International Encyclopedia of Systems and Cybernetics

2nd Edition, as published by Charles François 2004 Presented by the Bertalanffy Center for the Study of Systems Science Vienna for public access.


The International Encyclopedia of Systems and Cybernetics was first edited and published by the system scientist Charles François in 1997. The online version that is provided here was based on the 2nd edition in 2004. It was uploaded and gifted to the center by ASC president Michael Lissack in 2019; the BCSSS purchased the rights for the re-publication of this volume in 200?. In 2018, the original editor expressed his wish to pass on the stewardship over the maintenance and further development of the encyclopedia to the Bertalanffy Center. In the future, the BCSSS seeks to further develop the encyclopedia by open collaboration within the systems sciences. Until the center has found and been able to implement an adequate technical solution for this, the static website is made accessible for the benefit of public scholarship and education.



"The subsystem at the perimeter of a system that holds together the components which make up the system, protects them from environmental stresses, and excludes or permits admission to various sorts of matter-energy and information"

This is J. MILLER's definition in his list of the 20 critical subsystems of any system (1978, p.3)

In B. BANATHY's words: "The boundaries of a system delimit the system space and set aside from the environment all those entities that make up the system" (1973, p.85)

K. BAUSCH describes boundaries as the "parametric conditions that delimits and define a system and set it apart from its environment"(Glossary- Personal communication)

The concept of boundary is basically ambiguous, in two different ways.

First, the boundary separates the system from its environment by defining what is inside and what is outside the system. In some cases however, it is difficult to distinguish precisely if some elements of the boundary belong to the system or to its environment… or to both.

Besides, the boundary does not define an absolute enclosure. It allows some specific inputs and outputs and bars others. It is selectively permeable.

In L. CARLSON-SABELLI and H. SABELLI's words: "Boundaries, when they exist, are interphases where opposites coexist, neither sharply delimited as in logic, nor simply gradual transitions, but actual areas of interchange and/or conflict, as illustrated by cellular membranes, and by national boundaries. The basins relative to two attractors, for instance, can penetrate each other in a manner which is topologically very complicated, rendering the outcome undetermined" (1992, p.681).

Furthermore, the boundary may be open or closed, in relation to the circumstances which affect the system and its environment.

T.F.H. ALLEN and T.B. STARR (1982, p.262) define the boundary as "a distinction made by an observer" and add: "Artificial boundaries are drawn arbitrarily and haphazardly. Natural boundaries are still arbitrary, but tend to be robust under transformation. That is, natural boundaries coincide for many distinct criteria".

Quoting G.H. GOODE and R.E. MACALL, G. P. SHCHEDROVITZKY writes "… boundaries pass over broad vague territories and the search for their precise position would elicit large but fruitless controversies" (1966, p.35)

These difficulties move G. WEINBERG to write: "Interface" is a more useful word than "boundary", for it reminds us to pay attention to the connection and not just the separation between system and environment" (1975, p.147)

Boundaries of physical systems are at the atomic or molecular level. In living systems they become organized as permeable membranes. In an organization they can be material enclosures as well as the behavioral result of abstract criteria of membership.


  • 1) General information
  • 2) Methodology or model
  • 3) Epistemology, ontology and semantics
  • 4) Human sciences
  • 5) Discipline oriented


Bertalanffy Center for the Study of Systems Science(2020).

To cite this page, please use the following information:

Bertalanffy Center for the Study of Systems Science (2020). Title of the entry. In Charles François (Ed.), International Encyclopedia of Systems and Cybernetics (2). Retrieved from www.systemspedia.org/[full/url]

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