Difference between revisions of "Origins of the Systems Approach"
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==Systems Methodologies== | ==Systems Methodologies== | ||
− | + | A methodology is a body of tools, procedures, and methods applied to a problem situation, ideally derived from a theoretical framework. These describe structured approaches to problem understanding and/or resolution making use of some of the concepts of Systems Thinking. These methodologies are generally associated with a particular System [[Paradigm (glossary)]] or way of thinking, which has a strong influence on the three aspects of a Systems Approach described above. A paradigm is distinct from a theory. A paradigm is a theoretical framework. Kuhn (1962) first popularized the term. | |
− | These paradigms arise from the different system movements discussed | + | These paradigms arise from the different system movements discussed in [[History of Systems Science]]. The most widely used groups of methodologies are as follows: |
#[[Hard System (glossary)]] methodologies, (Checkland 1978), set out to select an efficient means to achieve a predefined and agreed end. | #[[Hard System (glossary)]] methodologies, (Checkland 1978), set out to select an efficient means to achieve a predefined and agreed end. |
Revision as of 23:05, 12 August 2012
This article is part of the Systems Science Knowledge Area. It gives some of the history and detail of the development of a number of different Systems Approaches by the system science community. Some of these ideas form the basic theory and methods of Systems Thinking.
What is a Systems Approach?
In Bertalanffy's Introduction to his 1968 GST book, he says:
“Thus a “systems approach” became necessary. A certain objective is given; to find ways and means for its realisation requires the system specialist (or team of specialists) to consider alternative solutions and to choose those promising optimisation at maximum efficiency and minimum cost in a tremendously complex network of interactions”. (Bertalanffy, 1968, page 4)
He goes on to list, on pp. 19-24, as elements of a systems approach: “classical” systems theory (differential equations); computerization and simulation; compartment theory; set theory; graph theory; net theory; cybernetics; information theory; theory of automata; game theory; decision theory; queuing theory; and models in ordinary language. Bertalanffy's view of systems, focusing on systems as dynamic complexes that have both structure and process, is the innovative essence of the systems paradigm, and can arguably be taken as the "canonical view" from systems science.
In Systems Thinking the term Systems Approach is often used, e.g. (Churchman 1979), to describe the basic philosophy of holism and in particular of considering a System from the view point of those outside its boundary. There are many demonstrations that choosing too narrow a boundary, either in terms of scope or timeline, results in the problem of the moment being solved only at the expense of a similar or bigger problem being created somewhere else in space, community or time. This is the “shifting the burden” archetype described by (Senge, 2006) and Meadows (2010).
A systems approach views a “system” as a “holon” – an entity that is itself a “whole system” - as it interacts with a mosaic of other holons in its wider environment (Hybertson, 2009), and also as made up of interacting parts. We can use this model recursively – each part of the system may be a system in its own right, and can itself be viewed both as an entity as seen from outside, and as a set of interacting parts. This model also applies in upwards recursion, so the original “system of interest” is an interacting part of one or more wider systems.
This means that an important skill in a systems approach is to identify the “natural holons” in the problem situation and solution systems, and to make the partitioning of responsibilities match the “natural holons”, so as to minimise the coupling between parallel activity when applying a solution. This is the “cohesive/loose coupling” heuristic that has been around for a long time in many design disciplines.
Another consequence of the holistic nature of a systems approach is that it considers not only a problem situation and a solution system but also the system created and deployed to apply one to the other. A Systems Approach must consider the boundary of the system of concern, and the boundary of the system inquiry (or model). Real systems are always open, i.e., they interact with their environment or supersystem(s). Real models are always closed due to resource constraints. So there is an ongoing negotiation to relate the two in systems practice, and the judgement to do so is greatly helped by an appreciation of the difference between them.
Thus, a Systems Approach can be characterised by how it considers problems, solutions and the problem resolution process itself. Considering problems holistically, setting problem boundaries though understanding of natural system relationships and trying to avoid unwanted consequences. Creating solutions based on sound system principles, in particular creating system structures which reduce organised complexity and unwanted emergent properties. Using models in both problem understanding and solution creation, while understanding the limitiations of such models.
Systems Methodologies
A methodology is a body of tools, procedures, and methods applied to a problem situation, ideally derived from a theoretical framework. These describe structured approaches to problem understanding and/or resolution making use of some of the concepts of Systems Thinking. These methodologies are generally associated with a particular System paradigm or way of thinking, which has a strong influence on the three aspects of a Systems Approach described above. A paradigm is distinct from a theory. A paradigm is a theoretical framework. Kuhn (1962) first popularized the term.
These paradigms arise from the different system movements discussed in History of Systems Science. The most widely used groups of methodologies are as follows:
- hard system methodologies, (Checkland 1978), set out to select an efficient means to achieve a predefined and agreed end.
- soft system methodologies, (Checkland 1999), are interactive and participatory approaches to assist groups of diverse participants to alleviate a complex, problematic situation of common interest.
- critical systems thinking methodologies,(Jackson 1985), attempts to provide a framework in which appropriate hard and soft methods can be applied as appropriate to the situation under investigation.
Systems dynamics
Systems Dynamics (SD) uses some of the ideas of cybernetics to consider the behavior of systems as a whole in their environment. SD was developed by Jay Forrester in the 1960’s (Forrester 1961). He was interested in modeling the dynamic behavior of systems such as populations in cities, industrial supply chains.
System dynamics is an approach to understanding the behaviour of complex systems over time. It deals with internal feedback loops and time delays that affect the behaviour of the entire system. The main element of SD are:
- The understanding of the dynamic interactions in a problem or solution as a system of feedback loops. modelled using a Causal Loop Diagram
- Quantative modelling of system performance as an accumulation of Stocks (any entity or property which varies over time) and Flows (representations of the rate of change of a stock.
- The creation of dynamic simulations, exploring how the value of key parameters change over time. A wide range pof software tools are available to support this.
These elements help describe how even seemingly simple systems display baffling nonlinearity.
SD is also used by Senge (Senge 1990) in his influential book The Fifth Discipline. This book advocates a system thinking approach to organization, and makes extensive use of SD notions of feedback and control.
Hard Systems Methodologies
Checkland (Checkland 1975) classifies hard system methodologies, which set out to select an efficient means to achieve a predefined end, under the following headings:
- System Analysis, the systematic appraisal of the costs and other implications of meeting a defined requirement in various ways.
- Systems Engineering, the set of activities that together lead to the creation of a complex man-made entity and/or the procedures and information flows associated with its operation.
Operational Research is also considered a hard system approach, closely related to the Systems Analysis approach developed by the Rand Corporation, in which solutions are known but the best combinations of these solutions must be found. There is some debate as to whether System Dynamics is a hard approach, which is used to assess the objective behavior of real situations. Many application of SD have focused on the system, however it can and has also be used as part of a soft approach including the modelling of subjective perceptions (Lane 2000).
Systems Engineering allows for the creation of new solution systems, based upon available technologies. This hard view of systems engineering as a solution focused approach applied to large, complex and technology focused solutions, is exemplified by (Jenkins 1969; Hall 1962) and early defense and aerospace standards.
NOTE: Historically, the systems engineering discipline was primarily aimed at developing, modifying or supporting hard systems. More recent developments in systems engineering have incorporated problem focused thinking and agile solution approaches. It is this view of SE that is described in this SEBoK.
All of these hard approaches use systems thinking to ensure complete and viable solutions are created and/or as part of the solution optimization process. These approaches are appropriate to unitary problems, but not when the problem situation or solution technologies are unclear.
Soft Systems and Problem Structured Methods
Problem Structuring Methods (PSM) are interactive and participatory approaches to assist groups of diverse participants to alleviate a complex, problematic situation of common interest. Typically the hardest element of the situation is framing the issues which constitute the problem (Minger and Resenhead 2004).
PSM use systems and systems thinking as an abstract framework for investigation, rather than a structure for creating solutions. Systems descriptions are used to understand the current situation and describe an idealized future. Interventions directly in the current organization to move towards the idea recognize that the assumptions and mental models of the participants are an important obstruction to change and that these differing views cannot be dismissed but must form part of the intervention approach.
Peter Checkland’s action research program, see Systems Science, in the 1980‘s forms the basis of work by Checkland, Wilson and others in the development of soft systems methodology (SSM) (Checkland 1999; Wilson 2001). SSM formalizes the idea of a soft approach using systemic thinking to expose the issues in a problem situation and guide interventions to reduce them. SSM provides a framework of ideas and models to help guide participants through this systemic thinking.
Other PSM approaches include Interactive Planning Approach (Ackoff 1981); Social Systems Design (Churchman 1968), and Strategic Assumptions Surfacing and Testing (Mason and Mitroff 1981).
SSM and other soft approaches use systems thinking to ensure problem situations are fully explored and resolved. These approaches are appropriate to pluralist problems. Critics of SSM suggest that it does not consider the process of intervention, and in particular how differences in power between individuals and social groups impacts the effectiveness of interventions.
Critical systems thinking and Multimethodology
The development of a range of hard and soft methods naturally leads to the question of which method to apply when (Jackson 1989). critical systems thinking (CST) or Critical Management Science Jackson (Jackson 1985) attempts to deal with this question.
The word critical is used in two ways. Firstly, critical thinking considers the limits of knowledge and investigates the limits and assumptions of hard and soft systems, as discussed in the above sections. From this comes frameworks and meta-methodology for when to apply different methods such as Total Systems Intervention (TSI) (Flood and Jackson 1991).
The Multi-Methodology approach takes this aspect of critical thinking one stage further to recognize the value of combining techniques from several hard or soft methods as needed (Mingers and Gill 1997).
The second aspect of critical thinking considers the ethical, political and coercive dimension and the role of system thinking in society, see below.
Selecting Systems Methodologies
Jackson proposes a frame for considering which approach should be applied, please see: Jackson's Framework. In Jackson's framework the following definitions apply to the participants involved in solving the problem:
- unitary : A problem situation in which participants "have similar values, beliefs and interests. They share common purposes and are all involved, in one way or another, in decision-making about how to realize their agreed objectives." (Jackson 2003, p. 19)
- pluralist : A problem situation involving participants in which "although their basic interests are compatible, they do not share the same values and beliefs. Space needs to be made available within which debate, disagreement, even conflict, can take place. If this is done, and all feel they have been involved in decision-making, then accommodations and compromises can be found. Participants will come to agree, at least temporarily, on productive ways forward and will act accordingly." (Jackson 2003, p. 19)
- coercive : A problem situation in which the participants "have few interests in common and, if free to express them, would hold conficting values and beliefs. Compromise is not possible and so no agreed objectives direct action. Decisions are taken on the basis of who has most power and various forms of coercion employed to ensure adherence to commands." (Jackson 2003, p. 19)
Jackson's framework suggests that for simple and complex systems with unitary participants, hard and dynamic systems thinking applies, respectively. For simple and complex systems with pluralist participants, soft systems thinking applies. For simple and complex systems with coercive participants, emancipatory and postmodernist system thinking applies, respectively. These thinking approaches consider all attempts to look for system solutions to be temporary and ineffective in situations where the power of individuals and groups of people dominate any system structures we create. They advocate an approach which encourages diversity, free thinking and creativity of individuals and in the organization's structures. Thus, modern system thinking has the breadth needed to deal with a broad range of complex problems and solutions.
While these ideas sit at the extreme of system thinking as a tool for problem solving, Jackson (Jackson 2003) identifies the work of some authors who have included these ideas into their systems approach.
References
Works Cited
Bertalanffy, L. 1968. General Systems Theory. New York, Ny, USA: George Braziller, Inc.
Ackoff, R.L. 1981. Creating the Corporate Future. New York, NY, USA: Wiley and Sons.
Checkland, P. 1975. "The Origins and Nature of “Hard” Systems Thinking." Journal of Applied Systems Analysis, 5(2): 99-110.
Checkland, P. 1999. Systems Thinking, Systems Practice, New York, NY, USA: John Wiley & Sons.
Churchman, C.W. 1968. The Systems Approach. New York, NY, USA: Dell Publishing.
Churchman, C. West. 1979. "The Systems Approach and Its Enemies". New York: Basic Books.
Flood, R. and M. Jackson. 1991. Creative Problem Solving: Total Systems Intervention. London, UK: Wiley.
Forrester, J. 1961. Industrial Dynamics. Cambridge, MA, USA: MIT Press.
Hall, A.D. 1962. A Methodology for Systems Engineering. New York, NY, USA: Van Nostrand Reinhold.
Hybertson, D, 2009. Model-oriented Systems Engineering Science: A Unifying Framework for Traditional and Complex Systems (CRC Complex and Enterprise Systems Engineering)
Jackson, M. 1985. "Social Systems Theory and Practice: the Need for a Critical Approach." International Journal of General Systems. 10: 135-151.
Jackson, M. 1989. "Which Systems Methodology When? Initial Results from a Research Program." In: R Flood, M Jackson and P Keys (eds). Systems Prospects: the Next Ten Years of Systems Research. New York, NY, USA: Plenum.
Jackson, M. 2003. Systems Thinking: Creating Holisms for Managers. Chichester, UK: Wiley.
Jenkins, G.M. 1969. The Systems Approach. In Beishon, J. and G. Peters (eds.), Systems Behavior, 2nd ed. New York, NY, USA: Harper and Row.
Kuhn, T.S. The Structure of Scientific Revolutions. Chicago: University of Chicago Press, 1962
Lane, D. 2000 “Should System Dynamics be Described as a `Hard' or `Deterministic' Systems Approach?” Systems Research and Behavioral Science 17, 3–22 (2000) John Wiley & Sons, Ltd.
Mason, R.O. and I.I. Mitroff. 1981. Challenging Strategic Planning Assumptions: Theory, Case and Techniques. New York, NY, USA: Wiley and Sons.
Mingers, J. and A. Gill. 1997. Multimethodology: Theory and Practice of Combining Management Science Methodologies. Chichester, UK: Wiley.
Mingers, J. and J. Rosenhead. 2004. "Problem Structuring Methods in Action." European Journal of Operations Research. 152(3) (Feb. 2004): 530-554.
Senge, P. M. 1990, 2006. The Fifth Discipline: The Art and Practice of the Learning Organization. New York, Doubleday/Currency.
Wilson, B. 2001. Soft Systems Methodology—Conceptual Model Building and Its Contribution. New York, NY, USA: J.H.Wiley.
Primary References
Checkland, P. 1999. Systems Thinking, Systems Practice, New York, NY, USA: John Wiley & Sons.
Forrester, J. 1961. Industrial Dynamics. Cambridge, MA, USA: MIT Press.
Jackson, M. 1985. Social Systems Theory and Practice: the Need for a Critical Approach. International Journal of General Systems 10: 135-151.
Additional References
Jackson, M.C. and Keys, P. 1984. "Towards a System of Systems Methodologies." The Journal of the Operational Research Society. 35(6) (Jun. 1984): 473-486.
Sterman, John D. (2001). "System dynamics modeling: Tools for learning in a complex world". California management review 43 (4): 8–25.
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