Behavioural Law and Economics as Litmus Test

This paper discusses a few meta-theoretical questions about Behavioural Law and Economics (BLE) in order to better understand both its popularity and the criticisms it has received. It argues that BLE provides a litmus test to reveal dividing lines, manifest latent tensions and polarize debates between various camps or traditions in both positive and normative (law and) economics, thus making epistemic and methodological commitments of economists more visible. These dividing lines include the methodological character of rationality assumptions, naturalistic and mentalist models of human behaviour, and the normative force and relevance of individual preferences, autonomy and objective metrics of welfare.