达米特的演绎辩护思想

On Dummett’s Justification Thought of Deduction

达米特区分了演绎辩护问题的三个层次:演绎论证的句法有效性的辩护、演绎逻辑系统的正确性的辩护以及演绎推论如何可能的辩护。第一层次的演绎辩护不存在问题。就第二层次的辩护而言,分子论语言观是其语言哲学前提,从基于分子论语言观的意义理论出发,借助于可靠性或完全性的语义学证明,可以构造一个演绎逻辑系统的正确性的辩护。第三层次的演绎辩护问题主要是演绎推论的有用性的辩护,它要求以承认真与真的认识之间存在某种程度的间隙的意义理论为基础。彻底的实在论的意义理论所允许的这种间隙过大,难以说明语言理解和语言学习;而彻底的观念论意义理论所允许的这种间隙又过小。达米特认为,解决第三层次演绎辩护问题所需的意义理论,就真与真的认识的间隙而言,它应比彻底的实在论的意义理论小,而应比彻底的观念论的意义理论大。达米特的演绎辩护思想揭示出意义理论对于现代逻辑的重要影响。

According to Dummett,the issues about the justification of deduction have three levels: the first is the justi fication of the validity of an argument,the second is the justification of the correctness of a whole logic system,and the third is the justification of how deductive inference is possible.A molecular view of language is the ba sis of the justification thought of deduction.From a theory of meaning which based on it,we can provide the justification of the correctness of a whole logic system,by constructing a proof of reliability or completeness.The third is mainly on the justification of the usefulness of deductive inference,and it can be tracked with a mean ing theory which admits the gap between the truth and the recognition of truth.This correct theory can be nei ther unreservedly idealist nor unreservedly realist;it must allow another gap between the truth and the recogni tion of truth,which is rather than a classically idealist theory,but less than a classically realist theory.Mr.Dummett’s thought on the justification of deduction show us the influence of meaning theory on modern logic.