摘要 詹姆士的實用主義真理理論自發表以來即飽受爭議。本文旨在說明，他 的真理理論的目的並非是要提出一個「真理」的新定義，而是在同意於「真 理符合實在」的同時，從人類活動的實踐層面來釐清「符合」與「實在」這 兩個詞的意義；他所指的「實在」能對個體之信念系統行使強制影響力；他 的真理理論的原型就是他對於「新意見如何在一個體的信念系統中被接受」 的整體論主張，而相似的主張可見於日後蒯因所寫之著名的〈經驗主義的兩 個教條〉的最後一節。本文分為兩部份，第一部份是從詹姆士的「三重實 在」的主張出發來闡釋他的「真理」觀念；接著在第二部份應用第一部份所 獲得之成果來闡釋從他的《實用主義》挑出之五個有關「真理」之受到爭議 的段落。

Abstract William James’s pragmatic theory of truth has been controversial ever since its publication, and is dismissed by some philosophers as seriously defected. This paper aims to do justice to it by means of elucidating James’s view of the dynamical relation between opinions taken as true and what he calls “threefold realities” in an individual’s system of beliefs. The first part of this paper shows that his theory of truth aims not to give a new definition of “truth,” but to clarify, from the broadly practical perspective of human activity, the meanings of “agreement” and “reality” in the definition that truth agrees with reality, which James accepts; that he holds that threefold realities can exert coercive influence on an individual’s system of beliefs; and that the archetype of his theory of truth is his holistic view of how a new idea comes to be accepted in an individual’s system of beliefs, which anticipates what is maintained in the last section of Quine’s well-known “Two Dogmas of Empiricism.” The second and last part of this paper pursues the task of clarifying, by applying the theses presented in the first part of this paper, five paragraphs quoted from his Pragmatism which are rather puzzling at first sight.