Impossibility results for belief contraction

  • Sven Ove HanssonEmail author
Open Access


Three seemingly weak and plausible conditions on an operation of contraction on belief sets are shown to be logically incompatible: (1) there is at least one sentence that can be successfully removed by the operation, (2) both the original belief set and the outcome of the operation have finite representations, and (3) a non-tautologous sentence can be removed without loss of all its non-tautologous logical consequences.


Belief change Contraction Eradication Success postulates Finite-based outcome 

Mathematics Subject Classification (2010)




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Authors and Affiliations

  1. 1.Kungliga Tekniska HögskolanStockholmSweden

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