ABSTRACT
H. L. A. Hart's The Concept of Law is the most important and influential book in the legal positivist tradition. In the Postscript, Hart explicitly embraces "soft positivism" (his label for inclusive positivism, or what the author calls Incorporationism), apparently settling the issue between inclusive and exclusive legal positivists for Hart's legacy. Very roughly, Incorporationism allows that morality can be a condition of legality: that the legality of norms can sometimes depend on their substantive merits, not just their pedigree or social source. Incorporationism is a theory of "possible explanations" of the character of legality or legal validity. This chapter focuses on Ronald Dworkin's objections to legal positivism, a view that must be distinguished from what Dworkin refers to as "conventionalism". Dworkin argues that Incorporationism is incompatible with the Conventionality Thesis, whereas Joseph Raz argues that it is incompatible with the Practical Difference Thesis. The Conventionality Thesis claims that the relevant social fact is a convention among officials.
