Punishing Heretics

Heathens vs Heretics

These are my notes on Scott Alexander’s post: In Favor of Niceness, Community, And Civilization.

Why do religions persecute heretics more than heathens? In Scott’s example, why do Catholics oppose Protestants so much, when Hindus disbelieve Catholicism more than anybody else?

We punish heretics so much because we are otherwise inclined to cooperate with them on the Prisoner’s Dilemma. We feel like letting them hang out with us, but then they betray our trust by stealing our stuff (or converting our gullible friends). So, we must make it doubly clear to our people that these heretics are not to be cooperated with.

On the other hand, we are much less severe regarding heathens because we are not so inclined to cooperate with them (at least in the religious domain). We know that their our differences are apparent and that neither we nor the most gullible of our friends will fall for their tricks, so we don’t need to make any extra effort to label them. We know that any person who converts to the foreign religion will seem very different and thus lose all the benefits they had enjoyed as part of our community, which were probably substantial once the community was large and powerful enough.

Meanwhile, the heathens aren’t enthusiastic about cooperating with us for the same reasons. Their ties with their own community are too valuable to throw away in trying to mix with us in any way in the religious domain (maybe by doing rituals from both the religions).

Thus, we have a solid game-theoretic reason for the seemingly “irrational” behaviour of religions that punish slightly-different heretics. The same holds for all the ideologies that do this. It goes, I think, even for cliques in school or college where people hurt you far worse for being slightly different than for being completely different. They’re just sending a message to all the other members of their clan: this guy is not to be trusted.

Notes

What is the exact game here? What do “cooperation” and “defection” entail? Note that both players must face the same choice and they must choose simultaneously.