Social consistency and individual rationality

Abstract

This paper aims at proving that social interactions can easily be rationalized by individual preferences as defined in standard microeconomic theory. For that purpose, we show individual choice rationality to be logically equivalent to social consistency, when individual rationality means that individual preferences are completely ordered and social consistency that there is a one-to-one mapping between a given family of social communities and the existence of a particular (unique, reflexive and symmetric) interaction relation between individuals. Moreover, continuity and monotonicity of individual preferences are shown to fit the modeling of group loyalty when group loyalty is defined as the ability to freely accept a personal loss for the global gain of a particular population.preferences ; social interaction ; communities ; group loyalty