On Thinking in Systems

Donella Meadows’s Thinking in Systems: A Primer, edited by Diana Wright, is a gem for anyone trying to make sense of complex systems. Early in her career Meadows worked with Jay Forrester on Limits to Growth, which remains an important point of discussion and was famous for its rigorous modeling of economic problems. Thinking in Systems was itself never meant for publication — it was drafted as a guide for other researchers working on system-wide problems — and after Meadows died young in 2001 it was edited and put into wider circulation. Its content is critical to making sense of life in the twenty-first century: there are no easy answers, and we can only find real solutions by looking at the systems surrounding a given issue.

The first chapter starts simply, with a definition. For Meadows, every system is made of three things: elements, interconnections, and a purpose. Take energy use as an infrastructural example — the “elements” are houses and power plants, the “interconnections” are the lines connecting them, and the “purpose” might be “the equitable use of energy” or “keeping people warm in winter,” two entirely different purposes that change the nature of the system. Elements and interconnections are further described by “stocks” (quantities of a thing) and “flows” (which move stocks around), and once there are multiple stocks and flows, systems change tremendously. Then there’s feedback, which may be automatic or manual. A cooling system is a feedback loop: it triggers the air conditioner to cool the house and shuts off when the thermostat reads 20°C. Simple enough — except that systems are never truly self-contained. The cooling system is always working against the outside temperature, which makes for two feedback loops, and the outdoor temperature is itself tied to larger climatic cycles. In reality everything is interconnected, so you can’t hermetically seal a system; but for the sake of measurement and analysis, Meadows argues, we have to draw our own boundaries, and where we draw them determines the quality and meaning of the analysis — they don’t have to be perfect, only good enough for whatever we set out to do. Because of all their parts, systems behave unintuitively, and what we find may surprise us, which it helps to accept without too much resistance. That’s why systems thinking matters: the answers it yields won’t come any other way, and only by examining the parts in relation to the whole can we understand economies, societies, infrastructure, and most of the sciences. The book is pitched at an introductory level — for the experienced it’s a good refresher with little new, but for anyone unaccustomed to thinking in systems it’ll be a welcome addition to the shelf.