在國際關係的研究領域中，不論是國家中心論或是以體系為主的體系理論，都以國家為研究的客體。伴隨著全球化浪潮，「全球治理」概念的出現，表明以國家為主的國際政治體系已無法解決國際環境的複雜變化，須藉助許多跨國性次級團體來共同治理。有鑑於此，新現實主義、新自由主義、 與建構主義中以國家為給定對象的國際關係主流理論，遇到解釋上的局限， 需要建構一套新的本體論與知識論，俾有效解釋在國際政治中逐漸呈現的多元行為體治理現象。本文認為國際關係理論面臨三個問題的挑戰:一、如何解釋國際政治多元行為體的現象?二、如何解釋行為體的認同變化與行動選擇?三、如何解釋人、多元行為體與國際社會三者相互建構的關係?本文援引當代社會理論，將「主題」與「個人」視為來回往返的主客體，以「主題」取代「國家」成為主體，並以「權力載體」的概念取代行為體，嘗試對上述問題做出合理的系統性解釋。本文認為，一旦主題成為社會共識，個人會依所處的社會位置與知識理念，選擇適當的「權力載體」，創造出符合系統目標的論述，而在論述的競合中，社會的建構於焉發生。

Theories of international relations(IR), whether through state-centric or systemic approach, put states as centers of research objectives. With trending globalization, the advent of the global governance concepts manifests that a state-focused international political system without transnational sub-political groups has failed to respond to complex changes in the international environment. Accordingly, this challenges neo-realism, neo- liberalism, and constructivism, which focus on the state-centric approach and experience explanatory constraints. In order to interpret the multiple actors’ phenomenon in present international politics, a set of new ontology and epistemology in the study of IR should be introduced. The aforementioned theories exhibit some explanatory shortcomings with regards to(1) multiple actors’ phenomenon in present international politics;(2)actor’s identity shifting and its alternatives of action;(3)the co-constructive relationships among individuals, multiple actors, and the international society.