Mos Maiorum

Mos maiorum complemented written law as the source of Roman social norms. It governed the household, whose head held great authority yet was expected to use it with moderation, and the bonds of patron and client.

Its virtues included gravitas, shown by Mucius Scaevola, who held his hand in a fire before the Etruscan king Lars Porsenna. Religion belonged to it too: correct rites preserved the peace of the gods.