Questionable Patterns of Change
This chapter explores some of the problematic properties of the standard (AGM) operations of change. Both contraction and revision violate the highly plausible postulate of finite-based outcome. Contraction has further problems relating to the postulates of success, recovery, and inclusion, and revision has implausible monotonicity-related properties. Additional problems arise when the framework is extended to include conditional sentences and iterated change. The chapter concludes with a list of ten desiderata for an alternative approach to belief change that eschews the major problems exhibited in this and the previous chapter.