Eight pages, but worth it, I thought. Thanks!
Just before the conclusion Pinker states a principle I’ve found to be a pretty hard sell in BB political threads:
As soon as your fate depends on the behavior of other people and you engage them in any kind of dialogue, you can’t maintain that your interests are privileged simply because you’re the one who has them and expect them to take you seriously, any more than you can say that the point that you happen to be standing on is a privileged spot in the universe because you happened to be standing on it at that very moment.
It’s this core idea of the interchangeability of perspectives, or the recognition of other people’s interests, that’s the true basis of morality, as we see in numerous moral precepts and moral codes - the Golden Rule, Singer’s expanding circle, Kant’s categorical imperative, and Rawls’ veil of ignorance.
Also thank you @GulliverFoyle and @popobawa4u for having your interesting and thought-provoking interchange here in public where I can read it. 
I wonder if anyone has ever studied how people with larger ideas of community protect those who do not share them, or tried to measure how deeply people who act to shrink or restrict communities (by othering and purity tests, for example) sabotage those same communities.
