Systems thinkers and their approaches

How systems thinkers came to eviscerate the system

Copyright 2017 Graham Berrisford. One of about 300 papers at Last updated 19/11/2017 20:01


This paper analyses a three-way classification of systems thinking approaches.

It challenges the classification and proposes an alternative view.


Preface. 1

System thinking approaches. 2

Classical general system theory and cybernetics. 3

Class 1: “Hard systems thinking” approaches. 6

Class 2: “Soft systems thinking” approaches. 10

Class 3: “Critical systems thinking” approaches. 16

Is the three-way classification a progressive history?. 17

Afterthoughts. 18



In the 1950s, von Bertalanffy, Ashby and others looked for patterns and principles common to systems across all sciences.

General system theory (GST) is supposed to be applicable to systems in every field of research, at every level of nesting.

Bear in mind that systems stretch from the sciences to the humanities (maths > physics > chemistry > biology > psychology > sociology > politics).


Ashby saw a system as an island of orderly behavior in the ever-unfolding process that is universe.

He said the scope of a system is determined by its describers.

Give some aims or interests, describers focus on some regular behaviors performed by some interacting entities.

Ashby’s system might be characterised, very briefly, as a describable set of role and rules.


In the 1970s, some sociologically-inclined systems thinkers found the constraints of Ashby’s ideas as too limiting.

These papers explore the result, which is schismatic distinction between:

·         a social system - in which actors realise roles and rules (describable in accord with GST and classical cybernetics)

·         a social entity - in which actors choose their own behaviors to reach agreed goals (as discussed in second order cybernetics).


All terms defined thus (Term: definition) are copied from this glossary, where they are defined more fully.

This paper includes links to papers that explain particular concepts in more detail.

A 3-way classification of system thinking approaches

Ackoff was a well known sociologically-inclined systems thinker who wrote: “There are many different ways of classifying systems.” Ackoff 2003.

A naive classification, for example, could divide systems into machines, organisms and societies.

Social systems thinkers like to classify not only systems, but also approaches to thinking about systems and solving problems.


This three-way categorization is copied from another source.

Class 1: Hard systems thinking approaches

Class 2: Soft systems thinking approaches

Class 3: Critical system thinking approaches

1956 General Systems Theory (Bertalanffy)

1956 Classical (classical) cybernetics (Ashby)

1957 Operations research (Churchman et al.)

1962 Systems engineering (Hall)

1963 Socio-technical systems (Trist et al.)

1965 RAND-systems analysis (Optner)

1971-72 System Dynamics (Forrester; Meadows et al.)

1971 Inquiring systems design (Churchman).

1972 Second order cybernetics (Bateson)

1972 Soft systems methodology (Checkland)

1981 Interactive management (Ackoff)

1981 Strategic assumption surface testing (Mason and Mitroff)

1988 Cognitive mapping for strategic options development and analysis (Eden)

1983 Critical system heuristics (Ulrich)

1990 System of systems methodologies (Jackson)

1990 Liberating systems theory (Flood)

1991 Interpretive systemology (Fuenmayor)

1991 Total systems intervention (Flood and Jackson)

2000 Systemic intervention (Midgley).


This paper:

·         reviews this classification, with reference to several of the authors listed.

·         looks at each kind of approach with reference to terms and concepts of general system theory and classical cybernetics.

·         challenges using the labels “hard” and “soft” to distinguish classes 1 and 2, and proposes a different, more schismatic, distinction.

·         challenges the proposal that class 3 is an advance on class 2 which is an advance on class 1.

·         presents some kinds of system thinking as departing from general system theory and eviscerating the concept of a system.


Remember, it is easy confuse classifications of systems with classifications of system thinking approaches.

This paper regards a people using a systems thinking approach as a meta system to any system that they analyse or design.

Classical general system theory and cybernetics

Before discussing systems thinking approaches, the basic ideas of general system theory ought to be set out.

“The principal heuristic innovation of the systems approach is what may be called ‘reduction to dynamics’ as contrasted with ‘reduction to components’ ” Laszlo and Krippner.

Bertalanffy: general system theory

Ludwig von Bertalanffy (1901-1972) was a biologist who established the idea of a general system theory, soon after the second world war.

He looked for what is common to systems in different sciences.

You may recognise that systems are generally described in terms of aims (motivations), behaviors (processes) and structures (actors or components).


This table illustrates these general system concepts.





Win the world cup

Target outcomes, which give an actor a reason or logic to select and peform behaviors.


Compete in world cup matches

Processes, which run over time towards a final aim.

Active structures

Players in a national football team

Nodes (related in a hierarchical or network structure) that perform activities in behaviors.

Passive structures

Pitches, footballs

Objects acted upon during behaviors.


There are other general system concepts.

“Systems concepts include: system-environment boundary, input, output, process, state….”   Principia Cybernetica

System environment: the world outside the system of interest.

System boundary: a line (physical or logical) that separates a system from is environment

System interface: a description of inputs and outputs that cross the system boundary.

Information theory

Bertalanffy related GST to communication of information between the parts of a system and across its boundary.

“connected with system theory is… communication. The general notion in communication theory is that of information.” Bertalanffy


Information: a meaning created or found by an actor in any physical form that acts as a signal.

Any description or direction that has been encoded in a signal or decoded from it by an actor.


Signal: any structure of matter or energy flow in which an actor creates or finds information.

In human communications, the physical forms include brain waves and sound waves.

In digital information systems, the physical form is a data structure in a binary code.


Information flow (aka message): physically, a signal passed from sender to receiver, logically, a communication.

Information state (aka memory): see “state”.

Information quality: an attribute of information flow or state, such as speed, throughput, availability, security, monetary value.

Weiner: cybernetics

Norbert Wiener (1894-1964) founded cybernetics – about how regulators monitor and control behaviors using feedback loops.

Information feedback loop: the circular fashion in which system inputs influence future outputs and vice-versa.


In 1948, he published Cybernetics or Control and Communication in the Animal and the Machine.

The phrase “control and communication” highlights the importance of information flows.

The phrase “the animal and the machine” suggest the principles apply to both animate (inc. human) and inanimate (inc. computer) systems.


Cybernetics has influenced systems thinking in general, and business system thinking in particular.

Nowadays it seems trite point out that a business system is connected to its wider environment by feedback loops.

It monitors and directs entities in its environment; and gathers, stores and produces information to do this.

Ashby: cybernetics

W. Ross Ashby (1903-1972) was a psychologist and systems theorist.

“Despite being widely influential within cybernetics, systems theory… Ashby is not as well known as many of the notable scientists his work influenced.

W Ross Ashby was one of the original members of the Ratio Club, who met to discuss issues from 1949 to 1958.” Wikpedia 2017


In “Design for a Brain” (1952), Ashby presented the brain as a system.

He eschewed discussion of consciousness; his basic idea might be distilled into one sentence thus.


Generic system description

Ashby’s design for a brain

A collection of active structures

that interact in regular behaviors

that maintain system state and/or

consume/deliver inputs/outputs

from/to the wider environment.

A collection of brain cells that

interact in processes to

maintain body state variables by

receiving/sending information

from/to bodily sensors/motors.


In short

A system is a view of a reality; or a role you can observe or envisage real world entities as playing.

To apply system theory is to form an abstract system description that hides the infinite complexity of real-world entities you observe or envisage.

You describe the state of a real-world system in terms of variables whose values can be measured (e.g. the positions of the planets).

You model whatever regular processes can change the values of those variables (e.g. the orbits of the planets).

You describe a process in a way that enables real world behaviors to be tested as matching your description.


Ashby’s ideas are so fundamental to systems thinking that it is recommended you read Ashby’s ideas .

Forrester: System Dynamics

Forrester (1971) promoted System Dynamics as tool for system observers to describe system behaviors in terms of stocks and flows.

A stock is a dynamic set of things – it has a number of members - a quantity - a stock level.

A flow between two stocks represents events that change stock levels over time.


The state of one very narrow ecology can be described in terms of two variables: the quantity of sheep and the quantity of wolves.

Forrester’s System Dynamics helps to explain how these stocks interact.

It employs the idea of causal loop between what Engels might call opposites.


A growth in the stock of


will increase the stock of


A growth in the stock of


will deplete the stock of



The state of the wider world’s ecology can be described in terms of three variables: the mass of plants, the mass of animals and the mass of oxygen in the atmosphere.

We all depend on the fact that plants and animals balance the stock of oxygen.

Forrester’s System Dynamics helps to explain how these stocks interact so as to reach a balance.


A growth in the stock of


will increase the stock of


A growth in the stock of


will deplete the stock of



However, not all processes and feedback loops act to keep a system stable.

A system may deplete a stock to zero, or increase a stock continually; and this kind of instability may be desirable.

A system may exhaust a resource it needs: E.g. A moon rocket exhausts its fuel in a few minutes.

A system can continually expand or grow in some way: E.g. A business increases its revenue every year.


Note: the long-term impact of many interactions between two populations can be “chaotic” rather than homeostatic.

For more, read Modelling a continuously varying system using System Dynamics.

Systems as conceptualizations

Many systems thinkers fudge the distinction between system descriptions and physical realizations of them.

Abstract system description: a description or model of a concrete system.

Concrete system (aka System): a system that runs in reality (and is testable against its description).


Ashby was keen we separate abstract system descriptions from concrete entities that realise them.

“Cybernetics depends in no essential way on the laws of physics or on the properties of matter.” Ashby 1956

He said a real-world entity is not a system per se; it is only a system in so far as it performs the behaviors in an abstract system description.


Abstract system description

Theoretical system

System description

Concrete system realization

An empirical system

Real world behaviors


This triangle further separates system describers from system descriptions and the real world behaviors they observe.

Ashby’s cybernetics

System descriptions

<create and use>                  <realised by>

System describers <observe and envisage> Real world behaviors


For example, we can separate the US founding fathers (and their successors) from the US constitution and its realization by actual federal governments.

US government system

US constitution

<amends>                    <realised by>

Constitutional convention <observes & envisages> US governments


The US constitution defines the roles and rules of the essential actors in the US federal government system.

The roles include the Congress (the legislative branch), the President, the court system (the judicial branch) and the States.

It also defines relations between actors playing those roles.

(It does not define the roles or rules of subordinate institutions created by federal governments.)


Different people may conceptualise the same named entity as different systems - or no system at all.

A particular (concrete) federal government is a system when its actors performs behaviors described in the generic (abstract) US constitution.

However, the same federal government may perform other behaviors, and may be conceptualised from a different perspective as a different system.


Note: The US constitution also defines the meta system to be used (by Congress or Constitutional Convention) to amend the constitution.

Class 1: “Hard systems thinking” approaches

A “hard” systems thinking approach applies ideas found in general system theory (after Bertalanffy) and classical cybernetics (after Weiner and Ashby).

How does a “hard” systems thinking approach work?

Hard systems thinking can be applied to natural systems, but is more often discussed in terms of designed systems.

Natural system: a system that runs before it is described by man.

Designed system: a system described by man before it runs.


System design typically runs from requirements analysis, through system description, building and testing to roll out.

Even mechanical systems are designed to meet different goals, some of which conflict.


This table generalises from hard system design processes taught to mechanical engineers and business system architects.

A hard system thinking methodology

Study the context: goals, constraints, stakeholders, their concerns, problems and requirements

Outline optional solution visions, along with value propositions for stakeholders

Analyse trade offs between solution options with respect to the context

Describe a target system that compromises between conflicting goals and constraints

Plan the work to move from the current to the target system

Follow the plan to build and test the target system

Roll out the target system.


Note: the fact that stakeholders approve a target system description doesn’t mean they share the same perspective of, or purpose for, the system.

Each may have their own perspective and value proposition.

Boulding: system theory in management science

Bertalanffy, Boulding and others established the Society for the Advancement of General Systems Theory in 1954.

Kenneth Boulding (1910-1993) wrote in 1956 about applying GST to “management science”.


Boulding on society

Boulding described social systems at two levels, populations and individuals.

He said behaviors performed by an individual include

·         joining or leaving a population

·         processing information and communicating meaning to others

·         remembering and acting on mental images (internal state data)

·         transcribing mental images into historical records and

·         restoring system state to some kind of norm.


In system theory terms, Boulding’s society of humans might be described thus.


Generic system description

Boulding’s social system

A collection of active structures

that interact in regular behaviors

that maintain system state and/or

consume/deliver inputs/outputs

from/to the wider environment.

A population of individuals that interact by

processing information in the light of

mental images they remember, and

exchange messages to communicate meanings

to others and related populations.


Boulding on individuals as deterministic

Like many early systems thinkers, Boulding was concerned with how systems maintain their state.

System state: the current structure or variables of a system, which may change over time.

Deterministic: the quality of a system that means its next state is predictable from its current state and input event.


A deterministic system, in a given state, will respond to a stimulus by acting in a predictable way.

In the 1950s, Ashby wrote that the notion of a deterministic system was already more than century old.

Sociologists, biologists, psychologists and control system engineers all describe deterministic systems.





In the light of



respond to chemical/electrical signals

their current chemical state.

Machine regulators


send messages to devices

messages received about environment state changes.



perform operations in response to messages

current state variable values.

Entity/event models


change state in response to events

current state variable values.

System dynamics


change volume in response to event flows

current stock volumes.



communicate in response to messages

their memories (or “mental images” as Boulding called them in 1956).


Boulding presumed that a human actor, in a given state, will respond to a stimulus by acting in a predictable way.

He said the difficulty with applying GST is that an actor’s state data (their “mental images”) is unknowable.

And since you cannot know the state of an actor, you cannot predict an actor’s response to an event.


Boulding didn’t mention that distributing a population’s state data between individual actors makes it hard to maintain the integrity of a population.

And difficult to collect management information about it.

(Just as distributing a software system’s state data between individual objects makes it hard to maintain the integrity of the system, and collect management information).


Boulding on social systems as complex

Boulding classified systems into nine kinds, presenting them on a scale from “simple” to “complex”.

He placed social systems at level 8, below “transcendental” systems at level 9.

Beware! Terms are used glibly in systems thinking discussion, sometimes contrary to how a scientist would use them.

When listing system types from simple to complex, Boulding presumed that a higher or wider system must be more complex than its component subsystems

And particularly, that human social systems are an especially high level and complex kind of system.


Boulding’s presumptions do not hold

First, because there is no recognised way to measure the complexity of a thing.

Bertalanffy said system elements can be counted.

“In dealing with complexes of 'elements', three different kinds of distinction may be made: according to their number; their species; the relations of elements.” von Bertalanffy

But there is no agreement about how the counting system elements and relationships (types and/or instances) could be used to measure complexity.


More importantly, you can only measure what you can describe.

And the internal structure of atomic elements in a system description must be ignored.

Describers relate the atomic structures (actors) in larger structures, and relate atomic behaviors (actions) in longer processes.

The system’s complexity is found in how atomic elements are organised in higher structures and longer processes.

It is not only normal but necessary to disregard the internal complexity of atomic elements when measuring the complexity of a whole system.

And thus, a higher or wider system can be simpler than its component subsystems.


Boulding on roles and actors

The actors in examples above are not dedicated to any one system; they can act (in different roles) in countless higher/wider systems.

The “parts” of an active social system are not so much the actors, as the performances by those actors of actions in system roles.

Like Weber before him, Boulding suggested the essential business system element might be roles rather than actors.

But whether he took a role-centric or actor-centric view of systems was not entirely clear.

And ever since Boulding, social systems thinkers have tended to confuse those two viewpoints.

Is a “hard” systems thinking approach related to any particular system class?

Gerald Midgley (2000) said “hard” systems thinking is about systems classifiable as having a “unity of purpose”.

Yet the purposes of a thing are subjective; and even to one observer, a thing can have different purposes in different contexts.

A cuckoo clock that fails to keep time well may be cherished for its alarm function, or its charming design.


Bausch (2001) alluded to Churchman, Ackoff and Checkland as the triumvirate who created the “soft systems methodology”, wrote:

“[They] consider hard systems methodology to be a special application of systems theory in situations where the objectives are not in question”

Yet the objectives of system sponsors, stakeholders and individual participants are well-nigh always questionable.

Even mechanical engineers are taught to manage stakeholders and trade off between conflicting goals.

It would be more accurate to say the reverse, that social system theory (SST) is a special version of general system theory (GST).

The unforeseen success of GST ideas in the digital transformation of business processes

It is said that the most complex system in nature is the human brain.

By any measure, today, the most complex systems humans design are software systems.

And (unforeseen by Bertalanffy, Weiner and Ashby) software systems are applications of their core GST ideas.


Generic system description

An object-oriented software system

A collection of active structures

that interact in regular behaviors

that maintain system state and/or

consume/deliver inputs/outputs

from/to the wider environment.

A population of objects that interact by

processing information in the light of

state data they remember, and

exchange messages to communicate

with other objects and system users.


We don’t require that every concrete activity system matches an abstract system description perfectly.

But software systems are perfect in the sense that, at run time, they can do only what is described in their code.


As in classical cybernetics, a software system is typically designed to monitor and/or inform entities in its environment.

This has enabled the information feedback loops that connect a business with entities in its environment to be digitised.

Thus, the application of GST ideas in software systems has had a profound impact on society.

The regular behaviors of businesses and other social systems have increasingly been automated, supported and enabled by computers.

Half a century after we entered the “Information Age”, people talk of using software systems to make “digital transformations”.

In the future, transformations will increasingly involve artificial intelligence.

Class 2: “Soft systems thinking” approaches

Most soft systems thinking is about a government or business system in which the actors include humans.

Soft system thinking approaches are designed for use by the analysts, designers and planners of these systems.

The aim is to help them to study a problem situation, capture requirements, model systems and propose changes to them.


Churchman, Checkland and Ackoff were notable contributors to soft systems thinking.

Churchman initially wrote for actors in what was then commonly called the operations research department.

Operational researchers act as a meta system to business systems.

They study regular business operations and propose how to optimise or otherwise change them.


Operational research

System descriptions

<create and use>                    <realised by>

Operational researchers <observe and envisage> Business operations


Hmm… this triangle looks like the one for Ashby’s cybernetics.

This section challenges the notion that soft systems thinking is significantly different from the “hard system thinking methodology” outlined above.

It points to “second-order cybernetics” as being far more significantly different.

Soft systems

The term “soft system” can be read as having two very different meanings.

·         an empirical or concrete system in which human actors play roles.

·         a theoretical or abstract system, described by an individual or group.


Just as Ashby said infinite theoretical/abstract systems may be abstracted from any empirical/concrete entity.

So, Checkland defined a system as a perspective of a reality, a world view or “Weltenshauung”.


Checkland (1981, p. 102.) wrote:

“Implicit here is the notion that an observer engaged in systems research will give an account of the world, or part of it, in systems terms;

·         his purpose in so doing;

·         his definition of his system or systems;

·         the principle which makes them coherent entities;

·         the means and mechanisms by which they tend to maintain their integrity;

·         their boundaries, inputs, outputs, and components;

·         their structure.”


The table below maps that definition, along with those of Ashby, Boulding and object-oriented software, to one Generic system description.

Generic system description

Ashby’s design for a brain

Boulding’s social system

Checkland’s Soft System

An object-oriented software system

A collection of active structures

that interact in regular behaviors

that maintain system state and/or

consume/deliver inputs/outputs

from/to the wider environment.

A collection of brain cells that

interact in processes to

maintain body state variables by

receiving/sending information

from/to bodily sensors/motors.

A population of individuals that interact by

processing information in the light of

mental images they remember, and

exchange messages to communicate meanings

to others and related populations.

A coherent entity, a structure of components

that interact in mechanisms that

maintain the integrity of the entity and

consume/deliver inputs/outputs

from/to each other and external entities.

A population of objects that interact by

processing information in the light of

state data they remember, and

exchange messages to communicate

with other objects and system users.


All four specific cases fit the generic system description reasonably well.

And in all cases, the real world entity is regarded as a system in so far as it realises a system description.


So, is there any significant difference between hard and soft systems?


After several decades, Checkland wrote "Soft Systems Methodology: A Thirty Year Retrospective" (2000)

In his review, he said the hard-soft distinction had proved slippery; people grasp it one week and lose it the next.

He said the term "soft" was intended to describe not systems, but an approach to solving problems in human activity systems.

Which brings us to his approach - his methodology.

Soft systems methodology

Checkland developed a soft systems methodology (SSM).

Looked at in terms of general system theory, SSM is a very specific approach:

·         specific to systems that are open rather than closed

·         specific to designed rather than natural systems

·         specific to systems in which the actors are human - human activity systems

·         specific to human activity systems with owners and customers - business systems.


Some see SSM as “situation thinking” rather than “systems thinking”.

However, the aim is to model some regular behaviors in a business, and change them from a baseline (problematic) state to a target (improved) state.

The table lists the seven steps of SSM against the steps in a typical hard systems thinking methodology.

The steps do not correspond one for one, but the difference are mostly cosmetic, a matter of emphasis or of particular technique.


A typical hard system thinking methodology

Soft Systems Methodology

Study the context: goals, constraints, stakeholders, their concerns, problems and requirements

Enter the problem situation.

Outline optional solution visions, along with value propositions for stakeholders

Express the problem situation (a rich picture)

Analyse trade offs between solution options with respect to the context

Formulate root definitions of relevant systems (validated using the CATWOE analysis below)

Describe a target system that compromises between conflicting goals and constraints

Represent human activity systems as conceptual models (business activity models)

Plan the work to move from the current to the target system

Compare the models with the real world.

Follow the plan to build and test the target system

Define changes that are desirable and feasible

Roll out the target system.

Take action to improve the real world situation.


Root definitions

The following example adapted is from

“A company owned system to market the products and services of the company to existing and future clients by the most appropriate cost effective means.”

The source above analyses that root definition using Checkland’s CATWOE acronym as below:




Entities that receive outputs from the transformation

“existing and future clients”



Entities that do or could perform activities in the transformation

“the company”



Activities that transform input to outputs

“Market the products and services of the company”


World view

The belief that makes sense of the root definition

Providing appropriate marketing to a particular client will promote company products and services



The decision maker concerned with system performance

“the company”



Constraints outside the system significant to the system

“appropriate cost effective means”


The “system” is primarily the Transformation, and the roles of Actors in that.

Forming a "root definition" of a whole business entity is only partly related to general system theory.

A truly general system theory does not feature Customer, World view or Owner.

One can form several root definitions of one business entity - even the Customer can be debatable.

Uncovering such different view points can be valuable in itself.

While CATWOE is a useful tool, each root definition is a particular view of a business.

And focusing on CATWOE may underplay the importance of Outputs, Inputs and Suppliers, if not also measurable Objectives.


Conceptual models

Checkland proposed modelling the Transformation in an abstract and informal “conceptual model”.

This model of the Transformation – of the operational business system – takes the form of a business activity diagram.

It shows transformation activities connected by dependency arrows.

To this very abstract model of business operations, two layers may be added:

·         Regular operations management: a control system to set aims for, monitor and direct the transformation activities.

·         Overarching executive/governance: a meta system to set aims for, monitor and control the regular operations management.


Thus, Checkland proposed a generic design pattern for structuring a business in terms of essential functions.

·         defining targets (system aims)

·         operations (system behaviors)

·         monitoring and controlling of operations (cf. system regulation as in classical cybernetics).


Of course, the same ideas can be found in many approaches.

Beer proposed a more complex design pattern, called the Viable System Model.

Beer: the Viable System Model

Stafford Beer (1926- 2002) was a theorist, consultant and professor at the Manchester Business School.

He regarded Ashby as a grandfather of cybernetics (I believe Ashby was a godfather to one of Beer’s children).

He respected Ashby, but was focused more on what might be called “management science”.

So, he set out to apply Ashby’s ideas to business systems.

His book title “Brain of the Firm” (1972) may well be a deliberate echo of Ashby’s “Design for a Brain” 20 years earlier.


In “Diagnosing the system for organisations” (1985) Beer detailed his “Viable System Model”.

He said the VSM was inspired by the structure of the human central nervous system.

Actually: it doesn’t resemble the known structure or workings of the human brain or nervous system.

And it cannot be the VSM, since many viable systems have nothing like a central nervous system (e.g. the solar system, a tree, a bee hive, an oyster).

The VSM is a tool for diagnosing human organization design issues, and generating change proposals.

Read Ashby’s ideas – and Beer’s use of them for more.

The trouble with the hard-soft distinction

The soft systems thinking approaches above are not much different from the “hard system thinking methodology” outlined above.

Because all systems-of-interest are perspectives of reality.

And all system design methodologies involve capturing different perspectives, drawing abstract designs and trading off between different objectives.


Checkland proposed SSM starts not with spotting a system to be reengineered but with spotting a confusing or complex situation.

OK, but these are not mutually exclusive starting points – and the end product is indeed a re-engineered human activity system.


Checkland said he designed SSM as a “learning system”.

OK, but all traditional system design methodologies include activities intended to help designers learn about the context.

And it is important not to confuse the meta system with the system.

Defining a systems thinking approach as a learning system is very different from defining the target system as a learning system.


Which leads us towards “second order cybernetics”.

Checkland observed the distinction between hard and soft system approaches is slippery.

By contrast, the distinction between classical and second order cybernetics is schismatic.

Social entities v social systems

You could say general system theory is primarily about the roles in a symphony (the system).

Whereas, modern “systems thinking” is much about the actors in the orchestra, and their motivations.


Social system: a system in which animate actors play roles in regular, repeatable processes.

E.g. bees collecting pollen for a beehive; an orchestra’s performance of a symphony.

The symphony score is a system description; every performance of that symphony instantiates that system description in reality.


Social entity: a group of actors who may chose their own behaviors, and may interact to reach agreed aims.

E.g. the group of actors hired to play in an orchestra, who may agree to hold a party after the performance.


People often point at an identifiable entity and call it “a system”.

However, a social or business entity can realise very many unrelated and uncoordinated behaviors.

E.g. one social group can realise the two behaviour types “card game” and “dinner party”.


System types

 “Card game”

“Dinner party”

System instances

A game of bridge

A game of whist

A dinner

Social entity

The social group: John, Joe, Joan and Jo


A business can be seen as a social entity in which actors play roles in many systems

Those business systems may be inconsistent, unrelated, or even in competition with each other.

To study all the behaviors an entity realises is impossible, and the attempt is never made.

Systems theory involves selecting and studying those behaviors of an entity that are relevant to some given purpose(s) or interest.

Ackoff: human organizations as purposeful systems

Russell L Ackoff (1919-2009) was an American organizational theorist, operations researcher, systems thinker and management scientist.

He blurred the distinction between social systems and social entities (and so, between classical and second order cybernetics).


In“System of System Concepts” (1971), Ackoff began by endorsing Ashby’s and Checkland’s point that a system is a conceptual model of reality.

“Different observers of the same phenomena may conceptualise them into different systems” Ackoff

In other words, observers of one named social entity may describe it as different systems.

Later, Ackoff contradicted himself about the nature of systems: “A church, a corporation or a government agency is a system”.

In other words, one named social entity is one system, regardless of any observer or conceptualization.

Thus, Ackoff confused social systems and social entities.


Ackoff’s four-way system classification (which evolved from 1971 to 2003) had some curious features.

E.g. his “animate systems” exclude lower animals; his “social systems” exclude non-human social groups.

But like most social system thinkers, his focus was on human organizations of the kind discussed in “management science”.


What did Ackoff mean when he said “All organizations are social systems”?

His primary interest was organizations that employ human actors.

But he was not concerned with informal organizations that have little or no bureaucracy (e.g. a pick-pocket gang, or a choir).

By “organization” he meant a hierarchical bureaucracy that administratively organizes people and their work - in the public or private sector.

And like others in the 1970s, Ackoff considered government institutions to be on the point of collapse.


Social systems thinkers presume any such organization or institution can be called a “system”.

Ackoff classified them more particularly as “purposeful systems”.

Meaning that people employed in organizations (being self-aware) have their own purposes, which shape what they choose to do.


In 1972, Ackoff wrote a book with Emery about purposeful systems which focused on how systems thinking relates to human behavior.

He defined a human-created system as "purposeful" when its "members are also purposeful individuals”.

These individuals intentionally and collectively formulate objectives and are parts of larger purposeful systems.

He said a purposeful system or individual is also ideal-seeking if it chooses objectives that lead towards as wider and more strategic ideal.


Thus, Ackoff promoted a kind of systems thinking that is special to human organizations (rather than general).

"The capability of seeking ideals may well be a characteristic that distinguishes man from anything he can make, including computers".


Again, there is a schismatic distinction between:

·         social systems in which actors’ roles and rules are describable

·         social entities in which actors choose their own behaviors in pursuit of some ideal they share.


Like many social systems thinkers, Ackoff tended to blur the distinction.

After all, his concern was not to design system roles and rules in detail; he expected system actors to change their behaviors.

His agenda was to rather to bemoan the state of institutions, diagnose problems in them and propose interventions to change them.


Ackoff’s view


<propose>                      <to reorganise>

System thinkers <observe and envisage> Purposeful organizations

Bateson: second order cybernetics

Bateson (1972) introduced second order cybernetics.

This allowed that system actors can observe the outcomes of past behaviors and choose their own future behaviors.

Like Ackoff, he viewed a social system as containing not only system actors but also systems thinkers.


GST and classical cybernetics focus attention on system behaviors ahead of system structures.

And they define systems in terms of general roles rather than individual actors.


Second order cybernetics is radically different from classical cybernetics.

It shifts attention from behaviors to their purposes (aka goals, objectives, targets).

And from abstract roles to individual actors, who each have their own purposes.

Class 3: “Critical systems thinking” approaches

Simply speaking, systems thinking involves four activities

1.      forming a model of a current system (N): analysing, discussing and criticising it, envisaging changes

2.      creating a model of a target system (N+1): discussing, reviewing and agreeing it

3.      planning the change from system N to system N+1.

4.      working to change system N to system N+1.


Of course, mental models are fragile and difficult to share.

So, formalising a systems thinking approach involves documenting mental models for discussion and agreement with others.

The approach should recommend the kinds of model you can or should document

And it should recommend techniques such as stakeholder management and risk management.


You can recognise all the ideas above in both hard and soft systems thinking approaches.

So what does a critical systems thinking approach add?


Gerald Midgley (2000) presented critical system thinking approaches as a post 1980 development of hard/soft systems thinking approaches.

The terms “total” and “systemic” (in the book titles he listed) imply these approaches lead to a root and branch transformation.

If not a revolution, the result is a major generational change from a current state of being to a new state of being.


The term “critical” is usually associated with approaches developed since 1980.

However, I am told “critical theory” emerged from the Frankfurt school of sociology, which came to prominence in the 1930s.

Largely a Hegelian invention, the word “critical” implied a dialectic, a logical investigation or discussion of the truth of propositions.


Ulrich (1983) may well have been thinking of critical theory when he added the word “critical” to “systems thinking”.

He defined three heuristics of the approach.


·         Making sense of the situation: understanding assumptions and appreciating the bigger picture

·         Unfolding multiple perspectives: promoting mutual understanding.

·         Promoting reflective practice: analysing situations – and changing them.


Yet traditional systems analysis and design methods start with understanding the context and motivations.

They stress the importance of stakeholder management and viewpoints.

E.g. TOGAF recommends defining views and value propositions for each stakeholder group.

And they involve analysing the current situation and considering changes


So again, what essential difference is there in a critical systems thinking approach?

One reader has suggested encapsulation of systems.

Again, agreeing the boundary of a system (expanding it, contracting it, or shifting it) has been a feature of system design methods since the 1970s.

Indeed encapsulating a system behind an interface has always been a tenet of GST.

So, is the three-way classification a progressive history?

Look again at the three classes of system thinking approach on the top of this paper.

Notice that the reference dates run suspiciously neatly in sequence from class 1 through class 2 to class 3.

Is it meaningful or useful to regard class 3 as an evolution of class 2, and that as an evolution of class 1?


The notion that systems thinking approaches can be classified in a linear history starting in 1956 is questionable.

Partly because there were already so many systems thinkers, with differing views, to draw from.

Read this paper for a list of systems thinkers starting in the 19th century.

Read Marxism and System Theory for discussion of how Marxist dialectic materialism appears in the system theory today.


Gerald Midgley (2000) presented three classes of systems thinking approach as an evolutionary sequence.

He wrote of three phases of inquiry, each relating to a particular focus of the systems field which brought with it a new set of methods.

·         Hard systems thinking: focused on concrete issues of ‘problems’ and problem solutions for issues where there was perceived “unity of purpose”.

·         Soft systems thinking: began with the wider soft systems perspective on people and their perspective on issues.

·         Critical systems thinking: is presented as the latest development in a historical progression.


You might reasonably view the history of system thinking instances as running in the opposite direction!

Social systems thinking (SST) – in both hard and soft flavours - emerged towards the end of the 19th century

General systems theory (GST) emerged in the middle of the 20th century.

It isn’t obvious that critical systems thinking brings many new methods, essential to the task, that could not be seen in earlier approaches.

I stand to be corrected on that.


Naturally, gurus present their preferred approach as the latest development in a historical progression.

And some modern-day consultants refer to their preferred approach as systems thinking.

That doesn’t mean their approach represents a historical evolution of GST, or applies its core ideas.

Read Marxism and System Theory for a challenges to the notion of inexorable progression.


This paper proposes there is a schism in management science, but the classification into hard, soft and critical obscures it.

The real schism

Remember second order cybernetics is radically different classical cybernetics.

It shifts attention from behaviors to their purposes (aka goals, objectives, targets).

And from abstract roles to individual actors, who each have their own purposes.


The table below contrasts two management styles which correspond to this schism in cybernetics.



Process-oriented management

Target-oriented management

Processes are

Behaviors are

People are given



tightly constrained

processes to follow

call centre people given scripts


loosely constrained

targets only

door-to-door sales people given targets


GST and classical cybernetics

Second order cybernetics.


Hard and soft systems thinking approaches usually involve modelling roles and processes.

And intervening to change some of those roles and processes.


By contrast, in an extreme version of target-oriented management, you ask a group of people to meet some goals by doing whatever they choose.

You rely on the individuals’ abilities to interpret your direction and choose behaviors that lead to the goals you set.

If the nature and nurture-given abilities of the actors are up to it, they may succeed better than you expected.


Most people management involves something of both process and target-oriented approaches..

The question here is not which is better or worse, more or less advanced, it is whether it target-oriented management is well-called “systems thinking”.

There is a social entity, but is there a social system?


In GST terms, a group of actors only form a system where, when and in so far as they agree some roles and rules and follow them for a while.

If the actors do agree some roles and rules, the system they describe is probably a simple one.

Whatever else they do – that is ad hoc, irregular, unrepeated, disorderly - is not systematic or part of that system.


Every enterprise employs actors who interact, directly or indirectly.

The enterprise may well be called a social entity, but is it also a “system”?

The answer depends on what kind of systems thinker you are.


System thinking or situation thinking?

System thinking can be seen as a kit bag of ideas and techniques for “situation thinking”.

It may lead to the description, testing and implementation of a new of changed system, or it might not.


From the 1970s onwards, systems thinkers have claimed institutions are in crisis, and something must be done.

Surely, institutions will always have problems, and system thinking will never provide a final answer to those problems.

It will always be necessary to intervene now and then.

Where an intervention involves describing regular behaviors, realizing them and testing the outcomes, it is an application of GST.

But consultants may make interventions of others kinds – with little or nothing by way of process definition or testing of outcomes.

It isn’t always clear that the situation addressed is a “system” in any sense beyond being a named entity - a named organization or named group of actors.


If every problem or situation is called a “system”, then the word system tells us little or nothing.

In GST terms, a problem/situation might be a system, or it might not; the solution might be a system, or it might not.


The schism

Some modern system thinking is about defining purposes, goals or targets and motivating people.

You may assemble some people and motivate them to work towards given goals, paying little or no attention to how they do the work.

That group is a certainly a social entity, and perhaps a successful one, but it is not a system in the sense Ashby would recognise.


The fact is: the “system” in second-order cybernetics is radically different from the “system” in classical cybernetics.

There is a schismatic distinction between.

·         A social system - in which actors realise roles and rules - describable in accord with GST and classical cybernetics.

·         A social entity - in which actors choose their own behaviors to reach agreed goals - as in second order cybernetics.


In GST and classical cybernetics, a system is describable as a set of roles, rules and regular behaviors.

If you change the roles and rules, then you change any concrete system that realises that system description.


In second order cybernetics, a system is a social entity - a named entity or organization – in which actors are engaged.

The actors may change the roles and rules of the entity they are engaged in (perhaps even change its aims).

As long the system name remains the same, people speak of it as same system, though its roles, rules and behaviors may be very different.


Social entity thinking tends departs from general system theory in one or more of the ways listed below.

General system theory

Not general system theory



General to all domains of knowledge

Specific to situations in which humans interact

About roles, rules and regular behaviors

About individual actors (purposeful people)

About systems at the base level of interest

About meta systems that define and change roles and rules

About describing testable systems

About solving any problem in any consensual way


Promoting a “participative democracy”


These differences are further explored in related papers at

The suggestion here is that social systems thinkers and enterprise architects can benefit from gaining a deeper understanding of general system theory, and respecting it more than they do.

System theory is good to know, good for the soul, and practically useful in all kinds of thinking about systems.


Of course, seeing a business as a social entity is important; and is a primary responsibility of business managers.

Management consultants continually generate approaches to identifying problems in social entities and solving them.

The question here is whether classifying all these approaches as varieties of "systems thinking” has a useful meaning.

If every problem or situation is a system, if every entity we name or point to is a system, then the term “system” is meaningless.


This table maps the 3-way system thinking classification we started with to the 2-way schism discussed in this paper

3-way classification


4-way classification

2-way classification

Class 1 hard systems thinking

Systems in which actors perform regular behaviors

General Systems Thinking

General System Theory and

Classical cybernetics

Class 2 soft systems thinking

Systems in which human actors perform regular behaviors

Social System Thinking

Named organizations in which humans determine their behaviors

Social Entity Thinking

Second order cybernetics and

Management Consulting

Class 3 Critical system thinking

Problematic situations

Situation Thinking


On science and scientism

GST and classical cybernetics is scientific in so far as its deals with behaviors that are regular, or deterministic, or reproducible.

Actual (empirical) performances of behaviors can be tested for conformance to abstract (theoretical) descriptions of those behaviors.

As, for example, the actual orbits of planets are tested for conformance to astronomers’ descriptions of those orbits.

And the actual behaviors of US governments are tested for conformance to the description of those behaviors in the US constitution.

Social system

Abstract system description

US constitution

Concrete system realization

US government


Evidence-based medicine is scientific; a medicine man (or shaman) is scientistic.

Some social systems thinking ideas are scientistic, meaning there is little or no evidence to verify or falsify them.

It easy to find problems in human organizations, more difficult to propose viable changes, and more difficult again to make them.

And then sometimes even more difficult again to prove whether the change was for the better or not.


Enterprise as a system, or system of systems

Business systems can be seen as formalised social systems, in the sense of GST and classical cybernetics.

Enterprise architecture is about changing a designed system under change control, from one generation to the next.

Changing a designed system’s roles and rules is to produce a new system (even if the system’s name and the actors in it remain the same).


Enterprise architecture sees a large enterprise as many distinct systems.

These systems may be uncoordinated; they may overlap, duplicate, conflict and fail to share information.

The ultimate vision of enterprise architecture is to unscramble this mess of systems.

To coordinate, de-duplicate and integrate distinct systems into one system, without duplication or disintegrity.


Bridging the schism

It is possible to recast second order cybernetics in a way that maintains the integrity of the system concept.

To put it another way, GST can be extended to reconcile classical and second order cybernetics.

1.      First, consider system change as incremental (generation-by-generation) rather than continual

2.      Second, separate the meta system M from the system S

3.      Third, allow an actor to switch between roles as system thinkers in M and system actors in S.


A new system classification

Here is the latest of several system classifications I have toyed with.

I don’t mean to present this as a scale of complexity, or a progression of any kind.

System kind

Actors relationship to scripts


Strong or Involuntary

Actors/parts use no script


Solar system


Cuckoo Clock

Actors/parts rigidly follow scripts


Biological organism


Software system

Weak or Voluntary

Actors/parts interpret scripts


Orchestra, Church

Actors/parts script their own roles


Marriage, Small business


System granularity?

System structures/components and behaviors/processes are composable and decomposable.

There are shorter processes within components, and longer processes that connect components one way or another.

Cross-component processes are needed to maintain the integrity of a system.

These cross-component process may be realised by either orchestration of, or choreography between, components.


These general system design issues are currently debated under the heading of “microservices”.

A useful discussion of microservices has to address the level of granularity.

And explore the consequences of dividing what could be one coherent data structure.

For some discussion, try this paper.




For further appraisal of systems thinkers’ ideas, try the system theory page at

For more background on systems thinking try “Introducing Systems Approaches”



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