We present a general, consistency-based framework for belief change. Informally, in revising K by , we begin with and incorporate as much of K as consistently possible. Formally, a knowledge base K and sentence are expressed, via renaming propositions in K, in separate alphabets, but such that there is an isomorphism between the original and new alphabets. Using a maximization process, we assume that corresponding atoms in each language are equivalent insofar as is consistently possible. Lastly, we express the resultant knowledge base using just the original alphabet. There may be more than one way in which can be so extendedby K: in choice revision, one such "extension" represents the revised state; alternately revision consists of the intersection of all such extensions. The overall framework is flexible enough to express other approaches to revision and update, and the incorporation of static and dynamic integrity constraints. Our framework differs from work based on ordi...
James P. Delgrande, Torsten Schaub