Abstract
A social phenomenon called “power” is found out when an actor considers his decision as a selection which is directly ascribed to an intention of the other rather than a selection which is ascribed to his own intention. That is, when an actor considers his action as a selection of “selection following an intention of the other” this actor finds himself following power of the other. But why does a selection of an actor take a “bypass” via an intention of the other. The main purpose of this paper is to answer this question by giving a formal definition to power. We make it clear that power comes from dissociation between direct rationality depending on only actor's preference and indirect rationality through expecting the other's preference (or selection). At the same time we throw light upon the fundamental character by which we can discriminate two types of power: repressive power and incentive power. And we explain that power operates if both a man of power and a follower avoid a social state but the latter more so than the former.
