同一性替换规则在内涵语境中失效的诠释

Cognitive Interpretation of the Invalidity of the Law of Substitution of Co-referential Expressions in Intensional Contexts

经典逻辑中的同一性替换规则在内涵语境中普遍失效,产生"内涵困惑"。本文围绕命题态度动词构成的内涵语境,分析并评价以弗雷格和罗素等为代表的分析性语言哲学家对"内涵困惑"的解决方案,指出"内涵困惑"的解决应该把命题态度主体的认知结构考虑在内;只有当命题态度主体对替代的两个指称表达式同一也具有相当程度的认知时,同一性替换规则才能在内涵语境中有效。

The law of substitution of co-referential expressions, which originated from classical logic, is invalid in intensional contexts, hence ＂intensional puzzle＂. Centering around intensional contexts composed of verbs of propositional attitude, this paper first analyzes and evaluates the respective solutions by Frege and Russell, and then points out that the solution to ＂intensional puzzle＂ should take into consideration the cognitive structure of the agent of the verbs of propositional attitude, that is, the law of substitution of co-referential expressions won＇ t be valid until the agent has the knowledge to a proper degree that two expressions undergoing substitution are the same.