Editing Open system (systems theory)

{{Short description|Systems with external interactions}}
{{Use American English|date = March 2019}}
[[File:OpenSystemRepresentation.svg|thumb|252px|''Open [[system]]s'' have input and output flows, representing exchanges of matter, energy or information with its surroundings.]]

An '''open system''' is a system that has external interactions. Such interactions can take the form of information, energy, or material transfers into or out of the system boundary, depending on the discipline which defines the concept. An open system is contrasted with the concept of an [[isolated system]] which exchanges neither energy, matter, nor information with its environment. An open system is also known as a flow system.

The concept of an open system was formalized within a framework that enabled one to interrelate the [[Organismic theory|theory of the organism]], [[thermodynamics]], and [[Theory of Evolution|evolutionary theory]].<ref>Luhmann, Niklas. ''Social Systems''. Stanford: Stanford University Press, 1995; pp. 6-7</ref> This concept was expanded upon with the advent of [[information theory]] and subsequently [[systems theory]]. Today the concept has its applications in the natural and social sciences.
[[File:Diagram Systems.svg|thumb|253x253px|Properties of isolated, closed, and open systems in exchanging energy and matter.]]
In the [[natural sciences]] an open system is one whose border is permeable to both [[energy]] and [[mass]].<ref>[http://www.maxwellian.demon.co.uk/faq/glossary.html Glossary] {{Webarchive|url=https://web.archive.org/web/20070817185842/http://www.maxwellian.demon.co.uk/faq/glossary.html |date=2007-08-17 }} Maxwell Demon, 1998.</ref> By contrast, a [[closed system]] is permeable to energy but not to matter. 

The definition of an open system assumes that there are supplies of energy that cannot be depleted; in practice, this energy is supplied from some source in the surrounding environment, which can be treated as infinite for the purposes of study. One type of open system is the [[radiant energy]] system, which receives its energy from [[solar radiation]] &ndash; an energy source that can be regarded as inexhaustible for all practical purposes.

==Social sciences==
In the [[social sciences]] an open system is a process that exchanges material, energy, people, capital and information with its environment. French/Greek philosopher [[Kostas Axelos]] argued that seeing the [[world-systems theory| "world system"]] as inherently open (though unified) would solve many of the problems in the social sciences, including that of [[Praxis intervention |praxis]] (the relation of knowledge to practice), so that various social scientific disciplines would work together rather than create monopolies whereby the world appears only sociological, political, historical, or psychological. Axelos argues that theorizing a closed system contributes to ''making'' it closed, and is thus a conservative approach.<ref>Axelos, K. ([2006] 1984). "The World: Being Becoming Totality," from ''Systematique ouverte'' (Trans. Gerald Moore, Les Editions de Minuit: Paris). ''Environment and Planning D: Society and Space,'' Vol. 24, 643-651.</ref>{{qn|date=June 2021}} The [[Louis Althusser|Althusserian]] concept of [[overdetermination]] (drawing on Sigmund Freud) posits that there are always multiple causes in every event.<ref>Althusser, L. ([2005] 1969). ''For Marx.'' London: Verso Books, Ch. 3: "Contradiction and Overdetermination," [http://www.marxists.org/reference/archive/althusser/1962/overdetermination.htm].</ref>

[[David Harvey (geographer) |David Harvey]] uses this to argue that when systems such as [[capitalism]] enter a phase of crisis, it can happen through one of a number of elements, such as gender roles, the relation to nature/the environment, or crises in accumulation.<ref>RSA Animate - David Harvey, The Crises of Capitalism: [https://www.youtube.com/watch?v=26o22Y33h9s].</ref> Looking at the crisis in accumulation, Harvey argues that phenomena such as [[foreign direct investment]], [[privatization]] of state-owned resources, and [[accumulation by dispossession]] act as necessary outlets when capital has overaccumulated too much in private hands and cannot circulate effectively in the marketplace. He cites the forcible displacement of Mexican and Indian peasants since the 1970s and the Asian and South-East Asian financial crisis of 1997–8, involving "hedge fund raising" of national currencies, as examples of this.<ref>Harvey, D. (2005). ''The New Imperialism.'' New York: Oxford University Press USA, Ch. 3: "Accumulation by Dispossession," 137-182.
</ref>

[[Structural functionalism |Structural functionalists]] such as [[Talcott Parsons]] and neofunctionalists such as [[Niklas Luhmann]] have incorporated system theory to describe society and its components.

The [[sociology of religion]] finds both open and closed systems within the field of [[religion]].<ref>
{{cite book
 | editor1-last = Henderson
 | editor1-first = Ian H.
 | editor2-last = Oegema
 | editor2-first = Gerbern S.
 | editor3-last = Parks Ricker
 | editor3-first = Sara
 | title = The Changing Face of Judaism, Christianity, and Other Greco-Roman Religions in Antiquity
 | url = https://books.google.com/books?id=G5bXAAAAMAAJ
 | series = Volume 2 of Studien zu den Jüdischen Schriften aus hellenistisch-römischer Zeit
 | year = 2006
 | location = Gütersloh
 | publisher = Gütersloher Verlagshaus
 | publication-date = 2006
 | page = 21
 | isbn = 9783579053615
 | access-date = 11 June 2021
 | quote = The example of setting up new cults demonstrates how widely spread religious competence is in this open system [...].
}}
</ref><ref>
{{cite book
 | last1 = Rich
 | first1 = John Martin
 | title = Humanistic Foundations of Education
 | year = 1971
 | url = https://books.google.com/books?id=hP4DAAAAMAAJ
 | publisher = C. A. Jones Publishing Company
 | publication-date = 1971
 | page = 31
 | access-date = 11 June 2021
 | quote = No matter how definitive the evidence produced to the contrary, religionists deny that it in any way falsifies their knowledge-claims. Religion is not an open system.
}}
</ref>

==Thermodynamics==
{{see also|Thermodynamic system#Open system|Thermodynamics#System models}}

==Systems engineering==
{{see also|Systems engineering|Signal processing|Control theory|Black box}}

==See also==
* [[Business process]]
* [[Complex system]]
* [[Dynamical system]]
* [[Glossary of systems theory]]
* [[Ludwig von Bertalanffy]]
* [[Maximum power principle]] 
* [[Non-equilibrium thermodynamics]]
* [[Open system (computing)]]
* [[Open System Environment Reference Model]]
* [[Openness]]
* [[Phantom loop]]
* [[Thermodynamic system]]

==References==
<references/>

==Further reading==
* Khalil, E.L. (1995). Nonlinear thermodynamics and social science modeling: fad cycles, cultural development and identificational slips.  ''The American Journal of Economics and Sociology'', Vol. 54, Issue 4, pp.&nbsp;423–438.
* Weber, B.H. (1989).  Ethical Implications Of The Interface Of Natural And Artificial Systems. ''Delicate Balance: Technics, Culture and Consequences'':  Conference Proceedings for the Institute of Electrical and Electronics Engineers.

==External links==
* [http://pespmc1.vub.ac.be/Asc/OPEN_SYSTE.html OPEN SYSTEM], [[Principia Cybernetica]] Web, 2007.

[[Category:Cybernetics]]
[[Category:Thermodynamic systems]]