2011/08/16 by Marc Denecker, Denecker, Marc, Victor W. Marek +3
Computer Science · #Artificial Intelligence (cs.AI) #FOS: Computer and information sciences #I.2.4 #Logic, Reasoning, and Knowledge #Logic, programming, and type systems #Multi-Agent Systems and Negotiation #Semantic Web and Ontologies
paper · pdf · doi:10.48550/arxiv.1108.3278
openalex publication_date 2011/08/16 · openalex created_date 2025/10/24 · openalex updated_date 2026/07/28
A fact apparently not observed earlier in the literature of nonmonotonic\nreasoning is that Reiter, in his default logic paper, did not directly\nformalize informal defaults. Instead, he translated a default into a certain\nnatural language proposition and provided a formalization of the latter. A few\nyears later, Moore noted that propositions like the one used by Reiter are\nfundamentally different than defaults and exhibit a certain autoepistemic\nnature. Thus, Reiter had developed his default logic as a formalization of\nautoepistemic propositions rather than of defaults.\n The first goal of this paper is to show that some problems of Reiter's\ndefault logic as a formal way to reason about informal defaults are directly\nattributable to the autoepistemic nature of default logic and to the mismatch\nbetween informal defaults and the Reiter's formal defaults, the latter being a\nformal expression of the autoepistemic propositions Reiter used as a\nrepresentation of informal defaults.\n The second goal of our paper is to compare the work of Reiter and Moore.\nWhile each of them attempted to formalize autoepistemic propositions, the modes\nof reasoning in their respective logics were different. We revisit Moore's and\nReiter's intuitions and present them from the perspective of autotheoremhood,\nwhere theories can include propositions referring to the theory's own theorems.\nWe then discuss the formalization of this perspective in the logics of Moore\nand Reiter, respectively, using the unifying semantic framework for default and\nautoepistemic logics that we developed earlier. We argue that Reiter's default\nlogic is a better formalization of Moore's intuitions about autoepistemic\npropositions than Moore's own autoepistemic logic.\n