Belief Closure : A Semantics of Common Knowledge for Modal Propositional Logic
The paper axiomatizes individual and common belief by means of modal propositional logic systems of varying strength. The weakest system of all just requires the monotonicity of individual belief on top of the axiom and rules of common belief. It is proved to be sound and complete with respect to a specially devised variant of neighbourhood semantiC's. The remaining systems include a K-system for each individual. They are shown to be sound and complete with respect to suitable variants of Kripke semantics. The specific features of either neighbourhood or Kripke semantics in this paper relate to the validation clause for common belief. Informally, we define a proposition to be belief closed if everybody believes it at every world where it is true, and we define a proposition to be common belief at a world if it is implied by a belief closed proposition that everybody believes at that particular world. This "fixed-point" or "circular" account of common belief is seen to imply the more standard "iterate" account in terms of countably infinite sequences of share beliefs. Axiomatizations of common knowledge can be secured by adding the truth axiom of individual belief to any system. The paper also briefly discusses game-theoretic papers which anticipated the belief closure semantics.
|Date of creation:||01 Oct 1993|
|Date of revision:|
|Contact details of provider:|| Postal: |
Fax: +32 10474304
Web page: http://www.uclouvain.be/core
More information through EDIRC
Please report citation or reference errors to , or , if you are the registered author of the cited work, log in to your RePEc Author Service profile, click on "citations" and make appropriate adjustments.:
- Ronald Fagin & Joseph Y. Halpern & Yoram Moses & Moshe Y. Vardi, 2003. "Reasoning About Knowledge," MIT Press Books, The MIT Press, edition 1, volume 1, number 0262562006, June.
- Bacharach, Michael, 1985. "Some extensions of a claim of Aumann in an axiomatic model of knowledge," Journal of Economic Theory, Elsevier, vol. 37(1), pages 167-190, October.
- Samet, Dov, 1990.
"Ignoring ignorance and agreeing to disagree,"
Journal of Economic Theory,
Elsevier, vol. 52(1), pages 190-207, October.
- Kaneko, Mamoru & Nagashima, Takashi, 1991. "Final decisions, the Nash equilibrium and solvability in games with common knowledge of logical abilities," Mathematical Social Sciences, Elsevier, vol. 22(3), pages 229-255, December.
- Monderer, Dov & Samet, Dov, 1989. "Approximating common knowledge with common beliefs," Games and Economic Behavior, Elsevier, vol. 1(2), pages 170-190, June.
- Modica, Salvatore & Rustichini, Aldo, 1999. "Unawareness and Partitional Information Structures," Games and Economic Behavior, Elsevier, vol. 27(2), pages 265-298, May.
- Paul Milgrom, 1979.
"An Axiomatic Characterization of Common Knowledge,"
393R, Northwestern University, Center for Mathematical Studies in Economics and Management Science.
- LISMONT, Luc & MONGIN, Philippe, 1994.
"On the Logic of Common Belief and Common Knowledge,"
CORE Discussion Papers
1994005, Université catholique de Louvain, Center for Operations Research and Econometrics (CORE).
- Lismont, L. & Mongin, P., . "On the logic of common belief and common knowledge," CORE Discussion Papers RP -1104, Université catholique de Louvain, Center for Operations Research and Econometrics (CORE).
- Robert J Aumann, 1999. "Agreeing to Disagree," Levine's Working Paper Archive 512, David K. Levine.
- John Geanakoplos, 1992. "Common Knowledge," Journal of Economic Perspectives, American Economic Association, vol. 6(4), pages 53-82, Fall.
When requesting a correction, please mention this item's handle: RePEc:cor:louvco:1993039. See general information about how to correct material in RePEc.
For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: (Alain GILLIS)
If references are entirely missing, you can add them using this form.