I write in mid-July, deep into yet another summer of our discontent. Wildfires that make their own weather, relentless heat waves, and murderous floods driven by “thousand-year” rain events abound. Under such conditions, it’s easy to wonder whether human civilization can survive our naive cleverness. Our relentless fecundity. When you get down to it, our sheer selfishness.
What a time to find out that the predictions of an early-1970s “doomsday book” have been tested yet again, and guess what? The disasters now besieging us are following its schedule—a schedule that in some scenarios ends with the collapse of our civilization.
Let’s put this into a half-century or so of perspective. That’s how long it’s been since two bestselling books thrust concerns about overpopulation and resource depletion into public awareness. The first was The Population Bomb (1968), by Paul R. Ehrlich and Anne Ehrlich (initially uncredited).1 It predicted ruinous food shortages in the 1970s and 1980s if growth in human numbers went uncurbed. As it happens, the Green Revolution came along instead—forestalling short-term disaster, yet setting the stage for today’s crises of monocultural agriculture, deadly fertilizer runoff, soil and groundwater depletion, and the like. (To say nothing about a global population nearing eight billion. Temporarily bailed out by Borlaug’s brilliance, we squandered our windfall, making as many humans as we could instead of so arranging things that a smaller number might live bountifully.) While the Ehrlichs got many of their near-term predictions wrong, their longer-term forecasts proved dismayingly reliable. Perhaps nothing rings truer than the book’s core insight: limitless growth on a finite planet is impossible.
The second of these mammoth bestsellers was The Limits to Growth (1972).2 Commissioned by the Club of Rome, a high-level independent think tank, it reflected research by seventeen investigators led by the husband-and-wife team of Donella H. Meadows and Dennis L. Meadows of MIT. The Limits to Growth (hereafter LTG) used a then–cutting edge computer model of the entire world economy to calculate what lay ahead if humanity did—or didn’t—take decisive action on population, resource use, and similar key parameters. The “business as usual” (BAU) scenario predicted that harsh “limits to growth” would be encountered circa 2072, triggering “sudden and uncontrollable decline in both population and industrial capacity.” Some growth limits would kick in earlier: industrial output in 2008, food in 2020, and population in 2030. Ultimately, the BAU model projected broad-based societal collapse around the middle of this century.
Like The Population Bomb, LTG was another runaway bestseller. It triggered years of fevered discussion. Critics such as Cato Institute Fellow Julian Simon chided that the definition of a resource shifted as technologies evolve and that the innovation required to surmount looming crises could only be unleashed by continued growth.3 Numerous critics derided LTG’s World3 computer model, which though state-of-the-art in its time was ludicrously simplistic compared to later world-modeling constructs.
Yet forty-nine years later, LTG has not gone away. Its proponents still hold occasional conferences and issue retrospectives. Their core position is much like that of the Ehrlichs: Yes, we got a lot of details wrong, but our broader forecasts remain appallingly relevant.
Are LTG’s more disturbing predictions coming true? Consider its forecast (under one of its BAU scenarios) of a peak in industrial production in 2008. Who doesn’t remember 2008? The year rang in amid economic euphoria. Red-hot worldwide demand had fed spikes in the prices of numerous commodities, food riots in the developing world, and in America the rifling of unguarded buildings for suddenly precious copper wire and piping. Before the year sputtered out, a worldwide economic meltdown had put paid to euphoria. On many indices, we’re still not back to early-2008 levels of production and consumption (obviously, the COVID-19 pandemic hasn’t helped).4
Enter Gaya Herrington, now a risk manager at KPMG, one of the world’s four dominant accounting and consulting firms. In her 2020 Harvard master’s thesis, Herrington looked back to LTG, then reproduced some of its analyses using current data and modeling software.5 Her key finding: On variables such as population, fertility, human mortality, industrial output, food production, services, nonrenewable resources, pollution, general human welfare, and humanity’s ecological footprint, real-world events are closely following two pessimistic scenarios from the original LTG: “BAU2,” a business-as-usual scenario that assumed meaningful change would not be forthcoming; and “CT,” a comprehensive-technology scenario that assumed maximal tech growth would be pursued to the exclusion of other considerations.6
Are you an optimist? Then hope the CT scenario is correct. It predicts only a sharp decline in resource availability and a temporary drop in food production in the mid-2100s. If the BAU2 scenario is right, we face an out-and-out societal collapse circa 2040.
More optimistic scenarios exist, but radical changes in the way society manages itself would be required to divert us into those more benign trajectories. You know, the kind of changes we haven’t made on population since the 1950s, on many forms of pollution since the 1970s, and on carbon since the 1990s. (Note the new Intergovernmental Panel on Climate Change [IPCC] report, released as this issue was in production, confirming that humanity can no longer hope to avoid at least 1.5 degrees Celsius of global warming.)
Nor is Herrington’s study the first to look back on LTG using contemporary methodologies only to discover that the 1970s doomsday prophets were way less wrong than everyone thought. A 2014 University of Melbourne study found that trends in resource availability, in particular, “support the Limits to Growth modelling of resource constraints underlying [the prediction of an imminent] collapse.”7 Nor is this paper the only one that’s found much of worth in LTG’s thesis—if not in all the details of its prognostications.
The message in all this, of course, is the same message we should be hearing in news accounts of an environment run wild. We can hear it too in human numbers’ relentless sprint toward eight billion even though fifty-three years have passed since The Population Bomb sounded its unheeded warnings. Meanwhile, fifteen years have passed since Al Gore’s book and film An Inconvenient Truth burned awareness of the carbon crisis into the popular consciousness, and how little good has come of that?
Herrington’s paper is just one more indicator—among myriads—of how firmly humanity has its metaphorical foot on the nested banana peels of overpopulation, overconsumption, and environmental rapine. Secular humanism has always leaned toward the optimistic view that when crisis looms, humanity’s best can come to the fore as we find ways to solve our problems together.
To say the least, if that is going to happen—if it’s not already far, far too late to matter—we should have started long ago.
[1] Paul R. Ehrlich, The Population Bomb (Oakland, Calif.: Sierra Club, 1968).
[2] Donella H. Meadows, Dennis L. Meadows, et al., The Limits to Growth (New York: Universe Books, 1972).
[3] Julian L. Simon, The Ultimate Resource (Princeton, N.J.: Princeton University Press, 1981).
[4] I have reviewed in these pages two self-published books by Christopher Clugston, Scarcity (2012) and Blip (2019), which comprehensively explore the unsustainability of nonrenewable natural resources (NNR), a closely related issue.
[5] G. Herrington. “Update to Limits to Growth: Comparing the World3 Model with Empirical Data.” Journal of Industrial Ecology. 2020; 1–13. https://doi.org/10.1111/jiec.13084. The paper is also available online at https://advisory.kpmg.us/articles/2021/limits-to-growth.html.
[6] See Nafeez Ahmed, “MIT Predicted in 1972 That Society Will Collapse This Century. New Research Shows We’re on Schedule,” Vice, July 14, 2021; and “End Ahead” by A. J. Dellinger, Mic.com, July 14, 2021.
[7] Graham Turner, “Is Global Collapse Imminent?” MSSI Research Paper No. 4, Melbourne Sustainable Society Institute, The University of Melbourne. https://sustainable.unimelb.edu.au/__data/assets/pdf_file/0005/2763500/MSSI-ResearchPaper-4_Turner_2014.pdf.