The goal of this paper is to construct a user-friendly model of unawareness. We start from an axiom system (in first-order modal logic) that enables us to express the following kinds of sentences: “the agent is not sure whether or not there is anything that he is unaware of”, and “I am not...

For agents with identical homothetic preferences (but possibly different endowments), aggregate excess demand can be derived from maximization of a utility function of a representative agent whose endowment is the sum of the individual's endowments. Such an economy has a unique equilibrium. In...