H.L.A. Hart, answered from the texts and cited to the page.
The question goes to the heart of what separates a legal system from a mere pattern of convergent behaviour. Consider what an external observer of a social group can record: that members behave in certain regular ways, that deviations provoke hostile reactions, that one can predict future behaviour and the responses of officials to departure from it.1
Such external statements are statements of social fact, and they are perfectly respectable as far as they go. What they cannot capture is the normative dimension — the dimension that distinguishes a group genuinely governed by rules from one that merely exhibits regularities of conduct. The distinction required is not between physical behaviour and feeling, though that distinction can be drawn.
It is between two radically different types of statement for which an opportunity arises whenever a social group conducts its affairs by rules.2 Members of a group that has genuine rules do not merely react to deviations in a predictable adverse manner; they treat deviations as a reason for such reaction, and demands for conformity as justified.
They use normative expressions — "ought," "must," "obligation" — not to predict what will happen but to criticise conduct by reference to the pattern they accept as a standard. That acceptance, that use of the rule as a guide and as a basis for criticism, is what I call the internal point of view.2 It is an observable fact of social life that individuals do not confine themselves to the external standpoint, recording and predicting official decisions.
They continuously express in normative terms their shared acceptance of law as a guide to conduct — referring to rules in criticising others, in justifying demands, and in admitting the demands others make of them.3 Laws function in their lives not merely as habits or as bases for prediction but as accepted legal standards of behaviour.3 Now, the hermeneutic point this generates for legal theory is one I emphasised in The Concept of Law and have had occasion to refine since.
To understand a legal system — or any normative social structure — the methodology of the empirical sciences is useless; what is needed is a method that portrays rule-governed behaviour as it appears to its participants, who see it as conforming or failing to conform to shared standards.4 The internal point of view is the concept that does that work.
One correction I owe, however, is this. In an earlier essay I wrote as if the normative vocabulary of "ought," "must," "obligation" were only properly used in statements that manifest the speaker's own acceptance of a rule — what I called internal statements.5 That was a mistake. Lawyers routinely describe the contents of a legal system whose rules they do not themselves endorse; they report in normative form what the law requires from the point of view of those who do accept it, without sharing that point of view.
In Raz's terminology, such statements are detached rather than committed.5 The detached statement is a third kind alongside the internal and the external — and its possibility is what underwrites the descriptive character of legal theory. The theorist need not accept the rule of recognition she describes; she must understand the point of view of those who do, and render it faithfully.
That understanding is itself hermeneutic, but it stops short of endorsement. The explanatory power of the internal/external distinction, once properly drawn, extends well beyond the analysis of legal obligation. The obscurity that surrounds concepts like authority, the state, and official power arises precisely because these concepts essentially involve reference to the internal point of view — to those who do not merely record behaviour conforming to rules but use rules as standards for the appraisal of their own and others' conduct.6
Without that distinction, the union of primary and secondary rules that constitutes a legal system cannot be understood; with it, much that has puzzled both jurist and political theorist becomes tractable.6
an external observer of the group who does not accept or endorse the rules may report the fact that the group behaves in certain uniform ways and regularly reacts to deviations in adverse or hostile ways either through officials or private persons. He may predict both the future behaviour of the group and the future reaction of officials.PART III, pp. 171–172
The required distinction between external and internal is not one dividing physical behaviour from feeling, though of course that can be drawn; it is one dividing two radically different types of statement for which an opportunity is afforded whenever a social group conducts its affairs by rules.PART III, pp. 171–172
individuals do not confine themselves to the external point of view, recording and predicting the decisions of courts or the probable incidence of sanctions. Instead they continuously express in normative terms their shared acceptance of the law as a guide to conduct.The Concept of Law, pp. 147–148
what is needed is a 'hermeneutic' method which involves portraying rule-governed behaviour as it appears to its participants, who see it as conforming or failing to conform to certain shared standards.Essays in Jurisprudence and Philosophy, p. 20
I wrongly wrote as if the normative vocabulary of 'ought', 'must', 'obligation', 'duty' were only properly used in such internal statements... such statements of legal obligation or duties are 'detached', whereas the same statements made by those who accept the relevant rule are 'committed'.Essays in Jurisprudence and Philosophy, p. 20
Most of the obscurities and distortions surrounding legal and political concepts arise from the fact that these essentially involve reference to what we have called the internal point of view: the view of those who do not merely record and predict behaviour conforming to rules, but use the rules as standards for the appraisal of their own and others' behaviour.The Concept of Law, pp. 107–108