A Note on Prototype Revision Renata Wassermann, Eduardo Fermé Abstract: Belief revision deals with the problem of how to accommodate new assertions into an existent body of knowledge. Traditionally, the body of knowledge is represented by a belief set, a set of formulas closed under logical implication. A belief set can also be represented by the set of possible worlds where all its formulas hold. The idea of this paper is to apply methods developed in the context of belief revision in order to accommodate new information about concepts.