Systems are everywhere. You wouldn’t be reading this without networks of interlocking systems to enable it, from the cell to the eye to the computer to society. Some systems are simple enough, and some involve many “moving parts” at many levels with complex networks of feedback and control.

In the first chapter of this book, the author says that he is convinced that “intelligence depends on the ability to construct coherent and sensible models.” Many times, these models are unstated and unexamined, but better understanding of the models usually depends on stating them and describing them in as much detail as we can manage.

This book is a kind of catalog of models of systems, each with increasing complexity. These can be simple models in (for instance) population dynamics, with easily written mathematical descriptions and only a few variables--easily described, easily simulated, and usually easily understood. (Chaotic dynamics is only briefly mentioned, late in the book.) By the end of the book, the models are very complex indeed, with multiple levels of feedback, complex dynamics, and both sub- and super-systems providing inputs.

There are ten chapters. Each has some general material, as well as complementary material with specific examples. Chapter 1, “The Language of Systems Thinking for Control Systems,” gives a basic outline of the goals of the book and an overview of some simple systems and how we describe them. Chapter 2, “The Ring: The General Structure of Control Systems,” covers the notion of modeling a system as a ring with feedback and control. The next chapter, “The Ring Variety: A Basic Typology,” covers several different types of control systems with “single lever” controls. Chapter 4, “The Ring Completed: Multi-lever and Multi-objective Control Systems,” begins coverage of multi-lever and multi-objective systems. “The Ring: Observation and Design,” chapter 5, considers how to look at systems and identify components and how they interact, as well as some of the problems in doing so. The next four chapters investigate varying levels of complex systems: “The Magic Ring in Action: Individuals” (chapter 6); “The Magic Ring in Action: Life Environments” (chapter 7); “The Magic Ring in Action: Organizations” (chapter 8); “The Magic Ring Explores Cognition and Learning” (chapter 9); and “Concluding Remarks: Toward a General Discipline of Control” (chapter 10).

There are a number of useful and informative diagrams of system structure. However, as more are presented, many start to look rather the same.

There are also a few plots of system behavior as modeled by a computer, sometimes with tabular data included. The tabular data is not very helpful, but the plots will be useful to those used to reading such plots and to systems simulation. The preface mentions that Excel spreadsheets and Powersim models may be available, but quick searches online failed to find these.

Overall, this book is a fairly good read with lots of interesting examples and some thoughtful commentary along the way. As a book intended for general readership (which is a stated goal), it is less convincing. Non-mathematical readers will find the relatively small amount of mathematics off-putting; mathematical readers may want better mathematical descriptions of the systems; and others are likely to want models to play with.

The lack of models to experiment with is particularly striking because the author opens with the notion that building models is essential. The best way to get an understanding, however superficial, of complex models depends strongly on having a good understanding of simpler ones.