+Daphna Joel _et al._ [argue](https://www.pnas.org/content/112/50/15468) [that](https://www.pnas.org/content/112/50/15468) human brains are "unique 'mosaics' of features" that cannot be categorized into distinct _female_ and _male_ classes, because it's rare for brains to be "internally consistent"—female-typical or male-typical along _every_ dimension. It's true and important that brains aren't _discretely_ sexually dimorphic the way genitals are, but as [Marco del Giudice _et al._ point out](http://cogprints.org/10046/1/Delgiudice_etal_critique_joel_2015.pdf), the "cannot be categorized into two distinct classes" claim seems false in an important sense. The lack of "internal consistency" in Joel _et al._'s sense is exactly the behavior we expect from multivariate normal-ish distributions with different-but-not-vastly-different means. (There aren't going to be many traits where the sexes are like, _four_ or whatever standard deviations apart.) It's just like how sequences of flips of a Heads-biased and Tails-biased coin are going to be unique "mosaics" of Heads and Tails, but pretty distinguishable with enough flips—and indeed, with the right stats methodology, [MRI brain scans can predict sex at 96.8% accuracy](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6374327/).
+
+Sex differences in the brain are like sex differences in the skeleton: anthropologists can tell female and male skeletons apart (the [pelvis is shaped differently](https://johnhawks.net/explainer/laboratory/sexual-dimorphism-pelvis), for obvious reasons), and [machine-learning models can see very reliable differences that human radiologists can't](/papers/yune_et_al-beyond_human_perception_sexual_dimorphism_in_hand_and_wrist_radiographs.pdf), but neither sex has entire _bones_ that the other doesn't, and the same is true of brain regions. (The evopsych story about complex adaptations being universal-up-to-sex suggests that sex-specific bones or brain regions should be _possible_, but in a bit of _relative_ good news for antisexism, apprently evolution didn't need to go that far. Um, in humans—a lot of other mammals actually have [a penis bone](https://en.wikipedia.org/wiki/Baculum).)
+
+Maybe this should just look like supplementary Statistics Details brushed over some basic facts of human existence that everyone knows? 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 my mosaic is 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).) ["[A] weakly negative correlation can be mistaken for a strong positive one with a bit of selective memory."](https://www.lesswrong.com/posts/veN86cBhoe7mBxXLk/categorizing-has-consequences)
+
+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): a woman trapped in a man's body would be weird, but it doesn't follow that weird men are secretly women, as opposed to some other, _specific_, kind of weird. 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 the course of _being myself_, I'm going to do more male-typical things than female-typical things, not becuase I'm _trying_ to be masculine (I'm not), and not because I "identify as" male (I don't—or I wouldn't, if someone could give me a straight answer as to what this "identifying as" operation is supposed to consist of), but because I literally in-fact am male in the same sense that male chimpanzees or male mice are male, whether or not I like it (I don't—or I wouldn't, if I still believed that preference was coherent), and whether or not I _notice_ all the little details that implies (I almost certainly don't).
+
+Okay, maybe I'm _not_ completely over my teenage religion of psychological sex differences denialism?—that belief still feels uncomfortable to put my weight on. I would _prefer_ to believe that there are women who are relevantly "like me" with respect to some fair (not gerrymandered) metric on personspace. But, um ... it's not completely obvious whether I actually know any? (Well, maybe two or three.) When I look around me—most of the people in my robot cult (and much more so if you look the core of old-timers from the _Overcoming Bias_ days, rather than the greater "community" of today) are male. Most of the people in my open-source programming scene are male. These days, [most of the _women_](/2020/Nov/survey-data-on-cis-and-trans-women-among-haskell-programmers/) in [my open-source programming scene](/2017/Aug/interlude-vii/) are male. Am ... am I not supposed to _notice_?
+
+Is _everyone else_ not supposed to notice? Suppose I got the magical body transformation (with no brain mods beyond the minimum needed for motor control). Suppose I caught the worshipful attention of a young man just like I used to be ("a" young man, as if there wouldn't be _dozens_), who privately told me, "I've never met a woman quite like you." What would I be supposed to tell him? ["There's a _reason_ for that"](https://www.dumbingofage.com/2014/comic/book-5/01-when-somebody-loved-me/purpleandskates/)?
+
+In the comments to [a post about how gender is built on innate sex differences](https://web.archive.org/web/20130216025508/http://lesswrong.com/lw/rp/the_opposite_sex/) (of which I can only link to the Internet Archive copy, the original having been quietly deleted sometime in 2013—I wonder why!), Yudkowsky opined that "until men start thinking of themselves _as men_ they will tend to regard women as defective humans."
+
+From context, it seems like the idea was targeted at men who disdain women as a mysterious Other—but the same moral applies to men who are in ideologically-motivated denial about how male-typical they are, and whether this has implications. [At the time, I certainly didn't want to think of myself _as a man_.](https://www.greaterwrong.com/posts/FBgozHEv7J72NCEPB/my-way#comment-7ZwECTPFTLBpytj7b) And yet ...
+
+For example. When I read things from the [systematizing–empathizing](https://en.wikipedia.org/wiki/Empathising%E2%80%93systemising_theory)/"men are interested in things, women are interested in people" line of research—which, to be clear that you know that I know, is [only a mere statistical difference at a mere Cohen's _d_ ≈ 0.93](http://unremediatedgender.space/papers/su_et_al-men_and_things_women_and_people.pdf), not an absolute like genitals or chromosomes—my instinctive reaction is, "But, but, that's not _fair_. People _are_ systems, because _everything_ is a system. [What kind of a lame power is empathy, anyway?](https://tvtropes.org/pmwiki/pmwiki.php/Main/WhatKindOfLamePowerIsHeartAnyway)"
+
+[But the map is not the territory](https://www.lesswrong.com/posts/np3tP49caG4uFLRbS/the-quotation-is-not-the-referent). We don't have unmediated access to reality beyond [the Veil of Maya](https://web.archive.org/web/20020606121040/http://singinst.org/GISAI/mind/consensus.html); system-ness in the empathising/systemising sense is a feature of our _models_ of the world, not the world itself.
+
+So what "Everything is a system" _means_ is, "I _think_ everything is a system."
+
+I think everything is a system ... because I'm male??