Source: 1970s, Ecodynamics: A New Theory Of Societal Evolution, 1978, p. 20
“A physical system is just that: a physical system. What is systematized is matter itself, and the processes in which the system is realized are also material. But a biological system is more complex: it is both biological and physical — it is matter with the added component of life; and a social system is more complex still: it is physical, and biological, with the added component of social order, or value. … A semiotic system is still one step further in complexity: it is physical, and biological, and social —and also semiotic: what is being systematized is meaning. In evolutionary terms, it is a system of the fourth order of complexity”
Michael Halliday (2005, p. 68) as cited in: Andrew Halliday and Marion Glaser (2011) "A Management Perspective on Social Ecological Systems". In: Human Ecology Review, Vol. 18, No. 1, 2011.
1970s and later
Help us to complete the source, original and additional information
Michael Halliday 23
Australian linguist 1925–2018Related quotes
Source: The Functions of the Executive (1938), p. 98-99, footnote
Source: Textual politics: Discourse and social dynamics, 1995, p. 159

Michael Halliday (2006, p. 68) as cited in: Andrew Halliday and Marion Glaser (2011).
1970s and later

Francis Heylighen, 1990, "Classical and non-classical representations in physics I." Cybernetics and Systems 21. p. 423; As cited by: Hieronymi, A. (2013), Understanding Systems Science: A Visual and Integrative Approach. Syst. Res.. doi: 10.1002/sres.2215
Von Bertalanffy (1950) " The Theory of Open Systems in Physics and Biology http://vhpark.hyperbody.nl/images/a/aa/Bertalanffy-The_Theory_of_Open_Systems_in_Physics_and_Biology.pdf" In: Science, January 13, 1950, Vol. 111. p. 23
1950s

“The observing mind is not a physical system, it cannot interact with any physical system.”
Nature and the Greeks (1954)
Context: The observing mind is not a physical system, it cannot interact with any physical system. And it might be better to reserve the term "subject" for the observing mind. … For the subject, if anything, is the thing that senses and thinks. Sensations and thoughts do not belong to the "world of energy."
As cited in: Debora Hammond (2005). "Philosophical and Ethical Foundations of Systems Thinking", in: tripleC 3(2): pp. 20–27.
1950s, Problems of Life (1952, 1960)

Systems Movement: Autobiographical Retrospectives (2004)
Source: Enterprise modeling within an enterprise engineering framework (1996), p. 993