Of Fruitcakes and Patriot Games, Essay

Abstract

This is a critical review essay regarding Eric Posner's theory of social norms. In his book, Law and Social Norms, and elsewhere, Posner articulates and defends a signaling theory of social norms or, in Posner's terms, "nonlegal mechanisms of cooperation." According to Posner, social norms allow parties to solve a particular sort of repeat prisoner's dilemma that describes a general condition of putatively cooperative behavior. On Posner's model, compliance with a norm is said to signal that one is a good cooperative partner because it signals that one has a low discount rate. I argue that, although much is interesting in Posner's discussion, the theory is inadequate to the task. Repeatedly, it appears that the cost structure of the signals in question cannot be right - the signals coming too cheap or too dear - if signaling can, qua rational choice theory, explain the norms in question. That appearance is all we have to go by, because the model does not generate adequately specific predictions to be testable. I argue that Posner's diverse collection of norms is not likely to describe a natural kind. I also suggest that, although there is a signaling element to many cases of norm compliance, certain core examples of social norms serve important non-signaling functions as constraints on human behavior. Certain norms are useful because, among other things, they lower the cost of socially beneficial behavior.

Keywords: Social norms, extralegal constraints on behavior, Eric Posner, signaling, cooperation, game theory, prisoner's dilemma