Further Reading is going to be a series of posts on books, resources, and articles on topics that relate to and/or impact the Interlock. As I mentioned in the last post, while systems theory underlies the Interlock, this website isn’t really the proper place to go into a detailed discussion of it, and other people have done it better than I could hope to. So, for the inaugural post in the Further Reading series, we’re going to be going on a whirlwind book tour:
Draper Kauffman – Systems 1: An Introduction to Systems Thinking
Like a lot of people who have studied systems, my first exposure to the fundamental ideas came from this slim booklet. Systems 1 is a 64-page primer on how systems and feedback works, written in clear, simple language with familiar examples. Draper Kauffman (who is, full disclosure, the Assistant Director of the Interlock Project and my father) was one of the pioneers in the systems field, and this little book has been used to introduce systems to a wide range of audiences, from gifted middle schoolers to executives and Pentagon officials. Its prose is very approachable, and it’s a quick read (although fully digesting the implications might take a while). The book has some dated content, but if you want a completely non-technical introduction to systems thinking, then this is probably the best place to start. (There was also a companion, Systems 2: Environmental Systems, but it is out of date and no longer generally available.)
Donella Meadows – Thinking in Systems: A Primer
Donella Meadows was another pioneer in the field, and this book is a college-level equivalent of Systems 1 & 2 – a basic introduction to systems, with discussion of case studies and examples of systems, modeling, and how to use systems thinking to help yourself or your organization deal with the systems around you.
Virginia Anderson & Lauren Johnson – Systems Thinking Basics
Often used as a companion to either Systems 1 or Thinking in Systems (or both), this is a workbook that takes students step-by-step through learning how to use and communicate systems ideas. Not strictly necessary for a self-taught course in systems, but still useful.
Peter Senge – The Fifth Discipline
In this book, Senge presents a more application-focused perspective on systems thinking. The Fifth Discipline is concerned with applying systems thinking to organizations to improve the way they (and the people within them) function. The parts dedicated to systems are couched as an introduction for those unfamiliar with the subject, but the book as a whole presents an application of systems thinking that every student of systems should become familiar with.
Robert Axelrod & Michael D. Cohen – Harnessing Complexity
Axelrod & Cohen couch their book in a way to make it appealing to a leadership audience, but this book is as much a theoretical tour-de-force as it is a leadership or management guide. The content is focused on the emergent properties of complex systems, and how to think about and model the agents within those systems. There’s a fair amount of game theory involved, as well, which adds a very interesting new twist on thinking about systems that depend on cooperation. This is not light reading, despite the short length of the book – the writing is dense, and the concepts are deep and complex, but nonetheless it’s definitely worth reading.
Advanced Study: Systems Modeling
For those interested in going to the level beyond systems thinking and learning how to craft working models of systems, there are two main approaches to doing so. The first is based on what are often called “stock and flow diagrams,” using an approach usually called systems dynamics (SD) that was developed by Jay Forrester at MIT in the 60s and 70s. (I’ll discuss the second approach in the next Further Reading.)
Although capable of sophisticated and complex modeling, SD is, at its core, based on a simple plumbing metaphor. The “stocks” are the things in the system that can fill up or be depleted. The “flows” determine how fast the stocks are filled or emptied. Flows are controlled by “valves” (formulas) that depend, often in complex ways, on other flows and on the levels of various stocks in the system.
Think of a standard flush toilet tank with a float valve. When an outside stimulus disturbs the system (i.e., someone presses the handle), the bottom valve opens and lets the water rush out, depleting the stock of water in the tank. When the level of the stock (the water) is low enough, the flush valve at the bottom of the tank closes, shutting off the flow of water out of the tank. Meanwhile, the dropping water level causes the float to go down, which opens the inlet valve, allowing more water to enter the tank. As the tank fills, the rising water lifts the float, which closes the inlet valve again, restoring the system to its original state.
As simple and familiar as that model is, the ideas behind it can be applied to a wide variety of complex systems, ranging from population dynamics and epidemiology to many businesses and other organizations that handle varying inputs and outputs, such as orders, inventories, and cash. It’s even surprisingly effective for modeling psychological states, such as love, fatigue, or anger. In general, if you can use words like “level,” “amount,” “size,” “increase,” “decrease,” and “rate” to describe the key elements in a system – e.g., my level of frustration is increasing rapidly or the sales of that product decreased at an annual rate of 15% – then SD is likely to be the best tool for modeling it.
Whether you’re in business or not, this book by MIT systems professor John Sterman is a mandatory read for dedicated students of systems dynamics, one of the two main approaches to modeling complex systems. While it does cover the usual introductory material on systems thinking, it quickly dispenses with holding the reader’s hand and dives right into systems modeling. It covers a wide variety of systems that might be modeled, and has a series of case studies with accompanying models to demonstrate the applications that SD models can be put to.
Business Dynamics is the definitive textbook on systems theory and SD-based modeling and their practical uses in the real world. If you want to go beyond just familiarity with concepts to actual being able to build models of complex systems, you need it. Unfortunately, it’s also priced like a textbook, so it might be a good idea to find it in a library, buy it used, or search for the paperback edition (often available as an import for around $30-$40), rather than spending more than $200 for a new hardback. If you get it used, be sure it still has the CD-ROM.
(See also John Sterman’s own page for this book, with a detailed table of contents.)
That should be enough (more than enough, really) to get you started, but it doesn’t end there – systems are all around us, and there are many more books that are worth checking out if this subject has piqued your interest.