In this study in recent legal theory, I begin by establishing that the new style of legal positivism, initiated by H. L. A. Hart and developed by Joseph Raz, relies on two assumptions: (1) that an adequate legal theory must not distort the nature of legal systems as seen from the point of view of participants in those systems; (2) that an adequate legal theory must be able to account for legal obligation. I then show that the legal theories of Hart and Raz do not meet these requirements, partly because they deny a conceptual connection between law and morals. Both theories distort the Anglo-American doctrine of precedent, and neither theory can explain legal obligation, even on their own analyses of the concept of obligation. Next, I argue that Ronald Dworkin's legal theory, contrary to recent interpretations of it, does assert a conceptual connection between law and morals, and I sketch this theory in order to show that it does not violate the two requirements mentioned above. I conclude with a brief outline of the constructivist moral theory which underlies Dworkin's legal theory and displays the continuity of his theory of legal obligation with those of Hart and Raz
