Moral credential effect (moral licensing)

Biological Parallel

Vampire bats that share food with hungry roost-mates sometimes defect afterward, apparently "licensing" selfish behavior after prosocial acts—creating a balance sheet where prior generosity offsets future selfishness. Similarly, cleaner wrasse that remove parasites honestly from several clients will occasionally cheat (eat mucus) on the next, as if good behavior builds "credit." Moral licensing—using virtuous acts to justify subsequent indulgence—may reflect reciprocal altruism accounting: reputation systems track lifetime balance, not individual transactions, so occasional defection after cooperation could exploit the system's averaging without triggering punishment.