International Encyclopedia of Systems and Cybernetics

The behavior typical of a system able to reproduce its own elements and their specific interrelations without any need for outside intervention (and even in spite of such interventions).

This behavior is typical of the living systems.

J BEDNARZ Jr. writes (1990, p.58): "Their specific mode of operation (organization) is not meant to be understood in terms of referring to something beyond itself – which would be the case with the introduction of the concepts of purpose, goal or function. Rather it is closed, referring constantly to itself through the alternate (re)production of components and complex of component-producing processes. Whatever takes place within them as living systems – whatever is accomplished by their organization – does so"… as necessarily and constitutively determined in relation to themselves because their being defined as unities through self-reference (is) their manner of autonomy" (quoted from R.H. HOWE & H.von FOERSTER, 1975, p.XIII).

Self-reference is also a characteristic of languages (as shown by this very work!). This may lead to well known paradoxical statements and contradictions. (crf. the famous case of EPIMENIDES, the Cretan, stating that all Cretans are liars). This problem has been finally eliminated by WIITHEHEAD's and RUSSELL's Theory of types, and also produced in systemics two successive very important offsprings: 2nd. order cybernetics (of the observer) and autopoiesis.

Some authors state that self-referential systems are "closed ". It should be understood that this means merely "organizationally closed": the system necessarily maintains numerous exchanges with its environment, but these do not affect its basic identity.

It is however to be noted that, in the words of N. LUHMANN (1995, p. 5): "…self-reference can only exists in an environment and only in relation to an environment. Or, with a different expression, that self-referential operations and system/environment differences mutually imply – and even more: logically imply each other".

And: "In the theoretical situation a new conceptual trinity sets new accents: it is the triad "autopoiesis, "operational closure", and "structural coupling". The concept of autopoiesis transfers the principle of self-reference from the structural to the operational level".

The system could not maintain itself without activity and its activity is in fact re-activity. It is experiencing with its environment through the "structural coupling" that feeds the autopoiesis of the system.

And, by the way, that saves it from entropic dissolution and /or solipsism