The main criticism of positivist theses since they rose to prominence within theory of law has usually been based on their inadequate understanding of the operation of the application of normative judgement. The realist critique essentially stemmed from work in the sociological and realist theory of law and sought to expose the lack of scientific precision in the positivist definition of law. From among the many objections levelled at this hermeneutic critique of legal positivism and more precisely at the version developed by R. Dworkin, we will address here only the one formulated by J. Coleman, which to us appears definitive. The practice of recognition by means of which judges define the criteria for legal normativity within a social group can only be thought as a form of shared cooperative activity (SCA). The way members of a social group determine what is required by courtesy is a function of an interpretive attitude.