+The argument goes: it might be easy to _imagine_ changing sex and refer to the idea in a short English sentence, but the real physical world has implementation details, and the implementation details aren't filled in by the short English sentence. The human body, including the brain, is an enormously complex integrated organism; there's no [plug-and-play](https://en.wikipedia.org/wiki/Plug_and_play) architecture by which you can just swap your brain into a new body and have everything Just Work without re-mapping the connections in your motor cortex. And even that's not _really_ a sex change, as far as the whole integrated system is concerned—
+
+[TODO: include more blockquote here]
+
+> Remapping the connections from the remapped somatic areas to the pleasure center will ... give you a vagina-shaped penis, more or less. That doesn't make you a woman. You'd still be attracted to girls, and no, that would not make you a lesbian; it would make you a normal, masculine man wearing a female body like a suit of clothing.
+
+But, well ... I mean, um ...
+
+(I still really don't want to be blogging about this, but _somebody has to and no one else will_)
+
+From the standpoint of my secret erotic fantasy, "normal, masculine man wearing a female body like a suit of clothing" is actually a _great_ outcome—the _ideal_ outcome. Let me explain.
+
+The main plot of my secret erotic fantasy accomodates many frame stories, but I tend to prefer those that invoke the [literary genre of science](https://www.lesswrong.com/posts/4Bwr6s9dofvqPWakn/science-as-attire), and posit "technology" rather than "spells" or "potions" as the agent of change, even if it's all ultimately magic (where "magic" is anything you don't understand).
+
+So imagine having something like [the transporter in _Star Trek_](https://memory-alpha.fandom.com/wiki/Transporter), but you re-materialize with the body of someone else, rather than your original body—a little booth I could walk in, dissolve in a tingly glowy special effect for a few seconds, and walk out looking like (say) [Nana Visitor (circa 1998)](https://memory-alpha.fandom.com/wiki/Kay_Eaton?file=Kay_Eaton.jpg). (In the folklore of [female-transformation erotica](/2016/Oct/exactly-what-it-says-on-the-tin/), this machine is often called the ["morphic adaptation unit"](https://www.cyoc.net/interactives/chapter_115321.html).)
+
+This high-level description of a hypothetical fantasy technology leaves some details unspecified—not just the _how_, but the _what_. What would the indistinguishable-from-magical transformation booth do to my brain? [As a preference-revealing thought experiment](https://www.lesswrong.com/posts/DdEKcS6JcW7ordZqQ/not-taking-over-the-world), what would I _want_ it to do, if I can't change [the basic nature of reality](https://www.lesswrong.com/posts/tPqQdLCuxanjhoaNs/reductionism), but if engineering practicalities weren't a constraint? (That is, I'm allowed to posit any atom-configuration without having to worry about how you would get all the atoms in the right place, but I'm not allowed to posit tethering my immortal soul to a new body, because [souls](https://www.lesswrong.com/posts/u6JzcFtPGiznFgDxP/excluding-the-supernatural) [aren't](https://www.lesswrong.com/posts/7Au7kvRAPREm3ADcK/psychic-powers) [real](https://www.lesswrong.com/posts/fdEWWr8St59bXLbQr/zombies-zombies).)
+
+The anti-plug-and-play argument makes me confident that it would have to change _something_ about my mind in order to integrate it with a new female body—if nothing else, my unmodified brain doesn't physically _fit_ inside Nana Visitor's skull. ([One meta-analysis puts the sex difference in intracranial volume and brain volume at](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3969295/) a gaping [Cohen's _d_](/2019/Sep/does-general-intelligence-deflate-standardized-effect-sizes-of-cognitive-sex-differences/) ≈ 3.0 and 2.1, respectively, and Visitor doesn't look like she has an unusually large head.)
+
+Fine—we're assuming that difficulty away and stipulating that the magical transformation booth can make the _minimal_ changes necessary to put my brain in a female body, and have it fit, and have all the motor-connection/body-mapping stuff line up so that I can move and talk normally in a body that feels like mine.
+
+I want this more than I can say. But is that _all_ I want? What about all the _other_ sex differences in the brain? Male brains are more lateralized—doing [relatively more communication within hemispheres rather than between](https://www.pnas.org/content/111/2/823); there are language tasks that women and men perform equally well on, but [men's brains use only the _left_ inferior frontal gyrus, whereas women's use both](/papers/shaywitz-et_al-sex_differences_in_the_functional_organization_of_the_brain_for_language.pdf). Women have a relatively thicker corpus callosum; men have a relatively larger amygdala. Fetal testosterone levels [increase the amount of gray matter in posterior lateral orbitofrontal cortex, but decrease the gray matter in Wernicke's area](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3306238/) ...
+
+Do I want the magical transformation technology to fix all that, too?
+
+Do I have _any idea_ what it would even _mean_ to fix all that, without spending multiple lifetimes studying neuroscience?
+
+I think I have just enough language to _start_ to talk about what it would mean. Since sex isn't an atomic attribute, but rather a high-level statistical regularity such that almost everyone can be cleanly classified as "female" or "male" _in terms of_ lower-level traits (genitals, hormone levels, _&c._), then, abstractly, we're trying to take points from male distribution and map them onto the female distribution in a way that preserves as much structure (personal identity) as possible. My female analogue doesn't have a penis (because then she wouldn't be female), but she is going to speak American English like me and be [85% Ashkenazi like me](/images/ancestry_report.png), because language and autosomal genes don't have anything to do with sex.
+
+The hard part has to do with traits that are meaningfully sexually dimorphic, but not as a discrete dichotomy—where the sex-specific universal designs differ in ways that are _subtler_ than the presence or absence of entire reproductive organs. We are _not_ satisfied if the magical transformation technology swaps out my penis and testicles for a functioning female reproductive system without changing the rest of my body, because we want the end result to be indistinguishable from having been drawn from the female distribution (at least, indistinguishable _modulo_ having my memories of life as a male before the magical transformation), and a man-who-somehow-has-a-vagina doesn't qualify.
+
+The "obvious" way to to do the mapping is to keep the same percentile rank within each trait, but take it with respect to the target sex's distribution. I'm 5′11″ tall, which [puts me at](https://dqydj.com/height-percentile-calculator-for-men-and-women/) the 73rd percentile for American men, about 6/10ths of a standard deviation above the mean. So _presumably_ we want to say that my female analogue is at the 73rd percentile for American women, about 5′5½″.
+
+You might think this is "unfair": some women—about 7 per 1000—are 5′11″, and we don't want to say they're somehow _less female_ on that account, so why can't I keep my height? But if we refuse to adjust for every trait for which the female and male distributions overlap (on the grounds that _some_ women have the same trait value as my male self), we don't end up with a result from the female distribution.
+
+The typical point in a high-dimensional distribution is _not_ typical along each dimension individually. [In 100 flips of a biased coin](http://zackmdavis.net/blog/2019/05/the-typical-set/) that lands Heads 0.6 of the time, the _single_ most likely sequence is 100 Heads, but they're only one of those and you're _vanishingly_ unlikely to actually see it. The sequences you'll actually observe will have close to 60 Heads. Each such sequence is individually less probable than all Heads, but there are vastly more of them.
+
+Statistical sex differences are like flipping two different collections of coins with different biases, where the coins represent various traits. Learning the outcome of any individual flip, doesn't tell you which which set the coin came from, but if we look at the aggregation of many flips, we can get _godlike_ confidence as to which collection we're looking at.
+
+A single-variable measurement like height is like a single coin: unless the coin is _very_ biased, one flip doesn't tell you much. But there are lots of things about people for which it's not that they can't be measured, but that the measurements require _more than one number_.
+
+Take faces. People are [verifiably very good at recognizing sex from (hair covered, males clean-shaven) photographs of people's faces](/papers/bruce_et_al-sex_discrimination_how_do_we_tell.pdf) (96% accuracy, which is the equivalent of _d_ ≈ 3.5), but we don't have direct introspective access into what _specific_ features our brains are using to do it; we just look, and _somehow_ know. The differences are real, but it's not a matter of any single measurement: [covering up the nose makes people slower and slightly worse at sexing faces, but people don't do better than chance at guessing sex from photos of noses alone](/papers/roberts-bruce-feature_saliency_in_judging_the_sex_and_familiarity_of_faces.pdf).
+
+Notably, for _images_ of faces, we actually _do_ have magical transformation technology. AI techniques like [generative adversarial networks](https://arxiv.org/abs/1907.10786) and [autoencoders](https://towardsdatascience.com/generating-images-with-autoencoders-77fd3a8dd368) can learn the structure of the distribution of face photographs, and use that knowledge to [synthesize faces from scratch](https://thispersondoesnotexist.com/) and
+
+[...]
+
+The same moral applies to sex differences in psychology. I'm a pretty weird guy, in more ways than one. I am not prototypically masculine. Most men are not like me. If I'm allowed to cherry-pick what measurements to take, I can name ways in which I'm more female-typical than male-typical. (For example, I'm _sure_ I'm above the female mean in [Big Five Neuroticism](https://en.wikipedia.org/wiki/Big_Five_personality_traits).) But "weird" represents a much larger space of possibilities than "normal", much as [_nonapples_ are a less cohesive category than _apples_](https://www.lesswrong.com/posts/2mLZiWxWKZyaRgcn7/selling-nonapples).
+
+If you _sum over_ all of my traits, everything that makes me, _me_—it's going to be a point in the _male_ region of the existing, unremediated, genderspace. In principle, you could define a procedure that maps that point to the female region of configuration space in some appropriately structure-preserving way, to compute my female analogue who is as authentically _me_ as possible while also being authentically female, down to the proportion of gray matter in her posterior lateral orbitofrontal cortex and—the love of a woman for a man.
+
+[...]
+
+Okay. Having supplied just enough language to _start_ to talk about what it would mean to actually become female—is that what I _want_? I mean, I would definitely be extremely eager to _try_ it ...
+
+I had said we're assuming away engineering difficulties in order to make the thought experiment more informative about pure preferences, but let's add back one constraint to _force_ the thought experiment to be informative about preferences, and not allow the wishy-washy evasion of "I'm eager to _try_ it."
+
+What if I can't just "try" it? What if the machine can only be used once? Come up with whatever frame story you want for this: maybe the machine costs my life savings just to rent for two minutes, or maybe the transformation process is ever-so-slightly imperfect, such that you can't re-transform someone who's already been transformed once, like a photocopy being a perfectly acceptable substitute for an original document, but photocopies-of-photocopies rapidly losing quality.
+
+In that case, if I have to choose—I _don't_ think I want to be Actually Female. I _like_ who I am on the inside, and don't need to change it. So, I guess ... if I'm being honest ... I guess I _want_ to be a normal man wearing a female body like a suit of clothing.
+
+Is that weird? Is that wrong?
+
+Okay, yes, it's _obviously_ weird and wrong, but should I care more about not being weird and wrong, than I do about my deepest most heartfelt desire that I've thought about every day for the last eighteen years?
+
+This is probably counterintuitive if you haven't been living with it your entire adult life? People have _heard of_ the "born in the wrong body" narrative, which makes intuitive sense: if female souls are designed to work female bodies, and you have a female soul tethered to a male body, you can imagine the soul finding the mismatch distressing and wanting to fix it. But if, as I'm positing for my case, there _is no mismatch_ in any objective sense, then where does the desire come from? How do you make sense of wanting to change physiological sex, for reasons that _don't_ have anything to do with already neurologically resembling that sex? What's really going on there, psychologically?
+
+Part of what makes this so hard to talk about _besides_ it being weird and wrong, is that we don't really understand how our own minds work in a legible way; we just experience things. Even if you're [not sure that other people really see "the same" colors as you](https://www.lesswrong.com/posts/3wYjyQ839MDsZ6E3L/seeing-red-dissolving-mary-s-room-and-qualia) (and you don't know how to [reformulate the question](https://www.lesswrong.com/posts/rQEwySCcLtdKHkrHp/righting-a-wrong-question) [to not](https://www.lesswrong.com/posts/Mc6QcrsbH5NRXbCRX/dissolving-the-question) [be confused](https://www.lesswrong.com/posts/XzrqkhfwtiSDgKoAF/wrong-questions)), you can at least agree on color _words_ by pointing to [Pantone swatches](https://en.wikipedia.org/wiki/Pantone#Pantone_Color_Matching_System), but I'm not sure I have the language to convey the facts about the qualia I associate with the word _autogynephilia_ to someone who doesn't already feel something similar.
+
+But I have to try. A clue: when I'm ... uh. When I'm—well, you know ...
+
+(I guess I can't evade responsibility for the fact that I am, in fact, blogging about this. This is the eye of the hurricane; this is the only way I can [protect](http://unremediatedgender.space/2019/Jul/the-source-of-our-power/)—)
+
+A clue: when I'm masturbating, and imagining all the forms I would take if the magical transformation technology were real (the frame story can vary, but the basic idea is always the same), I don't think I'm very _good_ at first-person visualization? The _content_ of the fantasy is about _me_ being a woman (I mean, having a woman's body), but the associated mental imagery mostly isn't the first-person perspective I would actually experience if the fantasy were real; I'm mostly imagining a specific woman (which one, varies a lot) from the outside, admiring her face, and her voice, and her breasts, but wanting the soul behind those eyes to be _me_. Wanting _my_ body to be shaped like _that_, to be in control of that avatar of beauty, and just to live like that.
+
+If the magical transformation technology were real, I would want a mirror. (And in the real world, I would probably crossdress a _lot_ more often, if I could pass to myself in the mirror.)
+
+What's going on here? The sexologist James Cantor [speculates](https://youtu.be/q3Ub65CwiRI?t=281): mirror neurons.
+