International System

The international system is made up of individual, constituent units and an ordering principle that arranges the structure of those units, together forming a whole toward an outside environment. [Page 1323]A third defining characteristic of the international system is the interaction that continuously occurs between the level of the individual units and the overall structural level. This notion, comprising three basic elements (units, structure, and unit–structure interaction), suffices to describe a limited, structural conceptualization of the international system. An alternative definition that also encompasses the connections between the units (units, structure, unit–structure interaction, and unit–unit relations) may be referred to as a broader, relational conceptualization of the international system. The use of the concept, in either version, is justified as soon as the system exhibits properties that individual units do not.

After a brief note on the intellectual heritage of the concept of the international system, this entry offers a discussion of four sets of issues found pertinent to the subject in contemporary political science and international relations scholarship. The four sets of issues that will help elucidate key aspects of the concept of the international system are (1) the properties of units and structure; (2) its origins and historical evolution; (3) understandings of change, transformation, and breakdown; and (4) the inherent potential and limitations of the concept.

When it comes to the basic figure of thought, it can be argued that some idea of an international system was envisaged in the Amarna letters of ancient Egypt during the Late Bronze Age and is implicit in the classical writings of Thucydides, Kautilya, Sun Tzu, and others who commented on the subjects of diplomacy, trade, and war. Several of these authors described periods of rather intense interaction between political units and a wider political or economic structure, outside of which there was significantly less such interaction. The international system, however, is a concept that emerged in the early-modern era in the treatises of prominent lawyers and philosophers. Following in the footsteps of Jean Bodin, Hugo Grotius, and Thomas Hobbes and their respective works on sovereignty, state equality, and political order, Samuel Pufendorf explicitly referred to the states system as several states that are connected as to seem to constitute one body but whose members retain sovereignty. During the 20th century, the rise of new academic disciplines made its mark on all concepts containing the component “system,” and structuralist authors of organicist, process-oriented, or functionalist persuasion subsequently applied systems theories to virtually all branches of the nascent social sciences. Arguably, this intellectual trend had a profound effect on the academic field of international relations.