Here are some metrics for strength of a community you're building: first relationship between community members. First marriage. First baby.
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Relevant to my particular circles: the rationalist community seems to be doing better on this than the post-rationalist community
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You should also factor in that the postrat 'community' really really does not want to be one. It's only rationalists who see any commonality
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They don't want to be unified, but they're usually willing to link to each other and chat on Twitter. It's the Hanseatic League not the HRE.
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True, but random forest is simply not even that connected here. The couple you're thinking of does not even know the twitter UST for eg

