A question: if you were asked to name the biggest general problem in the world today, what would you choose? Would it be climate change and extreme weather events? or general natural habitat destruction from economic development? or income inequality and poverty? or the threat of nuclear war? or the erosion of democracy in many countries? All of those are big problems and one could make a good case for any of them as the most serious problem facing humanity.
However, in mildly contrarian spirit, I would name something more abstract, a general problem in human (or at least Western) thinking. It consists of two flawed assumptions. The first is that most problems can be defined and compartmentalized from others, then treated as discrete entities. The second is that once a big problem has been solved, it is essentially gone forever; this is the idea of inexorable progress.1 If either assumption is false, then proposed political or governmental policy decisions to deal with the initial problem, whatever it was, will be inadequate. That inadequacy, in turn, guarantees the return of the problem while complacency about it having been solved means delay in dealing with its new aspect.
There are countless examples but let us take one from biology, discussed earlier in this series, bacterial infectious disease. In the past millenium, bacterial infections have killed many millions of people. The cumulative deaths from plague and cholera alone have done that. It was, therefore, with great relief that the era of antibiotics, starting in the 1940s, was hailed. For about three decades, antibiotics were believed to have ended the scourge of deadly bacterial disease. Yet the rise of antibiotic-resistant pathogenic bacteria has falsified the prediction of the end of bacterial infectious disease (see On wars, multi-drug resistance, and the globalization of risk of infection). Clearly, this problem had not been solved forever. This example also illustrates the connectedness of problems. We know that infectious disease continues to arise in conditions of poverty and lack of adequate sanitation. The eradication of such disease was never wholly a medical or biological problem; it was always tied up with social and political questions.
Such thoughts bring us to a problem that has always been with humanity: having enough food. This is not just a matter of survival but of having enough energy to do the things we want to do. For many people in Europe and North America, this no longer registers as much of a problem. If you are hungry, the solution is easy: go to your refrigerator or food cupboard! Or, with a bit more effort, go out to a restaurant. Problem solved!
But for most of human history, it was not so simple. Indeed, getting enough food was the central daily concern of most people for most of human history. Let us remember the time span embraced. Paleontologists take the age of our species, Homo sapiens, as about 300,000 years. In this period, until about 12,000 to 10,000 years ago, we were hunter-gatherers, living on plants we gathered and animals we hunted.
Our large brains helped us think about and solve the problems of food supply but also contributes to the problem. The average brain in the average adult human consists of about 2% of our body weight but consumes 20% of the energy we get from our food. Our physiology makes sure that, when food is short, the brain continues to get an outsize-share of the energy from that food to function well enough – after all, a working brain is essential for survival. Still, inadequate food supply leaves a shortage of energy for everything else and food becomes even more of a preoccupation.
What changed about 12,000 years ago was the end of the Pleistocene period, with its ice ages. This ushered in a period of greater global warmth, which permitted people to grow plants for their food supply. Thus, in a warmer world, agriculture became possible. With a growing range of plants cultivated and animal species domesticated, increasing numbers of people spent less and less time worrying about food. This in turn allowed civilization, in its different forms around the world, to develop. The fundamental change in daily life from our earlier hunter-gatherer state is this: most of us do not have to worry about where our next meal is coming from!
Yet, the subject of food sufficiency for humanity never disappeared and has periodically reared its frightening head. In the late 18th century, after the industrial revolution had begun in England and agriculture was well-established, this issue received attention from a perspicacious observer, an economist who was also a curate and a professor. Thomas Arthur Malthus (1766-1834) drew attention to what he saw as a major problem for the future in a book titled An Essay on the Principle of Population, published in 1798. There, he argued that food insufficiency was inevitable because food supply increases linearly while human population, especially of the poor, increases exponentially. It is a point that only someone with some mathematical inclination would come up with and Malthus, with his training in economics, was well suited to do so. An exponentially growing consumption of a resource that only increased linearly will inevitably produce shortages at some point. If the resource is food, that means that famines will occur.2
If Malthus was right, how soon might the catastrophe occur? One problem was that Malthus’ calculations were heavily dependent on various specific assumptions grounded in the specific realities of life in England. In particular, he neglected how death rates would impact the calculations and how average family size affected the predictions.
In retrospect, however, the major flaw in his thinking was his assumption that agricultural productivity would only increase at a steady arithmetic rate. There were, in fact, many improvements during the 19th century that dramatically increased both agricultural productivity and food delivery. Furthermore, the invention of artificial fertilizer from the Haber process in the early 20th century provided a massive increase in the amount of food that could be produced, not just vegetables and cereals for direct human consumption but grain for animal husbandry, allowing a massive expansion of animal farming and, as a result, meat production.
Hence, by the early 20th century, Malthus’ gloomy prediction was regarded as falsified. Food production had more than kept up with population growth. Yet, the voices of doubt and fear were not completely stilled. Human population had not only continued to grow exponentially but the numbers were beginning to be very large compared to earlier times. Around the time of Malthus’ book, the estimated human population was just under 1 billion people worldwide, having roughly doubled since a century earlier. By mid-20th century it was over two billion and by 1987 five billion. (We are now at slightly over 8 billion.)
A few solitary voices had been raised in warning that human population size might outrun food production capacity in the 1950s and 1960s. This line of thinking, however, received a massive boost in 1968 with the appearance of a book that put the matter center-stage. This was The Population Bomb by Paul and Anne Ehrlich, two biologists at Stanford University. They argued that the basic Malthusian contention was still valid and that the current data on food production and human population growth predicted massive famines from insufficient food supplies in the 1970s.
Fortunately, this prediction failed too. Why? Essentially because agriculture received a massive boost from the so called Green Revolution, which greatly allowed increases in agricultural productivity, not least in the countries of the Global South, who were experiencing the greatest population increases. The Green Revolution involved a host of new techniques (and new plant varieties) and it was spread out in time from the early 1940s to the late 1960s. It has been credited with saving two billion lives, a magnificent achievement.
Once again, the Malthusian catastrophe had been averted and, as before, this has been achieved by new technological advances. And yet, and yet…has Malthus’ prediction actually been disproved or was it simply premature? The basic and indeed simple mathematical fact that exponential population growth of any species on a finite planet cannot continue forever remains valid. Present estimates put human population growth peaking at 10-11 billion people (more than 10-fold that of Malthus’ time), which will be reached sometime in the second half of the 20th century, but that is still a huge number. Can food supply be maintained indefinitely for such large numbers?
This cannot be answered with any precision but it is worth thinking about now, to avoid any Malthusian catastrophe in the future. There are already indications that the whole system is fragile and, unless steps are taken to strengthen it, the worst outcome – major and widespread famines – might take place.
We may already be at the tipping point of experiencing them in certain war zones: Yemen, Sudan and Gaza. The situation, in terms of the numbers, is particularly dire in Sudan, where approximately 10 million people, out of 20 million, have been forcibly displaced and a large proportion of them are already experiencing severe food shortages. It is in the nature of such situations that the transition from a point of danger to one of catastrophe can happen fast.3 With famine, once it begins, it is already too late to prevent it from becoming massive.
It can be argued that such situations are political problems not ones of normal food supply and basic biology. Indeed, most famines since the mid-19th century, starting with the Irish potato famine, have had a large element of political causation. One sees this in famines that took place in Ukraine, India, and China. The Nobel Laureate economist, Amartya Sen, has emphasized this: famines today should not be regarded as unavoidable facts of life. Nevertheless, the current situations threatening human famines can be taken as “canary in the coalmine” situations. A world in which large scale famines can be triggered by political events is one in which food supplies are, clearly, already precarious.
That precarity is itself indicated by the ratio of food- (particularly) grain-supplying-countries to those who are dependent on those supplies. In 2022, nine countries were responsible for supplying 80% of the world’s most basic foods (wheat, rice, corn and soybeans) to 134 countries.4 The donor countries were: Australia, Argentina, Brazil, Canada, France, India, Russia, Ukraine, and the United States. This is not a secure situation. If something were to happen to agricultural production or steps involving the export of one or more of these foods to recipient countries that normally receive them, there would be serious consequences since other countries would not be able to step up immediately to make up the deficit. We saw this nearly happen in the war in Ukraine in 2022, when it looked as if Ukraine would not be able to deliver its wheat, with potentially dire consequences in Africa. The situation was saved by some deft diplomacy but it illustrates the fragility of the world’s food supply.
The world, fortunately, is neither in a Malthusian disaster nor facing an immediate prospect of one. Yet, climate change, in particular, has the potential for drastically reducing food supplies. It is not too soon for the world to start thinking about these risks and preparing for them. As with the Green Revolution, the solution will probably involve a smorgasbord of partial solutions, not one magic fix. We will return to this topic in a future article.
This optimistic view of human history was termed by the late influential evolutionary biologist, Stephen Jay Gould as the Whiggish view of history. That was in reference to the Whig Party of Great Britain who had this sunny view of things. It was flawed, of course, but in these darkening times, has a certain appeal.
Unlike the analyses of most economists, indeed most academics, Malthus’ book and prediction had a strong and early influence and his fame lives on. One of the people it most notably influenced was Charles Darwin, who realized that amongst living things, if a resource became scarce, there would be competition for it and some would fare better than others in obtaining it. Thus, Malthus’ idea was at the root of Darwin’s idea of natural selection as the motor of evolutionary change.
In a famous fictional dialogue in Ernest Hemingway’s The Sun Also Rises, one of the characters is asked how he went bankrupt and he replies to the effect, first gradually, then all at once. Many disasters have this character, in fact. Famines do too.
See the article, “Eating the Earth: the burgeoning global food trade is a lifeline for billions, but it is fragile and hard on the planet” by J. K. Bourne, Jr., Science 386: 956-967