an evolutionary biologist who was committed to anti-racism and to the conviction that âgenetic diversity is mankindâs most precious resource, not a regrettable deviation from an ideal state of monotonous sameness.â
The fieldâs modern pioneers were keen to establish that their interest lay in academic questions, and they prioritized the comparatively clement study of animals. In 1965, John Paul Scott and John L. Fuller reported that, despite the discernible genetic differences among dog breeds, there did not seem to be categorical distinctions that might allow one to conclude that, say, German shepherds were smarter than Labradors. The most important variations occurred on an individual level, and environmental conditions were as important as innate qualities, if not more so.
This era of comity did not last long. In 1969, Arthur Jensen, a respected psychologist at Berkeley, published an article called âHow Much Can We Boost IQ and Scholastic Achievement?â in the Harvard Educational Review. Jensen coolly argued that there was an I.Q. gap between the races in America; that the reason for this gap was at least partly genetic, and thus, unfortunately, immutable; and that policy interventions were unlikely to thwart the natural hierarchy. The Jensen affair, which extended for more than a decade, prefigured the publication of âThe Bell Curveâ: endless public debate, student protests, burned effigies, death threats, accusations of intellectual totalitarianism. As Aaron Panofsky writes in âMisbehaving Science,â a history of the discipline, âControversies wax and wane, sometimes they emerge explosively, but they never really resolve and always threaten to reappear.â
The problem was that most of Jensenâs colleagues agreed with some of his basic claims: it did seem that there was something akin to âgeneral intelligenceâ in humans, that it could be meaningfully measured with I.Q. tests, and that genetic inheritance has a good deal to do with it. Critics quickly pointed out that the convoluted social pathways that led from genes to complex traits rendered any simple notion of genetic âcausationâ silly. In 1972, Christopher Jencks, a sociologist at Harvard, proposed the thought experiment of a country in which red-haired children were prevented from going to school. One might anticipate that such children would demonstrate a weaker reading ability, which, because red hair is genetic in origin, would be conspicuously linked to their genesâand would, in some bizarre sense, be âcausedâ by them.
Richard Lewontin, a geneticist and a staunch egalitarian, developed a different analogy. Imagine a bag of seed corn. If you plant one handful in nutrient-poor soil, and another in rich loam, there will be a stark difference in their average stalk height, irrespective of any genetic predisposition. (There will also be greater âinequalityâ among the well-provisioned plants; perhaps counterintuitively, the more uniformly beneficial the climate, the more pronounced the effects of genetic difference.) Jensenâs racial comparison was thus unwarranted and invidious: it was absurd to think, in the America of 1969, that different races enjoyed equally bountiful circumstances.
Behavior geneticists emphasized that their own studies showed that poorer children adopted by wealthy families saw substantial gains in average I.Q. This finding, it later emerged, obtained on a societal basis as well. The scholar James Flynn found that, for reasons that are not entirely understood, the average I.Q. of a population increases significantly over time: most people living a hundred years ago, were they given contemporary I.Q. tests, would easily have qualified as what early psychometricians called, with putative technical precision, âmoronsâ or âimbeciles.â Such tests might be measuring something real, but whatever it is cannot be considered âpurelyâ biological or inflexible.
Our ability to remediate genetic differences was thus a separate moral question. In 1979, the economist Arthur Goldberger published a mordant rejoinder to social conservatives who argued that genetic differences rendered the welfare apparatus supererogatory. âIn the same vein, if it were shown that a large proportion of the variance in eyesight were due to genetic causes, then the Royal Commission on the Distribution of Eyeglasses might well pack up,â he wrote. Just because outcomes might be partly genetic didnât mean that they were inevitable.
As twin studies proliferated throughout the nineteen-eighties, their results contributed to substantial changes in our moral intuitions. When schizophrenia and autism, for example, turned out to be largely heritable, we no longer blamed these disorders on cold or inept mothers. But, for such freighted traits as intelligence, liberals remained understandably anxious and continued to insist that differencesânot just on a group level but on an individual oneâwere merely artifacts of an unequal environment. Conservatives pointed out that an Ă -la-carte approach to scientific findings was intellectually incoherent.
In 1997, Turkheimer, perhaps the preĂ«minent behavior geneticist of his generation, published a short political meditation called âThe Search for a Psychometric Left,â in which he called upon his fellow-liberals to accept that they had nothing to fear from genes. He proposed that âa psychometric left would recognize that human ability, individual differences in human ability, measures of human ability, and genetic influences on human ability are all real but profoundly complex, too complex for the imposition of biogenetic or political schemata. It would assert that the most important difference between the races is racism, with its origins in the horrific institution of slavery only a very few generations ago. Opposition to determinism, reductionism and racism, in their extreme or moderate forms, need not depend on blanket rejection of undeniable if easily misinterpreted facts like heritability.â He concluded, âIndeed it had better not, because if it does the eventual victory of the psychometric right is assured.â
Having endured the summer of 2020 trapped indoors in the oppressive Austin heat, Harden was grateful for an invitation to spend this past June at Montana State University, in Bozeman. A recent influx of out-of-town wealth had accelerated during the pandemic, and the townâs industrial fixtures had been ruthlessly spruced up to suit the needs of remote knowledge workers. Harden, who has moss-colored eyes, a wry smile, and an earnest nonchalance, met me at a coffee shop that looked as though it had been airlifted that morning from San Francisco. She wore a soft flannel shirt, faded stone-washed jeans, and dark Ray-Ban sunglasses. The air was hot and dry, but Harden is the sort of person who seems accompanied by a perpetual breeze. â âThe Bell Curveâ came out when I was twelve years old, and somehow thatâs still what people are talking about,â she said. âThereâs a new white dude in every generation who gets famous talking about this.â Virtually every time Harden gives a presentation, someone asks about âGattaca,â the 1997 movie about a dystopia structured by genetic caste. Harden responds that the life of a behavior geneticist resembles a different nineties classic: âGroundhog Day.â
Harden was raised in a conservative environment, and though she later rejected much of her upbringing, she has maintained a convertâs distrust of orthodoxy. Her fatherâs family were farmers and pipeline workers in Texas, and her grandparentsâPentecostalists who embraced faith healing and speaking in tonguesâwere lifted out of extreme poverty by the military. âIt was the classic tale of the governmentâs deliberate creation of a white middle class,â she said. Her father served as a Navy pilot, then took a job flying for FedEx, and Harden and her brother grew up in an exurb of Memphis. Harden scandalized her Christian high school when, at fifteen, she wrote a term paper about âThe Bell Jar.â She has not recapitulated the arc of her parentsâ lives. âTheyâre still very religiousâvery suspicious of the mainstream media, secular universities, secular anything, which has accelerated in the Trump years.â
Hardenâs parents insisted that she stay in the South for college, and Furman University, a formerly Baptist college in South Carolina, gave her a full scholarship based on her near-perfect SAT scores. She received paid summer fellowships in rodent genetics, and found that she preferred the grunt work of the lab bench to the difficult multitasking required by the jobs in waitressing and retail to which she was accustomed. She only later realized that the point of the program was to draw students from underrepresented backgrounds into science. At twenty, she applied to graduate school in clinical psychology. Her fatherâs only comment was âI was afraid you were going to say that.â She was rejected almost everywhere, but Turkheimer, noting her lab experience and her exceptionally high quantitative G.R.E. scores, invited her for an interview. She wore a new Ann Taylor suit and he wore Tevas. Turkheimerâs e-mail avatar is the Greek letter psi, for âpsychology,â set against the Grateful Dead logo; he offered her admission on the condition that she stop calling him âsir.â
Her experiences as an apprentice scientist were only part of the reason that she grew disillusioned with evangelicalism: âThere was this incredible post-9/11 nationalismâflags on the altar next to crossesâthat infected my church to a point that felt immoral and gross. Sometimes I feel like I sat through eleven years of Christian school and absorbed all the things they didnât intend for me to absorb. I thought we were following a social-justice ethos in which the meek shall inherit the earth, and I mustâve missed the track that was the run-up to the Iraq War.â Turkheimer recommended a local psychoanalyst, who, Harden said, took her on as a âcharity case.â
It might have seemed peculiar that a behavior geneticist was recommending analytic treatment, but Turkheimer had long been known for his belief that biological explanations for behavior were unlikely ever to supplant cultural and psychological ones. Turkheimerâs longtime rival, the prolific researcher Robert Plomin, believed otherwise, predicting that we would one day achieve molecular-level purchase on what makes people who they are. Turkheimer associated himself with what Plomin lamented as âthe gloomy prospectââthe notion that the relevant processes were too messy and idiosyncratic to be fixed under glass. The prospect was gloomy, Turkheimer said, only from the perspective of a social scientist. As a person, he had a more sanguine view: âIn the long run, the gloomy prospect always wins, and no one would want to live in a world where it did not.â
This did not mean that behavior genetics was useless, only that it required a modest perspective on what could be achieved: twin studies might never explain how a given genotype made someone more likely to be depressed, but they could help avoid the kind of mistaken inference that blamed bad parenting. Hardenâs work in Turkheimerâs lab remained squarely within this tradition. For example, the state of Texas spent a lot of money on school programs to promote sexual abstinence, on the basis of research that showed a correlation between adolescent sexuality and subsequent antisocial behavior. Harden used a twin study to demonstrate that a twin who began having sex early showed no greater likelihood of engaging in risky behavior than her twin who had abstained. In other words, both behaviors might be the expression of some underlying predisposition, but no causal arrow could be drawn. She did similar work to show that the idea of âpeer pressureâ as a driver of adolescent substance abuse was, at best, a radical oversimplification of an extremely complex transactional dynamic between genes and environment.
Hardenâs years in graduate school coincided with the arrival of actual geneticists in a field long dominated by psychologists. In 2003, scientists completed the first full map of the human genome, and it seemed as though Plominâs vision would be borne out. Some illnessesâHuntingtonâs, for exampleâturned out to be the result of a mutation in a single gene, and there was a widespread assumption that complex personality traits might be as cleanly derived. A gene was purportedly identified for aggression, and one for depression, and one for homosexuality. But these studies couldnât be replicated, and the âcandidate geneâ era had to be written off as a gross misstep. It became clear that complex traits were governed by multiple genes, and that individual genes could pertain to a variety of attributes.
Around the time that Harden was finishing her dissertation, however, researchers began to wonder if it might be possible to identify hundreds or even thousands of places in the genome where differences in our DNA sequences could be correlated with a trait or an outcome. This research design was called a âgenome-wide association study,â or GWAS (pronounced ji-wass). Turkheimer was characteristically unimpressed with the initial results, which were weak. At the annual conference of the Behavior Genetics Association in 2013, he delivered a withering keynote address: trying to understand human behavior with a GWAS was like putting a CD under a microscope to figure out if a song was good. Harden, too, was sure that they would not learn anything from these contrived statistical exercises. âBut we were wrong,â she said.
In the last five years, GWAS results have rapidly evolved. Polygenic scores can now account for a good deal of a populationâs variance in height and weight, and have been shown to predict cardiovascular disease and diabetes. âThis is really a cause for celebration,â Plomin told me. âImagine the advent of predictive medicineâto be able to identify medical issues before they occur.â Researchers have also found links with complex behavioral traits. âSignificant hits have been reported for traits such as coffee and tea consumption, chronic sleep disturbances (insomnia), tiredness, and even whether an individual is a morning person or a night person,â Plomin notes, in his 2018 book, âBlueprint: How DNA Makes Us Who We Are.â The new research, he writes, âsignals the start of the DNA revolution in psychology.â
The largest GWAS for educational attainment to date found almost thirteen hundred sites on the genome that are correlated with success in school. Though each might have an infinitesimally small statistical relationship with the outcome, together they can be summed to produce a score that has predictive validity: those in the group with the highest scores were approximately five times more likely to graduate from college than those with the lowest scoresâabout as accurate a predictor as traditional social-science variables like parental income. Nobody knows quite what to do with these results, but, as one population geneticist put it to me, âthe train has left the stationâeven if researchers donât fully understand what theyâre learning, this is how the genome is used now.â
Harden and her collaborators currently conduct their own GWAS efforts; most recently, they have investigated behaviors including adolescent aggression and risktaking, which are strongly predictive of life span and labor-market outcomes. She knows that she may never convince Turkheimer, who continues to argue that the light these studies generate is too faint to dispel his gloom. But she thinks that they represent an incremental step forward: âEric says itâs dangerous to talk about genes if you donât know exactly how theyâre associated with the outcome, but we donât even really know how, exactly, poverty changes thingsâwhy is it good to be adopted into a rich family?â She added, âItâs impossible for me not to care about how what people start with shapes their lives.â
Harden was joined in Bozeman by her younger brother, Micah, who was visiting from Memphis. We sat together on the covered patio of the airy house Harden had rented with her boyfriend, an architectural designer named Travis Avery. It was the longest spell she had ever spent away from her children, who were on a road trip with Tucker-Drob. (The couple got divorced in 2018.) Micah had not yet read his sisterâs book but had grudgingly agreed to be genotyped for it. âWe have the same brown hair, same green eyes, same tendency to do what our stepmother refers to as the âHarden slow-blink,â closing our eyes for a few seconds when we are annoyed at someone,â she writes. âDespite these similarities, our lives have turned out differently.â Micah still lives near their childhood home, has not left the church, and can run up and down a soccer field âwithout gasping for oxygen.â Her broader point, she told me, was that siblings, who share only about half their DNA, are as unalike as they are similar. She said, âOn our thirteenth chromosome weâre basically two strangers.â
Micah had come with his wife, Steffi, and their ten-month-old, Hadley, a bright, sly child with an endearingly defiant stare. As the adults sat around talking, Hadley plotted to make off with the ramekins of almonds and glasses of wine. Each time she evaded adult supervision and vaulted onto the coffee table, Micah took the opportunity to troll his sister, saying delightedly, âLooks like Hadley won the genetic lottery!â Harden rolled her eyes and reminded him that this was the opposite of what sheâd meant. Micah, as it turned out, knew precisely what she meant; he had already described the book to Steffi as âtelling the right that they didnât bootstrap and telling the left that interventions are more complicated than they want to believe,â which Harden conceded was not a terrible prĂ©cis. Micah and Steffi had met playing soccer, and Harden teased them that Hadley might forsake the pitch for musical theatre. She thinks that all the books about the minor decisions of parentingâwhether to introduce carrots or broccoli first, sayâare âan attempt to psychologically defend ourselves from how little control we have in the world, about ourselves and our children.â
The episode at Russell Sage had prompted Harden to think about what her research really meant: âThe experience was a pivot point for me, away from a career that was almost entirely about the production of empirical research and toward doing more metascience.â âThe Genetic Lotteryâ reflects her years spent wandering in the desert. The book does not shy away from technical details, but it wears its learning lightly; alongside Hardenâs frequent Biblical allusions are references to the movies âCluelessâ and âSliding Doors.â
Harden described her book to me as âfundamentally defensive in a lot of ways,â and before she makes any claims for what we can learn from GWAS results she goes into great detail about their limitations. GWAS simply provides a picture of how genes are correlated with success, or mental health, or criminality, for particular populations in a particular society at a particular time: it wouldnât make sense to compare findings for educational attainment for women in America today with women who came of age before sex-based discrimination was outlawed in higher education. And GWAS results are not âportableâ: a study conducted on white Britons tells you little about people in Estonia or Nigeria. Polygenic scores remain poor predictors of individual outcomesâthere are plenty of people on the low end of the spectrum for educational attainment who go on to graduate studies, and plenty of people on the high end who never secure a high-school diploma.
GWAS results can accidentally reveal as much about culture or geography as they do about genes. A study of chopstick use in San Francisco would find that proficiency is genetically correlated with East Asian ancestry, which is a far cry from the discovery of an inborn dexterity with a particular utensil. One way to sidestep this pitfall is by comparing GWAS results within families, where they have been shown to reliably account for differences in life outcomes among siblings. But even this measure does not solve Christopher Jencksâs redhead problem. âA person might go far in education because they are smart and curious and hard-working, or because they are conforming and risk-averse and obsessive, or because they have features (pretty, tall, skinny, light-colored) that privilege them in an intractably biased society,â Harden writes. âA study of what is correlated with succeeding in an education system doesnât tell you whether that system is good, or fair, or just.â
At some point, Harden has to set aside her caveats and assert that sheer genetic luck plays a causal role in outcomes that matter: âIf people are born with different genes, if the genetic Powerball lands on a different polygenic combination, then they differ not just in their height but also in their wealth.â For her, accepting this is the necessary prelude to any conversation about what to do about it. âIf you want to help people, you have to know whatâs most effective, so you need the science,â she told me. Harden thinks that the conversation about behavior genetics will continue to go in circles as long as we preserve the facile distinction between immutable genetic causes and malleable environmental ones. We would be better off if we accepted that everything is woven of long causal chains from genes through culture to personhood, and that the more we understand about them the more effective our interventions might be.
The first thing that social-science genomics can do is help researchers control for confounding genetic variables that are almost universally overlooked. As Harden puts it in her book, âGenetic data gets one source of human differences out of the way, so that the environment is easier to see.â For example, beginning in 2002, the federal government spent almost a billion dollars on something called the Healthy Marriage Initiative, which sought to reduce marital conflict as a way of combatting poverty and juvenile crime. Harden was not surprised to hear that the policy had no discernible effect. Her own research showed that, when identical-twin sisters have marriages with different levels of conflict, their children have equal risk for delinquency. The point was not to estimate the effects of DNA per se, but to provide an additional counterfactual for analysis: would an observed result continue to hold up if the people involved had different genes? Harden can identify studies on a vast array of topicsâWill coaching underresourced parents to speak more to their children reduce educational gaps? Does having dinner earlier improve familial relationships?âwhose conclusions she considers dubious because the researchers controlled for everything except the fact that parents pass along to their children both a home environment and a genome.
She acknowledged that gwas techniques are too new, and the anxieties about behavior genetics too deeply entrenched, to have produced many immediately instrumental examples so far. But she pointed to a study from last year as proof of concept. A team of researchers led by Jasmin Wertz, at Duke, used GWAS results to examine four different âaspects of parenting that have previously been shown to predict childrenâs educational attainment: cognitive stimulation; warmth and sensitivity; household chaos (reverse-coded to indicate low household chaos); and the safety and tidiness of the family home.â They found that one of themâcognitive stimulationâwas linked to childrenâs academic achievement and their mothersâ genes, even when the children did not inherit the relevant variants. Parental choices to read books, do puzzles, and visit museums might be conditioned by their own genes, but they nevertheless produced significant environmental effects.
Even the discovery that a particular outcome is largely genetic doesnât mean that its effects will invariably persist. In 1972, the U.K. government raised the age at which students could leave school, from fifteen to sixteen. In 2018, a research group studied the effects of the extra year on the students as adults, and found that their health outcomes for measures like body-mass index, for whatever reason, improved slightly on average. But those with a high genetic propensity for obesity benefitted dramaticallyâa differential impact that might easily have gone unnoticed.
Some of Hardenâs most recent research has looked at curricular tracking for mathematics, an intuitive instance of how gene-environment interactions can create feedback loops. Poor schools, Harden has found, tend to let down all their students: those with innate math ability are rarely encouraged to pursue advanced classes, and those who struggle are allowed to drop the subject entirelyâa situation that often forecloses the possibility of college. The most well-off schools are able to initiate virtuous cycles in the most gifted math students, and break vicious cycles in the less gifted, raising the ceiling and the floor for achievement.
Harden has perceived, in the wake of studies like these, a new willingness to consider the role of genetics: âI get e-mails now from curious social scientists that say, âIâve never thought genetics was useful or relevant for me, in part because I worried there was no way to talk about genes and intelligence, or genes and behavior, without dabbling in Murray-style scientific racism.â â
The Murray-Herrnstein gun that hung on the wall of William Darityâs e-mail went off about a year later. On April 23, 2017, the popular podcaster Sam Harris released an episodeââForbidden Knowledgeââdesigned to trigger a commotion among liberal intellectuals. Harris was affiliated with the so-called Intellectual Dark Web, a miscellaneous club (from which he has since distanced himself) bound together by a shared fixation with what it perceives to be liberal groupthink. In his interviews, Harris adopts a drowsy monotone that seems pitched to signal his commitment to the dispassionate promotion of disputatious ideas. On this occasion he invited listeners to âstrap inâ for a conversation with Charles Murray about âThe Bell Curve,â which Harris advertised as âone of the most controversial books in living memory.â
The book generated such outsized hostility, according to Harris, because it traffics in unpleasant truths. âPeople donât want to hear that intelligence is a real thing, and that some people have more of it than others,â he said. âThey donât want to hear that differences in I.Q. matter because theyâre highly predictive of differential success in lifeâand not just for things like educational attainment and wealth but for things like out-of-wedlock birth and mortality. People donât want to hear that a personâs intelligence is in large measure due to his or her genes and there seems to be very little we can do environmentally to increase a personâs intelligence, even in childhood. Itâs not that the environment doesnât matter, but genes appear to be fifty to eighty per cent of the story. People donât want to hear this. And they certainly donât want to hear that average I.Q. differs across races and ethnic groups.â
Harris was drawn to Murrayâs defense after an incident at Middlebury College, the previous month, in which Murray was shouted down by student protesters and his faculty chaperone was injured in a melee. Harris considered the deplatforming âpart of an anti-free-speech hysteria that is spreading on college campuses,â and concluded, âI find the dishonesty and hypocrisy and moral cowardice of Murrayâs critics shocking. And the fact that I was taken in by this defamation of him, and effectively became part of a silent mob that was just watching what amounted to a modern witch-burningâthat was intolerable to me.â The two men discussed Murrayâs contention that observed racial differences are at least partly genetic in origin, and that meliorist interventions like welfare and affirmative-action programs are unlikely to prove successful.
Harris seemed less interested in Murray as a scholar or pundit than as a culture-war trope. Soon after the events at Middlebury, the Web magazine Vox had published a piece that rejected even Murrayâs basic points about intelligence tout court. Harrisâs podcast seemed designed to reveal that the leftâs repudiation of Murray was motivated by politics rather than by science. After it was released, Vox asked Turkheimer to contribute a rebuttal, and he proposed that Harden collaborate. Harden felt a responsibility to accept the assignment. âPeople are very tempted by Murrayâs ideas, and thereâs a certain kind of person who almost certainly hasnât read âThe Bell Curveâ but listens to Sam Harris, who has a huge audience,â she told me.
She believed that the leftâs standard-issue response was unhelpful. âThis is a very Christian thing Iâm about to say, but it reminds me of the episode where Jesus is tempted by Satan in the desert,â she told me, in Bozeman. âThereâs just enough truth in Murray that if you say, âThis is all wrong,â you paint yourself into a corner where you say intellectually dishonest things. Jesus has to say, âThis part is true, and this part is false.â â She stopped herself. âDonât write that Iâm comparing Murray to Satan,â she said, and then continued, âI know we all want to say itâs not true that âintelligence tests predict things,â but thatâs not the lie.â To say that sort of thing ran the risk of furthering the martyrology of Murray, and of lending lustre to the notion that his ideas were indeed âforbidden knowledge.â The scholar and critic Fredrik deBoer, who has drawn heavily on Hardenâs work, has been even more pointed in his criticism. In a 2017 essay, he wrote, âLiberals have flattered themselves, since the election, as the party of facts, truth tellers who are laboring against those who have rejected reason itself. And, on certain issues, I suspect they are right. But letâs be clear: the denial of the impact of genetics on human academic outcomes is fake news.â
The Vox piece, which Harden and Turkheimer wrote with the social psychologist Richard Nisbett, was headlined âCharles Murray is once again peddling junk science about race and IQ.â There is a lot of good evidence, they wrote, to support the ideas that âintelligence, as measured by IQ tests, is a meaningful constructâ and that âindividual differences in intelligence are moderately heritable.â They even conceded, with many qualifications, that âracial groups differ in their mean scores on IQ tests.â But there was simply no good scientific reason to conclude that observed racial gaps were anything but the fallout from the effects of racism. They pointed out that in the one instance when Harris used James Flynnâs work to push back against Murrayâs ideas, Murray responded with some hand-waving about a research paper that he admitted was too complicated for him to understand.
Despite its inflammatory headline, the article represented an unusually subtle culture-war intervention. Nevertheless, Harris and his legion of supporters took it as the instigation of a âsmear campaign.â In Quillette, the researcher Richard Haier compared Harden and Turkheimerâs repudiation of Murray to climate-change denialâthe second time in a year that Harden had been thus indicted, this time from the right. The recriminations of what Harden now describes as âthe Vox fiascoâ dragged on over the next year, with parades of arguments and counterarguments, leaked personal e-mails, and levels of sustained podcasting that were, by anyoneâs standards, extreme. Harden told me, âThe popular reaction was so divorced from that of the scientific community that men on the Internet were sending me papers to read without realizing they were citing work by my ex-husband, and that the work itself was a meta-analysis of my own papers.â
Last summer, an anonymous intermediary proposed to Harris and Harden that they address their unresolved issues. Harden appeared on Harrisâs podcast, and patiently explained why Murrayâs speculation was dangerously out in front of the science. At the moment, technical and methodological challenges, as well as the persistent effects of an unequal environment, would make it impossible to conduct an experiment to test Murrayâs idly incendiary hypotheses. She refused to grant that his provocations were innocent: âI donât disagree with you about insisting on intellectual honesty, but I think of it as âboth/andââI think that that value is very important, but I also find it very important to listen to people when they say, âIâm worried about how this idea might be used to harm me or my family or my neighborhood or my group.â â (Harris declined to comment on the record for this piece.) As she once put it in an essay, âThere is a middle ground between âletâs never talk about genes and pretend cognitive ability doesnât existâ and âletâs just ask some questions that pander to a virulent on-line community populated by racists with swastikas in their Twitter bios.â â
Harden is not alone in her drive to fulfill Turkheimerâs dream of a âpsychometric left.â Dalton Conley and Jason Fletcherâs book, âThe Genome Factor,â from 2017, outlines similar arguments, as does the sociologist Jeremy Freese. Last year, Fredrik deBoer published âThe Cult of Smart,â which argues that the education-reform movement has been trammelled by its willful ignorance of genetic variation. Views associated with the âhereditarian leftâ have also been articulated by the psychiatrist and essayist Scott Alexander and the philosopher Peter Singer. Singer told me, of Harden, âHer ethical arguments are ones that I have held for quite a long time. If you ignore these things that contribute to inequality, or pretend they donât exist, you make it more difficult to achieve the kind of society that you value.â He added, âThereâs a politically correct left thatâs still not open to these things.â Stuart Ritchie, an intelligence researcher, told me he thinks that Hardenâs book might create its own audience: âThereâs so much toxicity in this debate that itâll take a long time to change peopleâs minds on it, if at all, but I think Paigeâs book is just so clear in its explanation of the science.â
The nomenclature has given Harden pause, depending on the definition of âhereditarian,â which can connote more biodeterminist views, and the definition of âleftââdeBoer is a communist, Alexander leans libertarian, and Harden described herself to me as a âMatthew 25:40 empiricistâ (âThe King will reply, âTruly I tell you, whatever you did for one of the least of these brothers and sisters of mine, you did for meâ â). The political sensitivity of the subject has convinced many sympathetic economists, psychologists, and geneticists to keep their heads below the parapets of academia. As the population geneticist I spoke to put it to me, âGeneticists know how to talk about this stuff to each other, in part because we understand terms like âheritability,â which we use in technical ways that donât always fully overlap with their colloquial meanings, and in part because weâre charitable with each other, assume each otherâs good faithâwe know that our colleagues arenât eugenicists. But we have no idea how to talk about it in public, and, while I donât agree with everything she said, sometimes it feels like weâve all been sitting around waiting for a book like Paigeâs.â
Hardenâs outspokenness has generated significant blowback from the left. On Twitter, she has been caricatured as a kind of ditzy bourgeois dilettante who gives succor to the viciousness of the alt-right. This March, after she expressed support for standardized testingâwhich she argues predicts student success above and beyond G.P.A. and can help increase low-income and minority representationâa parody account appeared under the handle @EugenicInc, with the name âDr. Harden, Social Justice Through Eugenics!â and the bio âNot a determinist, but yes, genes cause everything. I just want to breed more Hilary Clintonâs for higher quality future people.â One tweet read, âIn This House We Believe, Science is Real, Womens Rights are Human Rights, Black Lives Matter, News Isnt Fake, Some Kids Have Dumb-Dumb Genes!!!â
In 2018, she wrote an Op-Ed in the Times, arguing that progressives should embrace the potential of genetics to inform education policy. Dorothy Roberts, a professor of law, sociology, and Africana studies at the University of Pennsylvania, strongly disagreed: âThereâs just no way that genetic testing is going to lead to a restructuring of society in a just way in the futureâwe have a hundred years of evidence for what happens when social outcomes are attributed to genetic differences, and it is always to stigmatize, control, and punish the people predicted to have socially devalued traits.â Darity, the economist, told me that he doesnât see how Harden can insist that differences within groups are genetic but that differences between them are not: âItâs a feint and a dodge for her to say, âWell, Iâm only looking at variations across individuals.â â
There is a good precedent for this kind of concern. In âBlueprint,â Robert Plomin wrote that polygenic scores should be understood as âfortune tellersâ that can âforetell our futures from birth.â Jared Taylor, a white-supremacist leader, argued that Plominâs book should âdestroy the basis for the entire egalitarian enterprise of the last 60 or so years.â He seized on Plominâs claim that, for many outcomes, âenvironmental levers for change are not within our grasp.â Taylor wrote, âThis is a devastating finding for the armies of academics and uplift artists who think every difference in outcome is societyâs fault.â He continued, âAnd, although Blueprint includes nothing about race, the implications for âracial justiceâ are just as colossal.â Harden has been merciless in her response to behavior geneticists whose disciplinary salesmanshipâand perhaps worseâinadvertently indulges the extreme right. In her own review of Plominâs book, she wrote, âInsisting that DNA matters is scientifically accurate; insisting that it is the only thing that matters is scientifically outlandish.â â(Plomin told me that Harden misrepresented his intent. He added, âGood luck to Paige in convincing people who are engaged in the culture wars about this middle path sheâs suggesting. . . . My view is it isnât worth confronting people and arguing with them.â)
With the first review of Hardenâs book, these dynamics played out on cue. Razib Khan, a conservative science blogger identified with the âhuman biodiversityâ movement, wrote that he admired her presentation of the science but was put off by the bookâs politics; though he notes that a colleague of his once heard Harden described as âCharles Murray in a skirt,â he clearly thinks the honorific was misplaced. âAlas, if you do not come to this work with Hardenâs commitment to social justice, much of the non-scientific content will strike you as misguided, gratuitous and at times even unfair.â This did not prevent some on the Twitter left from expressing immediate disgust. Kevin Bird, who describes himself in his Twitter bio as a âradical scientist,â tweeted, âPersonally, I wouldnât be very happy if a race science guy thought my book was good.â Harden sighed when she recounted the exchange: âItâs always from both flanks. It felt like another miniature version of Harris on one side and Darity on the other.â
The day after Hardenâs brother returned to Memphis, she and I went for a walk around the campus of Montana State University. We wandered into the Museum of the Rockies, which has a world-class collection of dinosaur fossils, and she remarked that the experience would have been more fun with her children. I asked if her work had given her any special insights into the challenges of parenting, and she laughed and threw up her hands, joking that the only established public roles for psychology professors were either as center-right pundits or as dispensers of child-rearing advice. She told me, âAs a parent, I try to keep in mind that differences between people are examples of runaway feedback loops of gene-by-environment interaction. People have some initial genetic predisposition to something, and that leads them to choose certain friends over other friends, and these initial exposures have a certain effect, and you like that effect and you choose it again, and then these feedback loops become self-reinforcing.â
Behavior geneticists frequently quote an old disciplinary chestnut about how first-time parents are naĂŻve behaviorists and that a second child turns them into convinced geneticists. In one chapter of her book, Harden mentions that her son struggles with a speech impairment. âLooking at how my children differ in their ability to articulate words, I can easily see the capricious hand of nature,â she writes. âWhen it comes to inheriting whatever combination of genetic variants allows one to pronounce a word like âsquirrelâ by the age of three, my daughter was lucky. My son was not.â She emphasizes that parents are already well aware of how we might talk about genetics without making normative judgments. âI certainly am not implying that one of my children is âsuperiorâ or âinferiorâ to the other one,â she writes. âVerbal ability is valued, but having strong verbal ability doesnât make one of my children more valuable to me. The genetic differences between them are meaningful for their lives, but those differences do not create a hierarchy of intrinsic worth.â
The ultimate claim of âThe Genetic Lotteryâ is an extraordinarily ambitious act of moral entrepreneurialism. Harden argues that an appreciation of the role of simple genetic luckâalongside all the other arbitrary lotteries of birthâwill make us, as a society, more inclined to ensure that everyone has the opportunity to enjoy lives of dignity and comfort. She writes, âI think we must dismantle the false distinction between âinequalities that society is responsible for addressingâ and âinequalities that are caused by differences in biology.â â She cites research showing that most people are much more willing to support redistributive policies if differences in opportunity are seen as arbitrarily unfairâand deeply pervasive.
As she put it to me in an e-mail, âEven if we eliminated all inequalities in educational outcomes between sexes, all inequalities by family socioeconomic status, all inequalities between different schools (which as you know are very confounded with inequalities by race), weâve only eliminated a bit more than a quarter of the inequalities in educational outcomes.â She directed me to a comprehensive World Bank data set, released in 2020, which showed that seventy-two per cent of inequality at the primary-school level in the U.S. is within demographic groups rather than between them. âCommon intuitions about the scale of inequality in our society, and our imaginations about how much progress we would make if we eliminated the visible inequalities by race and class, are profoundly wrong,â she wrote. âThe science confronts us with a form of inequality that would otherwise be easy to ignore.â