Tag Archives: epistemology

Not getting lost in process

Not getting lost in process

Debates about political process and endless delays in making decisions threaten to weaken trust in our democratic institutions especially with regard to pressing matters like the provision of adult social care. Politics has become a “prisoner of process” (Bagehot, 2025). 

Bagehot makes a good point and cites Blair in support of the observation that process, rather than being the means to the end, has become an end in itself. Bagehot draws on Stafford Beer’s (not attributed) POSIWID heuristic – the purpose of a system is what it does – to suggest that the system’s purpose has become an endless cycle of debate without action, although, in passing, observing that deliberation is necessary to “ensure that decisions are simply not made” (my emphasis). This is all good, but I think there are a number of conceptual errors that unhelpfully muddy the argument.

Starting with Beer’s POSIWID, it is a simple observation that system is being interpreted here in a narrow sense. We would hope that any system of governance has feedback mechanisms in it. Rather than a simple linear sequence of steps we would expect something like deliberation → action → observation (of effects of actions) → comparison → deliberation → …, where the comparison step derives an error signal based on the difference between what was intended and what happened. This system should operate in a continual cycle of feedback – it is both unlikely that our actions achieve the desired effect and the world keeps changing anyway. While we might conclude that the evident purpose of the system is to endlessly deliberate i.e., deliberation → deliberation → …, we could go a bit further and observe where the system is broken – the action element is missing and therefore the feedback loop is not operating. I think we would both agree that the system needs to be repaired. 

POSIWID is useful and the elicitation of feedback loops, at any desirable level of detail, provides a powerful analytical tool; but I believe there is another way of looking at this problem and the use of a process approach offers some benefits, rather than being consigned in the narrow sense to a trap of deliberation. The key can be found in the way in which we use language in our analyses. I have previously railed against the use of language like ‘solution’ and ‘fix’ in the context of complex problems, but in the analysis of the feedback loop above I rather consciously used ‘deliberation’, ‘action’ and ‘observation’ to emphasise the linearisation of what should be a system and that this arises from the nominalization of elements that should be thought of as verbs.

Getting stuck in a process of deliberation, or an endless sequence of deliberations, is likely when all the actors, including analysts and commentators (expert and otherwise), are constrained by their nominalizations. A better conceptualising of process thinking is to think of governing as a process and that for it to perform it must consist of further processes such as deliberating, acting (or effecting change, or intervening) and observing (or measuring). These processes are all necessary for governing but none are sufficient, by themselves, for properly enacting the process of governing. Note the use of the gerund form of the verb to convey a sense of continual ongoingness of the process. We can decompose this schema (or model) to any level of detail that is required using conditions of necessity and sufficiency as a test on whether a process is required in the model. 

Coming back to Bagehot’s analysis, we can clearly agree that the process of acting is not working well, but it cannot be reduced to a simple intervention that is yet to happen and that will somehow ‘fix’ the problem. The process of deliberating is obviously not working well either, it is clearly not sufficient by itself to enable the process of governing and our measure of its performance should of necessity include its commissioning of useful planning to enable acting. Rather than being prisoners of process, we would be better served by realising that processes are all there are, both in the world and in our ways of intervening in the world. To do this, amongst other things, requires a change in our language, away from nominalizations, especially ones like ‘action’ and ‘solution’, and recognise that acting or intervening is a continuing and ongoing process and may be enacted at any level of scale (socially, temporally, spatially,…).

In the case of adult social care there is clearly a whole lot of process detail that is completely missing between deliberating and intervening and nobody seems to be talking about it. We are left with unedifying analyses and useless solutionist traps. 

There are no solutions to complex problems

There are no solutions to complex problems

This may sound like a rather bleak pronouncement and completely contrary to the way in which complex problems are presented and discussed by, amongst others, politicians, the media, and commentators – expert and otherwise. However, I believe we have a language problem that gets in the way of having informed discussions about complex problems and how we work to do something about them. I want to explain that whenever we hear a statement that articulates a claim to have a solution or fix to a complex problem the speaker is making a category mistake, in effect their claim is logically meaningless. To then discuss and debate such statements, especially by introducing quantitative measures of success such as targets, we compound the category mistake and waste effort – both time and resources – chasing after illusions. 

To support my argument, let’s start with considering the idea of problems that do have a solution. The simplest category is puzzles, and good examples range from crosswords and sudoku through to spatial puzzles like jigsaws and Rubik cubes. There is one solution that everyone can agree is correct, and while it is possible to not always find the solution (i.e., not complete the puzzle), or to only solve part of the puzzle, it is not possible to have an ambiguous solution. The answer is either right, wrong, or perhaps only partially right. Many maths problems fall into this ‘puzzle’ category too. Skills can be developed at solving such problems. We can set tests and examine the performance of the problem solver by not just checking for the right answer but also for them to ‘show working’. 

If we next look at the solution to a puzzle we can see that once we have produced it the problem ceases to exist. By ceases to exist I mean that the problem has a known solution and does not need to be found again. Of course, the solution can be kept secret or not communicated – that is, after all, the enduring property of puzzles as tests or enjoyment. The dictionary definition of solution just reaffirms this straightforward notion as a resolution or answer. In process terms, a process for solving or fixing a problem is a process that is designed to make the problem go away. The problem is solved or fixed and there is nothing else that needs to be done.

From this starting point of problems as puzzles with singular solutions it is not too difficult to extend the argument to problems that have multiple solutions but still nonetheless have the property that whichever solution is chosen to fix the problem, the problem remains fixed (or solved) and ceases to exist. Good examples here are algorithms or computer programs designed to address a specific problem. We could also re-cast the notion of a requirement or a constraint as a problem to be solved and accept that there will be multiple possible solutions that adequately satisfy the requirement/constraint. We might introduce some notion of efficiency – in use of resources and/or time – associated with each solution and therefore have some objective measure to choose between solutions. For example, there are many different algorithms for sorting a data set but for the same available computing resource, some algorithms would take less time to sort the data than others. We can think of this category of problems as well-defined.

By increasing the complexity of the problem, we start to run into difficulties in deciding whether we have a solution. We may be able to formulate the problem quite well in that we can write down a set of requirements and constraints, but solutions might be contested. For example, we may need to improve travel links between communities on either side of a river. There are many different ways of facilitating this ranging from a footbridge, road bridge, ferry, tunnel, rail bridge and so on. Problem formulation requires delving into what improve means and for whom, and deciding which solution to choose is a function of many considerations, not least budgets, timescales, impact on environment etc. After considering all these factors and embarking on a construction project following a well-defined problem formulation (as a specification or a project plan), we may still be in some doubt whether we have achieved a solution to the original problem.

The final class of problems defy both formulation and solution and have been variously labelled as wicked (following Rittel and Webber (1973, pp. 161-167)), or messy (following Ackoff, 1974, pp. 20-21)) or swampy (following Schön (1987, p. 3)). Using the definition of Rittel and Webber, so called wicked problems can be defined as follows (Yearworth, 2025, pp. 18-19):

  1. There is no definitive formulation – formulating a wicked problem is the problem. It is not possible to approach a wicked problem with preconceived notions of how it might be addressed, the only way forward is to start a process of enquiry and develop ways forward from there. 
  2. There are no stopping rules. The process of intervening is also the same as understanding the nature of the problem – the intervention is ‘good enough’ or the best that can be achieved within other limitations external to the process (e.g. time, budget, patience, etc.).
  3. Interventions are not right or wrong, there are no formal decision rules for defining correctness, they can only be viewed as making things better or worse for certain interests. Judgments will depend on personal interests and values. 
  4. There is no immediate or ultimate test for an intervention. Interventions will generate ‘waves of consequences over an extended – virtually an unbounded – period of time’. The consequences of an intervention are thus difficult to evaluate because the consequences will be continually changing. 
  5. Interventions are ‘one-shot operations’, and experiments are difficult to conduct. Every intervention is consequential and effectively irreversible. Interventions are essentially unique in nature – we cannot intervene in the same problem context twice as our interventions change the problem context. 
  6. There is no enumerable, exhaustively describable set of possible interventions. There are no criteria that enable us to judge whether we have found all of the interventions that are possible in a given problem context. It is a matter of realistic judgment about how expansive the process of enquiry should be.
  7. Every wicked problem is essentially unique. ‘Essentially’ implies that aspects may be common, but to think in terms of categories or classes of wicked problems with common ‘solutions’ is misleading. 
  8. Wicked problems can be considered symptoms of other problems, i.e., there is inherent systemicity in the world. ‘The level at which a problem is settled depends upon the self-confidence of the analyst and cannot be decided on logical grounds. There is nothing like a natural level of a wicked problem. Of course, the higher the level of a problem’s formulation, the broader and more general it becomes: and the more difficult it becomes to do something about it.’ 
  9. Can be contested at the level of explanation; there is likely to be conflicting evidence or data. It is not possible to rigorously test hypotheses about interventions due to their unique circumstances.
  10. Whereas scientific progress arises as a consequence of refuted hypotheses (in a sense, being wrong is good), in the area of policy and planning, decisions that have negative consequences are not tolerated (being wrong is not good).

In order to avoid the possibility of confusing the notion of solution with this type of complex problem I have introduced the use of intervention into this definition – the act of intervening in this type of problem context – and it is within this definition that the source of the category mistake can be found. We may intervene in these problem contexts but to say that we will solve or fix the problem is to logically contradict the definition. It would be perfectly reasonable to contest the definitions, but given the messiness of problem contexts that demand our attention I believe it is reasonable to assert that a category (or categories) of problem exist that are not puzzles or well defined/formulated (Also see Pidd (2009, p.44)). Our first action must be to structure the problem.

This category of problem is endemic and we must take heed of these properties. To blithely talk of solutions and fixes in the context of these types of complex problems is misleading. If this arises from a genuine misunderstanding about the nature of wicked/messy problems then perhaps it is understandable. However, journalists, politicians and expert commentators should be aware of these characteristics and to continue with using the language of solutions and fixes is to exhibit partiality or deliberate deceit. 

I write about this extensively in Section I of my book (Yearworth, 2025, pp. 1-43).

Ackoff, R. L. (1974). Redesigning the future: a systems approach to societal problems. Wiley-Interscience: New York; London

Pidd, M. (2009). Tools for thinking: modelling in management science (3rd ed.). John Wiley & Sons: Chichester.

Rittel, H., & Webber, M. (1973). Dilemmas in a general theory of planning. Policy Sciences, 4(2), 155–169. https://doi.org/10.1007/BF01405730

Schön, D. A. (1987). Educating the reflective practitioner. Jossey-Bass: San Francisco, CA

Yearworth, M. (2025). Problem Structuring: Methodology in Practice (1st ed.). John Wiley & Sons, Inc.: Hoboken. https://doi.org/10.1002/9781119744856 

Modelling HPM as a PSM, using HPM

Modelling HPM as a PSM, using HPM

I conclude my book on Problem Structuring with some comments on a processual turn in Operational Research (Yearworth, 2025) and specifically comment

“In modelling the world processually we can also model our interventions within the same model … Or put more simply, problematic situations are processes as are the means of intervention.” (p. 270). 

Modelling our interventions specifically requires the possibility of representing our use of a problem structuring method as a model. Checkland and Poulter described the process of using Soft Systems Methodology (SSM) in the activity system ‘language’ of SSM itself (Checkland & Poulter, 2006, p. 194; Yearworth, 2025, p. 78). Checkland and Scholes went further and modelled the system to use SSM in the same purposeful activity system language i.e., the ongoing reflective practice of using SSM in client engagements (Checkland & Scholes, 1990, p. 294).  

The same approach has been used for describing the use of Hierarchical Process Models (HPM) for problem structuring. This was first manifest in the STEEP Project as means of self-evaluation of how well the methodology was performing, making use of the Italian Flag as a means of capturing judgement of process performance (Yearworth et al., 2015, p. 9). In the Healthy Resilient Cities project (Yearworth, 2015), we started to model the process of using the PSM within the model of the problematic situation itself (Yearworth, 2025, p. 173) i.e., the process <Improving the resilience of healthcare provisioning in Bristol…> contained within it the process <Using problem structuring>. Further work on exploiting the Italian Flag for capturing judgements of process performance in the use of a PSM was explored in depth by Lowe, Espinosa and Yearworth (2020).

The development of HPM as a PSM is described fully in Chapters 9 and 10 of my book. However, the work of modelling HPM as a PSM using HPM itself that was started in the STEEP project is still ongoing. The following shows its current incarnation in Strategyfinder.

HPM of using HPM as a PSM

Note that methodological learning, an essential element of using a PSM, is reflected in the model at Process #26 <Evaluating the engagement and improving our understanding …> and the processes it contains. The model also references other models that could be incorporated as enhancements, for example using the framework for improving facilitation developed by Ackermann (1996, p. 95), which has been interpreted in my book as another process model (Yearworth, 2025, p. 108). This illustrates the property that all HPM are composable according to their necessity and sufficiency for the success of the process that acts as the anchor for incorporation.

Ackermann, F. (1996). Participants’ perceptions on the role of facilitators using group decision support systems. Group Decision and Negotiation, 5(1), 93-112. https://doi.org/10.1007/BF02404178

Checkland, P., & Poulter, J. (2006). Learning for action : a short definitive account of soft systems methodology, and its use for practitioner, teachers and students. John Wiley & Sons: Chichester. 

Checkland, P., & Scholes, J. (1990). Soft systems methodology in action. John Wiley & Sons: Chichester. 

Lowe, D., Espinosa, A., & Yearworth, M. (2020). Constitutive rules for guiding the use of the viable system model: Reflections on practice. European Journal of Operational Research, 287(3), 1014-1035. https://doi.org/10.1016/j.ejor.2020.05.030

Yearworth, M. (2015). Healthy Resilient Cities: Building a Business Case for Adaption (NERC NE/N007638/1)[Grant]. Bristol. http://gotw.nerc.ac.uk/list_full.asp?pcode=NE%2FN007638%2F1

Yearworth, M. (2025). Problem Structuring: Methodology in Practice (1st ed.). John Wiley & Sons, Inc.: Hoboken. https://doi.org/10.1002/9781119744856

Yearworth, M., Schien, D., Burger, K., Shabajee, P., & Freeman, R. (2015). STEEP Project Deliverable D2.1(R2) – Energy Master Plan Process Modelling. STEEP PROJECT (314277) – Systems Thinking for Comprehensive City Efficient Energy Planning, pp78. Retrieved 26th January 2023, from https://www.grounded.systems/wp-content/uploads/2023/01/01_STEEP_D2.1_Energy_Master_Plan_process_model_update_M24_DEF_sent.pdf

Problem Structuring : Methodology in Practice

Problem Structuring : Methodology in Practice

My new book is now available!

Current perspectives on approaches to problem structuring in operational research and engineering and prospects for problem structuring methods applicable to a wide range of practice.

Despite the myriad successes of Operational Research (OR) in government and industry, critique of its continued relevance to complex, wicked problems led to the emergence and evolution of Soft OR as a more humanist orientation of the discipline centred on a methodological framing of techniques known as Problem Structuring Methods (PSMs). These have enabled OR practitioners to broaden the scope of OR to address complex problem contexts that require transforming, planning and strategising interventions for their clients. The original core PSMs of Soft Systems Methodology (SSM), Strategic Options Development and Analysis (SODA) and the Strategic Choice Approach (SCA) are presented using a new analytical framework based on constitutive rules, epistemologies, and affordances of the modelling approach. Practical considerations in PSM based interventions are discussed emphasising trust-building, stakeholder identification, facilitation and ethical practice. A wide range of PSM applications are surveyed demonstrating clear intersections with communities of practice grounded in the applied social sciences. The development of a new PSM based on Hierarchical Process Modelling (HPM) of purpose arising from a processual turn in engineering practice offers additional insights for the practice of Soft OR. New developments in PSM practice built on use of Group Support Systems (GSS) and exploiting developments in machine learning are presented. Prospects for bringing the Soft OR project back into better alignment with mainstream OR are discussed in the context of new education programs and a possible processual turn in OR.

Problem Structuring: Methodology in Practice contains four linked sections that cover:

  1. Problem formulation when dealing with wicked problems, justification for a methodological approach, the emergence of soft OR, the relevance of pragmatic philosophy to OR practice.  
  2. Traces debates and issues in OR leading to the emergence of soft OR, comparative analysis of PSMs leading to a generic framework for soft OR practice, addressing practical considerations in delivering PSM interventions.
  3. Charts the emergence of a problem structuring sensibility in engineering practice, introduces a new PSM based on hierarchical process modelling (HPM) supported by teaching and case studies, makes the case for a processual turn in engineering practice supported by HPM with relevance to OR practice.
  4. Evaluation of PSM interventions, survey of applications, use of group support systems, new developments supported by machine learning, re-contextualising soft OR practice.

Problem Structuring: Methodology in Practice is a thought-provoking and highly valuable resource relevant to all “students of problems.” It is suitable for any UK Level 7 (or equivalent) programme in OR, engineering, or applied social science where a reflective, methodological approach to dealing with wicked problems is an essential requirement for practice.

Note that some institutions may have access via their usual eBook provider (e.g. ProQuest, Perlego), if not by default on the subscription then by a separate order for this specific title.

A PSM Reading List


A PSM Reading List

  • Ackermann, F., & Eden, C. (2011). Making strategy: mapping out strategic success (2nd ed.). Sage: London.
  • Baert, P. (2005). Philosophy of the social sciences : towards pragmatism. Polity: Cambridge.
  • Callon, M., Lascoumes, P., & Barthe, Y. (2009). Acting in an uncertain world : an essay on technicaldemocracy. MIT: Cambridge, Mass.
  • Checkland, P. (1999). Systems thinking, systems practice: Includes a 30-year retrospective. John Wiley & Sons: Chichester.
  • Checkland, P., & Poulter, J. (2006). Learning for action : a short definitive account of soft systems methodology,and its use for practitioner, teachers and students. John Wiley & Sons: Chichester.
  • Checkland, P., & Scholes, J. (1999). Soft Systems Methodology in Action: Including a 30-year retrospective. John Wiley & Sons: Chichester.
  • Conklin, J. (2006). Dialogue mapping : building shared understanding of wicked problems. John Wiley & Sons: Chichester.
  • Eden, C., Jones, S., & Sims, D. (1983). Messing about in problems : an informal structured approach to their identification and management. Pergamon: Oxford.
  • Friend, J., & Hickling, A. (2005). Planning under pressure : the strategic choice approach (3rd ed.). Elsevier Butterworth-Heinemann: Oxford.
  • Keys, P. (Ed.). (1995). Understanding the process of operational research : collected readings. John Wiley & Sons: Chichester.
  • Kilgour, D. M., & Eden, C. (Eds.). (2020). Handbook of Group Decision and Negotiation. Springer International Publishing: Cham. doi:10.1007/978-3-030-12051-1
  • Morecroft, J. (2007). Strategic modelling and business dynamics : a feedback systems approach. John Wiley & Sons: Chichester.
  • Pidd, M. (Ed.). (2004). Systems modelling : theory and practice. John Wiley & Sons: Chichester.
  • Pidd, M. (2009). Tools for thinking : modelling in management science (3rd ed.). John Wiley & Sons: Chichester.
  • Rosenhead, J. (Ed.). (1989). Rational analysis for a problematic world : problem structuring methods for complexity, uncertainty and conflict. John Wiley & Sons: Chichester.
  • Rosenhead, J., & Mingers, J. (Eds.). (2001). Rational analysis for a problematic world revisited : problem structuring methods for complexity, uncertainty and conflict (2nd ed.). John Wiley & Sons: Chichester.
  • Salhi, S., & Boylan, J. (Eds.). (2022). The Palgrave Handbook of Operations Research. Palgrave Macmillan Cham. doi:10.1007/978-3-030-96935-6.
  • Senge, P. M. (1990). The Fifth Discipline: The Art and Practice of the Learning Organization. Random House: London.
  • Vennix, J. (1996). Group Model Building: Facilitating Team Learning Using System Dynamics. John Wiley & Sons: Chichester.
  • Yearworth, M. (2024). Problem Structuring : Methodology in Practice. John Wiley & Sons: Chichester.

Wicked problems and category mistakes

Wicked problems and category mistakes

This is a brief introduction to the notion of a wicked problem. It is based on the highly-cited paper by Rittel and Webber (1973). The following characterise wicked problems:

  1. There is no definitive formulation. In a sense, formulating a wicked problem is the problem
  2. There are no stopping rules. The process of intervening is also the same as understanding the nature of the problem – the intervention is “good enough” or the best that can be achieved within other limitations (e.g. of time, budget…)
  3. Interventions are not right or wrong, they can only be viewed as making things better or worse for certain interests i.e. the intervention has made things both better and worse depending on who you ask
  4. There is no immediate or ultimate test of an intervention. Interventions will generate “waves of consequences” over a period of time
  5. Interventions are “one-shot operations”, experiments are difficult to conduct, every intervention counts significantly, they are essentially unique in nature
  6. No enumerable, exhaustively describable, set of possible interventions
  7. Every wicked problem is essentially unique. “Essentially” implies that aspects may be common, but to think in terms of categories or “classes” of wicked problems with common “solutions” is misleading
  8. Wicked problems can be considered as symptoms of other problems i.e. there is inherent systemicity in the world
  9. Can be contested at the level of explanation, there is likely to be conflicting evidence or data

The corollary of this definition is that certain statements about problems are likely to be rendered false or meaningless if it can be shown that the problem is actually wicked, in effect the statement is demonstrating that a category mistake is being made. The following is not an exhaustive list:

  1. ‘Solving’ or ‘curing’ a wicked problem is a contradiction; there are no ‘solutions’, ‘cures’…
  2. Words that suggest an objective point of view used in the context of the problem at the very least need to be debated e.g. words like optimal, best, right, smart, correct, … all suggest the question – for whom? Alternatively, no decision taken should ever be considered wrong.
  3. Any statement of measurable quantity that supports an argument for the problem getting better or worse without acknowledging the dynamic complexity that systemicity implies i.e. “…worse then better…” is a more believable statement given dynamic complexity
  4. Statements that appear to deny the systemic nature of the problem e.g. ignoring requisite variety
  5. Containing irrefutable assertions of fact e.g. “…this proves conclusively that…”
  6. Use of binary choices, any mention of “silver bullets”
  7. Misrepresenting or ignoring plurality e.g. “The public…”
  8. Emphasis on producing plans rather planning as a process

If any of these corollaries are contested e.g. if someone claims to have a solution to a wicked problem, then they are likely to be making a claim about only an aspect of the problem, or only from a certain viewpoint; or their formulation is not that of a wicked problem i.e. they are talking about something ‘tame’. Statements that contain phrases like “…optimal solution…” or “…this proves conclusively that if we do this we will have the best outcome…” in the context of a wicked problem definitely signal a likely category mistake.

Category mistakes are a warning sign – be sceptical of claims being made. They suggest either misunderstanding or partiality.

It’s worth reading the Rittel and Webber paper. Despite its age, it still does an exceptionally good job of reminding us of the characteristics of wicked problems that’s just as relevant today.

The first steps towards a coherent approach to problem formulation can be found in Rosenhead’s (1996) introduction to Problem Structuring Methods.

Rittel, H. W. J., & Webber, M. M. (1973). Dilemmas in a general theory of planning. Policy Sciences, 4(2), 155-169. doi:10.1007/BF01405730
Rosenhead, J. (1996). What’s the problem? An introduction to problem structuring methods. Interfaces, 26(6), 117-131. doi:10.1287/inte.26.6.117

A Systems Reading List

A Systems Reading List

I often get asked to recommend books on systems thinking, systemic problem structuring, and systems modelling – from general introductions to specialist texts. In this update I have reduced the list to a more manageable length and split it into two parts – essential and further reading. Note that I recommend the 1999 versions of ‘Systems thinking, systems practice‘ and ‘Soft Systems Methodology in Action’ since they both include Checkland’s excellent reflections on 30-years’ of Soft Systems Methodology (SSM). If you are learning about and using SSM then I think you also need to know something about Strategic Options Development and Analysis (SODA)/JourneyMaking and the Strategic Choice Approach (SCA).

Essential Reading

  • Ackermann, F., & Eden, C. (2011). Making strategy : mapping out strategic success (2nd ed) London: Sage.
  • Beer, S. (1985). Diagnosing the system. Chichester: John Wiley & Sons Ltd.
  • Checkland, P. (1999). Systems thinking, systems practice: Including a 30-year retrospective. Chichester: John Wiley & Sons Ltd.
  • Checkland, P., & Poulter, J. (2006). Learning for action : a short definitive account of soft systems methodology, and its use for practitioner, teachers and students. Chichester: John Wiley & Sons Ltd.
  • Checkland, P., & Scholes, J. (1999). Soft Systems Methodology in Action: Including a 30-year retrospective. Chichester: John Wiley & Sons Ltd.
  • Jackson, M.C. (2019). Critical Systems Thinking and the Management of Complexity. Chichester: Wiley-Blackwell.
  • Midgley, G. (2000). Systemic intervention : philosophy, methodology, and practice. New York: Kluwer Academic/Plenum.
  • Mingers, J., & Rosenhead, J. (eds) (2001). Rational analysis for a problematic world revisited : problem structuring methods for complexity, uncertainty and conflict (2nd ed). Chichester: John Wiley & Sons Ltd.
  • Pidd, M. (2004). Systems modelling : theory and practice. Chichester: Chichester: John Wiley & Sons Ltd.
  • Pidd, M. (2010). Tools for thinking : modelling in management science (3rd ed). Chichester: John Wiley & Sons Ltd.
  • Sterman, J.D. (2000). Business dynamics : systems thinking and modeling for a complex world. Boston, Mass.: Irwin McGraw-Hill.
  • Vennix, J. (1996). Group Model Building: Facilitating Team Learning Using System Dynamics. Chichester: John Wiley & Sons Ltd.

Further Reading

  • Ackoff, R.L., & Emery, F.E. (1972). On purposeful systems. London: Tavistock Publications.
  • Coyle, R.G. (2004). Practical strategy : structured tools and techniques. Harlow: Financial Times Prentice Hall.
  • Friend, J.K., & Hickling, A. (2005). Planning under pressure: the strategic choice approach (3rd ed). Oxford: Elsevier Butterworth-Heinemann.
  • Jackson, M.C. (2003). Systems thinking: creative holism for managers. Chichester: John Wiley & Sons Ltd.
  • Midgley, G., & Ochoa-Arias, A. (2004). Community operational research : OR and systems thinking for community development. New York ; London: Kluwer Academic/Plenum.
  • Morecroft, J.D.W. (2007). Strategic modelling and business dynamics : a feedback systems approach. Hoboken, N.J.: Wiley
  • Ramage, M., & Shipp, K. (2009). Systems Thinkers. London: Springer.
  • Richardson, G.P. (1991). Feedback thought in social science and systems theory. Philadelphia: University of Pennsylvania Press.
  • Senge, P.M. (1990). The Fifth Discipline: The Art and Practice of the Learning Organization. London: Random House.

Hard Systems and Soft Systems

Hard Systems and Soft Systems

A frequent problem I come across when discussing hard and soft systems views with engineers is that the terms ‘hard’ and ‘soft’ are rarely defined clearly. Based on conversations I’ve had over the years at the University of Bristol a common position can be characterised by the statement “all hard systems are embedded in soft systems.” I used this myself in a CSER conference paper in 2011 when talking about the EngD in Systems programme where I teach. However, since then I have arrived at the position that the epistemic shift that Peter Checkland and Susan Holwell describe is a more useful way of characterising hard and soft systems views [1]. Instead of the rather vague association of soft with the social world, people, and human intentionality, the soft systems view moves away from this ontological commitment and treats the definition as a question of epistemology, i.e. what can we know or find out about the world? The following quote from [1] spells out this epistemological position in a way that I find compelling. It is:
“phenomenologist, social constructivist, avoiding ontological commitment – sees the perceived (social) world as: culturally extremely complex; capable of being described in many different ways; and sees the “system” as one useful concept in ensuring good-quality debate about intentional action. The two observers both agree that the notion “system” can be useful, O seeing it simply as a name for (parts of) the real world, E seeing it as a useful intellectual device to help structure discussion, debate and argument about the real world.”
Where observer O corresponds to the ontological position and observer E to the epistemological. This is all usefully summarised in a table that I use with my students adapted from the original in [1]:
Hard and Soft Systems Viewpoints

Checkland and Holwell’s paper appears in a volume edited by Michael Pidd [3], which brings together the ideas developed in the Interdisciplinary Research Network on Complementarity in Systems Modelling (INCISM) Network that was funded by the Engineering and Physical Sciences Research Council (EPSRC).

John Morecroft was part of the network too and in his work on System Dynamics modelling [2] reflects on how it should be used in this soft systems sense. He paraphrases Checkland to state “… system dynamics modellers do not spy systems. Rather they spy dynamics in the real world and they organise modelling as a learning process, with the project team, to discover the feedback structure that lies behind the dynamics“.

Reflections on this hard/soft complementarity and the work of the INCISM network at the System Dynamics conference in 2004 are captured in the notes from the record of the plenary session Working Ideas, Insights for Systems Modelling: The Broader Community of Systems Thinkers.

All of this is neatly summarised by Peter Checkland himself in a colloquium delivered at Lancaster University in 2012. In this short video, Checkland outlines the development of Soft Systems Methodology emphasising its role as methodology, not method, and the origin of this particular definition soft systems as the systemic learning system designed to help us deal with the complexity of the world.

[1] Checkland, P., & Holwell, S. (2004). “Classic” OR and “soft” OR – an asymmetric complementarity. In M. Pidd (Ed.), Systems Modelling: Theory and Practice. Chichester: John Wiley & Sons, Ltd.
[2] Morecroft, J.D.W. (2007). Strategic modelling and business dynamics : a feedback systems approach. Chichester : John Wiley & Sons, Ltd.
[3] Pidd, M. (2004). Systems modelling : theory and practice. Chichester: John Wiley & Sons, Ltd.