An Update Semantics for Prima Facie Obligations
Leendert van der Torre, Yao‐Hua Tan · 1998
. The deontic logic dus is a deontic update semantics for prescriptive obligations based on the update semantics of Veltman. In dus the definition of logical validity of obligations is not based on static truth values but on dynamic action transitions. In this paper prescriptive prima facie obligations are formalized in update semantics. The logic formalizes the specificity principle, has reinstatement and does not have an irrelevance problem. Moreover, it handles the diagnostic problem by distinguishing between overridden, conflict and factual defeasibility. 1 The logic of norms Deontic logic is a modal logic in which Op is read as `p ought to be (done).' Deontic logic has traditionally been used by philosophers to analyze the structure of the normative use of language. In the eighties deontic logic had a revival, when it was discovered by computer scientists that this logic can be used for the formal specification and validation of a wide variety of topics in computer science (for ...