"The Limits to Growth" continues to make waves

The Club of Rome is holding its annual meeting in Cape Town, South Africa. In the image, you see the co-president, Sandrine Dixon-Decleve, speaking

Now heading toward its 50th anniversary, "The Limits to Growth," the 1972 study sponsored by the Club of Rome, continues to generate interest. Past is the time of the "Limits-Bashing" fashion, when no one would dream to cite the study except to say that it was wrong. But there are still plenty of people who blindly repeat the legend that the study had predicted shortages that never occurred. As Daniel Dennett said, we are apes infested with memes and the Limits to Growth is an especially virulent one. 

Here, Marc Cirigliano writes a balanced review of the story, citing my book on the subject and giving some credit to one of the main critics of the study, Julian Simon, who in my opinion would deserve some more bashing but I admit that he may have been, at least, well-intentioned. 


 

The Best People: Ignoring the American Need for Environmental Deliverance for Over 50 Years

By Marc A. Cirigliano

Popular journalism seems to have finally caught up with what the scientists have been telling us for well over five decades about the environment. You really can’t read anything in mainstream news or commentary without coming across articles about such ecological matters as overpopulation, pollution, resource use and climate change. The main topics related to these stresses include human excesses, noticeable changes that affect the day-to-day well-functioning of a society somewhere on the planet or the long-term viability of human life as we now know it.

It has not been an easy matter for science to get to the point where environmental problems are part of the grist of everyday reporting and opinion pieces. The opposition has been fierce, well funded and plays upon people’s primal fears.

Science discovers new ways of thinking about the world. Often, this is unsettling because with a new way of thinking, there comes change, and, with change, comes the possibility of loss. Sometimes the threat of loss may seem monumental, overwhelming, and, perhaps, even apocalyptic.

Change may portend personal dislocation, social change and economic upheaval. No wonder, then, that some people may see some aspects of scientific advancement as a threat. Further, people in authority may feel that a new scientific discovery threatens their very position of power within society.

One historic centuries old example is religion’s well-known and consistent opposition to a scientific explanation for the universe that upended the Christian one. Science told us the Earth was no longer the center of a God-designed universe. To threaten religion’s primacy even more, evolution upended the hexplanation that humans descended from Adam and Eve. In place of that, science said we descended from other life forms.

Religion freaked out even as the evidence mounted that science was correct.

Still today some clerics defend their authority over parishioners by still insisting the Bible is the undeniable authority in understanding the functioning of the universe, the origin of humans and the motive of humans in living on the planet. Some use it as a reason to oppose environmental reforms all together. Looking at the idea that informs the Abrahamic religions of Judaism, Christianity and Islam, Genesis 1:26 (NIV) gives use the dominion argument:

Then God said, “Let us make mankind in our image, in our likeness, so that they may rule over the fish in the sea and the birds in the sky, over the livestock and all the wild animals, and over all the creatures that move along the ground.”

Yes, the dominion argument is that God sanctioned humanity with using the earth as we see fit. Enironmental science puts forth a different view.We will come back to science as a threat to the authority of the status quo later.

A Major Environmental Warning from 1972


By the 1960s, science had established, or more precisely, environmental science had developed a proven explanation for the complex way ecosystem earth functioned. This explanation used the idea of population dynamics. Here, population growth, carrying capacity, overpopulation and population collapse—also referred to as a die-off or crash—were part of a pattern of life both in a segment of the environment or even on the planet as a whole. Bear in mind that as science developed its ideas on population dynamics, earth was in the midst of a population explosion never before seen.

In 1972, the Club of Rome received a report they had commissioned from four MIT researchers— Donella H. Meadows, Dennis L. Meadows, Jørgen Randers and William W. Behrens III—to study what they called the predicament of mankind. This team published The Limits to Growth (LTG), subtitled A Report for the Club of Rome’s Project on the Predicament of Mankind.

The researchers described their goal and the predicament they were proposing we fix:

The intent of the project is to examine the complex of problems troubling men of all nations: poverty in the midst of plenty; degradation of the environment; loss of faith in institutions; uncontrolled urban spread; insecurity of employment; alienation of youth; rejection of traditional values; and inflation and other monetary and economic disruptions. (10)

The LTG supplied a new way of looking at these problems, problems they labeled as the world problematique:

It is the predicament of mankind that man can perceive the problematique, yet, despite his considerable knowledge and skills, he does not understand the origins, significance, and interrelationships of its many components and thus is unable to devise effective responses. This failure occurs in large part because we continue to examine single items in the problematique without understanding that the whole is more than the sum of its parts, that change in one element means change in the others. (11)

In other words, each of these elements—poverty, environmental loss, social mistrust, overpopulation, job loss, alienated youth, etc.—is part of a system, with system defined as “a regularly interacting or interdependent group of items forming a unified whole.”

Consequently, instead of studying each of these problems separately from the system, the LTG proposed to study them as part of an environmental system. The way they examined this as a system was to develop a model, which they clarified as “simply an ordered set of assumptions about a complex system.” (20)

This was a new approach at that time in 1972.

Let us look at some of the specifics. TLG clarifies:

Our world model was built specifically to investigate five major trends of global concern-accelerating industrialization, rapid population growth, widespread malnutrition, depletion of nonrenewable resources, and a deteriorating environment. (21

The TLG draws a distinction between their approach and more traditional ones:

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 far out on the space-time graph. To our knowledge it is the only formal model in existence that is truly global in scope, that has a time horizon longer than thirty years, and that includes important variables such as population, food production, and pollution, not as independent entities, but as dynamically interacting elements, as they are in the real world. (21-22)

TLG gives us three observations on how we may address these problems:

The present growth trends in world population, industrialization, pollution, food production, and resource depletion continue unchanged, the limits to growth on this planet will be reached sometime within the next one hundred years. The most probable result will be a rather sudden and uncontrollable decline inf both population and industrial capacity.  t is possible to alter these growth trends and to establish a condition of ecological and economic stability that is sustainable far into the future. The state of global equilibrium could be designed so that the basic material needs of each person on earth are satisfied and each person has an equal opportunity to realize his individual human potential. If the world's people decide to strive for this second outcome rather than the first, the sooner they begin working to attain it, the greater will be their chances of success. (23-24) TLG also acknowledges:

These conclusions are so far-reaching and raise so many questions for further study that we are quite frankly overwhelmed by the enormity of the job that must be done. (24)Addressing population growth, TLG zeroes in one of the reasons for the exponential population explosion in the 20th century:

With the spread of modern medicine, public health techniques, and new methods of growing and distributing foods, death rates have fallen around the world. World average life expectancy is currently about 53 years and still rising. On a world average the gain around the positive feedback loop (fertility) has decreased only slightly while the gain around the negative feedback. loop (mortality) is decreasing. The result is an increasing dominance of the positive feedback loop … (37)

In other words, several elements of the world system have enabled the population to grow exponentially. LTG explains further:

The exponential growth of demand for food results directly from the positive feedback loop that is now determining the growth of human population. The supply of food to be expected in the future is dependent on land and fresh water and also on agricultural capital, which depends in turn on the other dominant positive feedback loop in the system-the capital investment loop. Opening new land, farming the sea, or expanding use of fertilizers and pesticides will require an increase of the capital stock devoted to food production. The resources that permit growth of that capital stock tend not to be renewable resources, like land or water, but nonrenewable resources, like fuels or metals. Thus the expansion of food production in the future is very much dependent on the availability of nonrenewable resources. Are there limits to the earth's supply of these resources? (54)

One of the results of population growth caused by resource us is pollution. LTG points out:

Man's concern for the effect of his activities on the natural environment is only very recent. Scientific attempts to measure this effect are even more recent and still very incomplete. We are certainly not able, at this time, to come to any final conclusion about the earth's capacity to absorb pollution. We can, however, make four basic points in this section, which illustrate, from a dynamic, global perspective, how difficult it will be to understand and control the future state of our ecological systems. These points are: 1. The few kinds of pollution that actually have been measured over time seem to be increasing exponentially. 2. We have almost no knowledge about where the upper limits to these pollution growth curves might be. 3. The presence of natural delays in ecological processes increases the probability of underestimating the control measures necessary, and therefore of inadvertently reaching those upper limits. 4. Many pollutants are globally distributed; their harmful effects appear long distances from their points of generation. (69)

There is no doubt today that the deleterious effects of pollution are everywhere: the air, the water and the soil, all in the form of billions of tons of solid waste. All this not only affects people, but also animals, plants and, on a microscopic level, bacteria and viruses. In a simple overview of the systemic nature of the problematique, TLG links these issues together:

Of course, none of the five factors we are examining here is independent. Each interacts constantly with all the others. We have already mentioned some of these interactions. Population cannot grow without food, food production is increased by growth of capital, more capital requires more resources, discarded resources become pollution, pollution interferes with the growth of both population and food. (89)

The Crux of the Matter: “A Choice of Limits”

The heart of the problem has to do with the way that we solve social problems:

But the relationship between the earth's limits and man's activities is changing. The exponential growth curves are adding millions of people and billions of tons of pollutants to the ecosystem each year. Even the ocean, which once appeared virtually inexhaustible, is losing species after species of its commercially useful animals. (151)

After demonstrating the crisis facing the whaling industry around 1972, TLG points out that there were agreed upon limits to whaling to preserve the whale population. By extension, then, the report argues:

The basic choice that faces the whaling industry is the same one that faces any society trying to overcome a natural limit with a new technology. Is it better to try to live within that limit by accepting a self-imposed restriction on growth? Or is it preferable to go on growing until some other natural limit arises, in the hope that at that time another technological leap will allow growth to continue still longer? For the last several hundred years human society has followed the second course so consistently and successfully that the first choice has been all but forgotten. (151-153)

TLG make a point that they:

… are searching for a model output that represents a world system that is: 1. sustainable without sudden and uncontrollable collapse; and 2. capable of satisfying the basic material requirements of all of its people. (158)

To achieve a stable population, the number of births would more or less have to equal the number of deaths. TLG states:

Such a requirement, which is as mathematically simple as it is socially complicated, is for our purposes an experimental device, not necessarily a political recommendation. (159-160)

At the same that TLG discusses socially complicated limits, they acknowledge that:

Technological advance would be both necessary and welcome in the equilibrium state. A few obvious examples of the kinds of practical discoveries that would enhance the workings of a steady state society include:

• new methods of waste collection, to decrease pollution and make discarded material available for recycling;

• more efficient techniques of recycling, to reduce rates of resource depletion;

• better product design to increase product lifetime and promote easy repair, so that the capital depreciation rate would be minimized;

• harnessing of incident solar energy, the most pollution-free power source;

• methods of natural pest control, based on more complete understanding of ecological interrelationships;

• medical advances that would decrease the death rate;

• contraceptive advances that would facilitate the equalization of the birth rate with the decreasing death rate.

TLG continues:

As for the incentive that would encourage men to produce such technological advances, what better incentive could there be than the knowledge that a new idea would be translated into a visible improvement in the quality of life?

They clarify the social reality of new inventions through history:

Historically mankind's long record of new inventions has resulted in crowding, deterioration of the environment, and greater social inequality because greater productivity has been absorbed by population and capital growth. There is no reason why higher productivity could not be translated into a higher standard of living or more leisure or more pleasant surroundings for everyone, if these goals replace growth as the primary value of society. (177-178)

TLG concludes:

If there is cause for deep concern, there is also cause for hope. Deliberately limiting growth would be difficult, but not impossible. The way to proceed is clear, and the necessary steps, although they are new ones for human society, are well within human capabilities. Man possesses, for a small moment in his history, the most powerful combination of knowledge, tools, and resources the world has ever known. He has all that is physically necessary to create a totally new form of human society-one that would be built to last for generations. The two missing ingredients are a realistic, long-term goal that can guide mankind to the equilibrium society and the human will to achieve that goal. Without such a goal and a commitment to it, short-term concerns will generate the exponential growth that drives the world system toward the limits of the earth and ultimate collapse. With that goal and that commitment, mankind would be ready now to begin a controlled, orderly transition from growth to global equilibrium. (183-184)

Why the Attacks on Limits in Particular and Environmentalism in General?


The Limits to Growth received strong criticism after its publication. It came in many forms. The Limits to Growth threatened specific groups. As Ugo Bardi explains:

In 1997, the Italian economist Giorgio Nebbia, noted that the reaction against the LTG study had arrived from at least four different fronts. One was from those who saw the book as a threat to the growth of their businesses and industries. A second set was that of professional economists, who saw LTG as a threat to their dominance in advising on economic matters. The Catholic world provided further ammunition for the critics, being piqued at the suggestion that overpopulation was one of the major causes of the problems. Then, the political left in the Western World saw the LTG study as a scam of the ruling class, designed to trick workers into believing that the proletarian paradise was not a practical goal. And this by Nebbia is a clearly incomplete list; forgetting religious fundamentalists, the political right, the believers in infinite growth, politicians seeking for easy solutions to all problems and many others.

So, when Limits came out, no doubt that business, industry, economists, religion, politicians, true believers in capitalism, and even workers thought that limiting growth would diminish their respective claims to authority and, most certainly, their lifestyle. This certainly fits, as asserted earlier in this article, that science is a threat to the authority of the status quo.


One Persistent Critic


Although there were many critics and criticisms, one of the most cogent and insistent came from economist Julian Simon. For example, Simon, in his 1995 Cato Policy Report “The State of Humanity: Steadily Improving,” continued his by then multi-decade rejection of the idea of limits to growth by asserting that [Italics added]:

We have seen extraordinary progress for the human enterprise, especially in the past two centuries. Yet many people believe that conditions of life are generally worse than in the past, rather than better.

I must say that nowhere in any environmental studies have I found that assertion, that “conditions of life are generally worse than in the past, rather than better.” Simon is setting this up as a straw man argument, which he easily demolishes with evidence on the improved living conditions of millions, if not billions, of people in our modern age.


In point of fact, these are ideas that TLG agrees with:

With the spread of modern medicine, public health techniques, and new methods of growing and distributing foods, death rates have fallen around the world. World average life expectancy is currently about 53 years and still rising. (37)

Hence, no sensible person, scientist or not, would assert what Simon claims they are asserting. In point of fact, the LTG was quite clear in stating that problems from overpopulation and pollution, plus potential shortfalls of resources, would become paramount well into the future:

…the limits to growth on this planet will be reached sometime within the next one hundred years. (23)

So, LTG is talking about 100 years from 1972, not as Simon claims. And, LTG does not assert, as Simon says they do, that that life is worse now than in the past. However, this is not to entirely dismiss what Simon says. He does develop a provocative thesis when he writes:

The most extraordinary part of the resource-creation process is that temporary or expected shortages -- whether due to population growth, income growth, or other causes -- tend to leave us even better off than if the shortages had never arisen, because of the continuing benefit of the intellectual and physical capital created to meet the shortage. It has been true in the past, and therefore it is likely to be true in the future, that we not only need to solve our problems, but we need the problems imposed upon us by the growth of population and income.

Simon clarifies why he thinks increased population is a benefit to mankind:

The most important benefit of population size and growth is the increase it brings to the stock of useful knowledge. Minds matter economically as much as, or more than, hands or mouths. Progress is limited largely by the availability of trained workers. The main fuel to speed the world's progress is the stock of human knowledge. And the ultimate resource is skilled, spirited, hopeful people, exerting their wills and imaginations to provide for themselves and their families, thereby inevitably contributing to the benefit of everyone.

Simon argues that over the long haul things would continue to get better just as they had been doing for the past two centuries:

The process operates as follows: More people and increased income cause problems in the short run--shortages and pollutions. Short-run scarcity raises prices and pollution causes outcries. Those problems present opportunity and prompt the search for solutions. In a free society solutions are eventually found, though many people seek and fail to find solutions at cost to themselves. In the long run the new developments leave us better off than if the problems had not arisen. This theory fits the facts of history.

This is actually fascinating, because when Simon writes that when things go bad, “those problems present opportunity and prompt the search for solutions,” he actually sounds like an environmentalist. And, he would seem to agree with LTG which says “technological advance would be both necessary and welcome...”


On another point, Simon misses the mark when he claims “there is little scientific literature on the relation of population to war.” Actually, according to Steven A. LeBlanc, there is sound evidence that “ecology and warfare intertwined today, just as they have been for millions of years.” LeBlanc explains:

The consequences of environmental stress will be scarce resources, and the consequences of scarce resources will be warfare. (Constant Battles, 12)

Simon, though, seems to go off his rocker in further explaining the need for and the capacity to invent solutions:

We have in our hands now--actually, in our libraries--the technology to feed, clothe, and supply energy to an ever-growing population for the next 7 billion years.

No doubt we do have the technology through knowledge in our libraries, but, 7 billion years? A bit of an exaggeration, perhaps.


Simon presents his argument as a universal for the ages, that we could apply his assertions to when he was writing, to 7 billion years in the future and to our now of 2019. As such, he would, at least up to now, be wrong. There is no indication that we have policy solutions to our current woes of overpopulation, seemingly insidious pollution (such as Roundup causing cancer, CO2 driving global warming or plastic refuse overwhelming both land and sea), and stresses over resource shortages, such as a lack of arable land and lack of water from droughts.


In fact, the very business and technical community that is creating the progress supporting our modern lifestyle is actually doing the opposite of Simon’s prediction that environmental problems would “prompt the search for solutions.” Business, in general, consistently lobbies against environmental action that effectively stops our politicians from taking any meaningful action. As we see today, President Trump is actually repealing environmental regulations.


Conclusion


The Limits to Growth raised key environmental concerns about population growth, pollution, depletion of resources and a deteriorating environment. These were ideas new to the public and new to policy makers in 1972. Today in 2019 they are foundational concepts in biology, ecology and environmental studies. The MIT researchers who wrote TLG studied these problems as part of an ecological system, not, in the then traditional way as isolated events. To top it off, we were given sound policy advice fifty years ago. Instead of listening, we tried to kill the messenger. To this day, it is advice ignored by policy makers.

What Happened in 2015 that Changed the World? "Peak Cement" may Signal the Turning Point of Civilization

"Peak Cement" may have taken place in 2015, stopping the exponentially growing curve that would have led us to turn the Earth into a bowling ball, similar to the fictional planet Trantor, Galactic capital in Isaac Asimov's series "Foundation" (image source).

When giving an example of an exponentially growing production curve, I used to cite cement production. Look at the data up to 2013: a beautiful growing curve with a doubling time of -- very roughly -- 10 years. Then, if we assume that the current concrete covered area in the world is about 2%  (an average of the data by Schneider et al., 2009 and the Global Rural-Urban Mapping Project, 2004) then we would get to Trantor -- bowling ball planet -- in some 50 years.

Of course that wasn't possible, but it was still a surprise to discover how abrupt the change has been: here are the most recent data (the value for 2018 is still an estimate from cemnet.com)

Impressive, right? Steve Rocco, smart as usual, had already noticed this trend in 2017, but now it is clearer. It looks like a peak, it has the shape of a peak, it gives the impression of a peak. Most likely it is a peak -- actually, it could be the start of an irreversible decline in the global cement production.

Now, what caused the decline? If you look at the disaggregated data, it is clear that the slowdown was mainly created by China, but not just by China. Several countries in the world are going down in terms of cement production -- in Italy, the decline started in 2010.

My impression -- that I share with the one proposed by Rocco -- is that this is not a blip in the curve, nor a special case among the various mineral commodities produced nowadays. It is a symptom of a general problem: it may be the clearest manifestation of the concept of "peak civilization" that the 1972 "Limits to Growth" study had placed for some moment during the 1st or 2nd decades of the 21st century.

Peak Cement is not alone another major peak was detected by Antonio Turiel for diesel fuel in 2015.








And, of course, we know that another major commodity went through a global peak in 2014: coal. (data from bp.com)

  

So, are we really facing "peak civilization"? It is hard to say. On a time scale of a few years, many things could change and, in any case, you don't expect peaking to take place at the same time for all mineral commodities, everywhere. A strong indication that the whole world system is peaking would come from the behavior of the global GDP. Rocco had proposed that also the GDP had peaked in 2015, but the data available at present are insufficient to prove that.

In any case, it has been said that we would see the great peak "in the rear mirror"and this may well be what we are seeing. Whatever is happening it will be clearer in the future but, if it is really "the peak", expect the Seneca cliff to open up in front of us in the coming years. And maybe it won't be such a bad thing(*): did we really want to turn the Earth into a bowling ball?





(*) Antonio Turiel lists in a post of his (in Spanish) all the advantages ensuing from a societal collapse: reducing emissions, less pollution, a saner society and more)

Why Economists Can't Understand Complex Systems: Not Even the Nobel Prize, William Nordhaus

The "base case" scenario of "The Limits to Growth" 1972 report to the Club of Rome. The strong non-linearity of the behavior of complex systems -- including the global economy -- is nearly impossible to understand for people trained in economics. William Nordhaus, the recent Nobel prize winner in economics, is no exception to the rule. In this post, I'll report how, at the beginning of his career, Nordhaus criticized "The Limits to Growth", showing in the process that he had understood nothing of the way complex systems work.

After having been awarded the Nobel prize in economics of this year, William Nordhaus has been often presented as some sort of an ecologist (see, e.g. this article on Forbes). Surely, Nordhaus' work on climate has merit and he is one of the leading world economists who recognize the importance of the problem and who propose remedies for it. On the other hand, Nordhaus' approach on climate can be criticized: he tends to see the problem in terms of costs and solvable just by means of modest changes.

Nordhaus' approach to climate change mitigation highlights a general problem with how economists tend to tackle complex systems: their training makes them tend to see changes as smooth and gradual. But real-world systems, normally, do what they damn please, including crashing down in what we call the Seneca Effect.

On this point, let me tell you a little story of how Nordhaus started his career at Yale by an all-out attack against system dynamics, the method used to prepare the 1972 study "The Limits to Growth," showing in the process that he had understood nothing on the way complex systems work.

In 1973, Nordhaus published a paper titled "Measurements without Data." It was directed specifically against Jay Forrester, the founder of system dynamics, accusing him of having developed a model able only to describe a world existing only in his (Forrester's) imagination. If you know something about how scientists think, you may understand that this is not just an accusation: it is an insult. And Nordhaus' paper didn't mince words, even getting into direct and personal accusations against Forrester, for instance that he was favorable to the extinction of the human race, that he lacked humility, that he wasn't testing his assumptions, that he ignored the previous literature, that his model was the equivalent of a "widow cruse", and a few more quips.

Nordhaus's attack was one of the first broadsides against world dynamics, possibly the pebble that originated the avalanche of political criticism that gave a bad name to "The Limits to Growth" in the 1980s and 1990s. To get some idea of the adversarial atmosphere of the time, note that, contrarily to all normal procedures in science, the editor of the journal that published Nordhaus' paper refused to publish Forrester's rebuttal - he was forced to publish it in a much less known journal, where it remained basically unknown while the "Limits-bashing" went on.

But what was the substance of Nordhaus's criticism? Nearly half a century after the publication of his paper, it would make little sense to go into the details of its 29 pages, dense with formulas and reasoning. Basically, the paper demonstrates how Nordhaus just didn't understand Forrester's ideas and methods, claiming over and over that standard economics was a better tool to describe the world system. He couldn't understand -- just as most modern economists can't -- that standard economics doesn't account for the kind of oscillations -- including crashes - which are observed in history and that system dynamics describes very well.

This is an especially serious limitation when dealing with the earth's climate, which is a complex system subjected to abrupt changes and tipping points: here the approach of economists is not only wrong but outright dangerous because it leads decision makers to a false sensation of safety and control which, in reality, we don't have.

The whole story is told in some detail in my book "The Limits to Growth Revisited" (Springer 2011. Below, an excerpt dedicated to Nordhaus's criticism

_________________________________________________

From "The Limits to Growth Revisited"
by Ugo Bardi, 2011


We can now examine the work of William Nordhaus, who emerged out of the debate as one of the major critics of the LTG study and, in general, of system dynamics as a method for modeling economic systems. In 1973, Nordhaus published a paper titled “World dynamics: measurements without data” [Nordhaus 1973] taking as a target Forrester’s book [Forrester 1971]. However, it is clear that Nordhaus’s attack broadly included also the LTG work.

Nordhaus's paper spans 27 pages and contains much material worth discussing, but it would be out of scope to go into all the details here. Forrester himself used 21 full pages in his response that was published in “Policy Sciences” [Forrester et al 1974]. For what we are concerned here, we may summarize Nordhaus's criticism as pertaining to basically three categories: 1) accusations ad personam, 2) unsubstantiated statements of disbelief and 3) quantifiable criticism.

As for the first category, we can take as an example the accusation of “lack of humility,” made against Forrester. The gist of this accusation is that carrying world simulations all the way to the end of the 21st century is much too ambitious to make sense. This is a legitimate opinion, but not something that can be evaluated on the basis of objective criteria. On this point, however, it is worth noting that Nordhaus himself, later on, committed the same intellectual fault – according to his own definition - with his DICE (Dynamic Integrated Climate Economy) model [Nordhaus 1992, (b)].

The second category of criticism from Nordhaus, “statements of disbelief,” collects alleged shortcomings of world modeling which, however, are not substantiated by actual proof. One such statement, taken as an example, is the following: (p. 1166)

“..we discover dramatic returns to scale of the economy: if we double both the number of blast furnaces and the number of ore fields the output of pig iron quadruples”

But nowhere in his paper does Nordhaus demonstrate that Forrester's model produces such obviously unrealistic results. In fact, Nordhaus is simply looking at one of the several equations of the model without realizing that the output of each equation will be modified by the interaction with all the other equations and that will insure correct returns to scale. This is the essence of systems thinking: that parts interact.

Let’s now consider the accusation of “measurements without data” which is the most important part of the paper and gives it its title. This is a quantifiable criticism: if it can be shown that Forrester (or the LTG group) were making models which are totally unable to describe the real world, then it is correct to dismiss their work as useless and irrelevant.

In “World Dynamics” (1971) and in “The Limits to Growth” (1972) one thing that can be immediately noticed is that historical world data do not appear in the calculated scenarios. For a reader accustomed to the common approach of “fitting” the data, that gives a bad impression. Is it possible that the authors of these studies were really so cavalier that they did not care to compare their results to real world's data?

But a more careful examination of the text of both studies shows that the authors do state that their calculations were calibrated on actual historical data. Not showing these data in the figures was a choice made in order to improve clarity. As a choice, it may be criticized, but not ignored.

On this point, note also that, in the “Models of Doom” book [Cole et al 1973] examined before, none of the several authors engaged in the study felt that Forrester’s work (or the LTG book) could be criticized in the terms used by Nordhaus. In the chapter by Cole “The Structure of the World Models” [p. 31 of Cole et al 1973] the data used in the models are examined in detail. Some of the approximations utilized are criticized and in some cases it is said that the data are insufficient for the purposes of the model. But it is never stated that the models were “without data”.

So, it is clear that the world2 (Forrester's) and world3 (LTG) were calibrated to the historical data – at least within some limits. On this point, although both Forrester and the LTG team made an effort of choosing the parameters of the model on the basis of historical data, they also felt that their models had a heuristic rather than explicitly predictive objective. Therefore, there was no need for their scenarios to use a rigorous data fitting procedure of the type used in physical studies. Again, this is an attitude that can be criticized, but that cannot be ignored.

Forrester himself describes this attitude in his book “World Dynamics”” [Forrester 1971]. On page 14 (2nd edition) he says:

There is nothing new in the use of models to represent social systems. Everyone uses models all the time. Every person in his private life and in his community life uses models for decision making. The mental image of the world around one, carried in each individual’s head, is a model. One does not have a family, a business, a city, a government, or a country in his head. He has only selected concepts and relationships that he uses to represent the real system. <..> While none of the computer models of social systems existing today can be considered as more than preliminary, many are now beginning to show the behavioral characteristics of actual systems.

System scientists have a structured approach on this point, as described, for instance, by Sterman [Sterman 2002, p. 523].

… it is important to use proper statistical methods to estimate parameters and assess the ability of the model to replicate historical data when numerical data are available <..> Rigorous defining constructs, attempting to measure them, and using the most appropriate methods to estimate their magnitudes are important antidotes to causal empiricism, muddled formulations and the erroneous conclusions we often draw from our mental models. Ignoring numerical data or failing to use statistical tools when appropriate is sloppy and lazy”

Of course, the very fact that Sterman feels that it is necessary to criticize those modelers who “fail to use statistical tools” indicates that the problem exists. Modeling socio-economic systems using system dynamics tools is not immune to the biases that are easy to see in the ordinary political debate.

So, taking into account all this, how should we understand Nordhaus's criticism? If it is intended as meaning that system dynamics models provide only approximations of the historical behavior of the world, then it is a weak criticism that hardly justifies the statement “measurements without data.” This point must have been clear to Nordhaus himself, who tried to substantiate his criticism by the following statement, referred to Forrester's world2 model (emphasis in the original) :

…..contains 43 variables connected to 22 non-linear (and several linear) relationships. Not a single relationship or variable is drawn from actual data or empirical studies. 

Let’s analyze this sentence. First of all, Forrester's model, as all models, contains three elements: the mathematical relationships, or equations, the variables (populations, resources, etc.) and the constants which appear in the equations and which determine the quantitative behavior of the model. Nordhaus speaks here only of two of these elements: variables and relationships, but not of the third; the constants. Clearly, he was aware that Forrester was using constants derived from real world's data. But, then, what does it mean that “Not a single relationship or variable is drawn from actual data or empirical studies”?

Evidently, Nordhaus thinks that the equations and the variables of the model should have been determined by fitting the experimental data. This is an approach that often goes under the name of “econometrics.” This term does not describe a specific type of model, but it refers to a series of methods and techniques used to fit a set of data, typically a time series, to a model [Franses 2002]. Econometrics can be used to test a model but, in some cases, it is the “best fit” of several models that determines which one is to be chosen. This is a legitimate technique, but one that may easily lead the modeler astray if the physical elements of the system are not sufficiently understood.

In any case, the “best fit procedure” tells you little about the physics of the system being studied. Think of Newton's law of universal gravitation. The scientists who worked before Newton on planetary motions, from Ptolemy to Johannes Kepler, had basically used a “data fitting” procedure to describe their observations but never could derive the law of universal gravitation using that approach. Instead, Newton devised a law that he thought plausible. Maybe he got the idea watching an apple falling from a tree, but that hardly qualifies as data fitting. Then, he calculated the motion of the planets according to his law. He found that simulated bodies orbiting around the Sun would describe elliptical orbits, just as it was observed for the planets. At this point, he could vary the “g” constant in his law in such a way that it was possible to use the equation to describe the movement of real planets.

So, if Nordhaus’ criticism to Forrester were to be applied to Newton’s gravitation law, then one should criticize it because it is not “drawn from actual data or empirical studies” One could actually criticize Newton for performing “measurements without data.”

Of course, Forrester’s model is much more approximate and tentative than Newton's law of universal gravitation. Nevertheless, the considerations about the validation of the model remain valid. So, in order to prove his point, “Measurements without data”, Nordhaus needs to do more. He needs to demonstrate that Forrester's model is totally unable to describe reality.

So, Nordhaus sets up in his paper to “evaluate the specific assumption in the subsectors of World Dynamics.” (p. 1160). The examination of the population subsystem is crucial in this analysis. In fig 3 of his article, Nordhaus plots data on the birth rate as a function of the Gross National Product for several countries, together with what he claims to be the results produced by Forrester's model.

Figure 15. Nordhaus model of the population subsector in Forrester's “World Dynamics.” From Nordhaus 1973


From this figure, it would seem that Forrester’s assumptions are completely wrong and this is, indeed, Nordhaus's conclusion. But what is the curve that Nordhaus calls “Forrester’s assumption”? In the article, we read that this curve is “Forrester’s assumed response of population to rising per capita non-food consumption when population density, pollution and per capita food consumption is held constant” (emphasis added).

But this is not Forrester’s assumption. Nordhaus had simply taken one of the equations from Forrester's model and had plotted it keeping constant all parameters except one (the “non-food consumption” that he equates to GNP). But Forrester’s model was never meant to work in this way. [..] In the “world3” model all the equations need to be solved together to make the model work as it is supposed to. Nordhaus’s obvious mistake was noted and described by Forrester himself [Forrester 1974]:

“The case made by Nordhaus against the population sector of World Dynamics rests on the use of real-world data that he attempts to relate to model assumptions. However, Nordhaus incorrectly compares a single dimensional relationship in world dynamics (between net birth rate and material standard of living) with time series data. He fails to account for the presence of other variables influencing the time series. As a result, he erroneously asserts that the model is inconsistent with the data. In fact, the data Nordhaus present support the validity of the World Dynamics model assumptions.”

Subsequently, Forrester runs his complete model and produces the following figure:

Figure 16 – Forrester’s response to Nordhaus


In this figure, we see that the behavior of birth rates as a function of GNP produced by Forrester's model is qualitatively consistent with the historical data. Later on, Myrtveit [2005] re-examined the question and arrived at the same conclusion.

It appears clear from this discussion that Nordhaus, in his criticism of Forrester's book, had missed some basic points of the methods and the aims of world modeling by system dynamics. Unfortunately, however, Nordhaus’s 1973 paper left a strong imprint in the successive debate, owing in part to Nordhaus’ reputation and in part to the fact that Forrester’s response [Forrester 1974] wasn’t so widely known, mainly because it was published in a scarcely known journal (Policy Sciences) which wasn't even dedicated to economics.

On this issue, it is surprising that the editors of the “Economic Journal,” who published Nordhaus’s paper, did not ask Forrester to reply; as it is a common policy, and even courtesy, in cases such as this one. We have no record that Forrester asked to the “Economics Journal” to publish his rebuttal, but that was the obvious first choice for him if he wanted to reply to Nordhaus; as he did. Consequently, it seems probable that the editors of the “Economic Journal” refused to publish Forrester's reply and that for this reason he was forced to publish it in another journal. Another indication that the debate about world modeling was especially harsh and that it did not follow the accepted rules for this kind of exchange.

[..]

The debate about world modeling by system dynamics flared again, briefly, in 1992, when three of the authors of the first LTG book (the two Meadows and Jorgen Randers) published a sequel with the title “Beyond the Limits” [Meadows et al. 1992]. In this second book, the authors updated the calculations of the first LTG study, obtaining similar results. The publication of “Beyond the limits” generated a new response from William Nordhaus; this time with the title of “Lethal Models” [Nordhaus 1992]. This new paper took up again some of the earlier arguments put forward by Nordhaus in his 1973 paper, but with considerable differences. 

Facing the 43 pages of Nordhaus' 1992 paper, we immediately see that it does not contain anymore the ad personam attacks of his first paper on this subject [Nordhaus 1973]. On the contrary, Nordhaus explicitly thanks the authors of LTG for their comments and their assistance. We also see that this paper does not contain anymore the accusation of “measurements without data” that was the main theme of Nordhaus's 1973 paper. All that Nordhaus has to say in this respect is (p. 14):

In Limits I, no attempt was made to estimate the behavioral equations econometrically, although some attempt seems to have been made to calibrate some of the equations, such as the population equation, to available data.

It appears that this is not the only point where Nordhaus is backtracking. On  page 15, for instance, we read that,

“the dynamic behavior of the enormously complicated LTG was not fully understood (or even understandable) by anyone, either authors or critics”

And we may wonder whether with these “critics” Nordhaus intended also himself.

___________________________________________

You can find Nordhaus paper here:

http://static.stevereads.com/papers_to_read/world_dynamics-_measurement_without_data_.pdf

And Jay Forrester's rebuttal here.

https://link.springer.com/article/10.1007/BF00148039

Did the Club of Rome Ever Disavow "The Limits to Growth"? A Story of Ordinary Disinformation

Aurelio Peccei in 1969, when he was appointed the first president of the Club of Rome

The Club of Rome is inextricably linked to the legendary report that it commissioned to a group of MIT researchers in 1972, "The Limits to Growth." Today, nearly 50 years later, we still have to come to terms with a vision that contradicts the core of some of humankind's most cherished beliefs. The report tells us that we cannot keep growing forever and that we have to stop considering everything we see around us as ours by divine right. 

Not surprisingly, the report generated strong feelings and, with them, there came plenty of disinformation and legends. Some cast the Club of Rome in the role of a secret organization with dark and dire purposes, others aimed at the Limits report, claiming that it was "wrong" or, worse, purposefully designed to deceive the public. I wrote an entire book on this subject (The Limits to Growth Revisited): in short, most of these stories are false but some contain grains of truth and all of them tell us something about how we humans don't just deny bad news, we tend to demonize the bearers.

One of these legends states that the leaders of the Club of Rome disavowed their brainchild, The Limits to Growth and, in doing so, they admitted that it had been not only wrong, but actually an attempt to mislead the public. It is an old legend but, as all legends, it is surprisingly persistent and you can still see it mentioned in recent times (for instance, here and here) as if it were the obvious truth. It is not: it is a good example of how disinformation works.

The origins of the legend go back to Julian Simon (1932-1998), flamboyant defender of economic growth and self-styled "doomslayer." Simon was a skilled polemicist who used with remarkable effectiveness all the standard techniques of disinformation. So, in his book, "The Ultimate Resource" (1981 edition, p. 286) Simon writes (highlighting mine)

The most compelling criticism of the Limits to Growth simulation, however, was made by the sponsoring Club of Rome itself. Just four years after the foofaraw created by the book's publication and huge circulation -- an incredible 4 million copies were sold -- the Club of Rome "reversed its position" and "came out for more growth" [..] The explanation of this reversal, as reported in "Time" is a masterpiece of face saving double talk.

"The Club's founder, Italian industrialist "Aurelio Peccei, says that Limits was intended to jolt people from the comfortable idea that present growth trends could continue indefinitely. That done, he says, the Club could then seek ways to close the widening gap between rich and poor nations -- inequities that, if they continue, could all too easily lead to famine, pollution, and war. The Club's startling shift, Peccei says, is thus not so much a turnabout as part of an evolving strategy"

In other words, the Club of Rome sponsored and disseminated untruths in an attempt to scare us. Having scared many people with these lies, the Club can now tell people the real truth. 

So, where does all that come from? I can't find on the Web the original "Time" article that Simon cites, but there are other reports available on the declarations that Aurelio Peccei (founder, and at the time president, of the Club of Rome) released in 1976, during a meeting held in Philadelphia. The journalists who interviewed Peccei were impressed by what they perceived as a reversal of previous Club's policies, to the point that Newsweek titled its report (according to the St. Louis Post) "Has the Club of Rome publicly abjured?" Peccei was said (according to the New York Times) to have stated that, "Naturally, we realize that no-growth is neither possible nor desirable,"

Is that enough to say that the Club of Rome had "reversed its position"? Not at all. There was nothing new in Peccei's statements. Already in 1973, one year after the pubblication of Limits, the Club produced a document about the report signed by the executive committee and titled "The New Threshold."   The document stated that:

An erroneous image of the Club has, therefore, formed as a group advocating zero growth. Again, the possible consequences of unregulated growth of the industrialized societies and, still more, those which would arise if growth were abruptly brought to a halt, has disturbed some of the less developed countries where, we have already said, the report is all too easily seen as a selfish proposal from the developed world which would still further aggravate the difficulties of the great mass of underprivileged on our planet.

And that is not a "face-saving double talk," as Simon claimed. It is a necessary consequence of the views of the Club from its formation. Aurelio Peccei had started the Club on the basis of what he called the "problematique" or the "predicament" of humankind. From his first public speech on this subject, in 1965 (you can find it here), it is clear that he saw the problems facing humankind mainly in terms of a fair distribution of the available resources, avoidance of wars, elimination of poverty, health care for everyone, and the like. (see also this post by Irv Mills). Peccei didn't imagine the future of humankind in terms of a collapse: the concept of "overshoot and collapse" of socioeconomic systems didn't exist at that time, it was developed and diffused only in the 1970s by Jay Forrester.

So, the results of "The Limits to Growth" study, with their scenarios of probable collapse, must have been a shock for Peccei and the other members of the Club of Rome. Still, it is clear from what they wrote afterward that they understood the logic and the consequences of the report they had commissioned - they never "disavowed" it, even though over the years some individual members criticized the study in various ways, but that's anther story.

Over the years, the Club of Rome and the Limits have been seen as the same thing, sometimes confusing who did exactly what. In reality, they are two distinct and different things. The Club of Rome had its roots in the "problematique" devised by Peccei and its members worked at integrating the Limits results within their worldview. It was clear to them that "The Limits to Growth" aggregated all the world's national economies into average parameters. As a consequence, "zero growth" as a global policy would have meant maintaining the economic gap separating the rich and the poor country. And that was not what Peccei and the others had in mind. Hence, Peccei's statement in 1976 "Naturally, we realize that no-growth is neither possible nor desirable," In another report, they said that the Limits "is a beginning and not an end." That is the origin of the other 1976 statement by Peccei "the limits‐to‐growth report had served its purpose of “getting the world's attention.”

And here we are: no lies, no disavowal, no scare tactics. What we have, instead, is a stark reminder of how disinformation works. Note the narrative technique used by Simon: he says that "Having scared many people with these lies, the Club can now tell people the real truth." You need about 3 seconds to deconstruct this statement and note how it makes no sense: if the Club successfully told lies to the public, why should it stop doing that? What could the Club possibly gain by publicly confessing of having lied? But narrative follows special rules and what we have here is a common trope of many modern movies: at some moment, the villains may explicitly confess their crimes (sometimes called badass boast) out of pure arrogance. So, the trick Simon is using here is to cast the Club of Rome into the role of the villains in narrative terms. It is an effective trick in an age in which we can't distinguish reality from narrative anymore: it is the dark art called "creating one's own reality."

Nearly 50 years have passed since the Limits report was published and it is safe to say that most people remember it the way it was described by the propaganda of the 1990s, as a "wrong-headed" study (if they remember it at all). But does that mean that it has been forgotten forever? While it is true that "Google Trends" doesn't show any increased interest in the "Limits" itself, there is growing interest in the concept of slowing down economic growth or avoiding altoghether. And "The Limits to Growth" is showing a remarkable return of interest in the scientific literature. Does that means we will see a return of interest in it also in the mainstream debate? Why not? After all, in the long run, truth always beats disinformation.

____________________________________________

Here is the article on the St. Louis Post about Peccei's declarations, with several errors resulting from OCR, but overall readable

Time magazine wrote recently in an essay on futurology, "Men hunger for predictions as they hunger for bread in a famine." The starving have recently been thrown a few loaves by the self-appointed prophets of the twentieth century. The oracular prophecies out of the computer have been muted since the oil crisis of 1973 broke the back of their optimistic curves of growth. The guild of soothsayers fell out of favor. Now after a long penitent silence they are making a comeback. Herman Kahn, director of the Hudson Institute and an unshakable optimist, has published a new study of the future entitled. "The Next 200 Years." His conclusion is that in the year 2176 the world population will have reached a total of 15 billion and will be living comfortable with a per ants than were predicted for 1975. The Wall Street Journal says the dreams of unlimited energy, cheap nuclear-generated electricity, fivefold increase in farm yields and the final victory over cancer before the end of the century can be forgotten. The "revised future" looks somewhat different. By the year 2000 food will be three times as dear as it is now, hot counting currency inflation. Automatic highways will not be built. At best, automobiles will have a more efficient fuel consumption. The super-jumbo jets with 1000 seats will not be flying by the end of the '70s, but at the earliest, by the '90s. The future was being revised in Philadelphia also. "Has the Club of Rome publicly abjured?" asked Newsweek, in view of its new slogan. The club, a loose association of about 100 industrialists and academics from various countries, has been regarded so far as a stern warning against too optimistic forecasts. If the present growth trend continues, it said in 1972, the limits of growth would be reached sometime within the next 100 years. Aurelio Peccei, founder of the Club of Rome, denied in Philadelphia that its members had put themselves forward as capita income of about $20,000. Kahn's collaborator, Edmund Still-man, in a study commissioned by a French private bank, prophesies a particularly rosy future for the French. Very soon after 1980 France will overtake West Germany in production of goods and services to become Number One in Europe. The "Club of Rome," which in 1972 postulated the "limits of growth" and attracted powerful criticism, has come up with a slightly less pessimistic view of the world. Its new motto is "organic growth" and the optimistic slogan for its latest congress in Philadelphia was "New Horizons for Humanity." In a 10-part series the Wall Street Journal discusses which of the prophecies made 10 years ago have come true and which of them have to be corrected. The paper's researchers have found that the biggest mistake made by the futurologists has been their projections of population growth. On the one hand a birth explosion and a declining death rate in the developing countries have combined to increase the total world population much faster than anticipated. But in the United States, for instance, the trend is reversed. Already now there are 12,000,000 fewer inhabit advocates of zero population growth. Their study "Limits of Growth" which has sold in the meantime, 2,000,-000 copies was only intended, he says as a shock and a way of directing public attention to the problems. "Naturally we realize that no-growth is neither possible nor desirable," he said. According to the modified formula, developed by the West German, Prof. Eduard Pestel, and his American colleague, Mihailo Mesarovic, what is needed now is "directed growth." "The important thing is in which way growth takes place, with what technology and in what branches of the economy," said Professor Ervin Laszlo of the United Nations Institute for Training and Research. The outlines of a new world economic order are being drawn up in a new study commissioned by the Club of Rome from the Dutch economist and Nobel prizewinner Jan Tinbergen. Working with 20 other experts, he expects to have it ready by autumn of this year. The rough outline was already plain in Philadelphia larger currency reserves for the speedier financing of development projects in the Third World, stricter control of the multinational concerns and a world-wide co-ordinator of energy 'Men hunger for predictions as they hunger for bread in a famine . . .

The View From Les Houches: What Are Models For?

Sandra Bouneau, researcher and lecturer at the university of Paris-Sud, shows her model at the School of Physics in Les Houches, France, in March 2018. As you can see from the image, her model is complex and detailed. It is one of the several models presented at the school which attempt to describe the trajectory of the transition.

Overall, all the models based on physics (including Bouneau's one, as far as I understood it) arrived to similar conclusions, confirming the calculations that myself, Denes Csala, and Sgouris Sgouridis published in 2016. In practice, the transition is possible, but it won't happen all by itself. The economic system needs to be pushed in the right direction, in such a way that it will be able to provide the necessary investments.

The problem is that the system is not being pushed hard enough. Some parts of it, including the US governments, are pushing in the wrong direction, dreaming of an impossible "energy dominance" (and even if it were possible, what good would it be for America?).

At the bottom of the whole problem, it is the fact that policy-makers don't believe in models, although they may declare the opposite. There have been many models developed during the past century or so which would have created a different world if the powers that be had acted on the advice provided - first and foremost "The Limits to Growth" of 1972. But that model was not only disbelieved but positively demonized.

In the end, All models are made to search for trajectories which avoid collapse, so ignoring models ensures collapse. And that's what we are doing!

The Seneca Paradox: if mineral depletion is a problem, how is it that we don't see its effects?

With oil prices remaining low and with production apparently more than sufficient to satisfy the demand, most people have jumped to the conclusion that all mineral resources are abundant and not a concern for the foreseeable future. Yet, the problem remains: mineral resources are not infinite. The solution to the conondrum may be in the "Seneca Effect." It is an insidious kind of effect that hides future risks behind an apparently safe and robust growth. 

The story of the Club of Rome starts with the issue of natural resources. In the 1960s, it had become clear to the Club's founder, Aurelio Peccei, that the world's resources were finite and to ask the question of how that was to affect humankind. It was the origin of the first and the best-known report to the Club of Rome, "The Limits to Growth," published in 1972.


The 1972 report already provided answers to the question of depletion. It turned out that resource scarcity would limit the growth of the world's economy and, eventually, lead it to decline. This conclusion was often misunderstood as meaning that humankind would soon "run out" of oil, gas, or some other resource; but that was never stated in the report and it never was the point.


In 2014, the Club of Rome produced another report titled "Extracted" in English and "Der Geplunderte Planete" in German that reiterated the earlier conclusions. The author of the report, Ugo Bardi, a researcher at the University of Florence, Italy, concluded that the problem of mineral depletion was real and that it was progressively getting worse.

Yet, these conclusions are far from being generally accepted. Depletion, it seems, is still considered a non-problem, especially in the extractive industry. "If depletion is really a problem," industry representatives often say, "how come that we are still producing mineral commodities at the highest rates ever seen in history? Besides, we observe that our production costs are not significantly increased when we use lower grade ores."

So, is mineral depletion an existential threat to human civilization? Or is it just a marginal problem that can be fixed by some technological improvements? This is truly a fundamental question for the future of humankind. An answer is provided by the latest report to the Club of Rome that was published in 2017, "The Seneca Effect."

Taking inspiration from something that the ancient Roman philosopher Seneca said, the author of the study, Ugo Bardi, examines the trajectory of an economic system subjected to the dual strain of mineral depletion and pollution. The result is the "Seneca Curve", a graphical depiction of Seneca's statement that "Increases are of sluggish growth, but the way to ruin is rapid." It is something well known in everyday life, but the study could confirm it using mathematical models. Here is the curve as calculated by simulations.

The "Seneca Effect" or the "Seneca Paradox" explains why mineral depletion is a problem but, at present, we are not feeling its effects. We haven't yet reached the summit of the curve and we are not seeing the cliff awaiting us. So far, the extractive industry has been able to mask the effects of depletion by means of economies of scale. That has been possible as long as production keeps increasing, which has been the case up to now for most mineral commodities. The problem is that this strategy cannot last forever: mineral resources are not infinite. 

A good example of this effect can be found in the oil industry. At present, all fears of "running out" of oil seem to have been dispelled by the low market prices and by the still increasing production. Both factors give the impression of an abundance of cheap oil that could last for a long time - if not forever. But this is exactly the result of the shape of the Seneca Curve. As long as we don't reach the start of the cliff, we don't see it. 

But ruin, as Seneca said, may be rapid. Consider the current climate situation and the urgent need of reducing carbon emissions. Consider the rapid switch to electric vehicles, often seen as a way to fighting climate change. Consider that in the US more than 60% of the market for crude oil product is for private vehicles. Then, you see that if people were to start replacing their old cars and trucks with electric ones (something that they should do by all means for the sake of our survival), the oil industry would lose a big bite of its market. 

For the oil industry, losing a significant fraction of their market is not just a question of downsizing;  it is their death knell. It is here that the "Seneca Effect" starts playing its role. The economies of scale which had allowed the industry to overcome the effects of depletion become diseconomies of scale, increasing costs and reducing profits. The industry becomes unable to attract new investments; it starts shrinking and eventually disappears: it is what Seneca said, "ruin is rapid". 

The decline of the oil industry has already been ongoing in several regions of the world and the loss of efficiency due to scaling down is well documented (see, e.g. Hall et al. 2014). In recent times, the US industry has been able to start a new cycle of oil extraction with "Shale oil" (more properly, "tight oil") but that simply means to postpone the unavoidable and the Seneca Cliff of shale oil may be just around the corner. 

Humankind is facing a difficult situation right now, with the twin threats of depletion and pollution working together to cause a decline that could be very rapid, as it is has been often the case for past civilization. The "Seneca Effect" makes the situation all the more insidious because at present we have only a few hints of the future decline but when we will see the cliff in front of us it may be too late to avoid it in full. 

Yet, today we have powerful tools in the form of the science of complex systems. If we are willing to use them, these tools allow us to understand the future and to be prepared for it. If we understand the threats we face, they may be seen as opportunities. So, the impending ruin of the oil industry is not a threat but an opportunity to avoid, or at least mitigate, a future climate disaster. 

Once we understand this point, the strategy becomes clear: do not fight the unavoidable; do not try to keep the oil industry alive at all costs; that's exactly what makes the Seneca Cliff steeper. Instead, favor the unavoidable change. it means helping the oil industry to disappear by favoring its replacement by something less polluting and more sustainable. Similar strategies are possible for many polluting industries still common today.

As always, the future is nothing but the choices we make and there is still time to make good choices. The Seneca cliff of the human civilization will happen only if we choose to make it happen.