MP(superscript M) is a 3-valued logic propositional calculus system which is based on the medium logic system, and it is used to deal with the incomplete information in the database.

• 摘要MP(上标M)系统是在中介逻辑系统的基础上建立起来的，用于处理数据库中不完全信息的三值逻辑命题演算系统。