People infer local rules from scarce evidence, internalise them, monitor others for compliance and punish violations, which is what makes arbitrary norms stable.
The proposal is that humans possess a dedicated readiness for norms rather than general learning applied to them: children over-imitate irrelevant steps, treat observed regularities as obligatory, and object when others deviate, well before they can say why. Stability then needs no enforcement authority, because the monitoring is distributed and largely unconscious.
In practice
- A new joiner copies a pointless step in the process and objects within a month when someone skips it.
- An office whose dress code was never written is enforced by nobody in particular and holds for a decade.