Computing the Extensions of Autoepistemic and Default Logics with a Truth Maintenance System

In this paper we develop a proof procedure for autoepistemic (AEL) and default logics (DL), based on translating them into a Truth Maintenance System (TMS). The translation is decidable if the theory consists of a finite number of defaults and premises and classical derivability for the base language is decidable. To determine all extensions of a network, we develop variants of Doyle's labelling algorithms.