In André Fuhrmann & Michael Morreau (eds.), The Logic of Theory Change. Springer (1991)
|Abstract||In earlier papers (Lindstrrm & Rabinowicz, 1989. 1990), we proposed a generalization of the AGM approach to belief revision. Our proposal was to view belief revision as a relation rather thanas a function on theories (or belief sets). The idea was to allow for there being several equally reasonable revisions of a theory with a given proposition. In the present paper, we show that the relational approach is the natural result of generalizing in a certain way an approach to belief revision due to Adam Grove. In his (1988) paper, Grove presents two closely related modelings of functional belief revision, one in terms of a family of "spheres" around the agent's theory G and the other in terms of an epistemic entrenchment ordering of propositions. The "sphere"-terminology is natural when one looks upon theories and propositions as being represented by sets of possible worlds. Grove's spheres may be thought of as possible "fallback" theories relative to the agent's original theory: theories that he may reach by deleting propositions that are not "sufficiently" entrenched (according to standards of sufficient entrenchment of varying stringency). To put it differently, fallbacks are theories that are closed upwards under entrenchment The entrenchment ordering can be recovered from the family of fallbacks by the definition: A is at least as entrenched as B iff A belongs to every fallback to which B belongs. To revise a theory T with a proposition A, we go to the smallest sphere that contain A-worlds and intersect it with A. The relational notion of belief revision that we are interested in, results from weakening epistemic entrenchment by not assuming it to be connected. I.e., we want to allow that some propositions may be incomparable with respect to epistemic entrenchment. As a result, the family of fallbacks around a given theory will no longer have to be nested. This change opens up the possibility for several different ways of revising a theory with a given proposition.|
|Keywords||AGM belief revision Grove, Adam incomparability entrenchment fallbacks|
|Categories||categorize this paper)|
|Through your library||Configure|
Similar books and articles
Edwin D. Mares (2002). A Paraconsistent Theory of Belief Revision. Erkenntnis 56 (2):229 - 246.
Hans Rott (2003). Basic Entrenchment. Studia Logica 73 (2):257 - 280.
Michael J. Shaffer (2002). Coherence, Justification, and the AGM Theory of Belief Revision. In Yves Bouchard (ed.), Perspectives on Coherentism. Editions du Scribe.
Adnan Darwiche & Judea Pearl (1997). On the Logic of Iterated Belief Revision. Artificial Intelligence 89:1-29.
Abhaya C. Nayak (1994). Iterated Belief Change Based on Epistemic Entrenchment. Erkenntnis 41 (3):353-390.
K. Britz (1999). A Power Algebra for Theory Change. Journal of Logic, Language and Information 8 (4):429-443.
Hans Rott (1992). Preferential Belief Change Using Generalized Epistemic Entrenchment. Journal of Logic, Language and Information 1 (1):45-78.
Sven Ove Hansson, Eduardo Leopoldo Fermé, John Cantwell & Marcelo Alejandro Falappa (2001). Credibility Limited Revision. Journal of Symbolic Logic 66 (4):1581-1596.
Abhaya C. Nayak, Paul Nelson & Hanan Polansky (1996). Belief Change as Change in Epistemic Entrenchment. Synthese 109 (2):143 - 174.
Added to index2009-07-23
Total downloads9 ( #122,367 of 722,780 )
Recent downloads (6 months)1 ( #60,541 of 722,780 )
How can I increase my downloads?