Possibilistic Logic
D. Dubois, Jérôme Lang, Henri M. Prade · 1994
Abstract Possibilistic logic is a logic of uncertainty tailored for reasoning under in-complete evidence and partially inconsistent knowledge. At the syntacticlevel it handles formulae of propositional or first-order logic to which are attached numbers between 0 and 1, or, more generally, elements in a to-tally ordered set. These weights are lower bounds on so-called degrees of necessity or degrees of possibility of the corresponding formulae. The de-gree of necessity (or certainty) of a formula expresses to what extent the available evidence entails the truth of this formula.