A Theory of Choice under Internal Conflict

In this paper we argue, inspired by some psychological literature, that choices are the outcome of the interplay of diff erent, potentially conflicting motivations. We propose an axiomatic approach with two motivations, which we assume to be single-peaked over a certain given dimension. We first consider the case in which motivations are given and stable, and then introduce the possibility for motivations to change. We show first that in the no-motivation change case, certain choice behaviours that appear to be inconsistent from the standard rational choice point of view may be explained in our framework as the outcome of conflicting motivations. Afterwards, in the case of motivation change, we present two psychologically-flavoured assumptions about how motivations are influenced by choices. We show that, with some additional weak assumptions of rationality, motivation change leads to a smaller range of potentially inconsistent choices and not to a larger one as one may think. In particular, conflicts between two motivations can eventually be resolved by choosing di fferent actions and consequently a definite and final preference for an action be revealed.