Action Theory Contraction and Minimal Change

Proceedings of the 11th Conference on Principles of Knowledge Representation and Reasoning (KR'08)This work is about changing action domain descriptions in dynamic logic. We here revisit the semantics of action theory contraction, giving more robust operators that express minimal change based on a notion of distance between models. We then define syntactical contraction operators and establish their correctness w.r.t. our semantics. Finally we show that our operators satisfy the PDL-counterpart of the standard postulates for theory change adopted in the literature