Some logics of belief and disbelief

  title={Some logics of belief and disbelief},
  author={Samir Chopra and Johannes Heidema and T. Meyer},
The introduction of explicit notions of rejection, or disbelief, in logics for knowledge representation can be justified in a number of ways. Motivations range from the need for versions of negation weaker than classical negation, to the explicit recording of classic belief contraction operations in the area of belief change, and the additional levels of expressivity obtained from an extended version of belief change which includes disbelief contraction. In this paper we present four logics of… 
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