Selective Contraction

Abstract Selective revision operators are well-known non-prioritized revision operators that allow for the acceptance of only part of the new information while rejecting the rest. In this paper, we introduce their contraction counterparts, which we refer to as selective contraction operators. These operators enable the removal of only part of the input information. As such, selective contractions can be viewed as a method for removing some of the beliefs that support the input belief without eliminating the belief itself. In this sense, selective contraction operators allow for a weakening of the input belief’s strength without discarding it. We provide representation theorems for various classes of selective contraction operators.