Social Norms: Repeated Interactions, Punishment, and Context Dependence

Game-theoretic approaches to social norms have flourished in the recent years, and on first inspection theorists seem to agree on the broad lines that such accounts should follow.2 By contrast, this paper aims to show that the main two interpretations of social norms are at odds on at least one aspect of social norms, and both fail to account for another aspect. We are sympathetic to the broad project of using game theory to model social norms. Our aim is not to undermine this project or argue that no coherent framework or frameworks is possible in principle. Rather, we aim to show, with reference to two particular issues, that at this stage it is unclear if and how differing approaches can be integrated into a unified picture. The two issues we go on to discuss are, first, the role of punishment within the models and, second, how they deal with the context dependence of norm triggering. In each case it is the question of whether or not the model should be one of repeated or one-shot interactions that is the source of problems for integration. When it comes to different modelling approaches, the recent literature provides two presentations of social norms. Ken Binmore outlines a model that frames social norms in terms of repeated interactions (1994, 1998, 2005). In contrast, Cristina Bicchieri’s model is of one-shot interactions and involves utility transformations, triggered by social context, that make norm conformity the rational behaviour (2006, 2008). Both of these authors repeatedly refer to each other’s work as belonging to a common programme but, we argue, their difference on the question of repeated interaction models makes integration of their approaches problematic. We draw attention to the fact that differences on the question of whether we should think in terms of repeated encounters or not lie at the very foundations of the models. Such disagreement makes common approaches to punishment and context dependence deeply problematic. This is not to say that having multiple approaches is unwelcome in principle. Still, those unfamiliar with the literature could be forgiven for taking it that there are core similarities common to all game theoretic treatments of social norms. In