The most powerful ideas, those whose influence radiates beyond the covers of books, inspire both fear and hope. Martin Luther’s claim that every man is a priest did so as did Marx’s conception of the revolution of the proletariat. Robert Malthus’ Theory of Population has this same ability to evoke both hope and fear. Since the day he launched it on July 13, 1798, a considerable portion of its influence can be understood by examining the ways it has engaged the hopes or fears of people and eras.
It was likely fated to do so from its inception. It was after all the product of an argument with his father. The elder Malthus, Daniel, was an enthusiastic proponent of the Enlightenment and its faith in boundless human progress. As such, he was beguiled by hope. Robert, the son, rebelled against paternal hope by devising a theory to prove that significant human progress is impossible. Unlike the history of most father/son disagreements, Robert devoted the rest of his life to refining his theory and searching out factual data to bolster it. He was transfixed by his sense of limits to human life and the fear they brought.
Robert Malthus’ initial formulation of his Theory of Population was both elegantly simple and mathematically precise:
I think I may fairly make two postulata.
First, that food is necessary to the existence of man.
Secondly, that the passion between the sexes is necessary and will remain nearly in its present state.
These two laws, ever since we have had any knowledge of mankind, appear to have been fixed laws of our nature, and, as we have not hitherto seen any alteration in them, we have no right to conclude that they will ever cease to be what they now are, without an immediate act of power in that Being who first arranged the system of the universe, and for the advantage of his creatures, still executes, according to fixed laws, all its various operations….
Assuming then my postulata as granted, I say, that the power of population is indefinitely greater than the power in the earth to produce subsistence for man. Population, when unchecked, increases in geometrical ratio. Subsistence increases only in an arithmetical ratio. A slight acquaintance with numbers will shew the immensity of the first power in comparison with the second.
In other terms, Malthus was claiming that farming practices can become more efficient or new lands can be opened for crop production, but the resulting increases in food supplies must be modest and incremental. Two human beings, however, may produce 4, 6, 8, or more offspring, each capable of producing another 4, 6, 8, or more children. In consequence, whatever gradual increase in food production humans achieve will soon be outstripped by the resultant increase in human population (assuming the passion between the sexes remains constant). Malthus believed that the relation between food production and population growth is modulated by two factors that he termed positive and preventative checks. Positive checks include starvation, war and disease, all means of reducing excess population. As far as Malthus was concerned, the only conscionable preventative checks were abstinence and delayed marriage. These are ways to avoid excess population. An Anglican clergyman, he ardently opposed birth control measures and sexual activity not intended to result in childbirth. So far as he was concerned, if individuals do not exercise the sexual restraint required by preventative checks, they are fated to suffer positive checks.
Though by all accounts among the kindest and gentlest of human beings, Malthus drew what he believed to be the inescapable conclusion of his Theory of Population: Food assistance to the poor is both futile and harmful. Because it eliminates a highly effective positive check on population increase, it is futile. Because food assistance will allow the poor to increase in number, it is harmful. In the initial formulations of his theory, Malthus appears to have assumed that impoverished people are incapable of exercising preventative checks. In other words, people too poor to feed themselves will flourish with the help of public provisions and naturally (he believed) produce more children. Their numbers will quickly increase and in time overwhelm the supply of food available to sustain them. As a result, future food shortages, when they inevitably recur, will cause greater suffering since a larger number of people will lack sufficient nourishment.
In light of this, young Robert declared that the British Poor Laws of his day should be scrapped and, after a decent interval, public assistance to the poor should cease. Malthus understood that some individuals and their children would likely starve as a result, but he concluded that their miserable fates would be the just consequence of their own ill-advised choices. As he puts it:
If any man chose to marry, without a prospect of being able to support a family, he should have the most perfect liberty so to do. Though to marry, in this case, is, in my opinion, clearly an immoral act, yet it is not one which society can justly take upon itself to prevent or punish; because the punishment provided for it by the laws of nature falls directly and most severely upon the individual who commits the act.
Several of Malthus’ assumptions are worthy of notice. First, though it would be unfair to claim Malthus believed human beings are simply organisms that transform food into babies, that crude formulation seems uncomfortably near his position. He does not provide an analysis of the factors that he believed propel humans to reproduce (apart from the passion between the sexes), but he did seem to presume that they generally will do so if they are able. As far as he was able to discern in 1798, humans would cease to reproduce only when they became sufficiently miserable. Nonetheless, his Theory of Population mentions only the passion between the sexes. “Passion” appears to refer simply to the desire for sexual relations not the desire to conceive children. Because of his religious beliefs, Malthus does not at this point consider the possibility of birth control or the possibility that people may be glad to have sexual relations without the prospect of reproduction. Nonetheless, these latter possibilities eventually became a rallying cry for activists, John Stuart Mill among them, who sought to escape the implications of the Malthusian dilemma by distributing information on birth control. Among history’s ironies, Mill and others who endorsed methods of birth control, came to be known as ‘Malthusians’ even though Malthus himself deplored such measures.
Second, one of his more notorious assumptions is that the reproducing poor, since they cannot feed themselves, are responsible for the plight of any children they produce and must therefore suffer the consequences of their actions. Once again, the foundation of Malthus’ thinking is difficult to make out. The poor lack sufficient resources to feed themselves. That is true by definition. Malthus assumed without question that people who bring children into the world have sole responsibility to feed them. His critics were quick to deplore this element of his thinking. Nonetheless, this facet of his thought also attracted later followers, the neo-Malthusians. At least one of the neo-Malthusians, Garrett Hardin, does not hold the view that the poor are responsible for their plight. In Hardin’s view, their suffering is simply a matter of bad luck for them, but the price of excess human population is most naturally born by the poor. That is particularly the case since food aid will allow them to reproduce and thus exacerbate a difficult situation.
Third, Malthus believed that hopes for social progress are doomed on grounds there can never be sufficient food to provide a comfortable existence for all members of a society. Though he allows that chastity may serve as a preventative check on overpopulation, he appears to lack much confidence in its efficacy. He assumed, recall, that the passion between the sexes is an extraordinarily powerful force. Nearly a century after he initially formulated his theory, this implication was spelled out vividly by Darwin’s Bulldog, Thomas Huxley. Huxley asks us to imagine a perfect society, one in which all would be comfortable, justly treated, and competently governed. He claims such an ideal society cannot endure, no matter how brilliantly and compassionately it is governed because those comfortable folk will naturally reproduce. The resulting population surge will upend the fragile balance between population and resources and thus destroy the well-ordered society. These shortages will cause Huxley’s Edenic society to collapse into a dog-eat-dog war of all against all. Though Huxley’s schema lacks Malthus’ nuance, its outline is similar to what Malthus envisaged, and it embodies the perspective that motivates those who fixate on fear. It is easy to understand why Thomas Carlyle was moved to label Malthus’ views “dismal.”
As we might imagine, the responses to Malthus’ theory were immediate, varied, and impassioned. His critics were largely animated by hope, the confidence that his dire predictions could be evaded through human resourcefulness or elimination of social injustice. The legions of Romantics, those in rebellion against Enlightenment rationalism, were motivated in this way and were among the first to take offense at Malthus’ theory. The Romantics, including
Wadsworth, Coleridge, Shelly, and Blake, had several complaints. First, being Romantics, they were repelled by Malthus’ devotion to reasoned analysis and his enthusiasm for factual information. As Robert Mayhew puts the matter, “Those we label as ‘romantics’ shared, almost without exception, a hostility toward the dictates of calculation and political economy.” They lived amid the Industrial Revolution and were dismayed by the ways in which it reshaped human life. In response, they were convinced that the solution to whatever problems beset humanity is to cast reason and careful analysis aside in favor of unrestrained natural impulse. Were that to occur, they were confident that the shortages and suffering Malthus envisaged would disappear without conscious effort. But, second and closely related to the above conviction, they asserted that Malthus did not give sufficient weight to human creativity, which they believed is also achieved by setting aside rationality and self-control. They presumed that there is no upper limit to the resources human invention is capable of providing to sustain human life. Third, the romantics were particularly upset by Malthus’ conviction that poor people should bear the burden of adjusting human population to fit available food. Last and closely related to their irritation at the view that the poor should bear the burden of winnowing excess population, they were convinced that the fundamental difficulty with human food supplies is found in the way human resources are distributed rather than their scarcity. As Mayhew puts it,
For Wordsworth, ‘oppression’ was not the product of nature as it was for Malthus, but was instead the consequence of how,
“Society has parted man from man,
Neglectful of the universal heart.”
Indeed, not only did the work of Malthus and the political economists misunderstand the cause of poverty, ascribing to nature what was the work of mankind, they by their very forms of argumentation created the breeding grounds of poverty…
The Romantics were adamant that, if human resources were distributed more equitably, there would be no shortage of food and thus no hunger.
Marx and the socialists were as vehement and hopeful as the Romantics, for they were convinced that a socialist utopia can be achieved under appropriate circumstances. Along with the Romantics, Marx argued that poverty and starvation resulted from private ownership of property. Property ownership allows a small minority to amass enormous stocks of a society’s goods and leave most humans with few or no means to support their lives. Were private ownership eliminated and control of property granted collectively to all humans, each individual could easily gain sufficient resources to support a decent existence. This hope fueled the Marxist ire at Malthus’ predictions of doom. Food shortages, they believed, are simply the result of inequitable distribution of human resources and the greed of those who control of the means of production.
Nonetheless, it is entirely likely as many were attracted to Malthus’ arguments as were revolted by them. A key attraction for many of the fearful was Malthus’ emphasis on limits, the limits set for human populations by the earth’s resources. That conception works beautifully in some contexts. For example, Malthus’ Theory of Population directly inspired Darwin to construct his theory of natural selection. As Darwin puts the matter:
In October 1838, that is, fifteen months after I had begun my systematic inquiry, I happened to read for amusement [??] Malthus on Population, and being well prepared to appreciate the struggle for existence which everywhere goes on from long-continued observation of the habits of animals and plants, it at once struck me that under these circumstances favourable variations would tend to be preserved, and unfavourable ones to be destroyed. The result of this would be the formation of new species. Here, then, I had at last got a theory by which to work.
The subsequent influence of Darwin’s theory is ample testimony to the felicity of his inspiration. But, if Malthus’ theory works so wonderfully for understanding the domains of life Darwin examined, why has it thus far failed to establish limits to human population? Malthus’ distinction between positive and preventative checks holds a portion of the answer. Though there are important exceptions, animals are for the most part subject to positive checks alone. Humans, on the other hand, may employ preventative checks as well.
Malthus was convinced that in 1798 the human population had surpassed the limit of the earth’s ability to support it. The human population in Malthus’ era was approximately 1 billion. The irony is that the human population of the earth began to shoot up after 1800 and now exceeds 7 billion. Yet, there is no evidence human misery has increased in the past two centuries or that we have come nearer the boundary of the earth’s ability to support humanity. As a matter of fact, more people live more comfortably at the present time than during Malthus’ day. The number of people living in absolute poverty has declined markedly in recent decades and human life expectancy has steadily increased. Furthermore, some commentators argue that membership in the middle class is steadily increasing and now encompasses more than half the human population. Hence, another part of the explanation for human success is that the history of the past 200 years gives vindication to the Romantic conviction that human resourcefulness is sufficient to avoid Malthus’ dire predictions.
The neo-Malthusian, Garrett Hardin, writing in the 1960’s, also assumed that the human population of his day had outstripped the limit of the earth’s capacity to support human life. During that period, the earth held perhaps 4 billion people. As noted earlier, the world’s population has lately surged past 7 billion, and there is as yet no sign that the earth’s ability to support human life is stretched to the breaking point. To the contrary, human life expectancy continues to increase, and the number of people in dire poverty continues to decrease. Along the way, there has been a subtle but important shift in Malthusian thinking. The revised position is that there must be some ultimate limit to the earth’s ability to support human life. Since no more land, earth, or atmosphere are being created, that stern view must at some point be correct. As it happens, commentators have noted that humanity’s increasing wealth is likely to hasten the juncture at which that limit is reached. That is because wealthier humans use more energy, generate more pollution, and consume more food than impoverished masses. Nonetheless, it is by no means clear when the limit to human numbers is likely to be surpassed, and it is unlikely it will be surpassed soon. And so, the conflict between the hopeful and the fearful continues. The history of the past two centuries provides support for the hopeful. It nonetheless is difficult to avoid the conclusion that at some point the fearful will gain vindication for their view.
Robert Mayhew is a resourceful and sympathetic commentator who is convinced history has not given Malthus his due. He notes (correctly) that the participants in the 200 odd years of debate between hopeful and fearful commentators show little sign they have actually read Malthus’ work or recognize the way he developed and refined his thinking throughout his life. From this perspective, Mayhew makes the case that Malthus also appeals to a more sober and tranquil domain of human psychology, that of reason. He invites us to step back from Malthus’ Theory of Population and attend to his recognition of the ways that the parameters of human population, natural resources, and public policy react on one another. Mayhew is able to cite a number of prominent thinkers, John Maynard Keynes among them, who were pleased to employ this analytic strand of Malthus’ thinking.
That is entirely reasonable. Malthus’ mode of analysis is both useful and astute. Nonetheless, the early, rash formulation of Malthus’ Principle of Population is the version that has fired imaginations from Malthus’ day to ours and propels his name to headlines again and again. Mayhew concludes his study without making a judgment of whether Malthus’ theory is right or wrong. Instead, he opens himself a graceful exit by noting the claim that a truly great intellectual achievement seems always contemporary, and he asserts that is true of Malthus’ Principle of Population. He supports this conclusion by citing the frequency with which Malthus springs back into public consciousness. However, Mayhew doesn’t note that Malthus returns to the focus of conversation during those periods when people have reason to be concerned about the limits of the earth’s resources. Whatever subtlety, ingenuity, or insight Malthus’ later work displays, it is fear and hope that propels his thinking back into public consciousness.
Nonetheless, the neo-Malthusian conviction that there is some upper limit to the ability of the earth to support its human population must be correct—even if we have no inkling of whether that limit may be reached decades or centuries in the future. As it happens, Peter Singer addressed this matter some decades ago. When he did, he found a way to accommodate both hope and fear. A utilitarian, Singer accepts Garrett Hardin’s claim that there must be some ultimate limit to the earth’s ability to support its human population. Singer also agrees with Hardin’s conclusion that, if that limit is exceeded, it will be necessary to allow excess human beings to die. He is thus attuned to those who are fearful. However, Singer also notes, writing in the early 1970’s, that the earth had not reached the state of population crisis and was unlikely to do so for the decades to come. During that interval, he believes there are clear alternatives to Malthus and Hardin’s grim policy of letting excess humans die. And so Singer finds ground for hope.
Singer mentions two options: use of birth control and what has come to be known as the Benign Demographic Transition. As it happens, there is a link between Singer’s two options. The Benign Demographic Transition is the idea that the fertility rate for women declines as income levels increase. Typically, the fertility rate of wealthy nations reaches a plateau ranging somewhere between 1 and 2 children per woman. As an average fertility of 2.1 is necessary for a stable population, the population of several developed nations is declining. Hence, the most economically advanced nations in the world commonly have low birthrates and often have declining populations. And, the most impoverished nations have the highest fertility rates and increasing populations. The connection to birth control measures is obvious. Women in wealthy nations employ birth control measures to control fertility, but women in impoverished nations often do not or cannot do so. Furthermore, there is a distinct inflection point at a per capita income of $5,000 in 2004 dollars. Fertility shoots up below that level and declines above it. In consequence, Singer concluded that there is ample time to use other measures to curb human population growth before resorting to the draconian measure of allowing people to die.
The decades following Singer’s article provide ample support for his analysis. Global fertility rates for women have steadily fallen since the 1970s. But, human prosperity has increased even as the human population has continued to soar. Though predicting future population levels is notoriously difficult and uncertain (the estimates of the 1970’s have proven wildly wrong), there are grounds to believe the current declines in fertility will continue. According to United Nation’s analysts, three factors influence fertility in women. The 1st is the extent of urbanization. As of this writing, more human beings live in cities than rural areas. Urban residents have excellent reasons for seeking fewer children than those in rural areas. They have less space. They commonly need to pay to educate their children. Child labor is often illegal and returns limited income to families. The 2nd factor is the extent of education for women. As women become more highly educated, they tend to have fewer children. Current data show that the education level of women is steadily increasing, even in war-beset Afghanistan. The final factor is the extent of women’s economic activity. Again, it is increasingly common for women to work outside the home. In several nations, and the United States is a prominent example, it has become the norm for women to hold employment outside the home. Obviously, education and economic activity are closely linked. Greater education allows more opportunity for women to become economically active and thus enjoy greater control over their own lives. Each of the above factors has increased considerably in recent years, and each appears likely to continue to increase. Hence, barring radical and unexpected change, fertility is likely to continue its steady decline of the past several decades. The United Nations currently estimates that the world human population in 2050 will reach 9.7 billion then attain 11.2 billion by 2100. As there is no catastrophic shortage of the world’s resources at the present time, Singer’s hope for a humane resolution of global human population seems amply justified.
Nonetheless, there are perils and limits that neither Malthus, Hardin, nor Singer foresaw. In the present era, the major threats to global human health and wellbeing include the intertwined factors of environmental pollution and global warming, and Malthusian thinking should be revised to account for these perils. Both are apt to cause difficulty for all humans and not simply the poor. It happens that the wealthy are better situated to escape the most harmful effects of each, but they will suffer from air pollution and energy shortages along with the rest. However, the above threats do not result simply from increasing human numbers. Rather, they are the products of changes in the ways human beings live.
Environmental pollution and global warming are prominent consequences of increasing wealth and the desire of people with rising incomes to lead the sorts of lives enjoyed by the wealthy people of the world. Among other things, that prosperous way of life requires enormous quantities of energy with its resultant contributions to global warming and environmental pollution. Economic advance requires energy, and the mode of life enjoyed by prosperous people in wealthy nations requires yet more energy. Furthermore, as their incomes increase, people want automobiles and the diets of wealthy Europeans. So, they burn more petroleum, eat more meat and consume larger amounts of processed foods, all of which require greater resources and more energy than traditional foods. In light of these factors, Malthusian thinking must be revised in a second way. Human numbers are not the problem. The problem is that the ways of life of the prosperous pollute the environment and exploit natural resources in ways that propel us closer to the limit of the earth’s capacity to support life. And this implies a 3rd shift in Malthusian thinking. It is no longer plausible to assert that poor people generate greatest pressure on the earth’s resources and establish the boundaries of human numbers. Rather, wealthy people and their ways of life are moving us closer to the limit of the earth’s ability to support life.
Once again, hope and fear can be addressed in Singer’s fashion without consigning enormous numbers of people to misery or death. Many people around the world are concerned by these dangers and are working out ways to address them without sacrificing human lives or causing significant degradation in the quality of life they enjoy. If humanity dawdles long enough, it is certainly possible that drastic or draconian measures will be required. However, as Singer would no doubt insist, we have not yet reached that point. Without reference to Malthus, Pope Francis appears to have reached this same conclusion. In his recent encyclical on the environment, he concludes that the poor are the victims rather than the causes of environmental threats. The core problem, he asserts, is the greed of the wealthy.
Malthus performed useful service to humanity by focusing its attention on limits. However, at this juncture, his convictions that expanding human population was the major problem and that the poor should bear the brunt of addressing population excess appear misplaced. At the present time, the most fundamental limits to human life are those posed by the linked threats of climate change and environmental pollution. Both trends are largely propelled by the modes of life of the wealthy or the rapidly prospering. Hence, if there is a price to be paid to address their threat, it is most reasonably paid by the comfortable rather than by the afflicted. Should Robert Mayhew elect to issue an updated edition of his study of Malthus, he may well find it appropriate to revise his conclusions in light of the above. That said, Mayhew’s core insight that Malthus’ mode of analysis is his most enduring contribution to human understanding remains unscathed.