开放逻辑中一类算子的不动点

Fixed Points of Some Operators in Open Logic

在开放逻辑中，令Γ为一假说，Ａ为一句子，对任何Γ到Γ的幂集合的一个映射ｆ本文定义了如下算子△ｆ，对任何，且．我们讨论了算子△ｆ的不动点的一些性质及其与Ｒ－重构的关系。

In this paper we define operators △_f for all functions f from Г to the power set of Г by △_F(S)= {X∈Г|S A and {X} U (S-f(X) A} for all SГ,where Г is a hypothesis,A is a sentence such that Г and A is rejected by facts in open logic. We have discussed the properties of the fixed points of △_f and their relations to R-reconstructions of Г for the rejection of A by facts.