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Many people think of prejudice as primarily a right-wing phenomenon. Philosopher Mike Huemer argues instead that it’s found right across the political spectrum. In his view, many contemporary progressives display the same psychological tendencies associated with older forms of bigotry, just directed at different targets.

Below is a brief excerpt from an excellent Substack essay he recently published on the topic, titled “Progressive Intellectuals: Image vs. Reality.” If you enjoy it, be sure to check out the full essay - it’s well worth your time.

If you move in even moderately high-status circles in our society, you’re basically never going to run into right-wing bigots. But you’re going to be repeatedly bombarded by left-wing bigotry...
Some manifestations of this prejudice:
Collectivist obsession
Progressive intellectuals are obsessed with race, sex, and other “identity groups”, far more so than normal Americans... When two people have a conflict, the progressive “anti-racist” needs to know the races of the two people before he decides which side he is on. The “anti-sexist” feminist needs to know the genders of the two people.
Animosity
A classic feature of racism is animosity toward one or more particular races. In traditional, right-wing racism, that would be hatred toward blacks, Jews, Latinos, and perhaps Asians. Traditional sexism involves having lower respect for women (though perhaps not hatred).
In contemporary, left-wing racism, we see hatred toward white people, and perhaps Jews, and perhaps Asians. (The Jews get it from both sides.) In left-wing sexism, we see hatred and contempt for men.
Progressives don’t like to think of themselves as hate-mongers. But if someone talked about any other group the way progressives talk about white men—e.g., talking about the harms of “whiteness”; going on about wrongs committed by white men, emphasizing their race and sex, while passing over wrongs committed by other groups—progressives would take one nanosecond to label that “hate speech”.
Scapegoating
Progressives like to blame white people for most of the world’s problems. This is another classic feature of racism. Right-wing racists such as the Nazis tried to blame the Jews for most of society’s problems. It doesn’t cease to be racism just because you pick a different race to scapegoat.
Stereotyping
Another classic feature of racism: negative stereotyping. Traditional racists would stereotype Jews as greedy, blacks as criminals, etc. Traditional sexists stereotype women as less capable than men. Left-wing bigots, on the other hand, stereotype white men as abusers and oppressors, and other groups as victims of white males.
That is the first element of progressive self-deception: they style themselves warriors against prejudice, but they are the biggest force stoking prejudice in our society. They think that their prejudice is different because the group they’re attacking is actually bad. They don’t see their stereotypes as stereotypes but just as the truth. That, of course, is what all bigots think.

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Steve

The Ideological Turing Test, Moral Double Standards, and Homosexuality in Rats

Steve Stewart-Williams — Sat, 27 Jun 2026 10:02:41 GMT

Photo by Ana Claudia Quevedo Estrada on Pexels

Welcome to the June 2026 edition of the N³ Newsletter Linkfest: a collection of links to papers and articles that grabbed my attention over the last month. On the menu today…

Why you should be wary of people who want to be seen as highly moral
How GLP-1s affect dating and employment
Casual sex and self-esteem in men vs. women
Homosexuality in rats
The surprising connections between mental and physical health

Around half the items are free to read for everyone; the rest are for paid subscribers only. I tend to put my spicier content behind a paywall, so if you’ve got a high spice tolerance, consider becoming a paid subscriber.

You can access the complete collection of Linkfests here.

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How Many Senses Do We Have?

Most people would say five - but according to many neuroscientists, we have a lot more than that. Depending on how we slice the cake, we might have ten, or maybe 21, or maybe 33. [Link.]

GLP-1s and the Female Obesity Penalty

A new study suggests that weight loss can have effects far beyond health. Among women starting GLP-1s, single women were more likely to enter relationships, and unemployed women were more likely to find work. Women already in relationships or employment saw little change, suggesting that the “obesity penalty” operates largely through first impressions during the early stages of relationship formation or hiring. [Preprint; Link.]

Stacked matched event studies for women first starting a GLP-1 for weight loss. Controls are later adopters, observed before their own start, plus interested never-users, propensity-score reweighted within cohort × employment × partnership cells. Bars are 95 percent confidence intervals, clustered by person. Panel A shows GLP-1 impacts on BMI. Panels B–D use the quarterly household panel in half-year event periods, relative to the half-year before start, with stack-person and cohort-by-quarter fixed effects. Panel B (married or cohabiting) splits by baseline partnership. Panels C (employment) and D (weekly hours worked) split by baseline employment status. Source: Diamond (2026).

Evolutionary Mismatch in the Classroom: Boys Are More Mismatched Than Girls

Why do more boys than girls struggle in the classroom? Part of it may be mismatch between the demands of school and boys’ evolved nature. To start with, boys are, on average, more physically active than girls and less suited to prolonged sitting and verbal instruction. As a result, they’re more likely than girls to be flagged as having behavioral difficulties. On top of that, schools often fail to capitalize on boys’ relative cognitive strengths in spatial and mechanical reasoning. [Link.]

Are Free Speech Advocates Secret Racists?

Nope. Across multiple datasets from multiple nations, people who placed more value on free speech were more likely to hold racially tolerant attitudes. This is consistent with the idea that free speech and tolerance spring from the same broader liberal ethos. [Link.]

The Ideological Turing Test

Can you describe your political opponents’ views so well that they wouldn’t be able to tell whether you agree with them? If so, you’ve passed the “ideological Turing test,” an informal measure of how well you understand your opponents’ positions. According to new research, people who do better on this test - that is, people who understand their opponents’ views better - tend to be less hostile toward their opponents: They see them as less ignorant, less irrational, and less immoral. [Link.]

Do Men Earn More? If So, Which Ones?

Everyone’s heard the claim: Men earn more than women. According to recent data, however, the generalization isn’t quite right. A more accurate formulation would be that married men earn more than women, and also than single men. Single men, in contrast, earn no more than women. Is this because men knuckle down when they marry, or because women are more likely to marry high earning men? It seems to be largely the latter. [Link.]

Women in Academia Do Just as Well - Until They Become Mothers

Before they have children, women do roughly as well as men in academia. Afterwards, however, women fall behind. What explains this pattern? Candidate explanations include that academia discriminates against mothers rather than women in general (seems unlikely); that despite considerable efforts to improve things, the demands of an academic career are still hard to juggle with motherhood (could be part of it); and that women’s priorities change after having children (seems like a plausible contributor). [Link.]

The figure plots the gender-specific impacts of children across event time. Outcomes shown at event time t are relative to the year before the first childbirth t = −1. The figure includes 95% confidence intervals around the coefficients. The estimations include fixed effects for age, year, and years since PhD start relative to event. Source: Cairo et al. (2026).

Moral Double Standards

People who want the world to see them as highly moral are more likely to judge others harshly, while turning a blind eye to their own moral failings. [Link.]

Perceived wrongness of others’ transgressions (left panel) and self-reported frequency of own transgressions (right panel) as a function of moral character (as benevolence and universalism values) and reputation management motives (as power and achievement values) in study 1 (N = 34,323). Source: Dong et al. (2023).

Why Equal Societies Have Larger Sex Differences

Steve Stewart-Williams — Thu, 25 Jun 2026 09:02:01 GMT

You can now watch my recent appearance on the Art of It podcast with Neo McNulty. We had a fun, wide-ranging conversation about evolutionary psychology and my new book, A Billion Years of Sex Differences. Here are some of the many topics we covered:

What is evolutionary psychology?
The evolution of sex differences in humans and other animals
Human sex differences, ranked from largest to smallest
Why sex differences in our species are smaller than those in most other mammals
The evolution of romantic love
The manosphere
The Cinderella effect
Why “natural” doesn’t mean “good”

The episode is available on Spotify, on Apple Podcasts, and wherever else you get your podcasts. You can also watch it on Neo’s Art of It YouTube channel.

Buy A Billion Years!

Follow me on Twitter/X for more psychology, evolution, and science.

How You Can Support the Newsletter

If you like what I’m doing with The Nature-Nurture-Nietzsche Newsletter and would like to support my work, please consider upgrading to a paid subscription. A paid subscription gets you:

Full access to all new posts and the archive
Full access to exclusive content such as my “12 Things Everyone Should Know” posts, Linkfests, and other regular features
Full access to excerpts from my book A Billion Years of Sex Differences
The ability to post comments and engage with me and the N³ Newsletter community

Paid subscriptions help support my efforts to explore controversial and important topics, and give me the freedom to follow the evidence wherever it leads.

Thanks!

Steve

Misinformation in Intro Psych Textbooks

Steve Stewart-Williams — Tue, 23 Jun 2026 10:01:24 GMT

Photo by Nijwam Swargiary on Unsplash

In Case You Missed It…

Introductory psychology textbooks still haven’t caught up with the science. Despite years of criticism, they continue to promote debunked research, to present psychology as more settled than it is, and to be overly credulous of ideas that buttress progressive political pieties.

Among other things, many intro psych textbooks gloss over flaws in famous studies such as the Stanford Prison Experiment; misrepresent areas like evolutionary psychology; present highly contested but left-friendly ideas like stereotype threat as settled science; promote psychological myths such as that violent video games cause real-world violence; and ignore exaggerations and distortions in famous case studies like that of Phineas Gage and Kitty Genovese.

The relative frequencies of these and other errors are shown in the table below.

The table comes from a recent paper by Jeffrey Brown and Christopher Ferguson. Here’s the abstract:

Recent scholarship has identified that factual errors have been common in introductory psychology textbooks. These errors tend to be in the direction of making psychological research appear more consistent than it is, as well as promoting viewpoints consistent with politically progressive ideologies. Some famous experiments in psychology have also seen serious questions raised about their validity. Given that these conversations have gone on for about a decade, it is worth considering whether identification of these issues resulted in improved coverage in introductory textbooks. Textbooks were sampled at two time points. Sixteen textbooks were sampled in 2018, and 18 in 2023. Although some improvements are seen from earlier studies, results indicated that errors in textbooks have remained common even after this issue had been clearly identified in the published literature. Misreporting of basic scientific information remains common in introductory textbooks, despite improvements in some areas. Textbook authors should be alert to potential misinformation, particularly related to controversial topics. Introductory psychology teachers may need to be aware that not all information presented in textbooks is true.

You can access the Brown and Ferguson paper here, or request a free copy from the authors here.

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Steve Stewart-Williams

We Can't Just Lie About Sex Differences

Steve Stewart-Williams — Sat, 20 Jun 2026 10:01:35 GMT

In Case You Missed It…

I recently sat down with Nikil Mukerji and Timur Sevincer of the German skeptic group GWUP to discuss evolutionary psychology, nature and nurture, and my new book, A Billion Years of Sex Differences. The interview appeared in Skeptiker magazine last week, but Nikil and Timur kindly agreed to let me reproduce it here.

Before we get to that, though, a quick request. This article is free to read for everyone. If you enjoy it and would like access to all Nature-Nurture-Nietzsche content, please consider becoming a paid subscriber.

A paid subscription gives you:

Full access to all new posts and the archive
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Paid subscriptions also help support my efforts to explore important and controversial topics, and give me the financial freedom to follow the evidence wherever it leads without fear of cancellation.

Thank you - and now, on with the interview.

In this conversation with Timur Sevincer and Nikil Mukerji, Steve Stewart-Williams discusses what evolutionary psychology actually claims, how the field can deepen our understanding of human nature, where the field has gone wrong, why the charge of pseudoscience misses the target, and how skeptics should respond when real science becomes politically unwelcome.

Common Misunderstandings About Evolutionary Psychology

Timur Sevincer: As skeptics, we care about pseudoscience, but also about exaggerated, distorted, or plainly false scientific claims. Which claims about sex differences or evolutionary psychology are most often misrepresented?

Steve Stewart-Williams: The list is long! A common view is that evolutionary psychology is a way to justify existing social roles, especially traditional sex roles. Another is that it’s a way to excuse misbehaviour, especially male misbehaviour. I think both claims are false.

Explaining a behaviour is not the same as morally justifying it. To think otherwise is to commit the naturalistic fallacy – the mistaken assumption that what’s natural is therefore morally right. We have to decide for ourselves what’s right and wrong. We shouldn’t let natural selection dictate our ethics. Evolution can explain behaviour without excusing it.

Another common claim is that evolutionary hypotheses are unfalsifiable. I don’t think that’s true either. Evolutionary hypotheses are falsifiable,1 and many have been falsified. More of my own hypotheses than I’d care to admit have been falsified. I’ve come up with a hypothesis, done the research, and then the world has said: no, you’re wrong about that.

A further misunderstanding is that evolutionary psychologists think men and women are almost different species: women are monogamous, men are promiscuous; women are choosy, men will sleep with anything that moves; men care only about a woman’s looks, women only about a man’s resources. None of this is what evolutionary psychologists say. Most human sex differences are statistical differences with large overlap. Both sexes can form committed relationships and both can be interested in casual sex. Both sexes are choosy about long-term partners and both care about looks.

Finally, many people assume that if a trait has an evolutionary component, it must therefore be fixed or biologically predetermined. But that’s not the claim. Genes may push development in certain directions, but they’re not the only influences. Learning, culture, incentives, and institutions also matter. The claim is not that biology alone is destiny. The claim is that biology is part of the causal story, albeit an important part.

Timur Sevincer: I teach open-minded, curious, and intelligent students. However, some of these misunderstandings seem to be very common before they engage with evolutionary psychology in more depth. In rare cases, some course evaluation comments continue to portray evolutionary psychology as pseudoscience even after extensive discussion of overwhelming empirical evidence. Those ideas must come from somewhere.

Steve Stewart-Williams: Yes. I’ve encountered that too, though less in Malaysia, where I now teach, than in the UK. Some people appear to associate evolutionary psychology with outdated or harmful ideas before they’ve really looked at the evidence. They’ve picked up widespread but mistaken views about the field. I think there’s been a successful misinformation campaign against it.

For many people, though, it’s possible to persuade them that, even if some evolutionary psychological ideas turn out to be wrong, the motivation isn’t bad. Evolutionary psychologists are not trying to drag the world backwards.

Is Evolutionary Psychology Pseudoscience?

Nikil Mukerji: Do you have a specific concept of pseudoscience in mind? I ask because this is one of my own areas of work.

Steve Stewart-Williams: In that case, I’ll say no and ask you for your definition!

Nikil Mukerji: Pseudoscience is not simply unfalsifiability. Some pseudosciences, such as homeopathy, are eminently falsifiable and have been falsified. The core issue is that they fake doing science.

Frankfurt describes bullshit as indifference to truth.2 I think one can extend this idea. Every practice has constitutive norms. Science is governed by truth-directed norms: heeding evidence, testing claims, trying to find out what is the case. Pseudoscience fakes participation in that truth-seeking practice.

Steve Stewart-Williams: That rings true to me.

Nikil Mukerji: That is why the pseudoscience charge cannot be a mere insult. One has to say what exactly is wrong with the claim or field. Does it avoid falsification? Does it ignore counterevidence? Does it only imitate the surface of science?

Steve Stewart-Williams: Exactly. Anyone can say, “You’re a pseudoscientist.” It’s like that Spider-Man meme where the two Spider-Men point accusingly at each other. The label alone doesn’t settle anything. You have to say what, specifically, is wrong with each claim.

Claims in evolutionary psychology are not all equally strong. Some are weak, some have been falsified – but some are excellent. The right approach is to avoid thinking “evolutionary psychology is all good” or “evolutionary psychology is all bad,” and instead to evaluate each claim on its merits.

Created by GWUP.

A Field That Can Be Wrong

Timur Sevincer: You said evolutionary hypotheses can be falsified. Could you give examples?

Steve Stewart-Williams: A famous example is the kin-selection explanation of same-sex sexual orientation, associated with E. O. Wilson. Same-sex sexual orientation is puzzling in evolutionary terms. Wilson suggested that it might be a form of kin altruism: instead of having children of one’s own, someone might help siblings or other relatives to have children, thereby passing on their genes indirectly through them.3 But people did the research, and the verdict seems to be that this isn’t the explanation.4

Timur Sevincer: Another example might be the dual-mating or ovulatory-shift idea: the idea that women might seek investment from one kind of man and “good genes” from another, with preferences shifting around ovulation. There were T-shirt smell studies and other work that initially attracted considerable attention,5 6 though the literature has since become more contested. How would you evaluate the state of the evidence today?

Steve Stewart-Williams: I’m very skeptical of the ovulatory-shift hypothesis. To be fair, the debate isn’t over; there are still people on both sides of the issue. But I’m much more persuaded by the people who say that the evidence hasn’t borne it out.

Timur Sevincer: How does evolutionary psychology fare after the replication crisis?

Steve Stewart-Williams: It hasn’t emerged unscathed, but I think it fares fairly well. It does better than social psychology, though not as well as behaviour genetics. The most robust claims in the field are those grounded in well-established theories from evolutionary biology: sexual selection theory, parental investment theory, parent-offspring conflict theory, kin selection theory. These are not free-floating speculations. They’re grounded in principles that have been demonstrated across many species. This is especially true for many sex differences.

Another reason the field has done well in certain areas is that it was seen as controversial from the outset. To persuade people, evolutionary psychologists have often had to clear a higher evidential bar. David Buss’s work on mate preferences, which found that men and women differ on average in how strongly they prioritize certain traits in long-term partners, used extensive cross-cultural evidence.7 8 Martin Daly and Margo Wilson’s work on homicide and step-parenthood, the so-called “Cinderella effect,” that children are at greater risk of abuse and violence from stepparents than from biological parents, drew on large archival datasets.9 The sex difference in interest in casual sex has multiple converging lines of evidence: cross-cultural evidence, real-world dating data, cross-species patterns, and links to prenatal hormonal exposure.

Nikil Mukerji: There is an interesting complication here. A low replication rate can be a warning sign. But in some pseudoscientific or ideological literatures, one finds suspiciously high positive-result rates: everything seems to confirm the preferred story. So a perfect replication rate can be suspicious as well.

Steve Stewart-Williams: Yes. To do replication properly, you need open science practices, preregistration, methods that could falsify the hypothesis, and ideally multiple research groups, including people with different prior commitments. Even if a claim is falsifiable in principle, one isn’t really doing science unless one uses methods that could in principle falsify it.

Social psychology deserves credit here. The fact that we know about its replication problems shows that many in the field are testing their claims and trying to improve. A low replication rate isn’t fatal if the field is actively checking, weeding out, and improving. The problem is that, until recently, they often weren’t.

The Ethical Trap

Nikil Mukerji: Some findings in evolutionary psychology are bound to annoy people, especially in certain political milieus. Are you concerned that this kind of science might play into the wrong hands? How do you deal with the ethics of communicating sex differences?

Steve Stewart-Williams: That’s a good and difficult question. Claims about sex differences can certainly be misused. They can be misused if people exaggerate the size of the differences. They can also be misused if people infer that, because a difference has an evolutionary basis, it’s therefore good or should be preserved. That can do harm. If we exaggerate differences, we may lower our expectations for one sex in certain domains.

But I have two responses. First, the sexes do differ on average, and I think there’s an evolutionary contribution to some of those differences. We can’t just lie about that. The right response is to tell the truth carefully and responsibly.

That means emphasising that most human sex differences are not huge.10 11 There’s a lot of overlap between the sexes. Everyone should get a fair chance. And the fact that something is natural, genetic, or partly shaped by evolution has no direct moral implications. Natural selection doesn’t tell us what’s right or wrong.

Second, denial can also do harm. It’s not the case that exaggerating sex differences is dangerous while minimising them is harmless. We can get this wrong in both directions.

Nikil Mukerji: So denial is wrong in principle, and one can also make a consequentialist case against it.

Steve Stewart-Williams: Exactly.

Timur Sevincer: This is also a communication problem. Many people hear “sex differences” and immediately think one is defending misogyny or fixed social roles. In my own teaching, I often begin by saying: there is usually substantial overlap between the sexes, most differences are small, evolutionary influences don’t make differences fixed or unmalleable, and a trait’s evolutionary origins don’t make it morally good.

Nikil Mukerji: And acknowledging average differences doesn’t necessarily make people conform to them. In some cases, it could even have the opposite effect: if people are aware of an average tendency, they may consciously decide not to follow it. Recognising statistical differences and encouraging individuality are not incompatible.

Steve Stewart-Williams: I think that’s right. It’s also important to take people’s concerns seriously. Some people worry that evolved sex differences will be used to revive old claims about male superiority or fixed gender roles. Given our history of anti-female sexism, that worry is understandable. But the right response is not to shut down the discussion. The right response is to discuss the evidence carefully.

Socialisation, Stereotypes, Patriarchy

Timur Sevincer: When people think about sex differences, they often default to three explanations: socialisation, stereotypes, and patriarchy. Boys and girls are raised differently; stereotypes become self-fulfilling; women are forced into roles by structures created by men. You deal with these explanations in the book. Where do they fall short?

Steve Stewart-Williams: I think “fall short” is the right phrase. It’s not that they have no merit. It’s impossible to believe that socialisation has no impact on behaviour. Stereotypes have an impact. Cultural factors matter. But they’re not enough on their own.

Take parental treatment. It’s often invoked as an explanation for sex differences. But there’s research suggesting that, at least in the West, parents don’t treat sons and daughters particularly differently in many important ways.12 Behaviour genetics also suggests that, within the normal range, the shared family home doesn’t have a massive impact on how people turn out.13 This doesn’t mean genes explain everything. The environment matters. But the simple parental-socialisation story is weaker than many people assume.14

On patriarchy, the gender-equality paradox is a serious problem for simple versions of the story. For many traits, sex differences are larger, not smaller, in wealthier, more individualistic, more gender-equal nations.15 16 That’s the opposite of what one would expect if the differences were due to strict sex roles or patriarchy. This doesn’t mean every difference follows that pattern, and it doesn’t mean culture is irrelevant. But it does challenge certain traditional sociocultural explanations for differences between the sexes.

On stereotypes, the work of has been a major influence on me. Stereotypes can be self-fulfilling to some extent, but the main causal direction is often from social reality to stereotype, not from stereotype to social reality.17 In the case of sex differences, stereotypes are partly shaped by actual average differences that people perceive in the world, and they correspond reasonably well to the actual sex differences.18 Then, in some cases, those stereotypes can amplify or galvanise the differences.

Nikil Mukerji: There is a habit of reasoning that often gets in the way here. Instead of asking whether a claim is true, one asks: “What makes you say that?” and “Who does this help?” Truth recedes into the background.

Steve Stewart-Williams: That can become a form of conspiracy theorising. If someone says, “You only believe that because you’re a man,” or “You only believe that because you’re defending your group,” that’s a claim about motive. But even if the motive attribution were true, it wouldn’t show that the claim is false. It’s essentially just an ad hominem argument.

What Denial Costs

Timur Sevincer: Many people understand that exaggerating sex differences can do harm. What is less obvious to many is that downplaying differences can also do harm. Can you give examples?

Steve Stewart-Williams: Sure. One is that, if we minimise sex differences in psychological disorders, we may fail to spot them in the less affected sex. ADHD often presents differently in girls than in boys, and the standard description fits boys better. That means girls with ADHD may be overlooked. Autism may also be overlooked in girls because it presents differently than in boys – for example, it tends to involve fewer repetitive behaviours. Conversely, depression in men involves substance use and aggression more than in women, so male depression may be missed.

There are social and occupational examples as well. If we ignore average differences in occupational interests, we may assume that every gender gap in a field is due entirely to bias. Bias exists, but sex differences in interests also matter. Men are, on average, more interested in things and things-related jobs; women are, on average, more interested in people and helping professions.19 If we ignore that, we may misdiagnose the cause of gaps and pour resources into interventions that don’t address the real causes.

It can also lead to coercive policies. If one reserves positions for one sex, or chooses a less qualified candidate to achieve numerical parity, one may reverse bias rather than remove it. On top of that, it can cast doubt on the competence of the supposedly benefited group. Even beneficiaries themselves may wonder whether they really deserved the position. And portraying STEM as saturated with sexism may deter some girls and women who would otherwise enjoy those fields.

Sexism exists. But exaggerating it, and ignoring the progress that has been made, can backfire.20 There’s also evidence of discrimination against men in some hiring contexts.21 22 This isn’t to deny discrimination against women; it’s just to say that discrimination alone can’t explain the gaps.

The Slippery Word “Gender”

Nikil Mukerji: In the book, you are quite critical of the concept of gender. Could you explain why?

Steve Stewart-Williams: I don’t think it’s a very useful concept, partly because it’s not just one concept. Sometimes “gender” is just a synonym for sex. Sometimes it refers to masculinity and femininity. Sometimes it refers to sex differences supposedly due to nurture rather than nature. Sometimes it refers to social roles, stereotypes, gender identity, or clusters of personality traits.

The nurture-based definition is especially problematic. It often assumes what should be demonstrated: namely, that nurture is the sole cause of the difference. Many recurring male-female differences involve both nature and nurture. If one defines gender as the nurture part and sex as the nature part, most female-male differences become partly sex differences and partly gender differences. That’s an awkward way to frame things.

Other definitions have other problems. If “gender” means personality profiles, for instance, then the claim that there are many different genders collapses into the trivial point that every person has a unique personality profile. At that point, we’re talking about personality, not something clearly linked to sex.

For these and other reasons, I prefer to talk about sex rather than gender. In biology, sex is defined by gametes: females are organised around the production of eggs; males around the production of sperm. Sex-linked traits such as chromosomes, genitals, hormones, masculinity, femininity, sex-typical behaviour, and personality traits don’t define sex. They’re connected to sex in different ways.

Why This Topic Can Set Rooms on Fire

Timur Sevincer: Why do sex differences, sexual behaviour, and evolution sometimes provoke such strong emotions? In principle, one could discuss them scientifically.

Steve Stewart-Williams: The topic is inherently combustible. A big part of the reason is our history of sexism against women. Early scientists made false and sexist claims about women’s intellectual abilities. So it’s understandable that people worry: if we talk about evolved sex differences, are we going back to Victorian ideas about male superiority and fixed roles?

But the science of sex differences actually refutes many of those early sexist claims. Shutting down the discussion is the wrong reaction. We should be able to say: yes, some past claims were wrong and sexist; no, that doesn’t mean every claim about sex differences is wrong or sexist.

Unfortunately, a modern trend on campus and elsewhere is to fight unwelcome ideas not with arguments and evidence, but with accusations, complaints to authorities, protests, occupations of classrooms, and so on. These are intimidation tactics as much as anything else. It’s anti-intellectual. In principle, anyone with any view can use intimidation tactics. Thus, intimidation cannot sort out who is right and who is wrong.

I had my own taste of this. A paper I wrote on sex differences in STEM23 caused an online controversy. The issue reached the equality, diversity, and inclusion office at the University of Nottingham’s UK campus. They did not like the paper! To their credit, though, they defended my academic freedom, and I was promoted to full professor despite listing the paper as one of my main pieces of work. But the experience was still worrying. I didn’t seriously think I’d lose my job, but I did wonder whether talking about what seemed to me commonsensical views might make it difficult to get another academic job.

That was part of why I started my Substack, The Nature-Nurture-Nietzsche Newsletter. I wanted a fallback. If the worst came to the worst, I wanted another way to make a living. And it’s worked out well: I’m no longer financially dependent on my academic job. This is a great position to be in. I’ve always tried to write honestly and openly about the topics I cover, even when knowing it might not be popular. But now I do so with a lot less trepidation.

Can Persuasion Still Work?

Nikil Mukerji: Some of these controversies are not only about evolutionary psychology itself, but also about deeper disagreements concerning evidence, reasoning, and the interpretation of scientific claims. How does one talk to people who have been taught that logic is a tool of oppression? They often fail to separate the truth of a claim from alleged motives for making it.

Steve Stewart-Williams: Even people who officially reject reason and evidence may still be moved by logical arguments. I admit that this is mostly anecdotal. But in social psychology there’s the idea of sleeper effects in persuasion: an argument may not change someone’s mind immediately, but it may work later.

Nikil Mukerji: My suspicion is that another causal factor is needed. Some people change their minds after reality punches them in the face. Then they remember that someone had explained the matter differently.

Steve Stewart-Williams: That could well be right. But persuasion is still worth attempting. It won’t work on everyone. Nothing will work on everyone. But across history, humanity has moved away from superstition toward more scientific ways of thinking. That suggests that slow persuasion is possible.

Can Evolutionary Science Inform Moral Reasoning?

Nikil Mukerji: In your book, you rightly reject the inference from “natural” to “good.” But Wilson and colleagues24 argue that evolutionary psychologists often overcorrect here: Hume’s point is only that ought cannot be derived exclusively from is, not that evolved facts have no ethical relevance. So when you say that the science of sex differences cannot answer policy questions because those are ultimately about values, how do you avoid turning a valid warning against “natural = good” into a stronger and false separation between facts and ethics? More concretely: should evolved sex differences alter our moral and political reasoning about fairness, coercion, individual freedom, and the costs of eliminating gender gaps — and if so, exactly how?

Steve Stewart-Williams: I don’t think anyone argues that evolved facts have no ethical relevance. They just argue that the fact that something has an evolutionary origin doesn’t necessarily mean it’s good – or bad, or anywhere in between. That’s all I argue, anyway.

An example: It might be the case that, if a given sex difference has an evolutionary origin, it would be hard to eliminate, and that doing so would do more harm than good. As a result, we might decide that we shouldn’t try to eliminate it. But the reason for that decision wouldn’t be that the sex difference is natural; it would be that trying to eliminate it would do more harm than good. In other words, we’d be dealing with a consequentialist argument, not an argument from nature.

Importantly, this cuts both ways. If eliminating a socially constructed sex difference would do more harm than good, then we shouldn’t do that either, even though the difference isn’t “natural.” And if eliminating a natural difference would boost general well-being, we should do it despite its natural origins. In itself, the nature-nurture question is irrelevant to the ethical question.

We can turn the tables here as well: Why should we exclude certain facts from our ethical reasoning just because they happen to have an evolutionary origin? To do so is to risk falling prey to an anti-naturalistic fallacy!

What Skeptics Should Do

Nikil Mukerji: What could skeptical organisations such as the GWUP do to support work on evolutionary psychology? One project might be to investigate the charge that evolutionary psychology is pseudoscience. If one calls a real science pseudoscience, one is denying it legitimate scientific status. That’s a form of science denial.

Steve Stewart-Williams: I hadn’t thought about it exactly that way, but it’s interesting. Some contemporary criticisms of evolutionary psychology echo arguments made earlier by critics of sociobiology such as Stephen Jay Gould, Richard Lewontin, Stephen Rose, and others.

I do think there’s genuine science denial around evolutionary psychology, and around behaviour genetics as well. Both fields posit genetic or evolutionary contributions to behaviour, which many people dislike. The difficulty is that, although there’s science denial on both the right and left side of the political spectrum,25 academia is predominantly left-leaning, and thus left-leaning forms of science denial are less likely to be labeled as such. In that way, politics can intrude on science and suppress it.

Nikil Mukerji: Colin Wright suggested a useful skeptical task: look at what critics are actually saying, systematise their assertions, test whether they are representative of the literature, and present the strongest version rather than a straw man. That matters because critics often respond: “Nobody actually believes that.” Skeptics need textual evidence.

For the GWUP, this could mean identifying the sources and authors behind the claim that evolutionary psychology is pseudoscience, building a bibliography, and analysing representative claims.

Steve Stewart-Williams: That sounds like a worthwhile project. You have to be fair and careful, but also willing to call science denial science denial when that’s what it is.

Nikil Mukerji: That is a good place for skeptics to stand: not on the side of a political tribe, but on the side of careful distinctions, fair evidence, and criticism that applies in every direction.

Steve Stewart-Williams: Exactly. Evolutionary psychology is not perfect. No science is. Some hypotheses have failed, and others will fail in the future. But to say that the whole field is worthless or pseudoscientific isn’t to give credit to what it’s achieved. The better approach is to examine claims one by one, ask what evidence supports them, ask what evidence could refute them, and keep moral questions separate from scientific ones.

Photo Credit: Thong Wei Sen, White Photo Gallery.

Prof. Steve Stewart-Williams

Steve Stewart-Williams is a professor of psychology and the author of A Billion Years of Sex Differences: How Evolution Shaped the Minds of Men and Women. The book explores the extent to which some average psychological differences between men and women reflect evolutionary influences.

Follow Steve on Twitter/X for more psychology, evolution, and science.

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Costello, W., Sedlacek, A. G. B., Durkee, P. K., Crosby, C. L., Hahnel-Peeters, R. K., & Buss, D. M. (2026). Evolutionary psychology hypotheses are testable and falsifiable. American Psychologist, 81, 1-24.

Frankfurt, H. G. (2005). On bullshit. Princeton University Press.

Wilson, E. O. (1978). On human nature. Harvard University Press.

Bobrow, D., & Bailey, J. M. (2001). Is male homosexuality maintained via kin selection? Evolution and Human Behavior, 22, 361-368.

Gangestad, S. W., & Thornhill, R. (1998). Menstrual cycle variation in women’s preferences for the scent of symmetrical men. Proceedings of the Royal Society of London. Series B: Biological Sciences, 265, 927-933.

Thornhill, R., & Gangestad, S. W. (2003). Evolutionary theory led to evidence for a male sex pheromone that signals symmetry. Psychological Inquiry, 14, 316-323.

Buss, D. M. (2003). Sexual strategies: A journey into controversy. Psychological Inquiry, 14, 219-226.

Walter, K. V., Conroy-Beam, D., Buss, D. M., Asao, K., & Sorokowska, A. (2020). Sex differences in mate preferences across 45 countries: A large-scale replication. Psychological Science, 31, 408-423.

Daly, M., & Wilson, M. (2008). Is the “Cinderella effect” controversial? In C. Crawford & D. Krebs (Eds.), Foundations of evolutionary psychology (pp. 383-400). Erlbaum.

Stewart-Williams, S., & Thomas, A. G. (2013a). The ape that thought it was a peacock: Does evolutionary psychology exaggerate human sex differences? Psychological Inquiry, 24, 137-168.

Stewart-Williams, S., & Thomas, A. G. (2013b). The ape that kicked the hornet’s nest: Response to commentaries on “The Ape that Thought It Was a Peacock.” Psychological Inquiry, 24, 248-271.

Lytton, H., & Romney, D. M. (1991). Parents’ differential socialization of boys and girls: A meta-analysis. Psychological Bulletin, 109, 267-296.

Plomin, R., & Daniels, D. (1987). Why are children in the same family so different from one another? Behavioral and Brain Sciences, 10, 1-16.

Harris, J. R. (1995). Where is the child’s environment? A group socialization theory of development. Psychological Review, 102(3), 458-489.

Stoet, G., & Geary, D. C. (2018). The gender-equality paradox in science, technology, engineering, and mathematics education. Psychological Science, 29, 581-593.

Herlitz, A., Hönig, I., Hedebrant, K., & Asperholm, M. (2025). A systematic review and new analyses of the gender-equality paradox. Perspectives on Psychological Science, 20, 483-519.

Jussim, L., Crawford, J. T., Anglin, S. M., Stevens, S. T., & Duarte, J. L. (2016). Stereotype accuracy: One of the largest and most replicable effects in all of social psychology. In T. D. Nelson (Ed.), Handbook of prejudice, stereotyping, and discrimination (2nd ed., pp. 31-63). Psychology Press.

Swim, J. K. (1994). Perceived versus meta-analytic effect sizes: An assessment of the accuracy of gender stereotypes. Journal of Personality and Social Psychology, 66, 21-36.

Su, R., Rounds, J., & Armstrong, P. I. (2009). Men and things, women, and people. Psychological Bulletin, 135, 859-884.

Ceci, S. J., Kahn, S., & Williams, W. M. (2023). Exploring gender bias in six key domains of academic science: An adversarial collaboration. Psychological Science in the Public Interest, 24, 3-92.

Williams, W. M., & Ceci, S. J. (2015). National hiring experiments reveal 2:1 faculty preference for women on STEM tenure track. Proceedings of the National Academy of Sciences, 112, 5360-5365.

Schaerer, M., du Plessis, C., Yap, A. J., et al. (2023). On the trajectory of discrimination: A meta-analysis and forecasting survey capturing 44 years of field experiments on gender and hiring decisions. Organizational Behavior and Human Decision Processes, 179, 104290.

Stewart-Williams, S., & Halsey, L. G. (2021). Men, women and STEM: Why the differences and what should be done? European Journal of Personality, 35, 3-39.

Wilson, D. S., Dietrich, E., & Clark, A. B. (2003). On the inappropriate use of the naturalistic fallacy in evolutionary psychology. Biology and Philosophy, 18, 669-682.

Washburn, A. N., & Skitka, L. J. (2018). Science denial across the political divide: Liberals and conservatives are similarly motivated to deny attitude-inconsistent science. Social Psychological and Personality Science, 9, 972-980.

Why We Can't Talk Honestly About Sex Differences

Steve Stewart-Williams — Thu, 18 Jun 2026 09:51:38 GMT

Emma Stone and Steve Carell in ‘Battle of the Sexes’ (20th Century Fox).

I’m happy to report that I’ve just had an op-ed published in The Independent, titled “A Century of Evidence Tells Us Men and Women Are Different - Let’s Stop Pretending They’re the Same.” The piece summarizes some of the key arguments in my new book, A Billion Years of Sex Differences.

The road to publication was bumpier than I’d expected, ironically for reasons related to the very phenomenon the article highlights. Although the science of sex differences has advanced enormously over recent decades, discussing the topic remains contentious. Even modest, commonsensical claims can provoke strong reactions.

As I explain in the piece - and in the book - I got my first taste of this several years ago when I published an academic paper with Lewis Halsey about gender gaps in STEM professions. We argued that, although bias and barriers are part of the explanation, average sex differences in career-related interests and other relevant traits also contribute. I soon found myself at the center of an online controversy and was reported to my university’s equality, diversity, and inclusion office.

To the university’s credit, nothing came of the complaint. But the episode drove home an uncomfortable truth: Talking honestly about sex differences is still something of a minefield.

The op-ed explores why that is, and why I think the controversy is misplaced. Recognizing that men and women differ, on average, in certain traits is not incompatible with treating everyone equally and with respect. Indeed, if we care about improving people’s well-being, we have no choice but to follow the evidence wherever it leads.

Here’s a brief excerpt from the piece.

Why, then, does the topic generate so much heat? …
[One] reason is that many assume that generalisations about the sexes provide intellectual ammunition for sexism…
[But] we can’t just assume that differences imply deficiencies. As psychologist Diane Halpern observed, everyone agrees that men’s and women’s genitals are different, but no one would argue that either sex’s genitals are superior. The same applies to many psychological sex differences.
Indeed, it’s ironic that, in an age where we rightly celebrate differences and diversity, we often get outraged when anyone points any out. Not exactly tolerance of diversity!
Rather than supporting old-fashioned sexist views, the science of sex differences actively undermines them. It shows, for example, that there are no average sex differences in IQ (much to the surprise and disappointment of both sexes). And if either sex comes off worse, it’s men: men have higher rates of violence and criminality, for instance, and are more likely to abandon their children. Unless we think these are desirable traits, the science paints men in a less favourable light.
The larger point is that a commitment to equality doesn’t entail the denial of sex differences. We can treat men and women fairly and respectfully even if they’re not identical on every trait.

You can read the whole article here. And you can order A Billion Years of Sex Differences here.

Follow me on Twitter/X for more psychology, evolution, and science.

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Steve

Mate Choice as Selective Breeding

Steve Stewart-Williams — Tue, 16 Jun 2026 16:25:46 GMT

Image: GPT5.

This post is an excerpt from my new book A Billion Years of Sex Differences. You can access the full collection here, or pick up a copy of the book here.

In this installment, we’ll see…

Why mate preferences aren’t just products of evolution but causes of evolution as well
Why the widespread idea that women are the sexual selectors in our species is only half true
How men’s and women’s desires helped shape each other’s evolution
How something as intangible as a preference can sculpt physical anatomy
Why, when it comes to physical attractiveness, females in our species have the larger “peacock’s tail” - a reversal of the usual pattern in nature

12 Things Everyone Should Know About the Psychology of Victimhood

Steve Stewart-Williams — Sat, 13 Jun 2026 10:01:31 GMT

Photo by Vika_Glitter on Pixabay.

The last month has been a blur, as I’ve raced around the world promoting my new book, A Billion Years of Sex Differences. Among other things, I’ve given interviews to The Scottish Herald, Skeptiker magazine, and The Telegraph; recorded multiple podcasts; appeared at the HowTheLightGetsIn festival; and written an op-ed for The Independent. I’ve also received some behind-the-scenes pushback on the book. More on that later.

Last week was particularly hectic. I flew from London to Austin, Texas, to make my second appearance on ’s Modern Wisdom podcast, and to take part in a roundtable with Chris, , and Macken Murphy. Four hours of podcasting on four hours’ sleep - followed by my first ride in a self-driving car!

It’s all been great fun, but it hasn’t left me much time for Substack. So rather than rushing out something new this weekend, I thought I’d republish one of my favorite earlier posts: one I first published before many of my current subscribers came on board. I hope you enjoy it. Regular programming will resume next week!

“Victims have never been in short supply in the world, but the rush to identify oneself as a victim is rather a new feature of modern life.”

-Joseph Epstein, The Joys of Victimhood (1989)

Victimhood has always had a certain moral cachet. In recent years, however, it’s become one of the most powerful currencies in the social marketplace. Whereas people once sought status through highlighting their achievements, today they often do so by broadcasting their wounds.

The philosopher Bertrand Russell saw it coming. In a 1943 essay titled The Superior Virtue of the Oppressed, he warned of a growing tendency to see victimhood not just as a reason for sympathy, but as a badge of moral superiority. Since then, the trend has only accelerated.

Take Rachel Dolezal, the White woman who presented herself as Black and rose to a leadership position in the NAACP before her true ancestry was revealed. Or recall the actor Jussie Smollett, who staged a hate crime against himself by hiring two acquaintances to beat him up. These are baffling cases - until we recognize the powerful incentive, in today’s culture, of being a victim.

This isn’t to deny, of course, the reality of suffering or oppression. There are genuine victims in the world, and they deserve our compassion and support. However, when victim status becomes a path to prestige or power, it creates an unfortunate incentive for people to take on the victim role - sometimes unwittingly, sometimes strategically.

In this installment of the “12 Things Everyone Should Know” series, we’ll explore what the latest psychological research reveals about victimhood mentality: how it distorts perception, encourages bad behavior, and poisons intergroup relations.

You can access the full collection of “12 Things Everyone Should Know” posts here.

1. Victimhood as a Personality Trait

Psychologists have identified a personality trait they call the Tendency for Interpersonal Victimhood (TIV). It reflects a chronic sense of being wronged, and includes four key components:

Need for recognition - the desire to have one’s suffering acknowledged, validated, and empathized with
Moral elitism - a belief in one’s moral superiority, and the moral depravity of one’s opponents
Lack of empathy - obliviousness to other people’s suffering
Rumination - a tendency to obsess over problems, unpleasant experiences, and perceived slights

2. Victim Signaling as a Manipulation Tactic

Not every claim of victimhood is genuine. People with manipulative, narcissistic, or psychopathic tendencies sometimes weaponize victimhood: They exaggerate harm, fabricate grievances, and leverage sympathy to exploit other people’s better nature. As psychologist Adam Grant put it: “Constantly claiming to be a victim is not a sign of virtue. It’s a strategy for narcissists and psychopaths to get ahead.”

Source: Ok et al. (2021).

Are Sex Differences Compatible with Feminism?

Steve Stewart-Williams — Fri, 12 Jun 2026 11:40:24 GMT

I recently made my second appearance on Ricardo Lopes’ Dissenter podcast to discuss my new book, A Billion Years of Sex Differences. We had a fun, wide-ranging conversation about the science of sex differences, human nature, and some of the most contentious debates in contemporary psychology. Here are some of the topics we covered:

Why I’m skeptical of the sex-gender distinction
Whether parents shape sex differences
Whether the science of sex differences is compatible with feminism
The largest psychological sex differences in our species
What drives the evolution of sex differences (hint: It’s not that sperm are cheaper than eggs)
Sex differences in career-related interests
Sex differences in cognitive abilities
The trans phenomenon from an evolutionary perspective
Three approaches to dealing with sex differences: gender-role traditionalism, gender-role progressivism, and gender-role individualism

Here’s a clip from the episode, where I discuss trans and nonbinary identification:

And here’s a clip where I discuss the three main approaches to dealing with sex differences, both as individuals and as a society:

The full episode is available on Apple Podcasts, Spotify, or wherever you get your podcasts. It’s also available on Ricardo’s Dissenter YouTube channel.

Buy A Billion Years now

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Steve Stewart-Williams

Three New Papers on Wokeness in Psychology

Steve Stewart-Williams — Wed, 10 Jun 2026 14:27:11 GMT

Image: ChatGPT.

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In Case You Missed It…

Psychology has always been influenced by the moral fashions of the time. In the age of “wokeness,” however, this process has gone into overdrive. According to a growing number of critics, psychology has become increasingly ideological, increasingly activist, and increasingly hostile to dissenting views.

But the counterrevolution seems to be gaining steam. More and more psychologists are pushing back against the woke turn in psychology, and trying to reclaim a more empirically based, more politically moderate, and less identitarian approach to the field.

In this post, I highlight some important recent examples of this pushback: three papers that explore and critique different aspects of the woke trend. Specifically, they look at the suppression of politically inconvenient findings, the erosion of public trust in psychology, and the growing tension between therapeutic practice and politicized conceptions of human suffering.

You might not agree with every claim made in these papers. But I hope you agree that they all raise important questions - questions we ignore at our peril.

1. Suppressing Science

The first paper examines what authors Stephen Ceci and Wendy Williams call the “dominant gender narrative”: the widespread belief that women face pervasive discrimination at every stage of their scientific careers. The paper argues that the strongest available evidence no longer supports this claim, but that researchers who point this out often face hostility or attempts at silencing, rather than open scientific debate. Here’s an excerpt from the piece.

The “dominant gender narrative” in science holds that bias against women is pervasive and occurs in every domain, including tenure-track hiring, letters of recommendation, awards, grants, journal publications, authorship assignment, citations, salaries, promotions, and teaching evaluations. Many of these claims are repeatedly broadcast despite their nullification by larger, stronger studies and meta-analyses that do not find gender bias. Because these stronger studies are cited less often, there exists a false belief among many faculty that gender bias is omnipresent in the tenure-track academy. As an example of this false belief, 248 U.S. faculty were surveyed about their beliefs regarding gender bias. They overestimated the extent of such bias in every domain. We illustrate this misalignment of beliefs by focusing on just one of the many domains in which bias against women is alleged but has been nullified by stronger studies: tenure-track hiring. We show that the dominant narrative of pervasive bias in favor of hiring men is not supported by the evidence. The reality is the opposite of what is believed, with women preferred over comparable men: multiple sources of evidence demonstrate that in tenure-track hiring in the United States and many European countries, women have an advantage over equally-accomplished men. Yet, the claim of bias against hiring women faculty continues to be widely cited in the premier science media. Challenging the gender narrative should be part of normal scientific discourse; however, doing so often evokes a backlash—as documented in testimonials by researchers who have been attacked.

I was one of the researchers Ceci and Williams contacted for testimonials, and I shared details of my own (relatively minor) experience of backlash. Specifically, I shared an excerpt from my new book, A Billion Years of Sex Differences, in which I discuss the heated reaction I received to a paper I wrote with Lewis Halsey about the causes of sex differences in STEM. Ceci and Williams quoted some of the excerpt in their piece, making it the first academic paper to cite A Billion Years.

Finally, we received a summary about the current state of affairs by Steve Stewart-Williams, an evolutionary scientist who conducts research on gender (Stewart-Williams, in press), that is worth repeating here:
“A vocal minority see positing sex differences as more than a mere social faux pas or difference of opinion, and view it instead as a moral transgression. For individuals in this camp, the idea that the sexes are naturally identical has become a sacred belief. Disagreement is seen not as an honest mistake or interesting challenge to be evaluated, but as sacrilege. And the typical response to sacrilege isn’t a tolerant appreciation of the wonderful diversity of human lifeways: ‘Well, I’m not personally into sacrilege, but if other people are, who am I to judge?’ Instead, the typical response is to censor, to silence, to cancel, punish, and shun.”

Citation: Ceci, S. J., & Williams, W. M. (2026). Organized dogmatism controls the message about gender bias in the academy. Journal of Controversial Ideas, 6, 4.

You can access the paper here for free.

The Truth About Sexism in Science

It’s an idea so widely accepted that we rarely think to question it: Women face rampant discrimination in science, while men coast along on a cushion of unearned privilege. You’ll hear this claim echoed everywhere, from the most prestigious scientific journals to the pages of…

a year ago · 46 likes · 15 comments · Steve Stewart-Williams

2. The Cost of Woke Psychology

The second paper argues that psychology’s increasingly activist and identitarian public face may be undermining trust in the field. According to author Travis Proulx, many people - including many on the political left - feel alienated by the discipline’s moralizing tone, unrealistic worldview, and ideological conformity. The proposed remedy is simple: less moral grandstanding and more intellectual humility. As Proulx writes:

Given the predominant role of taxpayers in funding our research, we should be concerned that the voting public may justifiably perceive our science as emphasizing activist visions of what should be over the empirical complexities of what is. Ensuring public trust will depend on re-embracing persuasive intellectual humility and eschewing the identitarian vernacular and deficit model pedagogy that currently characterizes our public-facing messaging…
Psychologists know that public trust decreases to the extent that manifest ideological leanings diverge from their own. We also know that progressive activism within our science represents views that diverge from ≈90% of the Western public – including most left-wingers. Alarming, when roughly 90% of research funding ultimately derives from a public whose enthusiasm for funding scientific research decreases with perceived social distance from scientists. Western cultural institutions are moving on from monomaniacal identitarianism, re-embracing the intellectual humility to acknowledge that it depends. Will we join them in escaping this ‘identity trap’, or spiral into an ‘Endless Summer 2020’?

Citation: Proulx, T. (2026). An ‘outgroup’ public won’t trust a progressive ‘ingroup’ psychology. Current Opinion in Psychology, 70, 102316.

You can access the paper here for free.

3. How Victimology is Killing Therapy

The third and final paper focuses on cognitive behavioral therapy (aka CBT). Authors Richard Redding, Robert Maranto, and Nathan Honeycutt argue that therapists and clinical psychologists increasingly emphasize oppression and victimhood over personal agency - a shift they fear could undermine one of psychology’s most effective treatments, and make therapy less accessible to clients who don’t share progressive political views.

Cognitive behavioral therapy (CBT) rests on the premise that individuals possess personal agency to change their life circumstances. At the same time, given growing political homogeneity within psychology, views of individual agency are increasingly being displaced by greater emphasis on conceptualizing distress as reflecting systemic oppression. Drawing on research concerning these frameworks, this article briefly examines the implications of these trends for CBT in the United States. Specifically, we outline three potential concerns, including declining interest in traditional CBT, reduced value alignment between therapists and non-liberal clients, and possible shifts in the theoretical and practical focus of CBT. We conclude by discussing implications for graduate training and the importance of sociopolitical competence and diversity in clinical education…
It would be quite unfortunate if fewer young therapists are attracted to learning or practicing CBT, given its proven effectiveness. Or, if they corrupt it through a politicization that alters its fundamental approach, aims, and therapeutic strategies in favor of strategies that serve a political agenda. This will result not only in reduced therapeutic efficacy but in some cases therapy that is harmful or iatrogenic. It would also be unfortunate if politically moderate or conservative clients cannot find a therapist in their community who understands their values and problems or only one who practices a politicized form of CBT that is a very poor match for their sociopolitical values…
[W]e are hopeful that enough clinicians will “resist the ideological encroachment into the field to rebuff politicized narratives, to re-assert the primacy of individual clients in all their complexity.”

Citation: Redding, R. E., Maranto, R., & Honeycutt, N. (2026). Is the victimology worldview of many young therapists ill-suited for cognitive behavior therapy? Current Opinion in Psychology, 70, 102313.

You can access the paper here for free. Note that it’s part of a special issue in Current Opinion in Psychology focusing on identity and politicization in behavior therapy.

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Social-Justice Therapy

a year ago · 44 likes · 9 comments · Steve Stewart-Williams

Will papers like these be enough to turn the tide on wokeness in psychology? I’m not sure. But with the number of such papers growing steadily, I feel more optimistic today than I did when I had my own taste of ideological backlash five or so years ago.

Follow me on Twitter/X for more psychology, evolution, and science.

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Fighting the Good Fight Over Sex Differences

Steve Stewart-Williams — Sun, 07 Jun 2026 08:06:48 GMT

Steve Stewart-Williams on Sex Differences and Human Nature

I recently rejoined political scientist on the Good Fight podcast to discuss my new book, A Billion Years of Sex Differences. We had a wide-ranging conversation about what the science says about the differences between men and women, and why the topic remains so controversial.

Here are some of the many topics we covered:

The three main types of sex differences: Mars-and-Venus differences, Mars-and-Venus-plus-exceptions, and statistical or “fuzzy” differences
Four biases that distort the science of sex differences: the alpha bias, beta bias, gamma bias, and delta bias
The dangers of exaggerating sex differences - and of minimizing them
Why gay men tend to have more casual sex than straight men, while lesbians tend to have less than straight women
Why humans are neither strictly monogamous nor highly polygynous, but somewhere in between
The evolutionary roots of male aggression - and how civilization works to suppress it
What drives sex differences in STEM fields
The gender-equality paradox: why sex differences are often larger, rather than smaller, in wealthier, more egalitarian societies
How even small differences at the mean can give rise to large differences at the extremes - what I call the tail-of-the-distribution effect
Greater male variability in cognitive abilities: fact or fiction?

The episode is available on Spotify, Apple Podcasts, or wherever you get your podcasts. You can also find it on Yascha’s Substack or the Persuasion Substack, along with a transcript of the conversation.

Yascha Mounk

Steve Stewart-Williams is a professor of Psychology at the University of Nottingham’s Malaysia campus and runs The Nature-Nurture-Nietzsche Newsletter. His latest book is A Billion Years of Sex Differences…

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25 days ago · 4 likes · Yascha Mounk

If you want to dig deeper into these issues, you can pick up a copy of A Billion Years of Sex Differences here.

Follow me on Twitter/X for more psychology, evolution, and science.

How You Can Support the Newsletter

If you like what I’m doing with The Nature-Nurture-Nietzsche Newsletter and would like to support my work, please consider upgrading to a paid subscription. A paid subscription gets you:

Full access to all new posts and the archive
Full access to exclusive content such as my “12 Things Everyone Should Know” posts, Linkfests, and other regular features
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On top of that, you’ll be helping support my efforts to explore important ideas and promote open, non-politicized scientific inquiry.

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Steve Stewart-Williams

Did Our Ancestors Choose Their Mates?

Steve Stewart-Williams — Sat, 06 Jun 2026 09:07:05 GMT

Image: ChatGPT.

This is the latest excerpt from my book A Billion Years of Sex Differences, released on June 4. You can access the full collection here, and pick up a copy of the book here.

In this installment, I tackle a common objection to evolutionary explanations for human mate preferences: the idea that our ancestors didn’t choose their own mates, because marriages were arranged and women were often coerced into relationships. Among other things, we’ll look at:

How arranged marriage can coexist with individual mate choice
Why mate preferences aren’t relevant only at the start of a relationship
How affairs and elopements may have helped shape human evolution
Why humans may have stronger mate preferences than other animals
How parental interference may help explain the evolution of romantic love

Let's Keep Talking About Sex Differences

Steve Stewart-Williams — Thu, 04 Jun 2026 18:23:34 GMT

A Billion Years is Out!

My new book, A Billion Years of Sex Differences, is finally on the shelves.

It's about how evolution shaped the minds of men and women - and why it matters today.

After finishing my previous book, The Ape That Understood the Universe, I swore I’d never write another. But then I was stuck at home during the pandemic, and I had an idea for a book that I couldn’t shake off. So I thought, “Fine, just one more...”

And now, five years later, it’s a real thing in the world. It feels great!

This is the last one, though...

If you’d like to read a sample or pick up a copy of A Billion Years of Sex Differences, you can do so here.

My Appearance on the Keep Talking Podcast

In other news, the first interview I recorded for A Billion Years was released today, to coincide with the release of the book. It was on ’s excellent Keep Talking podcast. These are some of the many topics we covered:

How I fell in love with the evolutionary psychology of sex differences
Whether A Billion Years of Sex Differences will destroy my career
The main sex differences in our species
Why human sex differences are relatively modest compared to those in most other mammals
My controversial paper on sex differences in STEM
My crazy plan to start a Substack so I wouldn’t be financially dependent on my academic job - and how, by some kind of miracle, it actually worked
Why the science of sex differences matters
How we should respond to sex differences as individuals and as a society: gender-role traditionalism vs. gender-role progressivism vs. gender-role individualism

The episode is available on Apple Podcasts, Spotify, or wherever you get your podcasts. You can also find it on Dan’s Keep Talking Substack and Keep Talking YouTube channel.

A New Review of A Billion Years

Last but not least, the latest review of A Billion Years of Sex Differences has just appeared in Male Psychology magazine. It’s written by Dr. John Barry, whose groundbreaking work is discussed in the book. Here’s an excerpt.

[P]eople who don’t like evolutionary psychology, or those who are wed to the idea that gender roles should be rejected on principle, are probably going to find reasons not to like this book. But for everyone else, it’s hard to find examples of where Stewart-Williams puts a foot badly wrong. This book is a mine of interesting and sensible information, engagingly written, and I thoroughly recommend it.

You can read the whole review here. And you can check out previous reviews of the book in The Times and The Guardian.

Buy A Billion Years now!

Follow me on Twitter/X for more psychology, evolution, and science.

How You Can Support the Newsletter

If you like what I’m doing with The Nature-Nurture-Nietzsche Newsletter and want to support my work, there are several ways you can do it.

Like and Restack - Click the buttons at the top or bottom of the page to boost the post’s visibility on Substack.
Share - Send the post to friends or share it on social media.

Upgrade to Paid - A paid subscription gets you:
- Full access to all new posts and the archive
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If you could do any of the above, it’d be much appreciated. The support of readers like you helps keep the newsletter going.

Thanks!

Steve

Trad Wives and Sex Differences in Career Choice

Steve Stewart-Williams — Sun, 31 May 2026 11:43:16 GMT

Photo by Frank Ockenfels/AMC.

I recently sat down with the Telegraph’s science editor, Sarah Knapton, to discuss a range of topics related to my book, A Billion Years of Sex Differences.

We kicked things off with the trad wife phenomenon. Below is an excerpt on the topic from Sarah’s article. Note that the title of the article - “‘Trad wives’ are a myth as women always worked” - is somewhat misleading as women didn’t always work, at least outside the home. My point was that, among our hunter-gatherer ancestors, both sexes worked outside the home, not just men. Why does it matter what our hunter-gatherer ancestors did? Because we spent most of our evolutionary history as hunter-gatherers, and thus this way of life was the crucible in which human nature evolved.

The “trad wife” or “traditional wife” trend has spread through social media, and promotes a lifestyle in which the husband is the sole financial provider, leader and protector, while the woman is dependent and submissive…
It is supposed to be based on historical gender roles, which proponents claim have been lost in modern life.
But Dr Steve Stewart-Williams, of the University of Nottingham Malaysia, whose book ‘A Billion Years of Sex Differences’ is published on June 4, said there was little evidence to support the phenomenon.
“The idea that this is the natural arrangement for our species is, I think, very, very weak,” he explained.
“For most of our evolutionary history, women weren’t just at home with the kids; they had jobs outside the home, gathering food and the like.
“[And for] most of [our] evolutionary history, women were not isolated. They were hanging out with other adults most of the day.”

To be clear, if people want to adopt the trad wife lifestyle, all power to them. The fact that it’s not the natural arrangement for our species doesn’t mean it’s inherently bad - most ways we live today aren’t natural. My guess is that this lifestyle wouldn’t suit most women, at least not for long. But people differ, and it would no doubt suit some. And that’s what we should be thinking about when making life decisions: what would suit us, not what’s natural or unnatural.

A second topic Sarah and I discussed was sex differences in career choice. This is arguably the most controversial topic I address in A Billion Years of Sex Differences, and the one I’ve got the most grief about in the past. Here’s another excerpt:

Dr Stewart-Williams said he accepted that men and women naturally gravitate toward different types of work – with women often preferring people or language-focused roles, such as psychology, the humanities, teaching and caring professions.
Conversely, fields that are less people-oriented, such as computer science, physics, and mathematics, tend to naturally remain male-dominated.
As societies become more developed and women gain more rights and opportunities, the gender divide in careers becomes greater not less, a phenomenon known as the “gender equality paradox”.
In wealthier nations, people have the financial freedom to follow their dreams and individuality, which ends up giving natural, innate differences more room to grow, he argues…
“For a lot of sex differences, you’d expect them to be smaller in gender-equal nations, wealthier nations, nations with higher levels of human development, but instead they’re often larger,” he said.
Dr Stewart-Williams said individuals should be able to pursue whatever interests them, whether that meant women choosing STEM professions or men entering teaching and caring professions.
But he warned that because the sexes have different average interests, trying to force a strict 50-50 gender balance in every occupation is unnatural.

I’d quibble with the wording of that final line. I do think that trying to force a strict 50-50 sex ratio in every occupation would be unwise, as it would inevitably mean nudging, bribing, or cajoling some people to go into areas less aligned with their interests. But I wouldn’t say a 50-50 gender balance is unnatural - first, because none of our modern occupations are natural, and second, because the tacit assumption in this context is that “unnatural” means “bad.” It doesn’t. Plenty of unnatural things are very good, and plenty of natural things are terrible.

Note as well that I don’t deny that discrimination and socialization help shape the sex ratios of different fields. I just don’t think they’re the entire explanation. Other factors - in particular, average sex differences in career-related interests - also play a role.

You can read the whole Telegraph piece here. And you can order A Billion Years of Sex Differences here.

Follow me on Twitter/X for more psychology, evolution, and science.

From the Archive

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Steve

Political Breakups, Female-Fearing Birds, and Women Outearning Men

Steve Stewart-Williams — Sat, 30 May 2026 12:49:00 GMT

Photo by Vanessa Murrieta on Unsplash

In Case You Missed It…

Welcome to the May 2026 edition of the N³ Newsletter Linkfest: a collection of links to papers and articles that grabbed my attention over the last month. On the menu today…

Surprising news about the gender pay gap
Psychological myths that won’t die
The political divide separating men and women
The media’s hate-crime blind spot

And we’ll ask: Can positive thinking extend your lifespan? Are some delinquents born while others are made? And can you tell how intelligent someone is from just a few seconds of video?

Around half the items are free to read for everyone; the rest are behind a paywall. I tend to put the spicier content behind the paywall, so if you want a taste of that, consider becoming a paid subscriber.

You can access the complete collection of Linkfests here.

Political Breakups

More than one in three Americans has lost at least one family relationship, friendship, or romance over politics. Democrats are especially prone to such “political breakups” - and people who’ve experienced them tend to see their political opponents not merely as wrong but as selfish and extreme. [Link.]

Murderous Intent

Millions of people in the US have seriously contemplated shooting someone. [Link.]

Birds Fear Women More Than Men

A curious finding from Europe: City birds are more afraid of women than men, consistently fleeing sooner when approached by a woman. This pattern was found in five out of five countries, survived a battery of controls, and left researchers scratching their heads about what on earth might be going on. [Link.]

Humorless Humans, Serious Monkeys

Here are two potentially related findings I happened to spot this month:

In human societies with stricter social norms and lower tolerance for deviance, people are less likely to make jokes or be skilled at humor. [Link.]
In monkey and ape societies with despotic leaders, adults are less likely to clown around and have fun. [Link.]

The Latest on the Gender Pay Gap

Among young Australians, women now earn more than men. The same pattern has also been observed in many US and UK cities. It’s a real and growing trend. [Link.]

The Replication Crisis

Non-replicable research gets cited more than replicable research. This is consistent with what I call Steve’s Law: Boring findings and non-PC findings are more replicable than interesting or PC ones. [Link.]

Psychological Myths and Misconceptions

People believe a lot of myths about psychology - even after they’ve taken an intro psych class. The myths in question include everything from learning styles to repressed memories to sugar-induced hyperactivity. For some reason, women believe more psychological myths than men. [Link.]

Overthinking Nature and Nurture

Steve Stewart-Williams — Thu, 28 May 2026 19:03:56 GMT

What happens when a secular evolutionary psychologist and a Christian podcaster sit down to talk about human nature? More agreement than you might expect.

I recently joined Joseph Holmes on The Overthinkers podcast to discuss nature, nurture, and the evolution of sex differences. Among other things, we discussed:

My new book A Billion Years of Sex Differences
Why genetic and evolutionary explanations for human behavior make so many people uncomfortable
Six lines of evidence that many sex differences are partly innate
Why upbringing has less impact than we think - but it’s also not all in the genes
The nature and nurture of criminality and addiction
How a better understanding of human nature can help us build a better world

Despite coming at these issues from very different philosophical starting points, Joseph and I found a great deal of common ground on human nature, morality, and how best to cultivate our better angels while restraining our darker impulses.

The episode is available on Apple Podcasts, Spotify, Podbean, and wherever else you listen to podcasts.

Follow me on Twitter/X for more psychology, evolution, and science.

From the Archive

How You Can Support the Newsletter

If you like what I’m doing with The Nature-Nurture-Nietzsche Newsletter and want to support my work, there are several ways you can do it.

Like and Restack - Click the buttons at the top or bottom the page to boost the post’s visibility on Substack.
Share - Send the post to friends or share it on social media.

Upgrade to Paid - A paid subscription gets you:
- Full access to all new posts and the archive
- Full access to exclusive content such as my “12 Things Everyone Should Know” posts, Linkfests, and other regular features
- The ability to post comments and engage with the growing N³ Newsletter community

If you could do any of the above, it’d be much appreciated. The support of readers like you helps keep the newsletter going.

Thanks!

Steve

Can You Control Your Own Beliefs?

Turi Munthe — Wed, 27 May 2026 11:42:49 GMT

This is a guest post by Turi Munthe. His book, Why We Think What We Think: The Unexpected Origins of Our Deepest Beliefs, was published on May 14 by Penguin’s Hutchinson Heinemann.

Can You Control Your Own Beliefs?

Only if you know how your beliefs control you.

A few years ago, the UK’s Guardian newspaper bravely informed its left-leaning readership that attractive people tended to lean right. The heartthrobs and dreamboats of this world - people with conventionally desirable traits like tall men and women, men with high natural upper-body strength and women with symmetrical faces - vote conservative. Specifically, attractive people are greater believers in meritocracy - the classic conservative view that you should earn what you get, and that you get what you deserve.

There’s nothing intrinsically sexy about conservatism: listening to Ronald Reagan’s speeches will not give you lustrous hair or an aquiline nose. The reason that conventionally attractive people tend, on average, to be bigger believers in meritocracy is because of something teenagers call ‘Pretty Privilege’. Beautiful people inhabit a gentler reality than us common mortals: strangers, teachers, employers and even parents all bend towards them, quietly smoothing their path. It’s no wonder they trust in a meritocracy - for them, it largely works, even if their ‘merit’ is only being pretty.

It’s a disconcerting notion. Who wants to be told their careful reading of Milton Friedman and Friedrich Hayek is just post-hoc rationalisation? That their deepest convictions are arbitrary: the fruit of happenstance rather than intellectual agency?

And yet, as I show in Why We Think What We Think: The Unexpected Origins of Our Deepest Beliefs, so many of our opinions are just that. From our faith in God to our taste in decoration, the ‘reasons’ we hold our convictions are often more accurately attributable to quirks of history, geography, climate, psychology and even genetics than to reading, deliberation and ‘reasoning’.

Wherever the climate is hot and humid - from Singapore to the DRC - people tend to be both more xenophobic and more conformist than the global average. Why? Because hot and humid climates are rich in pathogens like bacteria, fungi and parasites. The locals’ wariness of strangers comes from a heightened fear they might bring infection. And their learned conformity is a form of behavioural immunity to ensure nobody deviates from the practices they know will keep them safe from contagion.

People who score high in ‘neuroticism’ (one of our five key personality traits) are more likely to follow radical ideologies. At the 2015 general election, they were both more likely to vote for the hard-left Greens and more likely to vote for the hard-right UK Independence Party. Why? Because that existential discomfort prompts those high in neuroticism to search for radical alternatives that might fix it.

‘Moralising’ deities like God or Allah (and unlike, say, Zeus or Thor who don’t have much to moralise about given their own behaviour) almost always emerge in regions prone to drought. Why? Because drought is the great climatic killer - worse than floods or typhoons or earthquakes - and the only way to survive it as a society is to pull together. You need strict moral rules to keep the community from destroying itself - they’re less important when everyone is doing OK.

Your deepest sense of self and your relationship to the world is a by-product of the agriculture of your ancestors. There are two broad camps. Individualist cultures (like Europe) prioritise self-expression and personal autonomy over group loyalty, and collectivist ones (like Asia) prioritise shared obligations and social harmony over personal interests. If your ancestors grew up planting wheat, you’re likely the former, and if rice, then the latter. Why? Because rice cultivation takes whole communities to build the paddies, manage the irrigation systems and harvest the rice. A culture of cooperation and harmony was essential to survival. Whereas wheat can be cultivated by a single family, which afforded early Europeans the luxury of putting themselves first.

We know our beliefs are subject to the vagaries of history: 500 years ago, we’d all have believed the sun rotated around the Earth. But history influences our attitudes in much more unconscious ways too. Why are Bretons historically more liberal, less patriarchal and more egalitarian than their neighbouring Frenchmen? Because, as Asterix tells us, the Romans never truly conquered that corner of the country, and the paternalistic culture Rome spread across Europe never took root quite so deeply there.

There are countless ‘accidental’ environmental influences on our opinions - like the weather, or topography, or history - but there are also deeper ‘biological’ ones too, and they have an outsized effect on our politics.

Right-wingers, on average, have measurably more taste buds than left-wingers. It’s because people with greater ‘disgust sensitivity’ (like sensitive tongues) tend to be more conservative in all their tastes, and more judgmental of those who deviate from them.

Put a teenager in a brain scan and you can tell with 70% probability what their politics are. The amygdala, which responds to emotions like fear and threat, tends to be larger and more active in conservative teens; the prefrontal cortex, which processes ambiguous information and works to resolve cognitive conflict, is more active in liberal ones. That enlarged amygdala might be behind right-wing concerns about immigration or crime. And that overactive prefrontal cortex might explain why liberals tend to be more tolerant of difference or why so many pernickety academics lean left.

Your politics owe more to your genes than to your reading. Identical twins who share 100% of their DNA have MUCH more similar politics than fraternal twins who share only 50% of their DNA, even when they were raised apart. By comparing identical and fraternal twins’ beliefs, we know that genetics explains around 50% of the variance in our views on tax policy (or porn), for example. That means that half of the differences between people’s opinions on things like government spending (or banning Pornhub) can be traced back to their genes – inherited traits from their biological parents.

Our opinions are not predetermined: we can control our beliefs. Some cuties do vote Labour, just as some trolls vote conservative. We are, as the famous phrase goes, hardwired not to be hardwired. Humans have the most extraordinary capacity for reason. We do have intellectual agency. We can and frequently do change our minds. But we are predisposed to many of our beliefs. Acknowledging that, and understanding how the quirks of history, geography, climate, psychology and even biology unconsciously influence our worldviews is the first step towards achieving intellectual independence from ourselves.

Turi Munthe is the author of Why We Think What We Think: The Unexpected Origins of Our Deepest Beliefs, which was published 14 May with Penguin’s Hutchinson Heinemann.

How You Can Support the Newsletter

This guest post was free to read for all. If you like what I’m doing with The Nature-Nurture-Nietzsche Newsletter, and want to support my work, there are several ways you can do it.

Like and Restack: Click the buttons at the top or bottom of the page to boost the post’s visibility on Substack.
Share: Send the post to friends or share it on social media.

Upgrade to Paid: A paid subscription gets you:
- Full access to all new posts and the archive
- Full access to excerpts from my forthcoming book A Billion Years of Sex Differences
- Full access to exclusive content such as my “12 Things Everyone Should Know” posts, Linkfests, and other regular features
- The ability to post comments and engage with the growing N³ Newsletter community

If you could do any of the above, I’d be hugely grateful. The support of readers like you helps keep this newsletter going and growing.

Thanks!

Steve Stewart-Williams

Second Review of A Billion Years of Sex Differences!

Steve Stewart-Williams — Tue, 26 May 2026 09:25:14 GMT

Credit: Iris Images/Getty Images

The second review of A Billion Years of Sex Differences just dropped!

This one’s by Sophie McBain in The Guardian. The Guardian tends to lean progressive, so I had wondered how the book would be received. But it’s a very thoughtful review, and a very positive one overall.

The opening paragraph summarizes the book nicely:

According to the evolutionary psychologist Steve Stewart-Williams, almost everyone gets sex wrong. Traditionalists tend to exaggerate the natural differences between men and women. Progressives tend to minimise them, and to assume that nurture and socialisation play a decisive role. He wants to promote a more nuanced, scientifically rigorous public conversation about why and how men and women differ to guide better policymaking.

McBain adds that the “book is filled with interesting, counterintuitive findings, studies you might want to discuss with a friend.”

There are some parts of the review that I’d quibble with and that I think McBain gets wrong. For example, she claims I don’t discuss our history of anti-female bias, but I do. And she suggests that it’s rather convenient to focus on innate influences rather than the structure of the workplace, when I argue we should focus on both.

But none of her criticisms are particularly unreasonable or unfair, and my overall impression is that she’s sincerely engaged with ideas that are outside her comfort zone. Who could ask for more?

You can read the whole review here or here (Spanish-language version). And if you’d like a copy of the book, you can order it from the Guardian Bookshop at a discount.

Follow me on Twitter/X for more psychology, evolution, and science.

Upgrade to a Paid Subscription

Thanks!

Steve

Sex Differences in Sexual Choosiness

Steve Stewart-Williams — Sat, 23 May 2026 16:13:45 GMT