Systems thinking

Systems thinking is a mental model that promotes the belief that the component parts of a system will act differently when isolated from its environment or other parts of the system, and argues against Descartes's reductionist view. It includes viewing systems in a holistic manner, rather than through purely reductionist techniques. It promotes gaining insights into the whole by understanding the linkages and interactions between the elements that comprise the whole "system", consistent with systems philosophy. Systems Thinking recognizes that all human activity systems are open systems; therefore, they are affected by the environment in which they exist. Systems Thinking recognizes that in complex systems events are separated by distance and time; therefore, small catalytic events can cause large changes in the system. Systems thinking acknowledges that a change in one area of a system can adversely affect another area of the system; thus, it promotes organizational communication at all levels in order to avoid the silo effect.

Systems thinkers consider that:
 * a "system" is a dynamic and complex whole, interacting as a structured functional unit
 * information flows between the different elements that compose the system
 * a system is a community situated within an environment
 * information flows from and to the surrounding environment via semi-permeable membranes or boundaries
 * systems are often composed of entities seeking equilibrium, but can exhibit oscillating, chaotic, or exponential growth/decay behavior
 * For further details see complex system

Why use systems thinking techniques?
Systems thinkers are particularly interested in studying systems because changing a system frequently leads to counterintuitive system responses. For example feedback loops may operate to either keep the organization in check or unbalance it.

Traditional decision making tends to involve linear cause and effect relationships. By taking a systems approach, we can see the whole complex of bidirectional interrelationships. Instead of analysing a problem in terms of an input and an output, for example, we look at the whole system of inputs, processes, outputs, feedback, and controls. This larger picture will typically provide more useful results than traditional methods.

System thinking also helps us integrate the temporal dimension of any decision. Instead of looking at discrete "snapshots" at points in time, a systems methodology will allow us to see change as a continuous process.

Systems Thinking is a worldview based on the perspective of the systems sciences, which seeks to understand interconnectedness, complexity and wholeness of components of systems in specific relationship to each other. Systems thinking is not only constructivist, rather systems thinking embraces the values of reductionist science by understanding the parts, and the constructivist perspectives which seek to understand wholes, and more so, the understanding of the complex relationships that enable 'parts' to become 'wholes' as noted in the example below.

What is a system?
A system is any set (group) of interdependent or temporally interacting parts. Parts are generally systems themselves and are composed of other parts, just as systems are generally parts or components of other systems.

Systems thinking techniques may be used to study any kind of system -- natural, scientific, human, or conceptual.

Examples
Systems thinking often involves considering a "system" in different ways:
 * Rather than trying to improve the braking system on a car by looking in great detail at the composition of the brake pads (reductionist), the boundary of the braking system may be extended to include not only the components of the car, but the driver, the road and the weather, and considering the interactions between them.


 * Looking at something as a series of conceptual systems according to multiple viewpoints. A supermarket could be considered as a "profit making system" from the perspective of management, an "employment system" from the perspective of the staff, and a "shopping system" -- or perhaps an "entertainment system" -- from the perspective of the customers.  As a result of such thinking, new insights may be gained into how the supermarket works, why it has problems, or how changes made to one such system may impact on the others.

Methodologies
Systems thinking uses a variety of techniques that may be divided into:
 * Hard systems - involving simulations, often using computers and the techniques of operations research. Useful for problems that can justifiably be quantified.  However it cannot easily take into account unquantifiable variables (opinions, culture, politics, etc), and may treat people as being passive, rather than having complex motivations.
 * Soft systems - Used to tackle systems that cannot easily be quantified, especially those involving people interacting with each other or with "systems". Useful for understanding motivations, viewpoints, and interactions but, naturally, it doesn't give quantified answers.  Soft systems is a field that the academic Peter Checkland has done much to develop. Morphological analysis is a complementary method for structuring and analysing non-quantifiable problem complexes.
 * Evolutionary systems - the development of Evolutionary Systems Design by Bela H. Banathy integrates critical systems inquiry and soft systems methodologies to create a meta-methodology applicable to the design of complex social systems. These systems, similar to dynamic systems are understood as open, complex systems, but further accounts for their potential capacity to evolve over time. Banathy uniquely integrated the multidisciplinary perspectives of systems research (including chaos, complexity, cybernetics), cultural anthropology, evolutionary theory, and others.

Applications
Systems thinking is increasingly being used to tackle a wide variety of subjects in fields such as management, computing, engineering and the environment.