-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 people of the identified-with sex, it becomes 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.
+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 both 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, either immediately (_e.g._, a bacterial illness will respond to antibiotics, but a viral one won't) or 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 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 report it being easier to pass in rural areas rather than
+