Summary: Pointwise Circumscription Revisited
Eyal Amir
Department of Computer Science,
Gates Building, 2A wing
Stanford University, Stanford, CA 94305­9020, USA
eyala@cs.stanford.edu
Abstract
A decade ago, Pointwise Circumscription was
proposed as a tool for formalizing common
sense. In this paper, we revisit some of its uses
and examine some cases in which it does not
yield the intended behavior. Specifically, we ex­
plore the cases in which unsatisfiability may re­
sult from the presence of multiple minimal mod­
els (for McCarthy's Circumscription). Then, we
present a form of circumscription, called Point­
Sensitive Circumscription, that is a generaliza­
tion of McCarthy's Circumscription and Lifs­
chitz's Generalized Pointwise Circumscription.
We illustrate how Point­Sensitive Circumscrip­

Source: Amir, Eyal - Department of Computer Science, University of Illinois at Urbana-Champaign

Collections: Computer Technologies and Information Sciences