國際關係作為一門學科，其理論研究歷經多次大辯論，在第三次大辯論之後，學者引用實用主義（pragmatism）以規避國際關係理論第三次大辯論所引發的後設理論爭論（尤其是本體論與知識論的爭論）。歷經多年努力，實用主義已經在國際關係學術研討會、書籍與期刊成為一股新興的研究趨勢，有些學者稱之為「實用主義轉向」或是「意想不到的實用主義復興」。實用主義不僅影響整體的國際關係理論研究，也影響到國際關係建構主義理論內部的知識論爭論。源自實用主義哲學重視實務、強調多元、真理共識的知識論（a consensus theory of truth），有些建構主義學者（Friedrich Kartochwil、EmmuelAdler、Peter M. Haas 和Ernst B. Haas）意圖結合實用主義的知識論主張，而成實用建構主義的知識論，反對Alexander Wendt 的科學實存論觀點，強調回歸國際關係研究的基本，即是回歸「問題導向」的研究基本方向，並重視知識論與方法論的多元觀點，以實務（實踐）為先，發展務實的社會科學與國際關係，致使國際關係建構主義的知識論差異更受到關注。本文主旨在探索國際關係學者引入實用主義哲學學者（Charles Peirce、Williams James、John Dewey 和Richard Rorty）的知識論觀點，作為其國際關係理論的後設理論基礎，所呈現的知識論特質、相對優勢、研究方法與貢獻；
進而比較Friedrich Kartochwil、Emmuel Adler、Peter M. Haas 和Ernst B. Haas
等人的實用建構主義的知識論觀點，呈現其內部的異同；最後，探討實用建構主義理論研究的未來挑戰。

The history of international relations has been written in terms of “great
debates” among different theories. After the third great debate, researchers moved in a more pragmatic direction and away from the metatheoretical debates of the past,particularly epistemological and methodological controversy. After decades of effort,pragmatism emerged as a rising trend in the IR conferences, textbooks and journals.Some researchers havereferred to this as a “pragmatist turn” or “unexpected
renaissance of pragmatism”. Pragmatism has not only influenced international relations theory, but also has had an effect on the epistemological controversy within the international relations constructivism. Constructivists such as Friedrich Kartochwil, Emmuel Adler, Peter M. Haas, and Ernst B. Haas have claimed a pragmatic constructivism, incorporating pragmatism as an epistemological stance
against Alexander Wendt’s scientific realism.Pragmatic constructivism argues thatIR should get back to the basics, that is, back to question-driven orientations, an appreciation of different epistemological and methodological approaches, and an emphasis on practice. The aim is to develop a more practical science of international relations.This paper explores the philosophical pragmatism of Charles Peirce, Williams
James, John Dewey, and Richard Rorty. The paper examines their epistemological perspectives and pragmatism as a metatheoretic foundationfor pragmatic constructivism. It also discusses epistemological issues, the relative strengths, and methodological contributions of pragmatic constructivism. Finally, the paper looks at the future challenges forpragmatic constructivism.