Hart distinguishes between social habits and social rules. While following social habits is habitual, breaking them does not bring about harsh criticism or censure. Breaking social rules on the other hand does. Social rules seem to bind us and laws seem to be social rules. There are two perspectives to this: the external aspect and the internal aspect. The external aspect is the independently observable fact that people do tend to regularly follow the rules. The internal aspect is one’s sense of obligation to follow the rule. It is from this aspect which the law acquires its normative quality. This aspect is also know as the “critical reflective attitude.” Hart calls the populace’s obedience of a rule “efficacy.” For a law to be efficacious, the majority of the populace must follow it. While the average citizen of a modern state with a developed legal system may feel compelled by the internal aspect, it is more important for the officials of the society to feel compelled by it since they must follow constitutional provisions they could ignore with impunity.
Laws are more than just rules of conduct. There are two types of laws: primary rules and secondary rules. Primary rules are rules of conduct. Secondary rules are rules that apply to officials and govern the execution of primary rules. Secondary rules address three problems: The first is the problem of the uncertainty regarding what the law is. A secondary rule Hart calls “the rule of recognition” states the criteria for the validity of laws. The second is the problem of the rigidity of rules. This problem necessitates “rules of change” which govern changes in the law. The third is the problem of how to resolve legal disputes. This problem gives rise to “rules of adjudication.”
According to Hart, a legal system consists of the union of primary and secondary rules. Finally, Hart disagrees with Austin’s command theory. Hart argues that laws are broader in scope than coercive orders. Laws enable those under their authority to carry out authoritative acts themselves, such as the making of legally enforceable wills and contracts.