The Limits to Growth

The 1972 Club of Rome report by Meadows, Meadows, Randers and Behrens that used the World3 system-dynamics model to ask whether exponential growth in population and industry could continue on a finite planet.

A team at MIT built World3, a system-dynamics model in which population, industrial output, food, non-renewable resources and pollution act on one another through feedback loops, and ran it under a range of assumptions. The report presented the runs for a general reader: in most of them growth continues past the planet's limits and is followed by collapse within a century, while a stable equilibrium is reachable only with deliberate changes. It was commissioned by the Club of Rome, sold in the millions in many languages, and set off an argument that has not finished. The authors revisited the model in 1992 and again in a 30-year update in 2004.

For a twin builder it is the best known case of a whole-system model shaping public debate, and a case study in everything that follows from that: how results get read as predictions, how a model's limits get lost in transmission, and how much a small, clearly documented model can carry.