[General system therapy--considerations on a universal therapy theory and its use on psychotherapy practice].

The cybernetic model of interaction of the early system therapy was derived from the concept of feedback mechanisms. It is based upon the assumption that living beings interact with each other as open systems and thereby exchange information. The model can easily be used for the description and explanation of the therapeutic interactions in all schools of psychotherapy, but it is very abstract. In contrast, in the biosystem theory of Maturana living beings as autopoietic systems are operationally and cognitively closed. Exchange of information among them is not possible. Together with the so-called "radical constructivism" this theory has increasingly influenced system therapy over the past ten years and stimulated the development of an alternative model by which the interaction between therapist and client can be described differently and explained in a new way. The model does not only allow the pragmatic integration of all methods of psychotherapy, but also the design of a therapeutic approach including all schools, which is roughly sketched here and called "general system therapy".