BCSSS

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.

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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.

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MECHANISM (Step) 2)

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"A mechanism showing a step function as its main characteristic" (W.R. ASHBY, 1960, p.91).

This term was suggested to ASHBY by J.C. WISDOM.

Systems endowed with a step mechanism are able to switch their behavior from one field of activity to another one. ASHBY explain this in the following way: "Suppose, in a state-determined system, that some of the variables are due to step-mechanisms, and that these are ignored while the remainder (the main variables) are observed on many occasions by having their field constructed. Then, so long as no step-mechanism changes value during the construction, the main variables will be found to form a state-determined system, and to have a definite field. But on different occasions different fields may appear" (p.94-5).

Ashby adds:

"If the system had contained two step-mechanism, each of two values, there would have been four fields of the main variables. In general, n steps-mechanism, each of two values, will give 2 fields. A moderate number of step mechanism may thus give a very much larger number of fields" (p.95).

So, step-mechanism in systems explain how they remain stable ("ultrastable in ASHBY's vocabulary) in a wide general deterministic sense, while however being able to adapt to a considerable range of variations, many times in a seemingly random way. Step-mechanism seem to open the way to heterogeneity and complexity.

For changes of field in an ultrastable system by switching at critical states through step-mechanisms, see ASHBY, 1960, p.96; figure 7/23/1.

Categories

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