Abstract: Let Г be finite theory，this paper discusses the consistency of Г in different n-valued propositional logic L_n^* firstly，then the theory of Г-reduction in n-valued propositional logic L_n^* is introduced.Several ways to determine the Г-reduction are studied by investigating the relationship between Г and their subsets since there has a formal multi-valued formal context deduced by the finite theory Г.

摘要： 设Г为有限命题集，首先讨论了Г在不同的n值命题逻辑系统L_n^*中的相容性问题，提出了Г的约简理论，从命题集Г所诱导的多值形式背景出发，运用概念格的方法从Г及其子集的关系出发给出了Г约简的判定定理。