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Unpublished Paper
Incommensurability, Practices and Points of View: Revitalizing H.LA. Hart’s Practice Theory of Rules
ExpressO (2011)
  • Eric J. Miller

The standard reading of H.L.A. Hart’s practice theory of rules is that it failed to provide a sufficient normative basis for a theory of law. That standard reading rests upon a significant misunderstanding: that Hart has an exclusionary reason approach to law. Instead, Hart understands law to be a social practice, one capable of generating valid norms that not only block the operation of moral norms, but which are wholesale incommensurable with them.

Wholesale incommensurability entails that law, as a form of social practice, constitutes a discrete normative system in which the truth-conditions of legal propositions are distinct from the truth-conditions of moral propositions: put differently, normative terms such as right, duty, obligation, permission, and so on, have a different meaning in law as in morality, because made true by different facts.

The upshot is that Hart takes a distinctively strong view of judicial power: judges can expressly reject morality in the course of their decision-making. The power possessed judicial authority rests on no more, but no less, than a set of social conventions, and judges get the power to decide cases based on those conventions alone. The practice of law enables the judge to change and determine the scope of these conventions, as well as to impose them on others. And the judge may use the practice of law to pursue her own agendas: her underlying moral, political, or personal motivations are irrelevant to the validity of law or of her individual decisions from the legal point of view.

  • Hart,
  • practice theory,
  • incommensurability,
  • exclusionary reasons,
  • Raz,
  • philosophy,
  • legal point of view
Publication Date
October 4, 2011
Citation Information
Eric J. Miller. "Incommensurability, Practices and Points of View: Revitalizing H.LA. Hart’s Practice Theory of Rules" ExpressO (2011)
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