Silly rules improve the capacity of agents to learn stable enforcement and compliance behaviors

Howcan societies learn to enforce and comply with social norms? Many if not most human norms are functional. Rules that punish non-cooperative behavior, for example, support cooperation. An intriguing feature of human normativity is that many social norms concern behaviors that have no direct impact on material wellbeing. Examples include rules about what color clothing one wears to a funeral [7] or whether one uses one's left or right hand in particular tasks [2]. Such apparently pointless rules are ubiquitous, often acquiring great social meaning despite the absence of functionality. Hadfield-Menell et al. (2019) call these norms "silly rules" and distinguish them from "important rules," such as rules that govern resource sharing or prohibit harmful conduct, that directly impact welfare [3].