Tags: game theory, sociology
Status: draft
-Previously on _The Scintillating But Ultimately Untrue Thought_, we've considered at length the ways in which the self-identity criterion for gender ("Women are people who identify as women") fails to
+Previously on _The Scintillating But Ultimately Untrue Thought_ (["The Categories Were Made for Man to Make Predictions"](/2018/Feb/the-categories-were-made-for-man-to-make-predictions/), ["Reply on Adult Human Females"](/2018/Apr/reply-to-the-unit-of-caring-on-adult-human-females/)), we've considered at length the ways in which the self-identity criterion for gender (_e.g._, "Women are people who identify as women") fails to satisfy some of the basic desiderata for useful categories: the _cognitive function_ of categories is to group similar things together so that our brains can make similar predictions about them under conditions of uncertainty. In order to _make the case_ that it's useful to think and speak such that "identifying as" a gender is the same as _being_ of that gender, one would need to show that those who identify as a gender form a natural [cluster in configuration space](https://www.lesswrong.com/posts/WBw8dDkAWohFjWQSk/the-cluster-structure-of-thingspace) (and [not just a uselessly low-dimensional subspace thereof](https://www.lesswrong.com/posts/esRZaPXSHgWzyB2NL/where-to-draw-the-boundaries)).
+Interestingly, a extension of this line of reasoning suggests an apparently novel argument in _favor_ of the self-identity criterion! Let me explain.
+(And please don't tell me you're surprised that I'm [inventing novel arguments for the position I've spent the last twenty months of my life obsessively arguing against!](https://archive.is/jPmyd) Policy debates [should not appear one-sided](https://www.lesswrong.com/posts/PeSzc9JTBxhaYRp9b/policy-debates-should-not-appear-one-sided): it is _by means of_ searching for and weighing all relevant arguments, that one _computes_ the optimal policy, and [even generally terrible positions will have _some_ arguments supporting them](https://www.lesswrong.com/posts/627DZcvme7nLDrbZu/update-yourself-incrementally). What did you take me for, some kind of _partisan hack?!_)
+[As my favorite author on _Less Wrong_ explains](https://www.lesswrong.com/posts/edEXi4SpkXfvaX42j/schelling-categories-and-simple-membership-tests), another desideratum for _intersubjectively_ useful categories is being easy for different people to _coordinate_ on: in order to work together and _think_ together, we don't just want to choose predictively-useful category boundaries, we also want to make the _same_ choices.
+The author gives the age of majority as an example. Presumably the right to vote should be based on _relevant_ features of a person (in a word, "maturity"), not how many times the Earth has gone around the sun since they were born. But it wouldn't be practical for everyone to come to consensus on how to assess "maturity", whereas it _is_ practical for everyone to come to consensus on how to subtract dates, so our _shared_ socially-constructed category of "legal adulthood" ends up being defined in terms of a semi-arbitrary age cut-off, at the cost of mature 16-year-olds and immature 20-year-olds losing out on or gaining privileges that they should or shouldn't have (respectively).
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+When people need to coordinate on making the _same_ arbitrary choice, they tend to converge on whatever option is (for whatever reason) most salient. This is the concept of a "Schelling point", after famed economist Thomas Schelling, who posed the question of where strangers should attempt to meet in New York, if they couldn't communicate to pick a rendezvous point in advance. The plurality answer turns out to be "noon at the information booth at Grand Central Station", not because of any properties that make it an objectively superior meeting place that you would pick even if you _could_ communicate in advance, but just because its centrality makes it the focus of reasonable mutual expectations about what your partner is likely to do.
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+Schelling points are "sticky."
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+https://www.lesswrong.com/posts/Kbm6QnJv9dgWsPHQP/schelling-fences-on-slippery-slopes
-https://www.lesswrong.com/posts/edEXi4SpkXfvaX42j/schelling-categories-and-simple-membership-tests