One of the distinctive features of Gerald Gaus’s public justification theory is his extensive use of the empirical data from the social sciences to support his normative claims. One such claim which stands out for its importance, within the context of Gaus’s theory, is the evolution of strong reciprocity: over time, members of large societies develop a tendency to follow social rules and punish defectors. This claim, in turn, is supported by several studies in experimental economics involving mixed motive games, which show how subjects are inclined to punish, even at a net cost for themselves, any perceived violation of social norms such as fairness. While critics of Gaus’s theory focused mainly on whether the use of empirical evidence in a normative theory is prima facie admissible, in this paper I address two different issues. The first concerns the accuracy of the empirical evidence used by Gaus’s theory, and whether the conclusions advanced by the social scientists on the grounds of this evidence are actually sound. The second issue, on the other hand, concerns the consistency between the empirical assumptions underlying these experiments and the claims of Gaus’s theory. I argue that both concerns are warranted. On the one hand, there is empirical evidence that the rule-following behavior observed in experiments involving mixed motive games is context dependent: the tendency of subjects to follow rules and punish defectors is strongly correlated to the epistemic constraints, such as anonymity, commonly imposed during the experiments. On the other hand, these constraints hardly reflect the circumstances of life in modern societies, which is the context assumed by Gaus’s justificatory theory. I conclude that Gaus’s account of rule-following punishers is not altogether invalidated, but the empirical evidence from experimental economics is insufficient to support it.
Key words: experimental economics, Gerald Gaus, naturalistic fallacy, public justification, social morality, ultimatum games.
