What is the point of behavioural public policy? A contractarian approach

Many proponents of behavioural public policy work within a broadly consequentialist framework. From this perspective, the ultimate aim of public policy is to maximise utility, happiness, welfare, the satisfaction of preferences, or similar; and the behavioural aspect of public policy aims to harness a knowledge of human psychology to make this maximisation more effective. In particular, behavioural insights may be crucial to help policy-makers ‘save us from ourselves’ by helping citizens avoid falling into non-rational choices, for example, through framing effects, failures of will-power, and so on. But an alternative reading of the psychological literature is that human thoughts and actions are not biased from a rational standard, but are simply systematically inconsistent. If so, then utility and similar notions are not well defined either for individuals or as an objective of public policy. I argue that a different, contractarian viewpoint is required: that the determination of public policy is continuous with the formation of agreements we make with each other at all scales, from momentary social interactions, to linguistic and social conventions, to collective decisions by groups and organisations. Behavioural factors do not over-ride, but can (among many other factors) inform, our collective decision-making process. The point of behavioural insights in public policy is primarily to inform and enrich public debate when deciding the rules by which we should like to live.