從 1950、60 年代受到政治學「行為主義革命」的影響，國際關係理論 開始嘗試建立科學的研究，「科學派」遂以「體系論」(system theory)進行 國際關係的理論化，國際關係的理論化也就成為國際體系的理論化。歷經 1960 年代只有少數國際關係學者關注國際體系理論的「相當低度發展的階 段」，1970 年代起逐漸有較多不同的學者都嘗試藉由其他學科(例如社會 學、生物學、控制學)學者的體系理論提出不同的「國際體系」理論化途 徑，1980 年代由新現實主義..

Following the behavioralism revolution of political science in the 1950– 60s, attempts for international relations(IR)theory to become scientific began with the theorization of IR through systems theory that engendered the theorization of international systems. Through an underdeveloped stage involved with only a few scholars in the 1960s, a contending stage with various approaches proposed in the 1970s, a dominated stage of neorealism in the 1980s, and to an opposite stage of constructivism and international historical..