Preface to part three at

A new look at systems thinking


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Much written under the heading of “systems thinking” obscures what is interesting and valuable in both social entity thinking and in activity system thinking, and this book attempts to clarify. Two needs must be addressed.

The need of EA for a proper foundation   

"The Information Age" is the name given to the shift, starting in the 1960s, from industries established by the Industrial Revolution to an economy enabled and supported by the exchange of digital messages, and storing of memories, using information technology. This “digital transformation” continues today.


The term "Enterprise Architecture" (EA) was coined in the 1980s in relation to the impact of this shift on business activity systems that create and use business data. It has been said that EA regards an enterprise as a "system of systems". So, you might assume enterprise, business and software architects are taught system theory. With rare exceptions, you’d be mistaken. This book presents the theory that underpins what they do, whether they know it or not.

The need for a model of the system of interest

“All scientific constructs are models representing certain aspects or perspectives of reality.” Bertalanffy 1968


If business architects are to observe a system, or envisage changes to it, they need a model of it they can manipulate in their “mind’s eye”.  Much written in this book relates in one way or another to ideas everybody should be familiar with.


·       An open system receives inputs and produces outputs.

·       A brain or business holds a model of things it must monitor (from inputs) and direct (by outputs).

·       Two models made of one reality may represent compatible, conflicting or competing viewpoints.


What is light? Is it waves or particles? We can never understand reality, we can only understand descriptions (views or models) we have of reality. That is a basis of modern science.


Every substantial entity or situation is infinitely complex in reality. Our attention being limited, we can only understand those elements we select for attention. Holism is considering how effects or results emerge from the interactions between those things. Wholeism is impossible.


Moreover, different observers may abstract different models from the same reality. Different observers may identify different systems in the same business, in the light of the different goals or interests they bring to it. So, it is meaningless for people to refer to a social of business entity (say IBM) as a system with no reference to a model of it. We can’t discuss the system they are thinking of until they reveal their model of it. Only then can we explore, verify and use that model to meet our aims.


No EA or BA model can represent more than a fraction of the reality that is a whole enterprise. However, we don’t need a model that is complete and perfect. We need a model, of features relevant our aims, that is complete and accurate enough to help us understand what is modelled, and make some purposeful change to it.

This part

Look at any business, and you will see actors performing activities to meet some agreed aims. To a greater or lesser extent, the actors are organized and the activities are systemized. This raises a question that has hung over social system discussions since the nineteenth century. At the centre of our thinking, do we put the actors or the activities? As David Seidl has said "The first decision is what to treat as the basic elements of the social system. The sociological tradition suggests two alternatives: either persons or actions."


My education (in psychology, biology and the philosophy of science) leads me to start from the position that a government institution, or a university, is not a system. Rather, it is a social entity (in which the basic elements are actors) that employs and participates in several human activity systems (in which the basic elements are actions).


Abstracting activity systems from the entities that realize them is what Ashby and Forrester (also “soft systems” gurus like Ackoff and Checkland) urged us to do when modelling a real-world human activity system. It is, any case, what every enterprise, business and software architect does. This part reviews what every systems thinker should know, it shows how distinguishing activity systems from social entities leads to a more consistent and coherent view of the whole systems thinking field. It divides systems thinking into two broad schools. It distinguishes agile systems from agile system development. It discusses “self-organization” and a way of approaching “wicked problems”.


Part three defines the core terms and concepts of business architecture in EA, in the context of a process for designing business activity systems. However, it is not so much a “how to” method as an exploration and explanation of where systems thinking ideas are best used in and alongside any framework or method you already know, such as TOGAF or BIZBOK.