Hart uses this distinction inconsistently to mark a difference of (a) normative type (81: primary rules as duty-imposing, secondary rules as power-conferring); (b) object (94, 97: primary rules govern conduct, secondary rules govern rules); (c) social function (40–1: primary rules direct behaviour, secondary rules provide facilities); (d) importance (91, 235: primary rules are essential to human society, secondary rules are valuable but optional); and (e) genesis (91, 95: primary rules emerge first, secondary rules later).

H. L. A Hart, The Concept of Law, loc. 789