In the 2010 film Force of Nature: The David Suzuki Movie and a related National Film Board interactive website, famed Canadian environmentalist David Suzuki indicts “suicidal” human population and economic growth by drawing an analogy between its impact on our finite planet and exponential bacterial growth in a test tube full of food. In the latter system, one bacterium divides every minute. At the beginning there is only one, but a minute later there are two bacteria. At two minutes there are four, at three minutes eight, at four minutes 16, and so on. At 59 minutes, we are told, the tube is only half full, but due to exponential growth at 60 minutes it will be full – and all the food will be gone. The camera swoops in for a close-up of Suzuki as he delivers the kicker: “Every scientist I’ve talked to agrees we’re past the fifty-ninth minute!”
Suzuki’s test tube video is available for downloading at the NFB, and no doubt it has been viewed many thousands of times, including in classrooms across the country. His film has won awards and to our knowledge the “science” in it has never been seriously challenged. True, some critics have pointed out that he does not practice what he preaches and that the long history of failed eco-catastrophic predictions should warrant more caution on his part. What is most striking to us, however, is how unoriginal Suzuki’s argument is. The impossibility of indefinite exponential growth on a finite planet has long been a basic tenet of environmentalism. Suzuki’s message, however, goes beyond the standard “living within sustainable limits” promoted by many environmentalists. The logic of his analogy is that humanity’s future is hopeless. Slowing the reproduction rate or even reducing the number of “bacteria” within a fixed or non-exponentially expanding resource supply can only delay environmental collapse, not prevent it.
Fortunately, Suzuki’s parable directly contradicts historical data on human population growth as well as food and resource availability and bears no resemblance to the actual workings of market economies. As the renowned economist Julian Simon observed after studying these issues for nearly three decades: “Population has never increased geometrically [exponentially]. It increases at all kinds of different rates historically, but however fast it increases, food increases at least as fast, if not faster. In other words, whatever the rate of population growth is, the food supply increases at an even faster rate.” The same is also true for nearly any economically valuable resource in a market economy. Paradoxically, the more people there are, the more abundant and affordable resources become over time, from food per person to reserves of fossil fuels.
Humans have evolved beyond maggots
Suzuki’s worldview is descended from that of Robert Malthus, the English author of an extraordinarily influential 1798 essay warning that population growth inevitably exhausts resources. The fundamental problem with Suzuki’s perspective is his denial, or perhaps inability to conceive, that humans are different from life forms such as bacteria, or “maggots” as he once called us, that may be governed by Malthusian dynamics. As economist Henry George famously put it in his 1879 book Progress and Poverty, of “all living things, man is the only one who can give play to the reproductive forces, more powerful than his own, which supply him with food.” This all-but forgotten tome was the most widely read economic text of the 19th century. While other creatures survive on what they find and can only grow as numerous as their food sources allow, significant increases in human numbers are possible because of our unique ability to produce more food. As George saw things:
If bears instead of men had been shipped from Europe to the North American continent, there would now be no more bears than in the time of Columbus, and possibly fewer, for bear food would not have been increased nor the conditions of bear life extended, by the bear immigration, but probably the reverse. But within the limits of the United States alone, there are now forty-five millions of men where then there were only a few hundred thousand, and yet there is now within that territory much more food per capita for the forty-five millions than there was then for the few hundred thousand. It is not the increase of food that has caused this increase of men; but the increase of men that has brought about the increase of food. There is more food, simply because there are more men.
George famously added that a key difference between animals and humans was that both “the jay-hawk and the man eat chickens, but the more jay-hawks the fewer chickens, while the more men the more chickens.” Similarly, “both the seal and the man eat salmon, but when a seal takes a salmon there is a salmon the less, and were seals to increase past a certain point salmon must diminish.” Humans, however, “by placing the spawn of the salmon under favorable conditions” can increase their number to such an extent as to more than make up for their catches. In the end, George argued, “while all through the vegetable and animal kingdoms the limit of subsistence is independent of the thing subsisted, with man the limit of subsistence is, within the final limits of earth, air, water, and sunshine, dependent upon man himself.
You don’t have to be an economist or anthropologist (or a geneticist as Suzuki was before he became a celebrity) to recognize that human beings early on developed more sophisticated survival strategies than other life forms. They created trading systems and social structures and technological innovations that over time greatly improved and even optimized the use of renewable and non-renewable resources. These led to today’s globalized market economy, a phenomenal engine of wealth creation and – where it is most unencumbered and advanced – of a net reduction in environmental impact. This perspective, however, lacks the emotive power of Suzuki’s simplistic doomsday analogy and thus requires a few more words of explanation.
The link between population growth and economic growth is immutable. More people are not merely more mouths to feed but also more arms to work and more brains to solve problems. Optimistic thinkers from all points on the philosophical spectrum, from socialist central planners to free market capitalists, have long believed that valuable resources can become less scarce over time through the application of social and technological innovations fuelled by the accumulation of manufactured and human capital. They believe the same principles can be applied to solving pollution and health problems. In such a context, population could grow almost indefinitely as a result of better nutrition, sanitation, medical care, and improved overall standards of living. In reality, it is well-documented that this upward demographic transition ultimately leads to slower population growth and, eventually, stabilization or even population reduction.
Writing in 1771, thus before the industrial and post-industrial demographic transitions in Europe and North America, French economist Nicholas Baudeau argued that the “productiveness of nature and the industriousness of man are without known limits” because production “can increase indefinitely” and, as a result, “population numbers and well-being can go on advancing together.” A similarly optimistic but more recent perspective on human growth is economic geographer Peter J. Taylor’s analysis of the uniquely human ability to trade and innovate as a “release from proximity.”
Taylor’s remarkable 2013 book Extraordinary Cities examined the role of complex human settlements in driving human creativity and flourishing. “All animals, including humans, make use of their local environment through collecting, hunting, protecting, and organizing food and raw materials for reproduction,” he writes. “However, humans have added an additional way of making a living through exchanging goods…which can simply be the exchange of local food and raw materials themselves, or production derived from the food and raw materials.” Even prehistoric human societies, according to Taylor, show archaeological evidence of long-distance trade in goods. Thus, being able to trade for materials and foodstuffs from far away made humans the only species able to permanently transcend the limitations of their local environments.
The reign of optimism
The optimistic school holds that a larger population that engages in trade and the division of labour will deliver greater material abundance per capita. Population growth increases the size of the market and encourages specialization and economies of scale. These, in turn, engage an ever more granular and sophisticated division of labour. The result is that 100 people with 100 different skill sets who specialize in what they do best and who trade with each other will produce far more than 100 self-sufficient individuals engaged in subsistence.
In 1821 the French economist Jean-Baptiste Say harnessed this insight to challenge the belief that a reduction in population would “enable those which are left to enjoy a greater quantity of those commodities of which they are in want,” because it ignored the fact that a reduction of the workforce simultaneously destroyed the means of production. There is ample evidence that thinly populated countries do not tend to be the places where “the wants of the inhabitants are more easily satisfied.” On the contrary, it is the “abundance of productions, and not the scarcity of consumers, which procures a plentiful supply of whatever our necessities require.” This is why, he argued, more populous countries and metropolitan areas historically have been generally better supplied than their more sparsely populated counterparts.
Henry George similarly observed a few decades later that while one could see “many communities still increasing in population,” they were also “increasing their wealth still faster.” Indeed, “among communities of similar people in a similar stage of civilization,” the “most densely populated community is also the richest” and the evidence was overwhelming that “wealth is greatest where population is densest; that the production of wealth to a given amount of labour increases as population increases. These things are apparent wherever we turn our eyes.” In the end, the “richest countries are not those where nature is most prolific; but those where labour is most efficient – not Mexico, but Massachusetts; not Brazil, but England.”
Where nature is frugal, George added, “twenty men working together will…produce more than twenty times the wealth that one man can produce where nature is most bountiful.” This was because the “denser the population the more minute becomes the subdivision of labour, the greater the economies of production and distribution, and, hence, the very reverse of the Malthusian doctrine is true; and, within the limits in which we have reason to suppose increase would still go on, in any given state of civilization a greater number of people can produce a larger proportionate amount of wealth, and more fully supply their wants, than can a smaller number.”
Writing in 1803, Scottish agriculturalist James Anderson observed that human creativity could deliver increasing returns (i.e., when the output increases by a larger proportion than the increase in inputs during the production process) despite less valuable lands being brought under cultivation. “If these facts be admitted,” Anderson wrote, “it will follow, that by due attention to carry forward improvements in agriculture, the population of a country may be gradually increased to an indefinite degree, and the people still find abundant subsistence from the productions of their own fields, even where there seemed to be no superabundant produce at the time the population began to increase.”
A few decades later, a young Friedrich Engels (who had yet to co-author The Communist Manifesto) commented that the “productive power at mankind’s disposal is immeasurable” and the “productivity of the soil can be increased ad infinitum by the application of capital, labour and science.” At the dawn of the Twentieth Century British economist Edwin Cannan opined that while one might occasionally observe “diminution of returns,” these were typically only temporary until the development of “inventions and the introduction of better methods.” Indeed, the belief that “diminishing returns was the general rule throughout history” was “so contrary to the results of direct observation that it seems difficult to believe that it could ever have been accepted.” As a matter of fact, “no reasonable person can have any doubt that the productiveness of agricultural industry has enormously increased” and that “the population of the civilized world is much better fed, and yet has to spend far less a proportion of the whole of its labour on the acquisition of food.” If returns had actually diminished in agriculture, a “larger and ever larger proportion of the world’s labour would clearly have to be expended in producing food.”
As has been amply documented, agricultural yields in advanced and developing economies have increased dramatically over the last several decades. So has the amount of food per person while the amount of land under cultivation has only expanded marginally and the number of people directly engaged in agriculture has plummeted. Producers are supported by whole industries specializing in the production of agricultural inputs such as ever improving seeds, fertilizers and crop protection and by others who specialize in the marketing, processing and distribution of their commodities.
To give but one specific illustration, average corn yields in the United States have increased nearly six-fold since 1940 while the corn acreage has remained approximately the same, a feat that is made even more remarkable by the fact that nearly a third of the US corn crop is pointlessly diverted towards the production of ethanol. Thus, agriculture is feeding a growing human population in a more land-sparing and labour-efficient way with every passing decade.
One can muster at least two solid arguments in support of higher returns from greater population numbers. The first is that the more human brainpower is directed at problems, the greater the likelihood of beneficial inventions. As the British political economist William Petty observed over a century before Malthus first published his pessimistic Essay on the Principle of Population, it was “more likely that one ingenious curious man may rather be found out amongst 4,000,000 than 400 persons.” More recently, the physicist Robert Zubrin put it this way: which one of either Louis Pasteur or Thomas Edison should not have been born in order to improve the lot of humanity?
The second is the cumulative nature of technological development: the fact that present and future advances build on past ones. In a personal reply to and further face-to-face conversation with Malthus, the American diplomat Alexander Everett suggested in 1823 that an expanded division of labour not only made people more productive, but further laid the foundation for “the invention of new machines, an improvement of methods in all the departments of industry, and a rapid progress in the various branches of art and science,” resulting in improvements to labour productivity that far exceeded the proportional increase in population numbers. A belief in decreasing returns, he argued, ultimately assumed that “labor becomes less efficient and productive in proportion to the degree of skill with which it is applied; that a man can raise more weight by hand, than by the help of a lever, and see further with the naked eye than with the best telescope.” Needless to say, Everett’s observations have been verified in the computing and software industry via Moore’s Law, but similar – if not as spectacular – progress has been documented in all competitive sectors of market economies.
Engels similarly stood Malthus on his head by observing that “science increases at least as much as population. The latter increases in proportion to the size of the previous generation, science advances in proportion to the knowledge bequeathed to it by the previous generation, and thus under the most ordinary conditions also in a geometrical progression.”
In other words, the more that is invented, the more that can be invented because new ideas and technologies are created through their combination. And the more human brainpower is directed to tasks, the more new possibilities can be imagined.
As should be obvious to David Suzuki and the many people who share his preposterously gloomy outlook, overwrought biological metaphors and misinterpreted ecological concepts such as carrying capacity do not apply to human economic and population growth potential because of trade, innovation and the ongoing optimization of resource use driven by the powerful feedback system of the price mechanism. (In short, in a market economy characterized by freely determined prices and secured property rights, a rise in the price of a valuable resource has always only been temporary, as it provided incentives for people to look for more of it, to produce and use it more efficiently, and to develop substitutes.) The result is that, far from being stuck in the 59th minute, people overall have become more numerous, healthy and wealthy, as has been copiously documented, while resources have become more abundant than ever.
The Invisible Hand’s green thumb
Suzuki and his intellectual fellow travelers, however, have long maintained that humanity’s capacity to satisfy its demand for resources is unsustainable because nature cannot endure the pollution that inevitably accompanies a rise in human numbers and wealth. President Obama’s science czar, long-time eco-doom monger John Holdren, wrote nearly two decades ago that our problem is not “that we are running out of energy but that we are running out of environment, that is, running out of the capacity of air, water, soil, and biota to absorb, without intolerable consequences for human well-being, the impacts of energy extraction, transport, transformation, and use.”
There is plenty of evidence that the exact opposite is true. Most environmental indicators in the developed world have been improving for decades, from cleaner air and water to increased forestation. Higher standards of living give people the means and opportunity to attach increasing value to environmental amenities, which in turn leads to more stringent environmental standards, the development of pollution control technologies to meet these standards, and effective enforcement of these standards. Perhaps the most obvious example is water quality in advanced urbanized economies, which is vastly improved from the time when much smaller and poorer populations could not afford to build and operate sewage systems.
The biologist Paul Ehrlich famously opened his 1968 book The Population Bomb with a vivid description of the overpopulated and polluted conditions he had observed in New Delhi in 1966. With palpable distaste, Ehrlich asserted there were already too many people in New Delhi, with more to come. At the time, as journalist Charles Mann noted in a recent essay on Ehrlich’s work, the Indian capital had a population of approximately 2.8 million. Paris, by contrast, had a population of about 8 million. “No matter how carefully one searches through archives,” Mann sarcastically remarked, “it is not easy to find expressions of alarm about how the Champs-Élysées was ‘alive with people’. Instead, Paris in 1966 was an emblem of elegance and sophistication.” Only a few decades earlier, a much smaller and poorer Parisian population had faced a lethal pollution threat from horse urine and manure, a source of deadly diseases such as typhoid fever, yellow fever, cholera and diphtheria. Advances such as modern sewage systems and the internal combustion engine ultimately saved Parisians from these then-ubiquitous causes of urban morbidity – just as these and other advances have enabled the population of Delhi to grow to almost 19 million today.
Economic development also enables progressively less damaging ways to facilitate growth by increasing the efficiency of agriculture, resource extraction, manufacturing, transportation and communications. For instance, fuels and synthetic products derived from coal, petroleum and natural gas have drastically reduced human reliance on plants and animals. Examples of this substitution of concentrated underground resources for above-ground living matter include whales slaughtered for oil and perfume, and trees clear-cut for firewood, rubber, resin and dyes.
Modern environmentalists may dislike products derived from petroleum and natural gas liquids, but one can hardly deny that humanity’s increased reliance on resources extracted from below the earth’s surface not only helped preserve and promote life forms on the surface in various ways, but also provided humanity with a much larger pool of valuable resources than they could have created out of biomass.
Another virtue of the market economy ignored by the likes of Suzuki and Holdren is that it has long incented the creation of useful and lucrative by-products out of waste materials. In the words of Karl Marx: “With the advance of capitalist production the utilization of the excrements of production and consumption is extended” and the “so-called waste plays an important role in almost every industry” because finding new uses for previously unmarketable residuals ultimately increases “the rate of profit.” In Marx’s opinion, industrial waste recovery was “the second great branch of economy in the conditions of production” after economies of scale.
Nowhere were such waste-reducing processes more obviously displayed than in the meat packing industry. As the British technology journalist Peter Lund Simmonds observed in 1877, the waste of “the fifth quarter of the animal” was a question “that formerly used to be perpetually assailing Boards of Health, and other sanitary bodies who have the supervision of slaughter-houses, meat-markets, [etc].” By then, however, “the offal of cattle suited for food, the waste from dressing skins and preparing leather, and other animal refuse, all [had] their distinctive and remunerative uses.… and a source of evil [had become] the agent of much good, and the subject of a thriving and prosperous industry”.
The slag from iron furnaces (i.e., the stony residual matter separated from metals during the smelting or refining of ore) provides another interesting illustration. This waste matter prompted Victorians, after a few decades of experimentation, to adapt slag as a substitute for stone in concrete and for sand in cement mortar as well as an input in the manufacture of low quality glass, mineral wool and road asphalt. The British engineer John Kershaw described the major improvement that this brought to the British landscape: “Not only has this new manufacture solved the problem of slag disposal in Staffordshire, and in the other iron-producing districts of this country, but…the immense accumulations of slag, due to the past activities of the blast-furnaces, are being gradually removed, and the outward aspect of what in the past has been known as the ‘Black Country’ is undergoing a gradual change for the better, as a result of the success of this new manufacture.”
None of what these 19th and early 20th century innovators and optimizers described happened instantly, and many changes for the good – such as steps towards a more environmentally sustainable production – took decades to fully realize their benefits. There was undeniable environmental damage along the way, but it was always viewed as a problem to be solved, not a hopeless destiny. The dominant social narrative celebrated the increased efficiency, healthfulness and prosperity engendered by these economic and technological developments. Today’s narrative tends to focus on negative environmental outliers to the exclusion of success stories.
Economic stagnation is the real environmental menace
While it’s doubtful that most Canadian schoolchildren subjected to David Suzuki’s bacterial fear-mongering were offered counter-arguments, they could have undoubtedly benefitted from exposure to the work of another Canadian icon, urban theorist Jane Jacobs. As she observed in her 1969 book The Economy of Cities, humans are not “strictly limited in their numbers by natural resources” as they long ago stopped living like animals in the wild who use only a few resources and use them to exhaustion, without augmenting or ameliorating what they deplete. Once people embraced economic development by carrying out tasks more efficiently and by creating new things, Jacobs commented, they “began riding a tiger [they] dare not dismount, but [they] also began opening up new resources – unlimited resources except as they may be limited by economic stagnation…. Analogies of human population growth to animal population growth, based on the relation of population to current resources, are thus specious. The idea that, under sensible economic planning, population growth must be limited because natural resources are limited is profoundly reactionary. Indeed, that is not planning for economic development at all. It is planning for stagnation.” And stagnation, Jacobs added, is ultimately the real cause of pollution, poverty, and pessimism.
Far from benefitting humans and their environment, Suzuki’s reactionary Malthusian test tube claptrap is guaranteed to have negative impacts for humans and their environment. It is to good environmental stewardship what bloodletting or trepanning once was to medicine and, far from being inflicted on children, must be challenged and ultimately delegitimized.
Pierre Desrochers is an Associate Professor of Geography at the University of Toronto Mississauga. Joanna Szurmak is a doctoral student at York University’s Department of Science and Technology Studies. They are the co-authors of Population Bombed! Exploding the Link Between Overpopulation and Climate Change, from which this essay is partly derived.