I don’t want to write much more about this issue, but since we’ve been discussing the binary nature of human sex (or non-binary, if you oppose that view), I thought I’d call to your attention two items.
The first is a piece by a strong defender of the sex binary, Colin Wright, in which he republishes his first article on the topic (Quillette, 2018), and updates it. The second is physicist Sean Carroll’s new video discussing and explaining his controversial tweet implying that sex is not binary, but a spectrum. We’ll take them in order.
The new piece by Colin Wright at his Substack site (Reality’s Last Stand) is really the republication of his 2018 Quillette paper (“The new evolution deniers“), with an introduction to cover the last four years. Wright was on the track to be an academic at the time, but the Quillette article, which received a bunch of pushback, combined with other articles he wrote, including an op-ed with Emma Hilton in the Wall Street Journal, made him un-hireable and so he had to leave academia. He more or less predicts that at the end of his 2018 paper.
Colin’s first article is about the binary nature of sex and about those who deny it for ideological reasons. As you know, I agree with Wright that sex is effectively a binary, or at least with this statement that he made in that article:
. . . the final result of sex development in humans are unambiguously male or female over 99.98 percent of the time. Thus, the claim that “2 sexes is overly simplistic” is misleading, because intersex conditions correspond to less than 0.02 percent of all births, and intersex people are not a third sex. Intersex is simply a catch-all category for sex ambiguity and/or a mismatch between sex genotype and phenotype, regardless of its etiology. Furthermore, the claim that “sex is a spectrum” is also misleading, as a spectrum implies a continuous distribution, and maybe even an amodal one (one in which no specific outcome is more likely than others). Biological sex in humans, however, is clear-cut over 99.98 percent of the time. Lastly, the claim that classifying people’s sex based on anatomy and genetics “has no basis in science” has itself no basis in reality, as any method exhibiting a predictive accuracy of over 99.98 percent would place it among the most precise methods in all the life sciences. We revise medical care practices and change world economic plans on far lower confidence than that.
If you haven’t read the Quillette piece, you can do so as it’s embedded in the update below; click to read
Wright recounts the genesis of his article, which was his realization that the binary nature of biological sex was under attack, and that, like creationism, this was a denial of scientific fact, though coming from the Left rather than the Right. He argues in the update above that he was motivated only by a concern for biological truth and not to attack “gender ideology”:
One thing you may notice is that The New Evolution Deniers doesn’t mention gender ideology at all. That’s because I came to the gender debate believing that people were simply wrong about biology, and that if I could clearly articulate exactly why, I would change people’s minds. It wasn’t until later, after looking under the hood to see where modern sex denialism was coming from, that I realized this wasn’t a matter of ignorance, but a result of highly motivated reasoning. It wasn’t about true or false to them, it was about good versus evil.
Although I’m on Colin’s side vis-à-vis the biological facts, as well as about the ideological nature of opposition, in fact if he doesn’t “mention gender ideology in the original piece”, he certainly alludes to it very heavily. For example:
Even more recently, the most prestigious scientific journal in the world, Nature, published an editorial claiming that classifying people’s sex “on the basis of anatomy or genetics should be abandoned” and “has no basis in science” and that “the research and medical community now sees sex as more complex than male and female.” In the Nature article, the motive is stated clearly enough: acknowledging the reality of biological sex will “undermine efforts to reduce discrimination against transgender people and those who do not fall into the binary categories of male or female.” But while there is evidence for the fluidity of sex in many organisms, this is simply not the case in humans. We can acknowledge the existence of very rare cases in humans where sex is ambiguous, but this does not negate the reality that sex in humans is functionally binary. These editorials are nothing more than a form of politically motivated, scientific sophistry.
. . . Despite the unquestionable reality of biological sex in humans, social justice and trans activists continue to push this belief, and respond with outrage when challenged. Pointing out any of the above facts is now considered synonymous with transphobia. The massive social media website Twitter—the central hub for cultural discourse and debate—is now actively banning users for stating true facts about basic human biology. And biologists like myself often sit quietly, afraid to defend our own field out of fear that our decade of education followed by continued research, job searches, and the quest for tenure might be made obsolete overnight if the mob decides to target one of us for speaking up. Because of this, our objections take place almost entirely between one another in private whisper networks, despite the fact that a majority of biologists are extremely troubled by these attacks to our field by social justice activists. This is an untenable situation.
If that’s not mentioning gender ideology, I don’t know what is! It’s hard to believe that someone could write about the controversy without mentioning why it exists, and Colin certainly does that. I don’t see an issue with his take on why the controversy arose—and I agree that it’s a dispute over ideology, not biological fact. But I do take issue with his new claim that he doesn’t mention gender ideology. Still, that’s really a quibble. The fact is that although Wright has left academia, he’s still fighting to make people realize the biological facts about sex, but is now also fighting ideologues who claim that he’s a transphobe.
He’s not. If you read his original piece in Quillette, you will find this:
It is undoubtedly true that trans people lead very difficult lives, which are only made more difficult by the bigotry of others. But social justice activists appear completely unwilling or unable to distinguish between people who criticize their ideology and people who question their humanity. Their social immune system appears so sensitive that it consumes itself. We need to acknowledge that trans issues and ideology are complex, and concern one of the most marginalized communities in the world. Because of this, we must give these issues the respect they deserve by approaching them with nuance and compassion instead of crudeness and cruelty. But we must not jettison truth in this process. If social justice activists require scientists to reject evolution and the reality of biological sex to be considered good allies, then we can never be good allies.
I would add in the first sentence “unwilling or unable to distinguish between people who criticize their ideology and people who question their humanity and the facts of biology.”
So much for Dr. Wright, who describes the biological fact accurately. Now onto Sean Carroll, who started a mini-fracas on Twitter when he made the tweet below, criticizing Wright’s correct claim that “biological sex is real, immutable, and binary”, and then putting up a misleading graph from Scientific American implying that biological sex is a spectrum. The figure even shows a spectrum of colors. It isn’t rocket science to see that Sean appeared to agree with the Scientific American stand.
— Sean Carroll (@seanmcarroll) November 14, 2022
I tweeted back defending the same biological issues that concerned Wright.
"Actual science" done by biologists shows 2 sexes, one with small mobile gametes and the other with large, immobile ones. There is no third sex. Disorders of sex development are not new sexes, and biological sex is binary. Let's not conflate sex, gender & developmental anomalies. https://t.co/tANXZM5S0r
— Jerry Coyne (@Evolutionistrue) November 14, 2022
And several other people, including responders to Sean’s Tweet, as well as Wright, Steven Knight, and Manchester Uni biologist Emma Hilton, criticized Sean’s view as well (see my post about that here). Sean has responded on a video from his Mindscape series, and in the interest of fairness I’ll present his discussion of sex and of the tweet above. You can hear the discussion at the beginning of the podcast below. The bit about sex, the binary, and the tweet go from 05:29 to 25:30.
To his credit, Sean begins by apologizing for that tweet, which he says was “snarky, dismissive, and lowers the tone of the debate.” You have to admire him for that—how many people would admit it and apologize?
He then elaborates on what his tweet was trying to say, which boils down to the idea that “human sexuality is complicated.” There’s a complicated developmental pathway that yields gametes and other traits associated with sex, chromosomes play a role, and there are other “secondary sexual characteristics”, like voice timbre and body hair, associated with sex. Further, he notes that “there are psychological, sociological, cultural and political aspects of sex,” which includes gender, your rights, how you’re treated by others, and so on. He says that there are issues beyond the biological ones, including philosophical and language issues, and he expatiates on those issues, evincing—and I agree—an empathy for those who are neither biologically male or female, as well as transsexual people.
I won’t go into that, for you can listen for yourself. All I’ll say is what I was trying to say in the first place: biologically speaking, sex is as close to a binary as you can get. And yes, like all developmental processes, it’s complicated. The sex binary is opposed or even denied by a lot of people, but the denial is largely motivated by ideology. The dispute does not come from a quarrel among biologists.
I’ll add as Sean emphasizes, that we often use “sex” in a looser manner, since we can’t see people’s gametes. That’s the difference between defining sex and recognizing it. Things become messier when you try to define sex using traits, like genitalia, that some people use to recognize sex.
Finally, of course I agree with Sean that “we should give all human beings equal dignity”. I believe I’ve made that point repeatedly when I write about the sex binary. I care more about the binary than he does simply because I am a biologist, because this issue involves evolution, and because I care about whether the facts of biology are presented accurately to people. Finally, I care that that biology remains, as far as humanly possible, free from intrusion by ideology.