Published in 1972, and shrouded in controversy since that date, ‘The Limits to Growth’ is the most successful econometric projection ever made.
The idea of these of blog posts is to introduce people to some ‘historic’ books and reports, which I think should be more widely read. To start, I thought I’d pick a book that for years has been vilified or deliberately ignored. Any discussion of its content is shrouded in controversy.
It’s the 1972 book, ‘The Limits to Growth’. My version is a second revised edition from 1974. Its 200 pages are a little more beaten-up than when I bought it second hand, as I refer to it quite a bit in debates.
Paul Ehrlich’s, ‘The Population Bomb’, had launched a debate about humans and the environment. Problem was, that book is based on pretty poor data. To resolve that lack of evidence, a group of scientists decided to create a properly researched model to look at humanity’s effect on their finite environment.
At this time ‘systems science’, computer models, and computer-based projection, were a very new thing – relatively little understood by politicians and the public. This new application of mathematics had arisen out of Cold War strategic planning. Applying it to global ecological issues was, though, a revolutionary idea.
The group outlined its work on page 27:
The model we have constructed is, like every other model, imperfect, oversimplified, and unfinished. We are well aware of its shortcomings, but we believe that it is the most useful model now available for dealing with problems…
As the book goes to great length to explain, rather than linear projection, the model incorporated feedback loops. This means that on each iteration of the model, the change in values depends upon the recent, not the initial conditions. A functional diagram of the model is shown on pages 110 and 111.
The basic issue here is that exponential growth – which is the basis of the human economy – isn’t linear. As humans we’re used to time, pounding away at a constant rate. Exponential growth increases with time: If a quantity grows a 2% per year, it will double every 35 years; increase that to 5% per year, and it will double every 14 years.
Those involved in the research – Donella and Dennis Meadows, Jørgen Randers, and William Berens – could not have possibly anticipated the nastiness of the response to their work. In many ways it prefigured the response to the climate change debate a decade later. The report sent right-wing lobbyists into apoplexy, and was attacked until the arrival of ‘Agenda 21’ twenty years later – which gave them a new target to vilify.
Figure 35: ‘The Standard Run’ Scenario
Though the book shows various options for future growth I’m going to focus on the ‘standard run’, shown in figure 35. The ‘standard run’ predicted that, in the middle of the first half of the Twenty-First Century, human activity would reach a peak and then decline. These results were called “Malthusian” at the time – a label that is often used today.
It was dismissed by the economic lobby. They had come to believe that growth was inexhaustible, and would continue forever. This is a modern, ideological reversal of the situation foreseen by the founders of modern economics – Adam Smith and John Stuart Mill – who believed that one day growth would end. As the book comments, Mill foresaw a steady state arising when everyone had as much as they could buy; Smith foresaw a slow decline as resources were exhausted.
‘The Standard Run’ illustration from Smithsonian Magazine
The reason why the book is so significant is that, after fifty years, it is the most successful econometric projection ever made. Recent research, using the latest data, have shown the results of the ‘standard run’ to be incredibly accurate.
One recent study commented that,
“Empirical data showed a relatively close fit for most of the variables.”
Another that, “As shown, the observed historical data for 1970-2000 most closely match the simulated results of the ‘standard run’ for almost all the outputs reported; this scenario results in global collapse before the middle of this century.”
The implications of the model are summed up on page 198 of the book:
“We firmly believe that the warnings this book contains are amply justified, and that the aims and actions of our present civilization can only aggravate the problems of tomorrow.”
More significantly, in framing their conclusions, they pre-dated the ‘decolonialism’ debate today. As they say in point 9 on page 198:
“We unequivocally support the contention that a brake imposed on world demographic and economic growth spirals must not lead to a freezing of the status quo of economic development of the world’s nations. If such a proposal were advanced by the rich nations, it would be taken as a final act of neocolonialism.”
The battered cover of my copy of ‘Limits to Growth’
Following the 1972 edition, various updates were published by members of the group. If you want to revisit the text, while the original is truly astounding in its foresight, these later versions are easier to get hold of.
Next year is fiftieth anniversary of ‘The Limits to Growth’. Once again, figures in the media, assuming they decide to cover it at all, will likely do so dismissively. The most curious fact is that the mainstream environmental movement dare not even talk about it in public. Some even try to close down such discussions because they are perceived as ‘negative’.
‘The Limits to Growth’ is an example of the human capacity to measure and project ecological impacts. More importantly, the response to it demonstrates the human capacity to ignore bad news by telling ‘noble lies’ – to the public, but most importantly, to ourselves.
Currently all evidence indicates the prognosis of ‘The Limits to Growth’ is still unwinding as predicted. Evidently our society is unable to deal with that because it has become addicted to growth and material affluence. And like any addict, they will dismiss any message which contradicts that lifestyle.