The human tendency to fly off the handle

Slate - Why are humans so quick to take offense

A long article with many references, most of which is a romp through a bunch of sociology, psychology and evolutionary psychology thinkers. Taking offense at small slights is an age-old human behavior. First, rationality is often co-opted by one's sense of fairness, and even one's sense of vengance: in an 'ultimatum game', actors will only settle for a roughly even split-- any less and the actor will punish both sides (spite rather than self-interest). Different scientists postulate the evolved ability to calculate fairness and punish cheaters which has, paradoxically, given us both the ability to build relationships and cooperate, but also to treat small infractions harshly. Some posit the need to keep up with all the different social moties, moves, and relationships was a sufficient cause for developing language. Those who speak out and take a hard line against open infractions actually reduce the level of aggression in groups, some studies show.