Systems theory is a multidisciplinary approach to the study of an abstract organization. While the term remains largely vague within academia, it attempts to investigate phenomena that are common to complex systems as well as create mathematical models in order to describe them. The origins of systems theory date to the 19th century, and can be found in the thought of both Marx and Darwin.
The immediate antecedent of systems theory comes from the work of biologist Ludwig von Bertalanffy, who developed General System Theory in the 1950s. Bertalanffy believed that many biological phenomena were open systems, a system that has a border permeable to both input and output.
Systems theory holds that any system will contain four elements. The first part are objects, either physical or abstract, or both. The second part is attributes, the properties of the system and its various objects. Third are internal relationships between objects. The fourth quality is that the system exists in an environment. A final definition of system is a set of objects that affect one another within the environment in order to create a larger pattern, one that is different than the parts. Systems must continually engage in input and output with the environment.
Systems theory has found application in wide range of disciplines, including biology, engineering, and psychology. Cybernetics, the study of communication and feedback in a system, is an important and growing field developed out of systems theory.