Why Normative Behaviourism Does Not Improve Political Realism

Abstract Focusing on ‘real actions’ of ‘real people’, normative behaviourism turns facts about observable patterns of behaviour into grounds for specific normative political principles. For this reason, this way of doing normative political theory has strong political realist credentials, given its methods, values and ambitions. In fact, according to its supporters, normative behaviourism is an improvement of political realism since it solves two problems that allegedly face many realists, namely, the ‘legitimacy problem’, i.e., how we should distinguish genuine acceptance of a political system from false acceptance, and ‘the institutional problem’, i.e., how we should translate political principles into viable political institutions. In this paper, we make two claims. First, normative behaviourism does not solve the legitimacy problem encountered by realists, because its solution rests on a flawed distinction between foundational principles and ‘principles that matter’, together with a problematic use of a Humean internal reasons approach. Second, normative behaviourism does not solve the institutional problem encountered by realists, because its solution is in fact much more unfeasible than realist prescriptions, since feasibility is interpreted as mere possibility. We wind up our analysis by showing that normative behaviourism encounters new problems that realist approaches typically do not face.