Systems thinking

thumb|upright=1.2|right|Depiction of systems thinking about society

Systems thinking is a way of making sense of the complexity of the world by looking at it in terms of wholes and relationships rather than by splitting it down into its parts. It has been used as a way of exploring and developing effective action in complex contexts, enabling systems change. Systems thinking draws on and contributes to conceptual systems, systems theory, and the system sciences.

History

Ptolemaic system versus the Copernican system

The term system has multiple related meanings: Robert Hooke (1674) used it in multiple senses, in his System of the World, which are cataloged in Hipparchus' and Ptolemy's Star catalog. Hooke's claim was answered in magisterial detail by Newton's (1687) Philosophiæ Naturalis Principia Mathematica, Book three, The System of the World (that is, the system of the world is a physical system).

Newton's approach, using dynamical systems continues to this day. In brief, Newton's equations (a system of equations) have methods for their solution.

Feedback control systems

thumb|left|upright=1.5|System output can be controlled with [[feedback.]]

By 1824, the Carnot cycle presented an engineering challenge, which was how to maintain the operating temperatures of the hot and cold working fluids of the physical plant. In 1868, James Clerk Maxwell presented a framework for, and a limited solution to, the problem of controlling the rotational speed of a physical plant. Maxwell's solution echoed James Watt's (1784) centrifugal moderator (denoted as element Q) for maintaining (but not enforcing) the constant speed of a physical plant (that is, Q represents a moderator, but not a governor, by Maxwell's definition).

Maxwell's approach, which linearized the equations of motion of the system, produced a tractable method of solution. Methods for solutions of the systems of equations then become the subject of study, as in feedback control systems, in stability theory, in constraint satisfaction problems, the unification algorithm, type inference, and so forth.

Systems thinking, born from the visionary contributions of theoretical biologist Ludwig von Bertalanffy, computer scientist Jay Forrester, and their contemporaries, reached its zenith in the 1990s with the release of Peter Senge’s seminal work, The Fifth Discipline, a landmark in intellectual exploration.

Applications

:"So, how do we change the structure of systems to produce more of what we want and less of that which is undesirable? ... MIT’s Jay Forrester likes to say that the average manager can ... guess with great accuracy where to look for leverage points—places in the system where a small change could lead to a large shift in behavior".— Donella Meadows, (2008) Thinking In Systems: A Primer p.145

Characteristics

thumb|upright=0.8|System boundary in context

thumb|upright=0.8|System input and output allows exchange of energy and information across boundary.

"a system is a collection of things that are interconnected and interdependent from which stuff emerges"

-Walls & Flach (2025)

Particular systems

Political systems were recognized as early as the millennia before the common era.
Biological systems were recognized in Aristotle's lagoon ca. 350 BCE.
Economic systems were recognized by 1776.
Social systems were recognized by the 19th and 20th centuries of the common era.
Radar systems were developed in World War II in subsystem fashion; they were made up of transmitter, receiver, power supply, and signal processing subsystems, to defend against airborne attacks.
Dynamical systems of ordinary differential equations were shown to exhibit stable behavior given a suitable Lyapunov control function by Aleksandr Lyapunov in 1892.
Thermodynamic systems were treated as early as the eighteenth century, in which it was discovered that heat could be created without limit, but that for closed systems, laws of thermodynamics could be formulated. Ilya Prigogine (1980) has identified situations in which systems far from equilibrium can exhibit stable behavior; once a Lyapunov function has been identified, future and past can be distinguished, and scientific activity can begin.

Resilient systems are self-organizing;

The scope of functional controls is hierarchical, in a resilient system. in particular, there can be twelve boundary categories for the systems when organizing one's thinking and actions.

Critical systems thinking, including the E P I C approach.
DSRP, a framework for systems thinking that attempts to generalise all other approaches.
Ontology engineering of representation, formal naming and definition of categories, and the properties and the relations between concepts, data, and entities.
Soft systems methodology, including the CATWOE approach and rich pictures.
Systemic design, for example using the double diamond approach.
System dynamics of stocks, flows, and internal feedback loops.
Viable system model: uses 5 subsystems.

Notes

References

Sources

Adam Walls & John Flach (2024) "Do systems exist? A conversation: A short discussion on founding concepts behind general systems theory and soft systems.
Russell L. Ackoff (1968) "General Systems Theory and Systems Research Contrasting Conceptions of Systems Science." in: Views on a General Systems Theory: Proceedings from the Second System Symposium, Mihajlo D. Mesarovic (ed.).
A.C. Ehresmann, J.-P. Vanbremeersch (1987) Hierarchical evolutive systems: A mathematical model for complex systems" Bulletin of Mathematical Biology Volume 49, Issue 1, Pages 13–50
NJTA Kramer & J de Smit (1977) Systems thinking: Concepts and Notions, Springer. 148 pages
A. H. Louie (November 1983) "Categorical system theory" Bulletin of Mathematical Biology volume 45, pages 1047–1072
DonellaMeadows.org Systems Thinking Resources
Gerald Midgley (ed.) (2002) Systems Thinking, SAGE Publications. 4 volume set: 1,492 pages List of chapter titles

Robert Rosen. (1958) “The Representation of Biological Systems from the Standpoint of the Theory of Categories". Bull. math. Biophys. 20, 317–342.
Peter Senge, (1990) The Fifth Discipline