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 Briefing Paper One: Systems thinking

This briefing paper gives: the origins of systems thinking, a definition of systems thinking and of a system, the history of systems thinking and its major tenets, some of the major systems approaches, problems with systems thinking,  insights afforded by systems thinking, and references.


Systems thinking originated in the 1920s within several disciplines, notably biology and engineering, out of the observation that there were many aspects which scientific analysis could not explore. Whereas the scientific method (summarised by Popper as the three Rs: reduction, repeatability and refutation) increases our knowledge and understanding by breaking things down into their constituent parts and exploring the properties of these parts, systems thinking explores the properties which exist once the parts have been combined into a whole. The expectation of the systems thinkers of the 40s and 50s was that the scientific method would one day have two components: analytical thinking and systems thinking.

What is Systems Thinking?

Its essence is seeing inter-relationships rather than linear cause-and-effect chains, and in seeing processes of change rather than snapshots (Senge).

Systems thinking is a way of interpreting the universe as a series of interconnected and inter-related wholes. It is a way of identifying the inherent organisation within a complex situation and has been called organised complexity. Systems thinkers contrast dynamic complexity (the relationships between things) with detail complexity (details about things).

It is an approach, a set of general principles and specific tools and techniques, rather than a subject area in its own right; it can be applied within many different fields and is therefore described as a meta-discipline.

What is a system?

A system is a set of elements, connected together, which form a whole; this showing properties which are properties of the whole rather than of its component parts.(Checkland,).

There are four fundamental types of systems:
natural systems, e.g. a biological organism
designed physical systems, e.g. a building
designed abstract systems, e.g. a mathematical equation, and
human activity systems, e.g. a team engaged on a task, or a health care organisation

The last is seen as crucially different from the former three (Checkland) in that while the others can be described objectively and can be no other than they are human activity systems are understood differently by the various ‘human actors’ involved in them, who attribute different meanings to what they perceive. As long as each is logically consistent it is valid for the person making it and is therefore not right or wrong. Here objectivity has been described (Ackoff) as the social product of the open interaction of a wide variety of individual subjectivities.


Aristotle noted that the whole is greater than the sum of its parts but this concept became lost in the revolution in the scientific approach spearheaded by Newton in the 17th century. In the 1920s biologists noted organised complexity in the organisms they were studying. They observed a hierarchy of levels of organisation, each more complex than the one below it, with properties that emerge only at that level and do not exist (or have any meaning) at lower levels (Broad 1923, Smuts 1924 cited in Checkland).

Von Bertalanffy, in 1940, distinguished between open and closed systems; closed being completely autonomous and having no relationship with their environment; open exchanging with their environment materials, energy, and information. Closed systems are only to be found in the designed abstract class of systems, almost all of the systems that are of concern to health care professionals and managers will be open ones.

Also in the ’40s, Wiener and Bigelow, drawing on principles from control engineering and control theory and on their way to developing the field of cybernetics, realised the importance and ubiquity of feedback; activity within a system is the result of the influence of one element on another, that influence being called feedback. They identified positive and negative feedback; positive has since been called amplifying or reinforcing feedback and negative has been termed balancing feedback.

An example of positive/amplifying feedback could be the interaction of two new work colleagues. I behave in a an open and pleasant way towards you and you respond in a similar fashion. I become more open and begin to share work with you, and soon we are collaborating in a constructive way. If I had started by treating you with a distant smile and keeping all my thoughts to myself you would have chosen to cultivate a different colleague and my behaviour would have become more and more distant.

For an example of negative/balancing feedback look at any kind of thermostat, man made or biological.

In the ’50s a group of individuals from different fields came together to found the Society for the Advancement of General Systems Theory, and systems thinking became an academic subject, amassing a body of knowledge, an academic status, and the usual subdivision due to specialisation,

Systems Engineering developed in the 1950s, aimed at designing or changing (so that sense of engineering) systems. Originally the province of engineers working with designed physical systems, it soon became applied to human activity systems also. The process of systems engineering involves:

  • problem definition – articulation of the problem as seen by the engineer.
  • choice of objectives – expression of the desired state.
  • systems synthesis – written creation of possible alternative systems.
  • systems analysis – analysis of the hypothetical systems in light of the objectives.
  • system selection – of the ‘winning’ hypothetical system.
  • system development – further work on the chosen system.
  • current engineering – realisation in practice of the chosen system

At about the same time Systems Analysis was developed by the RanD Corporation in the States, drawing on the Operational Research expertise that had blossomed in military settings in WW2. This was at root a form of cost-benefit analysis and requires:

  • definition of objectives
  • identification or generation of alternative techniques to achieve those objectives
  • consideration of costs or resources required by the alternative options
  • development of a mathematical model showing the interdependence of objectives, techniques, environment and resources
  • articulation of the criterion, relating objectives and costs, for choosing the preferred alternative.

Both of these methods assume that there is an important class of real world problems that can be formulated as:

There is a desired state S1 and a current state S0, and alternative ways of getting from S0 to S1.

In other words it is assumed that the objective of the system is a given and that the role of the systems analyst or engineer is to work out how it can best be achieved. (Checkland)

When these methods were applied in social systems (for example to the public sector in the state of California in the early 1960s) the results were disappointing.

These methods, which all required the naming of the system and a defining of its objectives (Checkland), and in which the engineer or analyst stands outside the system intervening in it to try and reach a desired end, became known as Hard Systems.

During the 1970s, with the influential work of Ackoff, there became an increasing realisation that in human activity systems the system often cannot be ‘named’ convincingly, and that its objectives are frequently multiple and often conflicting. Ackoff introduced the term mess into the management science of the time:

    a puzzle is a conundrum to which there is an answer if you can only find it
    a problem is a conundrum to which there is no answer only better or worse approaches
    a mess is a dynamic system of problems

He suggested that much of management is about dealing with messes.

In the 1980s Checkland developed a methodology for working with Soft Systems, those where the problem does not lend itself to being quantified; in complex problem situations, messy, ill-defined, ill structured, not independent of people and where there may be no agreement about appropriate objectives (Daellenbach).

During the 1970s and 1980s much attention was paid to the modelling of systems, sometimes applying the notation developed in hard systems to soft systems, sometimes generating new ways of describing complex relationships. They all involve the following processes:

  • familiarisation with the system, often this requires some immersion within it.
  • a summary of the situation, which may identify a relevant system or a number of them.
  • a description of the relevant system which will include identification of the person whose viewpoint is being represented, definition of the boundary , identification of the desired outputs, inputs , and wider system of interest.
  • a representation of the system in the form of an influence diagram.

At the same period attention was paid to formulating the mess, in which the modelling of the system was only the first of three phases. Phase two is a mapping exercise in which the large number of factors obstructing achievement of the purpose of the system are categorised into a small number of classes. Phase three is ‘telling the story’ (Pourdehnad 1992) and involves ‘telling a believable and compelling story that reveals the undesirable future implicit in the current state… and leads to a desire for change’.

System Design also originated in the 1970s and has been developed further since. It is based on the observation (e.g. by Churchman, 1971) that the best way to learn a system is to design it. The process requires that it be assumed that the system to be redesigned has been destroyed overnight, but everything in its environment remains the same. The challenge is to design it from scratch such that:

  • there is a huge increase in throughput
  • the process leads to a shared understanding among critical actors
  • it generates ownership and commitment
  • conflict is dissolved
  • obstructions are converted into opportunities.

In the 1980s and 1990s systems thinking was popularised (i.e. made more accessible to practising managers and others) largely by Peter Senge of MIT. It was incorporated into a wider field of study about individual and organisational learning, heavily influenced by the work of Chris Argyris and David Bohm. One of the major contributions of this work has been the identification of systems archetypes i.e. influence patterns that can be found in many different systems. The two most widely known of these are the Limits to Growth archetype, and the Shifting the Burden archetype. They are well described in The Fifth Discipline.

More recently still the combination of using large group interventions with applying some of the insights of systems thinking has led to a field of activity known as Whole Systems . In the UK Plamping, Pratt and Gordon have worked with Whole Systems principles in intractable problems that involve health and health care. The systems they have explored involve many stakeholders, e.g. health and other statutory agencies, users, communities and voluntary organisations. Along the way the term whole systems has become misapplied, and is now commonly used instead of the term system-wide.This is a loss, as the richness of the original usage is often not understood or used.

Problems with Systems Thinking

The development of Chaos Theory has demonstrated that the early systems thinkers were over ambitious in their belief that the dynamics of a system could be completely analysed. We now know that complex, dynamic systems can be extremely sensitive to initial starting conditions, (the butterfly wing over the pacific), and we realise that a such a system is unlikely to yield to analysis in this way. This does not mean that systems thinking is no longer useful, nor that it has been superseded by complexity theory. Systems thinking is a crucial component of complexity theory and many of the insights that are now labelled ‘complexity’ are classic systems concepts. Indeed since we are usually trying to consider how to intervene in a system ( a human activity system) rather than to define it with complete accuracy, the insights afforded by soft systems thinking are often as useful as any.

Insights afforded by Systems Thinking.

  1. Wholes have properties that are the properties of the whole and not of the parts. This means that dividing an elephant in half does not produce two small elephants.(Senge).

    We cannot understand a wider system by looking in detail at its parts, because some properties only emerge when they are combined together. So if we want to understand, e.g., how a patient experiences a service, we cannot find that out by considering only the consitituent parts, we need to look at the whole patient journey (across organisational boundaries).
  2. Components of a system interact with each other in a reciprocal flow of influence, and in most management situations understanding this dynamic complexity is more important than understanding detail complexity. These inter-relationships mean that cause and effect are not closely related in time and space, and that the results of any intervention in a system may well be unexpected.

    As a result, any interventions we make will have many effects we did not predict or expect, in parts of the system we were not aware of influencing.
  3. A system also interacts with its environment, and the behaviour of a system can only be understood in the context of its environment. The environment can be thought of in two parts: the environment over which the system does not exert power but does have some influence (sometimes known as the wider system of interest); and that over which it has no influence. 

    We therefore need to be able to describe the environment, and the influence that it has, of any service or system we are interested in.
  4. A system always has a purpose. Sometimes the purpose is evident to/ shared by  all; sometimes the purpose differs in the perceptions of people who are involved in it. Every human actor in a system brings to the system their understanding of its purpose and their view on the world (or weltenschauung). This view consists of three elements: rational, emotional and cultural.

    It is crucial therefore to understand these ‘weltenschaungen’. To do so requires an understanding of organisational behaviour and psychology.
  5. Systems stabilise in equilibrium and they require a source of energy if this equilibrium is to shift, i.e. if there is to be change. The energy can come from outside the system (in which case the approach is a hard systems approach) or from within it  (a soft systems approach). In a hard systems approach an outsider will identify a purpose, a measure of performance, the decision making processes, the resources to be made available to the decision makers, the boundary between the system and its environment, and the system dynamics (inputs, outputs and relationships between components. In a soft systems approach the people within the system are encouraged to articulate their personal perceptions of the purpose, measures of performance, the boundary, inputs, outputs etc.

    When intervening in a system it is important to identify this source of energy and its nature.
  6. Multi-purpose, multi-structural, multiple process systems, such as those that characterise health care, are too complex for anyone to understand fully.

    In systems like this the players within them must be able to reflect on the system, learn from its performance and make changes.
  7. Systems nest within systems and the inter-relationships across an organisation must betaken into account when a change intervention is planned.

    This means that organisation-wide approaches are sometimes required.
  8. Dynamic complexity can be modelled, using notation that expresses positive and negative feedback, and the insights gained from this process can be used in the redesign of the system.

    An understanding of interdependencies can be used to enhance the effectiveness of implementing change. Network diagrams are a means of doing so.


Ackoff RL, 1970 Redesigning the Future. A Systems Approach to Societal Problems. New York, Wiley.
Checkland P,1981 Systems Thinking, Systems Practice. New York, Wiley
Daellenbach H G, 1994 Systems and Decision Making. A Management Science Approach. Chichester, Wiley.
Pourdehnad J, cited in Gharajedaghi J, 1999 Systems Thinking: Managing Chaos and Complexity. A platform for designing business architecture.Woburn Mass, Butterworth-Heinemann
Pratt J, Gordon P, Plamping D, 1999 Working Whole Systems. Putting theory into practice in organisations. London Kings Fund Senge P, 1990 The Fifth Discipline: the art and practice of the learning organisation.London, Century Business