+Another factor affecting the degree to which trans people form a more natural category with their identified gender than their natal physiological sex is the nature of transgenderedness itself. If gender dysphoria is caused by a brain-restricted intersex condition, such that trans people's psychology is much more typical of the other physiological sex—if the "woman trapped in a man's body" trope is basically accurate—that would tend to weigh in favor of accepting transgender identity claims: trans women would be "coming from the same place" as cis women in a very literal psychological sense, despite their natal physiology.
+
+On the other hand, if gender dysphoria is caused by something else, that would tend to weigh against accepting transgender identity claims: however strongly felt trans people's _subjective_ sense of gender identity might be, if the mechanism underlying that feeling actually has nothing in particular in common with anything people of the identified-with sex feel, it becomes relatively more tempting to classify the subjective sense of gender identity as an illusion, rather than the joint in reality around which everyone needs to carve their gender categories.
+
+Of course, the phrasing _If gender dysphoria is caused by ..._ implies that we're considering _gender dysphoria_ as one category to reason about homogenously. But different people might want to transition for very different underlying psychological reasons. What categories we use may not be a question of simple fact that we can get wrong, but if, empirically, there happens to be a sufficiently robust statistical structure to the simple facts of the cases—if some people want to transition for reason _A_ and tend to have traits _W_ and _X_, but others want to transition for reason _B_ and have traits _Y_ and _Z_—then aspiring epistemic rationalists may find it useful to distinguish multiple, distinct psychological conditions that all happen to cause gender dysphoria as a symptom.
+
+Analogously, in medicine, many different pathogens can cause the same symptoms (_e.g._, coughing and sneezing), but doctors care about distinguishing different illnesses by etiology, not just symptoms, because distinct physical mechanisms give rise to distinct treatment decisions, if not immediately (_e.g._, because a bacterial illness will respond to antibiotics, but a viral one won't) then at least in principle (_e.g._, today's treatments might be equally effective against two different species of bacteria, but future drugs might work better on one or the other).
+
+_As it happens_, (I claim) the evidence that gender dysphoria is more than one thing is quite stong. For reasons of personal interest, I'm going to focus on the male-to-female case for the rest of this post. (An analysis of the female-to-male situation would be similar in many respects but different in others, and is left to the interested reader.)
+
+[explain the taxonomy, point out that it's possible to believe in a weaker version of it; link to Lawrence, &c.]
+
+In less tolerant places and decades, where MtF transsexuals were very rare and had to try very hard to pass as (cis) women out of dire necessity, their impact on the social order and how people think about gender was minimal—there were just too few trans people to make much of a difference. This is why experienced crossdressers often report it being easier to pass in rural or suburban areas rather than cities with a larger LGBT presence—not as a matter of tolerant social attitudes, but as a matter of _base rates_: it's harder to get [clocked](https://www.urbandictionary.com/define.php?term=clocked&defid=4884301) by people who aren't aware that being trans is even a thing. (In [predictive processing](http://slatestarcodex.com/2017/09/05/book-review-surfing-uncertainty/) terms: the prediction errors caused by observations of a trans woman failing to match the observer's generative model of (cis) women get silenced for lack of alternative hypotheses if "She's trans" isn't in the observer's hypothesis space.)
+
+Nowadays, in progressive enclaves of Western countries, transness is definitely known to be a thing—and in particular subcultures that form around [non-sex-balanced interests](http://slatestarcodex.com/2017/08/07/contra-grant-on-exaggerated-differences/), the numbers can be quite dramatic. For example, on the [2018 _Slate Star Codex_ reader survey](http://slatestarcodex.com/2018/01/03/ssc-survey-results-2018/), 9.4% of respondents selected _F (cisgender)_ for the gender question, compared to 1.4% of respondents selecting _F (transgender m -> f)_. So, if trans women are women, _13.4%_ (!!) of women who read _Slate Star Codex_ are trans.
+
+I can't say this causes any problems, because that would depend on how you choose to draw the category boundaries around what constitutes a "problem." But objectively, injecting a substantial fraction of otherwise-ordinary-but-for-their-gender-dysphoria natal males into spaces, roles, and categories that developed around the distribution of psychologies of natal females _is_ going to have _some_ sort of nontrivial consequences (whether you judge those consequences to be good or bad).
+
+A (cis) female friend of the blog, a member of a very ["Blue Tribe"](http://slatestarcodex.com/2014/09/30/i-can-tolerate-anything-except-the-outgroup/) city's rationalist community (that is, basically the same group of people generating the _Slate Star Codex_ survey results just mentioned) reports on recent changes in local social norms—
+
+> There have been "all women" things, like clothing swaps or groups, that then pre-transitioned trans women show up to. And it's hard, because it's weird and uncomfortable once three or four participants of twelve are trans women. I think the reality that's happening is women are having those spaces less—instead doing private things "for friends," with specific invite lists that are implicitly understood not to include men or trans women. This sucks because then we can't include women who aren't _already_ in our social circle, and we all know it but no one wants to say it.
+
+But this is a _terrible_ outcome with respect to _everyone's_ values. One can't even say, "Well, the cost to those bigoted cis women of not being able to have trans-exclusionary spaces is more than outweighed by trans women's identities being respected," because the non-passing trans women's identities aren't being respected _anyway_; it's just that (cis) women are collectively too _nice_ to [make it common knowledge](http://slatestarcodex.com/2015/10/15/it-was-you-who-made-my-blue-eyes-blue/). (The sex difference in [Big Five](https://en.wikipedia.org/wiki/Big_Five_personality_traits) Agreeableness is [_d_](https://en.wikiversity.org/wiki/Cohen%27s_d)=0.48.)
+
+-----
+
+People should get what they want. We should have social norms that help people get what they want. Unfortunately, helping people get the things that they want is a hard problem, because people are complicated and the world is complicated. That's why, when renegotiating social norms to apply to a historically unprecedented situation,
+
+As a transhumanist as and as an individualist, I want to protect people's freedom to modify their body and social presentation, which _implies_ the right to transition. For the same reasons, I want to protect people's freedom of association, which _implies_ the right to transition.