+Indeed—here we are six years later, and _I am panicking_. (As 2007–9 Sequences-era Yudkowsky [taught me](https://www.yudkowsky.net/other/fiction/the-sword-of-good), and 2016 Facebook-shitposting-era Yudkowsky seemed to ignore, the thing that makes a moral panic _really_ interesting is how hard it is to know you're on the right side of it—and the importance of [panicking](https://www.lesswrong.com/posts/erGipespbbzdG5zYb/the-third-alternative) [sideways](https://www.overcomingbias.com/2007/05/policy_tugowar.html) when the "maximize the number of trans people" and "minimize the number of trans people" coalitions are both wrong.)
+
+But at the time, this was merely _very confusing_. I left [a careful comment in the Facebook thread](/images/facebook_etle_comment.png) (with the obligatory "speaking only for myself; I obviously know that I can't say anything about anyone else's experience" [disclaimer](https://www.overcomingbias.com/2008/06/against-disclai.html)), quietly puzzled at what Yudkowsky could _possibly_ be thinking ...
+
+A month later, I moved out of my mom's house in [Walnut Creek](https://en.wikipedia.org/wiki/Walnut_Creek,_California) to go live with a new roommate in an apartment on the correct side of the [Caldecott tunnel](https://en.wikipedia.org/wiki/Caldecott_Tunnel), in [Berkeley](https://en.wikipedia.org/wiki/Berkeley,_California): closer to other people in the robot-cult scene and with a shorter train ride to my coding dayjob in San Francisco.
+
+(I would later change my mind about which side of the tunnel is the correct one.)
+
+In Berkeley, I met some really interesting people who seemed quite similar to me along a lot of dimensions, but also very different along some other dimensions having to do with how they were currently living their life! (I see where the pattern-matching faculties in Yudkowsky's brain got that 20% figure from.) This prompted me to do a little bit more reading in some corners of the literature that I had certainly _heard of_, but hadn't already mastered and taken seriously in the previous twelve years of reading everything I could about sex and gender and transgender and feminism and evopsych. (Kay Brown's blog, [_On the Science of Changing Sex_](https://sillyolme.wordpress.com/), was especially helpful.)
+
+Between the reading, and a series of increasingly frustrating private conversations, I gradually became increasingly persuaded that Blanchard _wasn't_ dumb and wrong, that his taxonomy of male-to-female transsexualism is _basically_ correct, at least as a first approximation. So far this story has just been about _my_ experience, and not anyone's theory of transsexualism (which I had assumed for years couldn't possibly apply to me), so let me take a moment to explain the theory now.
+
+(With the caveated understanding that psychology is complicated and there's more to be said about what "as a first approximation" is even supposed to mean, but I need a few paragraphs to talk about the _simple_ version of the theory that makes _pretty good_ predictions on _average_, before I can elaborate on more complicated theories that might make even better predictions including on cases that diverge from average.)
+
+The idea is that male-to-female transsexualism isn't actually one phenomenon; it's two completely different phenomena that don't actually have anything to do with each other, except for the (perhaps) indicated treatment of HRT, surgery, and social transition. (Compare to how different medical conditions might happen to respond to the same drug.)
+
+In one taxon, the "early-onset" type, you have same-sex-attracted males who have just been extremely feminine (in social behavior, interests, _&c._) their entire lives, in a way that causes huge social problems for them—the far tail of effeminate gay men who end up fitting into Society better as straight women. _That's_ where the "woman trapped inside a man's body" trope comes from. [This one probably _is_ a brain-intersex condition.](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3180619/)
+
+That story is pretty intuitive. Were an alien AI to be informed of the fact that, among humans, some fraction of males elect to undergo medical interventions to resememble females and aspire to be perceived as females socially, "brain-intersex condition such that they already behave like females" would probably be its top hypothesis for the cause of such behavior, just on priors.
+
+Suppose our alien AI were to be informed that many of the human males seeking to become female (as far as the technology can manage) do _not_ fit the clinical profile of the early-onset type—it looks like there's a separate "late-onset" type or types. If you [didn't have enough data to _prove_ anything, but you had to guess](https://www.lesswrong.com/posts/xTyuQ3cgsPjifr7oj/faster-than-science), what would be your _second_ hypothesis for how this behavior might arise?
+
+What's the _usual_ reason for males to be obsessed with female bodies?
+
+So, yeah. Basically, I think a _substantial majority_ of trans women under modern conditions in Western countries are, essentially, guys like me who were _less self-aware about what the thing actually is_.
+
+So, I realize this is an inflamatory and (far more importantly) _surprising_ claim. Obviously, I don't have introspective access into other people's minds. If someone claims to have an internal sense of her own gender that doesn't match her assigned sex at birth, on what evidence could I _possibly_ have the _astounding_ arrogance to reply, "No, I think you're really just a perverted male like me"?
+
+Actually, lots. To arbitrarily pick one particularly vivid exhibit, in April 2018, the [/r/MtF subreddit](https://www.reddit.com/r/MtF/) (which currently has 100,000 subscribers) [posted a link to a poll: "Did you have a gender/body swap/transformation "fetish" (or similar) before you realised you were trans?"](https://archive.is/uswsz). The [results](https://strawpoll.com/5p7y96x2/r): [_82%_ said Yes](/images/did_you_have-reddit_poll.png). [Top comment in the thread](https://archive.is/c7YFG), with over 230 karma: "I spent a long time in the 'it's probably just a fetish' camp".
+
+Certainly, 82% is not 100%! (But 82% is evidence for my claim that a _substantial majority_ of trans women under modern conditions in Western countries are essentially guys like me.) Certainly, you could argue that Reddit has a sampling bias such that poll results and karma scores from /r/MtF fail to match the distribution of opinion among real-world MtFs. But if you don't take the gender-identity story as a _axiom_ and [_actually look_](https://www.lesswrong.com/posts/SA79JMXKWke32A3hG/original-seeing) at the _details_ of what people say and do, these kinds of observations are _not hard to find_. You could [fill an entire subreddit with them](https://archive.is/ezENv) (and then move it to [independent](https://ovarit.com/o/ItsAFetish/) [platforms](https://saidit.net/s/itsafetish/) when the original gets [banned for "promoting hate"](https://www.reddit.com/r/itsafetish/)).