> For most transgender people, we can’t point to any specific neurobiological factor as an explanation for why they are transgender. And even for the minority for whom there is something specific to point to, there will be other people who share that factor yet aren’t transgender, so that factor can’t be a complete explanation-and the rest of the explanation we just don’t know. All I think we can confidently say is that biological factors are in the mix, but we can’t rule out the possibility that psychosocial/sociocultural/etc factors also have some role to play-plus, the respective contributions of the biological vs the non-biological may differ from person to person.

I was careful to word that as "as reflected in internal psychology". I don't think we're going to pinpoint any specific pieces of brain wiring any time soon, but there are quite clearly profound internal psychological differences -- since supernatural phenomena don't exist, they must be either due to internal brain wiring or another property of the internal body, or due to social factors, or a mix of both.

A survey I've done of trans people near me is whether they'd still want to transition on a desert island. Some say no, but the vast majority say yes. To me, this demonstrates that there's at least some inherent characteristic at play.

> Also, I don’t know if everyone actually has a “gender identity”. I mean, I don’t think I do. Yes, I have XY chromosomes with a typical male phenotype, a male-coded given name, my legal documents all say M, I’m married to a woman and father of two children with her, and I suppose “male” describes a social role I play. But, I don’t have some internal “identity” as “male”. Maybe this is an autistic trait, but deep down inside I don’t identify as anything at all. Well, maybe as pure consciousness, and everything else about me (including my sex/gender) is just a contingent chance accident of what that consciousness happens to experience.

Strength of internal gender identity does vary -- agender people demonstrate that. But would you be able to transition (especially medically) and live day in and day out as a woman?

Dr Will Powers, a cis male, has a description of how taking an excessive dose of estrogen gave him gender dysphoria for days [1].

David Reimer, another cis male, was forcibly transitioned by his doctor after a botched surgery as an infant [2]. He suffered lifelong dysphoria as a result, and tragically took his own life at a young age.

What trans people go through is quite similar to what these people went through, just in reverse. Reimer was lied to about his gender for years, which led to tremendous distress. Trans people are falsely informed (though not as a lie since this isn't intentional at first) about their gender for years, which also leads to tremendous distress. A lot of people want to openly and proudly lie about it, in a way that is documented to cause distress.

> Do non-trans people have gender dysphoria when they are misgendered? Some of them don’t really care. And even if a person reacts negatively, is that due to gender dysphoria? Or could it be they feel upset because you’ve got a fact about them wrong, and they might be just as upset if you’d got any other fact wrong instead? And even if they experience some special upset at being misgendered, how do we know that isn’t just due to cultural conditioning, as opposed to an innate psychological factor?

Gender culture is created primarily by cis/het people, so it's hard to separate the two out. Being upset at misgendering is a cross-cultural phenomenon -- I've asked cis people across American, European and a couple different Asian cultures about this.

> The problem I see: I think there’s often a substantial gap between what the science actually says, and what people claim the science says (including even many scientists themselves, especially when addressing a lay audience.) I think when you look at the actual research, it is obvious that there are still massive gaps in our knowledge, along with widespread problems with replication, methodology, sample sizes, etc. It is obvious that biology has a significant role to play in issues of gender and sexuality-but saying much more than that involves rather high epistemic uncertainty.

To be clear, we don't actually need to know the causes of some people being trans. There is a vast amount of scientific evidence regarding the efficacy of gender-affirming care (astonishingly low regret rates!) [3], and anthropological evidence that every society with a recorded history has had some notion of gender variance [4]. It also tracks with my own experience transitioning after spending years detached from my body [5].

> Yet a lot of the public discourse on this topic makes the scientific picture sound a lot firmer than it actually is. And I think many scientists think it is more important to publicly present the science as clearly supporting a progressive social agenda, than be completely open and honest about just how much we still don’t know, and how patchy the evidence actually is for some of the conclusions they endorse

What specific conclusions is the evidence patchy for, in a way that distinguishes GAC specifically? The evidence is often observational rather than RCT, but that's because RCTs are impossible when changes are visible within days. There is less evidence for pediatric care than for adult care, but extrapolating from adult to pediatric care is very common across all of medicine. (Some reports like the one by Cass claim otherwise, but they have a number of shockingly incorrect statements which indicate a lack of basic familiarity with the field [6].) The evidence is often based on self-reporting, but that's true for many other interventions as well, like when I fill out a DASS-21.

[1] https://www.reddit.com/r/DrWillPowers/comments/fcxboa/the_st.... (This is not an endorsement of the doctor, who has a number of problematic practices. But it's an amusing and enlightening story.)

[2] https://en.wikipedia.org/wiki/David_Reimer

[3] https://old.reddit.com/r/asktransgender/comments/154t1qq/my_...

[4] Again, not an endorsement of the particular gender structures of each society -- many of them forcibly third-gendered all trans people, which is a kind of misgendering like any other.

[5] My experiences before transitioning were remarkably similar to https://www.mayoclinic.org/diseases-conditions/depersonaliza... -- I used to joke all the time about it. This is not something I feel any longer.

[6] https://cass.independent-review.uk/wp-content/uploads/2024/0... -- for example, p. 14 has the statement "medication is binary", which is plainly false. There are several ways to medically transition in a non-binary manner, and every doctor in the field knows about them. The fact that a statement like this made it all the way to publication calls into question the basic competence of the people involved. The statement is quite material as well, since it essentially makes the argument that nonbinary people may not want to medically transition. Maybe, but certainly not based on the false idea that medical transition is binary.