-[distinguish between "identity" as the Schelling _dimension_ (age rather than maturity), and also the slippery slope on rights (if pronoun, why not bathroom; if bathroom, by not sports?)]
+If, despite this, [social reality](/2019/Aug/the-social-construction-of-reality-and-the-sheer-goddamned-pointlessness-of-reason/) continues to require the question to have a definite canonical answer, the natural Schelling point is, "Just _ask_ the person what gender they are, and that's what they are." _Even if_ we [_don't_ assume that people know themselves better than anyone else](http://unremediatedgender.space/2016/Sep/psychology-is-about-invalidating-peoples-identities/), people are still the focal point for reasonable mutual expectations about knowledge about themselves: if I claim to know Pat's gender better than she knows herself, and you claim to know Pat's gender better than _he_ knows _himself_, then there's no obvious way to break the symmetry except to defer the question to Pat.
+
+(Notably, this is also the procedure you would use for non-trans people who just happen to be really-really androgynous: you're going to believe their answer to "Are you a woman or a man?" because if you could tell, then you wouldn't have asked.)
+
+Schelling points are "sticky." If the set of possible choices is ordered, and it's possible to "move" from a currently-selected choice towards a "nearby" one, then the selected option may [slide down a "slippery slope" until stopping at a Schelling point](https://www.lesswrong.com/posts/Kbm6QnJv9dgWsPHQP/schelling-fences-on-slippery-slopes). Imagine the armies of two countries fighting over contested territory containing a river. The river is a Schelling point for the border between the two countries—unless one of the armies has a military advantage to push the battle line forward to the _next_ Schelling point, we expect peace-treaty negotiations to settle on the river as the border. There's no particular reason that the border couldn't be drawn 2 kilometers north of the river, _except_ that that would invite the question of, "Why 2 kilometers? Why not 1, or 3?"
+
+The coordination problem of _who_ has the authority to decide what "gender" a person is, can be seen of a particular case of the problem of how to decide what gender a person is _in a particular context_. The notion of the same person's "gender" being differnt in different contexts may seem strange, but again, in the absence of magical perfect sex-change technology, we _kind of_ need it: as far as the practice of medicine is concerned, there's no getting around the fact that pregnant trans men are female. (Even if the doctors _address_ the patient as "Mr.", "he", _&c._ they still need to draw on their knowledge of the _female_ reproductive system to practice their craft, and they might need _language_ that reflects what they're actually thinking.)
+
+[...]