G?rdenfors's Impossibility Problem:A New Solution

Based on the belief change theory of G?rdenfors and the causal relationship of the Ramsey test to derive the G?rdenfors' s Impossibility Problem is main lines,with the belief change theory,a detailed analysis of the root causes,manifestations and existing solutions of the G?rdenfors' s impossibility problem,and a new scheme to solve the impossibility theorem is proposed——F program.Based on the above,the article argues that G?rdenfors belief change theory essentially solves certain ontological acceptability problems and also gives a system that can formally describe the problem;The Ramsey test is the basis of reasoning which provides a conditional sentence as a link to the belief change theory.Because of the meaningful lack of Ramsey test in the process of transforming from object language to formal language,and the process of eight formulas for belief correction to derive other inferences,the process of "certain laws" is lack from the process of formal language to object language conversion,and leads an inconsistent conclusion.The main part of this article is three chapters.In the first chapter,it briefly analyzes the diachronic history,which is from the research background of conditional sentences to the belief change theory.Then it analyzes in detail the basic formula,the form and proof of the public opinion and inference of G?rdenfors' s belief change theory,and compares and analyzes the original text of the Ramsey test,and the various versions.The second chapter,it detailed analyzes and explains,Lindstrom and Rabinowicz three different solutions to the G?rdenfors' s Impossibility Problem,and under the premise of comparison,analyzes whether the various solution fundamentally solves the G?rdenfors' s Impossibility Problem.In the third chapter,the article starts from the philosophical,semantic and formal levels,and analyzes the reasons and results of the incompatibility between belief correction and Ramsey test.Based on this,a solution to the problem--F scheme is proposed.Solving the G?rdenfors Impossibility Problem,in a sense,not only promotes the "certain laws" of conditional sentence analysis and judgment,but also helps to improve the belief change theory and promote the improvement of AGM theory.Furthermore,the application of belief change theory can avoid this problem in the fields of intelligent learning,intelligent reasoning,conditional sentences and non-monotonic reasoning in the field of belief change.