Yes, I remember the 80s, and the USSR was one of those things you just assumed would be around for the foreseeable future, like marijuana prohibition (though fo

Yes, I remember the 80s, and the USSR was one of those things you just assumed would be around for the foreseeable future, like marijuana prohibition (though for that one there was more of an inkling of possibility given more time). What you can say "within reason" depends on what you think everyone else thinks you can say, so equilibria are both really stable and subject to surprising flips when they finally tip over -- sort of like digital logic.