Doxastic Normality Logic: A Qualitative Probabilistic Modal Framework for Defaults and Belief

We propose a new semantics for modeling belief, mixing conncepts from qualitative probabilistic and classical possible world accounts. Our belief structures are coherent sets of qualitative plausibility measures and belief corresponds to truth in the most plausible worlds of each epistemic alternative. We provide an axiomatic characterization of these doxastic structures in a bimodal language, based on a belief modality and a default conditional, and present a corresponding new epistemic entrenchment logic.

• Type: Conference
• Year: 1996
• Where: LAI
• Authors: Emil Weydert
• Keywords: Belief Corresponds, Belief Structures, LAI 1996, Qualitative Plausibility Measures