When I read people talk about the etiology of transness– particularly, but not solely, discussion of the Blanchard/Bailey theory of trans women– I often see a response from cis people that’s along the lines of “Who cares? If you want to transition, I think you should transition. I don’t care whether it’s a fetish or caused by gender-non-conformity or whatever; as long as it makes you happy, it’s fine. You have the right to make decisions about your own body.”

To be clear, this is a really good attitude for people to have! In fact, I think it’s the correct attitude to have about other people’s transitions. It’s really none of your business what people decide to do with their own personal bodies: getting a tattoo, getting cosmetic surgery, not getting cosmetic surgery, or transitioning. Even if Anne Lawrence is a completely and 100% accurate reporter of her own internal experience, I support her right to transition.

But it also matters what’s true.

Even if information about the etiology of transness doesn’t (and shouldn’t!) affect the behavior of cis people, it sure as hell should affect the behavior of trans and gender-questioning people. Transition is a big step; reversing it can be embarrassing (“uh, actually, turns out I’m a girl, sorry about that”), difficult (“welp, time to save up money for my boob job”), or impossible (“I’m never going to be able to get pregnant”). A lot of signs that one might be trans– depression, dissociation, a strong desire to wear clothing associated with a particular gender, glee when you pass– can also be caused by a lot of other things. Right now, really the only way to figure out whether transition is a good idea is trying it and seeing if you like it. If we understood why people are trans, it could provide gender-questioning people more guidance in figuring out whether transition is right for them.

For instance, let’s say that God comes down from on high and says “yep, the Blanchard/Bailey theory of transness is absolutely and 100% accurate, this is definitely how transness works.” In that case, a lot of very feminine gay men and straight men who jerk off to sissification porn should consider transitioning, even if they have no particular desire to be women– empirically, people who are quite similar to them seem to have found transitioning to be the correct choice. Conversely, assigned-male-at-birth people who aren’t solely attracted to men and who find that crossdressing porn leaves them cold should probably not transition: it’s very likely that their condition is actually depression, a dissociative disorder, or similar.

On the other hand, if God comes down from on high and says “actually, gender dysphoria is a neurological intersex condition, and you can identify it through looking at the differences in these six brain regions”, suddenly it becomes very important to get a brain scan before you consider transitioning.

If God says “gender dysphoria is a lifelong condition and if you didn’t have gender dysphoria before puberty you don’t have it now”, it is ill-advised for me to transition. If God says “gender dysphoria in children is linked to but distinct from gender dysphoria in adults, and gender dysphoric children often grow up to be adults without gender dysphoria”, it is ill-advised to put your gender-dysphoric eleven-year-old on HRT.

To be clear, I support the right of any person who wishes to transition to do so (although perhaps not to have their transition covered by insurance). If we knew that transness was a neurological intersex condition, I would support the right of people without that condition to transition; if we knew that the Blanchard/Bailey theory was correct, I would support the right of masculine people without a sexual fetish for being a woman to transition. But that doesn’t mean their decision would be a good one, and people– naturally– want to make good decisions about such an important issue. So the etiology of transness does matter.