Assertional Default Theories

The research reported in this paper was originally motivated by some defects in Reiter's DL. A first solution, CDL, solved the problems but introduced a new one, the floating conclusions problem. We therefore developed a new default logic, CDL*, which is distinct from CDL in the following respects: assertions with multiple supports are admitted one single set of credulous beliefs containing all CDL-extensions is defined inductively skeptical derivability is defined in a new way.