Results on translating defaults to circumscription

摘要

In this paper we define different concepts of translating a set of defaults into circumscription. The most important of these, modular translation, requires that additive changes of specific facts (not defaults) of default theory translate to additive changes of the simple abnormality theory (corresponding to circumscription). We show that, surprisingly enough, an important class of defaults, normal defaults with prerequisites, does not have such a modular translation into circumscription (abnormality theory). We also establish the classes of defaults which are translatable into circumscription.