The "second order cyberneticians" claimed that knowledge is a biological phenomenon (Maturana, 1970), that each individual constructs his or her own "reality" (Foerster, 1973) and that knowledge "fits" but does not "match" the world of experience (von Glasersfeld, 1987).
Systems science is generally said to have emerged during and after World War II, although there were precursors to the basic ideas. The people who created each school of thought were working largely independently, although many of them knew each other. They came from different disciplines, they were working on different problems, they formulated different variations of the principles of systems and cybernetics, and they often chose to affiliate with different academic societies.
A key location for the development of general systems theory was the University of Michigan’s Mental Health Research Institute (MHRI) where General Systems, the yearbook of the (SGSR) was based for many years. A mental health research institute may seem a peculiar place to find systems theory.
A group that was somewhat connected with general systems theory is usually associated with the term, the systems approach. They were located originally at the University of Pennsylvania. They later went to Case Western Reserve University and then back to the University of Pennsylvania. Their founding philosopher was E. A. Singer, Jr. One of Singer's students was C. West Churchman, and Churchman's first student was Russell Ackoff.
Another tradition in systems theory, known as system dynamics, originated at Massachusetts Institute of Technology. The founder of this tradition was Jay Forrester, a creative engineer who invented the magnetic core memory for computers and who built the , which is now in the Smithsonian Institution.
Another group at MIT and Harvard University developed the notion of “organizational learning.” Chris Argyris and Donald Schön were the key figures in this group. Argyris was a student of Kurt Lewin, who was a participant in the Macy Foundation meetings that were chaired by Warren McCulloch.