Abstract.Legal philosophy must consider the way in which laws function as reasons for action. “Simple positivism” considers laws as merely reasons in the balance of reasons. Joseph Raz, as a representative of “sophisticated positivism,” argues that laws are exclusionary reasons for action, not merely reasons in the balance of reasons. This paper discusses Raz's arguments for his view. The Functional Argument provides no more reason for positivism than against it. The Phenomenological Argument is best supported by an account of how character traits function in explaining behaviour. But then the distinction between exclusionary reasons and expressive reasons is obliterated. Legal positivism cannot absorb laws as expressive reasons for action. Raz's positivism implies the correctness of an anti‐positivistic leg