Possible Worlds And Individual Essence

With the advancement of modern logic technology,scholars have established different modal logic systems,but these systems have been widely criticized for lack of a solid semantic foundation for a long time.Although the possible world semantics theory with ’ accessibility relation’ as the core is helpful to respond to the above criticism,it faces the unavoidable problem of individual trans-world identity : whether individual trans-world is the same and how to identify it.In view of this,on the basis of expounding the problem of trans-world identity and clarifying the relationship between two different trans-world individuals,this paper deeply analyzes the difficulties existing in the problem of trans-world identity,and gives a feasible essentialist solution to the problem of trans-world identity.Specifically,there are the following aspects :On the basis of combing the diachronic development of modal logic and possible world semantics,the first chapter analyzes the correlation between possible world semantics interpretation and trans-world identity.The second chapter introduces the ontological views of modal realism and moderate modal realism and their trans-world individual relations.The modal realism advocates that the possible world is a concrete reality,and the corresponding bodies of different worlds are similar.Moderate realism holds that the possible world is only the possible state of the world,and there is no real boundary.In this regard,the trans-world individual is identical.The third chapter analyzes the difficulties in the problem of trans-world identity.First,explain the dilemma of finding the individual essence or recognizing the ’ bare identity ’revealed by the ’ Chisholm paradox ’;secondly,it introduces the technical work of Marcus,Forbes and Fine to explain and dispel de re modality through quantifier substitution,trying to solve the problem of trans-world identity from the root.The fourth chapter explores the feasible essentialist solutions to the problem of transworld identity.Firstly,Quine ’s challenge is answered by distinguishing proper names from descriptions to ensure individual identity.On this basis,the difference between traditional essentialism and modal essentialism is clarified.Secondly,based on the framework of possible world theory,by comparing the similarities and differences between the possible world ontology and individual essence of modal realism and moderate realism,the standard of reasonable individual essence scheme is identified.Thirdly,on the basis of analyzing the problem of possible world philosophy,following the three principles of ontology economy,conforming to intuition and providing reasonable semantic interpretation semantics for modal logic,this paper advocates an improved moderate realism view and puts forward the identity standard of trans-world individuals-relational essence.