要探究國際關係建構主義理論的學術貢獻與影響，實有必要回歸到其肇 始之初的系絡，即是Nicholas Onuf與Friedrich Kratochwil的學術生涯發展之 中，由於Onuf 和Kratochwil 所受的國際法與國際關係學術訓練，致使他們 致力於以社會理論連結國際關係理論與國際法。國際關係建構主義理論也就 是肇始於他們兩人的此連結當中，進而逐漸擴展成為國際關係重要的理論或 研究途徑。 本文的主旨在比較分析Onuf 與Kratochwil 的社會理論（建構主義）在 連結國際關係理論與國際法學理論的方式，以理解國際關係建構主義理論的 社會理論意涵，而能探索Onuf 和Kratochwil 在國際關係與國際法的連結及 貢獻。首先，以Onuf 訪台的三場演講呈現此連結為其學術的志業；其次， 比較Onuf、Kratochwil 和Wendt 的理論觀點差異，以顯示Onuf 和 Kratochwil 兩人的相近與Wendt 相異；第三，論述兩人在促進建構主義理論 發展的貢獻，以說明建構主義理論成為國際關係與國際法重要理論的原因； 第四，比較兩人在國際法理論與國際關係理論之間的差異，藉以說明兩者的 建構主義理論化過程並未以批判的方式思考其法律的意涵，而是假定了既有 體制的正當性。第五，比較兩人在社會理論的差異，藉以理解兩人的建構主 義社會理論內容；第六，比較兩人的建構主義哲學基礎差異，探索兩人運用 建構主義理論連結國際法與國際關係差異的關鍵；第七，以整體比較兩人之 間的連結差異；第八，就兩人與國際關係與國際法的連結，提出其所受到的 批評與影響。

To explore contributions and influences of constructivism, we should trace back to the career developments of Nicholas Onuf and Friedrich Kratochwil. Due to their trainings of International Law （ IL ） and International Relations（IR）, they have focused on linking IR and IL with constructivism as a social theory. Constructivism originated from this linkage and had become an important theory or approach in IR. This article comparatively explores the way of linking IR and IL with social theory（constructivism）in Onuf’s and Kratochwil’s works, in order to understand the implications of constructivism and its contributions to IR and IL. First, we present Onuf’s three speeches when he visited Taiwan in 2012 that portray his academic vocation. Second, we analyze different perspectives amongst Onuf, Kratochwil and Wendt to show a similarity between Onuf and Kratochwil, and dissimilarity from Wendt. Third, we discuss their contributions in advancing constructivism and explain reasons for constructivism being a major theory in IR and IL. Fourth, we compare the differences between Onuf and Kratochwil in IL and IR and show that their theorizations of constructivism has been achieved by assumptions of legitimacy of the establishments and not through critical thinking of international laws. Fifth, we compare their differences in constructivism as a social theory in order to understand their perspectives. Sixth, we compare their differences in the philosophical foundations of constructivism and explore their different ways of linking IL and IR. Seventh, we compare their total linkages for integral understanding. Finally, we present critiques from IL and IR and discuss their influences on IL and IR.