摘要
Levesque’s logic of belief has a special modal operator O so that it is possible to saythat only a certain proposition(or finite of them)is believed.In this logic thenonmonotonic reasoning is captured by only using the classical notions of logic(satisfiability,validity,implication),while in other logics of belief such as Moore’sautoepistemic logic it is done using some definitions of new metalogical properties over
