The Core of a Finite Exchange Economy: A Direct Proof of its Nonemptiness

The core of an economy consists of those states of the economy which no group of agents (coalition) can "improve upon". A coalition can improve upon a state of the economy if, by using the means available to that group, each member can be made better off. This paper presents the notion of the core in the framework of a pure finite exchange eonomy E and provides a direct proof of the nonemptiness of the core of E without considering the cooperative game which is traditionnaly associated to E.