+_The argument makes sense_. Of course, it's important to notice that you'd need an additional [handwave](https://tvtropes.org/pmwiki/pmwiki.php/Main/HandWave) to explain why the AI in the story doesn't give every _individual_ their separate utopia—if existing women and men aren't optimal partners for each other, so too are individual men not optimal same-sex friends for each other. A faithful antisexist (as I was) might insist that that should be the _only_ moral, as it implies the other [_a fortiori_](https://en.wikipedia.org/wiki/Argumentum_a_fortiori). But if you're trying to _learn about reality_ rather than protect your fixed quasi-religious beliefs, it should be _okay_ for one of the lessons to get a punchy sci-fi short story; it should be _okay_ to think about the hyperplane between two coarse clusters, even while it's simultaneously true that a set of hyperplanes would suffice to [shatter](https://en.wikipedia.org/wiki/Shattered_set) every individual point, without deigning to acknowledge the existence of clusters.
+
+On my reading of the text, it is _significant_ that the AI-synthesized complements for men are given their own name, the _verthandi_ (presumably after [the Norse deity](https://en.wikipedia.org/wiki/Ver%C3%B0andi)), rather than just being referred to as women. The _verthandi_ may _look like_ women, they may be _approximately_ psychologically human, but since the _detailed_ psychology of "superintelligently-engineered optimal romantic partner for a human male" is not going to come out of the distribution of actual human females, judicious exercise of the [tenth virtue of precision](http://yudkowsky.net/rational/virtues/) demands that a _different word_ be coined for this hypothetical science-fictional type of person. Calling the _verthandi_ "women" would be _worse writing_; it would _fail to communicate_ the impact of what has taken place in the story.
+
+Another post in this vein that had a huge impact on me was ["Changing Emotions"](https://www.lesswrong.com/posts/QZs4vkC7cbyjL9XA9/changing-emotions). As an illustration of how [the hope for radical human enhancement is fraught with](https://www.lesswrong.com/posts/EQkELCGiGQwvrrp3L/growing-up-is-hard) technical difficulties, Yudkowsky sketches a picture of just how difficult an actual male-to-female sex change would be.
+
+It would be hard to overstate how much of an impact this post had on me. I've previously linked it on [this](/2016/Nov/reply-to-ozy-on-two-type-mtf-taxonomy/#changing-emotions-link) [blog](/2017/Jan/the-line-in-the-sand-or-my-slippery-slope-anchoring-action-plan/#changing-emotions-link) [five](/2018/Apr/reply-to-the-unit-of-caring-on-adult-human-females/#changing-emotions-link) [different](/2018/Dec/untitled-metablogging-26-december-2018/#changing-emotions-link) [times](/2019/Aug/the-social-construction-of-reality-and-the-sheer-goddamned-pointlessness-of-reason/#changing-emotions-link). In June 2008, half a year before it was published, I encountered the [2004 Extropians mailing list post](http://lists.extropy.org/pipermail/extropy-chat/2004-September/008924.html) that the blog post had clearly been revised from. (The fact that I was trawling through old mailing list archives searching for Yudkowsky content that I hadn't already read, tells you something about what a fanboy I am—if, um, you hadn't already noticed.) I immediately wrote to a friend: "[...] I cannot adequately talk about my feelings. Am I shocked, liberated, relieved, scared, angry, amused?"
+
+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—