Limits to Growth

Club of Rome Limits to Growth (1972)


In the summer of 1970, Professor Jay Forrester of MIT presented a global computer model to the Club of Rome conference in Cambridge, Massachusetts. This global model enabled the analysis of the behaviour and dynamic relationships of over 100 factors including population, agricultural production, natural resources, industrial production, and pollution.


An international team under the direction of Professor Dennis Meadows was set up to examine five basic factors that determine and ultimately limit growth on our planet. Many different model runs were made based on different inputs of the physical aspects of humankind’s behaviour. In all model runs capital and population growth were allowed to continue until they reached some natural limits.


The results of the study were published in the book The Limits to Growth (1972).  When population and capital growth were allowed to grow without human constraints, there was no policy that avoided the scenario of an exponential growth of population and capital followed by collapse. Some policies delayed collapse, but a collapse scenario by the year 2100 and earlier were common to all model runs without human constraint as shown in Figure 1.

Figure 1: Limits to Growth Collapse Scenario adapted after Meadow et al. 1972

There are limits to growth because the Earth is finite.


Exponential growth on a finite planet will inevitably stop either voluntarily or due to mounting global pressures.


The sooner we act to slow down exponential growth and stop growth in population and material consumption, the more possibilities will be available for future generations.

In the process of seeking the requirements for global equilibrium, constraints on population and capital growth were each tested separately. It was found that the collapse scenario also applied for these conditions. Global equilibrium was achieved when simultaneous constraints on population and capital growth were tested.


The Limits to Growth (1972) made the following four points:






The minimum requirements for global equilibrium, or steady state, were defined as being:





The above minimum requirements for steady state in a human ecosystem are equivalent to the conditions for climax in other ecosystems.

Critique of The Limits to Growth (1973)


In 1973, a year after The Limits to Growth was published, thirteen essayists associated with the Science Policy Research Unit of the University of Sussex published the book Thinking about the Future: A Critique of The Limits to Growth. This book represented a severe criticism levelled against the findings of The Limits to Growth. The team was co-ordinated by Marie Jahoda, Professor of Social Psychology at the University of Sussex. The main criticisms of the Sussex team were as follows:





The general nature of criticism was on points of methodology which the Limits to Growth team itself had pointed out. Some criticisms were on points of accuracy. The general conclusion of the Sussex team was that forecasts of the world's future are very sensitive to a few key assumptions and the Sussex team suggested that the assumptions made by the Limits to Growth team might be unduly pessimistic. The Sussex team concluded:


"The major weakness of the world dynamics models is that they illustrate the pessimistic consequences of exponential growth in a finite world without taking account of politics, social structure, and human needs and wants. The introduction of an extra variable – man - into thinking about the world and its future may entirely change the structure of the debate which these models have so far limited to physical properties." (Cole et al., 1973)


The Limits to Growth (1972) was interpreted by some critics as being a prediction of gloom. This is incorrect. The Limits to Growth (1972) was not about a preordained future, but instead was about choice. The Limits to Growth (1972) raised questions such as:





The Limits to Growth (1972) certainly contained a warning, but also a message of promise and hope.


The main finding of The Limits to Growth 1972 - that unless population and capital growth are constrained, further growth would eventually lead to collapse – had not been successfully challenged.


In the words of Kenneth Boulding, “Anyone who believes that exponential growth can go on forever in a finite world is either a madman or an economist."

Humankind at the Turning Point 1976


1976 heralded in the publication of the second report to The Club of Rome - Humankind at the Turning Point. Mihajlo Mesarovic and Edward Pestel headed the research team which also used a world dynamics model with the following major structural characteristics:





The computer model used about 100,000 relationships as compared to a few hundred in other world models. The following conclusions were made:


"A world consciousness must be developed through which every individual realises his role as a member of the world community.


A new ethic in the use of material resources must be developed which will result in a style of life compatible with the oncoming age of scarcity. This will require a new technology of production based on minimal use of resources and longevity of products rather than production processes based on maximal throughput.

An attitude toward nature must be developed based on harmony rather than conquest.


If the human species is to survive, humankind must develop a sense of identification with future generations, and be ready to trade benefits to the next generations for the benefits to himself. If each generation aims at maximum good for itself, Homo Sapiens is as good as doomed." (Mesarovic & Pestel, 1976)

The second report to The Club of Rome - Humankind at the Turning Point – confirmed the basic findings of The Limits to Growth (1972).

Limits to Growth Revisited (1992 & 2004)


The Limits to Growth (1972) was updated in 1992 with a further update in 2004.


In 1991 the Club of Rome team had a re-look at prevailing environmental data and realised that despite the world's improved technologies, humanity had already overshot the limits of Earth’s support capacity. Research independent of that of the Club of Rome and quoted in the Club of Rome’s 1992 edition indicated that resource and pollution flows had grown beyond their sustainable limits. Pollutants affecting the ozone layer was a prime example. There was also growing evidence that the rain forests were being cut at unsustainable rates, speculation that grain production could no longer keep up with population growth, and research had gathered evidence of a trend that the global climate was warming. The conclusions of The Limits to Growth (1972) report were accordingly strengthened in the 1992 edition Beyond the Limits: Global Collapse or a Sustainable Future referred to here onwards as The Limits to Growth (1992). The conclusions are as follows:


“1. Human use of many essential resources and generation of many kinds of pollutants have already surpassed rates that are physically sustainable. Without significant reductions in material and energy flows, there will be in the coming decades an uncontrolled decline in per capita food output, energy use, and industrial production.


2. This decline is not inevitable. To avoid it two changes are necessary. The first is a comprehensive revision of policies and practices that perpetuate growth in material consumption and in population. The second is a rapid, drastic increase in the efficiency with which materials and energy are used.


3. A sustainable society is still technically and economically possible. It could be much more desirable than a society that tries to solve its problems by constant expansion. The transition to a sustainable society requires a careful balance between long-term and short-term goals and an emphasis on sufficiency, equity, and quality of life rather than on quantity of output. It requires more than productivity and more than technology; it also requires maturity, compassion, and wisdom.” (Meadows et al., 1992)


In anticipation of further claims of predictions of gloom, The Limits to Growth (1992) added the following clarification to the above conclusions:


“These conclusions constitute a conditional warning, not a dire prediction. They offer a living choice, not a death sentence. The choice isn’t necessarily a gloomy one. It does not mean that the poor must be frozen in their poverty or that the rich must become poor. It could actually mean achieving at last the goals that humanity has been pursuing in continuous attempts to maintain physical growth.” (Meadows et al., 1992)


In 2004 The Club of Rome published the 3rd edition of Limits to Growth (1972) with the title of Limits to Growth: The 30-Year Update referred to here onwards as The Limits to Growth (2004). The 3rd edition was published in order to “restate our 1972 argument in a way that is more understandable and better supported by all the data and examples that have emerged during the past decades”.


Environmental data subsequent to 1992 further supported The Limits to Growth (1992) message that humanity had already approached overshoot mode.  For example, Mathis Wackernagel et al. (1997) had measured the ecological impact of 52 large countries inhabited by 80% of the world population and compared it to Earth’s carrying capacity. The carrying capacity was expressed in terms of the land area that would be required to sustain humanity at its current level of population and material consumption while both absorbing carbon dioxide (CO2) emissions from the combustion of fossil fuels and preserving ecological systems and the eco-services that nature is able to regenerate.  Wackernagel et al. concluded that in 1992 the impact of population and material consumption, or humanity’s ecological footprint, exceeded the Earth’s carrying capacity by 20%. By 1997, the ecological footprint exceeded the Earth’s carrying capacity by 33%. Limits to Growth (2004) concluded:


“Consequently, we are much more pessimistic about the global future than we were in 1972. Humanity has largely squandered the past 30 years in futile debates and well-intentioned, but half-hearted, responses to the global ecological challenge.”


Notwithstanding that humanity is in overshoot mode, The Limits to Growth (2004) stressed that “resulting damage and suffering can be greatly reduced through wise policy”, and once again clarified that:


“We do not write this book in order to publish a forecast about what will actually happen in the twenty-first century. We are not predicting that a particular future will take place. We are simply presenting a range of alternative scenarios: literally, 10 different pictures of how the twenty-first century may evolve. We do this to encourage your learning, reflection, and personal choice”.


The three editions of The Limits to Growth reflect a changing understanding of climate change. The 1972 publication showed the C02 curve going up, but this curve was included primarily to illustrate an example of persistent pollution. Although it was known that CO2 emissions from the combustion of fossil fuels is a persistent pollutant which stays in the atmosphere for a long time and that a build-up of CO2 affects the local climate, there was limited understanding and concern about climate change in 1972. Although climate change has now become a major over-riding global environmental pressure, climate change is nonetheless but one of several symptoms caused by population growth and growth in material consumption.

Limits to Growth (1992) clarified that its conclusions constitute a conditional warning, not a dire prediction. They offered a living choice, not a death sentence.


Limits to Growth (2004) was much more pessimistic about the global future than in 1972.


Humanity had largely squandered the previous 30 years in futile debates and well-intentioned, but half-hearted, responses to the global ecological challenge.

Limits to Growth Revisited (2005 to Present)


Turner 2008


In 2008, Graham Turner focused on a comparison of recently collated historical data for 1970–2000 with scenarios presented in The Limits to Growth. His analysis showed that 30 years of historical data compared favourably with key features of a business-as-usual scenario called the ‘‘standard run’’ scenario, which results in collapse of the global system midway through the 21st century. The data did not compare well with other scenarios involving comprehensive use of technology or stabilizing behaviour and policies.


Bardi (2011


In his 134-page book The Limits to Growth Revisited (2011), Ugo Bardi wrote a comprehensive history and commentary of The Limits to Growth (1972). The following is a precis using a selection of Ugo Bardi’s own words:


Much of the criticism of “Limits to Growth” was based on a misunderstanding of the nature and purpose of systems dynamics models. Some critiques were based on cherry-picking of the data and some were outright mistaken readings of the tables. The original authors were careful to note that their quantitative results for the future were not predictions, but simply the logical outcomes of their model and assumed inputs, what have come to be known as “scenarios.” The results were “robust” over a wide range of assumptions about such things as proven mineral reserves and technological progress. The qualitative result was always the same - the world system was heading for serious trouble and only the scale of the trouble and its timing were in doubt.


The Limits to Growth study was conceived and implemented in the early 1970s when computers and analytic software were still relatively new. It is not surprising if one could not find some flaws. Nonetheless, The Limit to Growth (1972) pioneered a new way of thinking that is sorely needed in our study of current problems. All of us, including key decision makers, work with models about how the world works. But these models are often poor models, typically static and linear, with vague and untested assumptions. The Limits to Growth (1972) was open and specific about its assumptions, and the model was available for all to see, in contrast to those of many of its critics. It was, in short, a good scientific first step and it is our loss that it was not treated as such, especially by economists and demographers.


The study first received much positive acclaim, and then was trashed—notably by economists—and largely ignored. More recently there has been renewed interest and a more sympathetic hearing, as the study is seen to have continuing relevance to current environmental, demographic, economic, and political instabilities. The core message that was contained in The Limits to Growth (1972), and reinforced in two later versions, most recently in 2004, was that in a finite world, material consumption and pollution cannot continue to grow forever. What was considered as futuristic 40 years ago has now become the reality of today. We are already in “overshoot” in a number of fields, and it is becoming obvious to more and more people that we have entered into a dangerous era: global warming, peak oil, biodiversity extinction, and reduced ecosystem resilience to name a few.


Jackson & Webster (2016)


According Tim Jackson and Robin Webster (2016):


“There is unsettling evidence that society is still following the ‘standard run’ of the original study – in which overshoot leads to an eventual collapse of production and living standards. Detailed recent studies suggests that production of some key resources may only be decades away.


Certain other limits to growth – less visible in the 1972 report – present equally pressing challenges to modern society. We highlight, in particular, recent work on our proximity to ‘planetary boundaries’ and illustrate this through the challenge of meeting the Paris Agreement on climate change. We also explore the economic challenge of a ‘secular stagnation’.


If the Club of Rome is right, the next few decades are decisive. One of the most important lessons from the study is that early responses are absolutely vital as limits are approached. Faced with these challenges, there is also clearly a premium on creating political space for change and developing positive narratives of progress.”


Herrington (2021)


Gaya Herrington, a Dutch econometrician, was a Director of Sustainability Services for KPMG US when she published research in the Yale's Journal of Industrial Ecology comparing the World3 model created in the ‘70’s by MIT scientists with empirical data. According to Gaya Herrington:


“Given the unappealing prospect of collapse, I was curious to see which scenarios were aligning most closely with empirical data today. After all, the book that featured this world model was a bestseller in the 70s, and by now we’d have several decades of empirical data which would make a comparison meaningful. But to my surprise I could not find recent attempts for this. So I decided to do it myself.” (Herrington, 2020)


Gaya Herrington stated:


“In the 1972 bestseller Limits to Growth (LtG), the authors concluded that, if global society kept pursuing economic growth, it would experience a decline in food production, industrial output, and ultimately population, within this century. …This research constitutes a data update to LtG, by examining to what extent empirical data aligned with four LtG scenarios spanning a range of technological, resource, and societal assumptions. The research benefited from improved data availability since the previous updates and included a scenario and two variables that had not been part of previous comparisons. The two scenarios aligning most closely with observed data indicate a halt in welfare, food, and industrial production over the next decade or so, which puts into question the suitability of continuous economic growth as humanity’s goal in the twenty-first century.“ (Herrington, 2020)


Herrington 2022


Gaya Herrington next wrote the 210-page book Five Insights for Avoiding Global Collapse: What a 50-Year-Old Model of the World Taught Me About a Way Forward for Us Today (2022), Gaya Herrington states in her Introduction:


“In this book, I will describe how I came to the conclusion that we live in a moment of extraordinary historical relevance. What a unique now-or-never moment we have to turn around humanity’s current trajectory towards something much better than the society we live in today. And why failure to make this turnaround will result in a significantly worse one.” (Herrington, 2022)


Gaya Herrington concludes as follows:


… my research shows that empirical data today align closely with some of the LtG scenarios. This close alignment implies that growth will halt within the next few decades one way or another, and the only choice we have left is its cause: social and environmental breakpoints, or our own conscious action to limit the ecological footprint of how we meet everyone’s needs.


… The transformational changes that are required for realignment onto a path towards a sustainable world can only be made in time by working at the generative level of our collective narrative.


… Now that we have reached global power, we have a choice to keep using it for an empty delusion of domination or to direct our might towards genuine happiness. If global society does not make the shift in mindset from a domination model to a partnership one, humans will not cease to exist. But it would result in a lot of unnecessary suffering, including early death for some, as well as massive biodiversity loss and possible ecosystem breakdown. (Herrington, 2022)

Empirical data today align closely with some of the Limits to Growth (1972) scenarios.


This close alignment implies that growth will halt within the next few decades.


We need to limit our ecological footprint by reducing our excessive production and consumption.


Bardi, U. (2011) The Limits to growth Revisited. New York, Springer.

Herrington, G. (2020) Update to limits to growth: Comparing the world3 model with empirical data. Journal of Industrial Ecology 2021; 25: 614– 626

Herrington, G. (2022). Five Insights for Avoiding Global Collapse: What a 50-Year-Old Model of the World Taught Me About a Way Forward for Us Today. Basel: MDPI, Page Range.

Jackson, T., and R. Webster. (2016) Limits Revisited: A review of the limits to growth debate

Meadows, D.H., D.L Meadows, and J. Randers. (1992) Beyond the Limits: Global Collapse or a Sustainable Future. London, Earthscan Publications Ltd.

Meadows, D.H., D.L. Meadows, J. Randers, and W.W. Behrens. (1972) The Limits to Growth. London, Earth Island Ltd. 

Meadows, D.H., J. Randers, and D.L Meadows. (2004) Limits to Growth: The 30-Year Update. Earthscan Publications Limited.

Mesarovic, M. and E. Pestel. (1974) Mankind at the Turning Point: The Second report to the Club of Rome. New York, Signet Book.

Turner, G.M. (2008) A comparison of The Limits to Growth with 30 years of reality. Global Environmental Change 18 397-411.

Wackernagel et al.  (1997) Ecological Footprints of Nations: How much nature do they use? – How much nature do they have?