I’ve been reflecting on how useless government sanctions have turned out to be in influencing behavior. I think it’s because they’re effectively forever; until the sanctioned meet some criteria of change, we will just keep the sanctions on.

Some years ago, it was shown that Tit-For-Tat was a winning strategy to harness cooperation from unknown parties. Trust by default, a short but sharp punishment for betrayal, and a reversion to trust. I think this probably works with people, too, because we are more sensitive to change than to steady state, so the punishment is most effective immediately, and wears into a sullen resentment over time. You don’t punish a kid’s staying out too late by banning them from going out until they’ve proved they’re worthy of a reprieve, you punish them with a short but severe cost and then go back to the trust position. So this is a way to regain trust.

It’s clear that cooperation is evolutionarily adaptive on the group level, too. Trust-by-default leads to better outcomes. So tit-for-tat would seem to be the right way to deal with betrayal, because it encourages trust-by-default. How do we deal rationally with repeated betrayal?