The (Newest) Population Problem

The question many young adults are asking themselves today—and the central question of this two-part essay—is: “How can we think of having children, given what we know about the climate crisis?” As Ezra Klein notes, there are at least two questions present here. The first is about culpability: “Should I have kids, knowing they will contribute to the climate crisis?” And the second is about suffering: “Should I have kids, given the climate crisis they will face?”

In this first part of the essay, I trace the historical emergence of the first question—of ethical calculations concerning childbearing, resource scarcity, and environmental degradation—and map some of the ways that modernity’s moral calculus has tended to answer this question. (Spoiler: it’s not all doom and gloom.) In the second part, I turn to the latter question about human suffering. My goal is to explore how it was that a method of pseudo-utilitarian calculation became the default response to our deepest moral questions about what makes a life worth living. Across these articles, I want to suggest that the attempt to calculate the value of a single human life is a misguided project, and (in the second part) to show how the dystopian film Children of Men (2006) offers an alternative response to questions about suffering and social responsibility. 

In 1798, the Anglican parson Thomas Robert Malthus published An Essay on the Principle of Population, a conservative’s response to the utopian strain of Jean-Jacques Rousseau, Nicolas de Condorcet, and others who dominated the political and philosophical discourse of his day. Malthus’s argument began, simply and elegantly, from “two postulata”: “First, That food is necessary to the existence of man. Secondly, That the passion between the sexes is necessary.” Since “subsistence” increases at an “arithmetical ratio” (1, 2, 3, 4, 5) and population increases at a “geometrical ratio” (1, 2, 4, 8, 16), Malthus concluded “the power of population is indefinitely greater than the power in the earth to produce subsistence for man.” Consequently, subsistence was a “strong and constantly operating check” on population, one which rendered the utopian aspirations of Rousseau and Condorcet nil. Given any case where enough subsistence is gathered to overcome poverty, this very abundance will inevitably produce a population that outstrips the land’s resources, plunging a portion of the population back into poverty. Thus, in a deft move of rhetorical judo, Malthus defeated the utopian thinkers at their own game: he conceded that utopia was possible, but demonstrated how it was doomed to buckle under its own weight.

Malthus’s theory led him to advance a set of policy recommendations (his notorious claim that the English “Poor Laws” produced poverty) and to entertain some curious moral theological implications. The vicious cycle, Malthus realized, required a theodicy in which “moral evil” is understood to be “absolutely necessary to the production of moral excellence.” The inevitability of human suffering was not a problem since it was endowed by God with divine meaning and purpose; it “awaken[ed] social sympathy” and “generate[d] all the Christian virtues.” This disposition meant that Malthus had no concrete counsels on the question of childbearing, since humanity, no matter how vast or tiny, will never escape its population problem.

In contrast, proponents of neo-Malthusianism—a school of interpretation popular since the 1960s—do not mince words on the subject childbearing. In The Population Bomb (1968), Stanford Professor emeritus Paul Ehrlich rehearses Malthus’s fatal trap of population and subsistence but begs readers not to have children. Erlich replaces Malthus’s philosophical conservatism and theodicy with visions of the apocalypse—mass starvation, plague, thermonuclear war—all because humans (especially Indians and Roman Catholics) refuse to decrease their birth rates. Unlike Malthus, Erlich trusts that rationality could overcome even the deepest emotional and biological drives: “with a rational atmosphere mankind should be able to work out the problems of de-emphasizing the reproductive role of sex,” particularly the “ego satisfaction” that accompanies parenthood.

This is a thin account of parenthood, rationality, and sexuality, but it is not the gravest error of Erlich’s book. Like Malthus, Erlich undersells the human capacity for change. Reading the 1968 edition today, one cannot help but chuckle at Erlich’s bleak assessments of his era’s emerging agricultural technologies, a period of innovation scientists now refer to as the “Green Revolution.” I don’t mean to dismiss Erlich outright. His claim that controlling population growth is the only way to avoid a global food shortage is a crucial precursor to the (now ubiquitous) argument that controlling population growth will mitigate climate change—what we might call “Climate Malthusianism.”

But Erlich’s technological pessimism registers why William MacAskill’s What We Owe the Future (2022) is such an important intervention in this conversation about population and environmental degradation. MacAskill's book theorizes and defends “Longtermism”: “the idea that positively influencing the longterm[sic] future is a key moral priority of our time.” The introduction, a reflection on how many people have existed, do exist, and could exist, evokes awe in the reader. We learn that one hundred billion people have existed; eight billion people currently exist; and “if humanity lasts only as long as the typical mammalian species (one million years), and even if the world population falls to a tenth of its current size,” then around 99.5 percent of people—more than twenty trillion human beings—have yet to exist. MacAskill’s appreciation for the enormity of potential human life is matched by a hard-won optimism about the kind of world we could pass on to these “silent billions.” I want to praise MacAskill’s optimism but critique his methodology, which, while I admire the results it yields, continues the basic pattern of thinking from Malthus and Erlich.

MacAskill’s optimism is hard-won because his Longtermism, unlike Climate Malthusianism, takes into account the question of growth. On one hand, there are the risks associated with climate change (rising sea levels, increasingly dangerous and costly weather events). On the other hand, there are the risks associated with stagnation (no technological advancement means runaway climate change, barring the unlikely scenario that all humans return to pre-industrial lifestyles). We are caught, once again, in a double bind: more people means more emissions, but surmounting stagnation requires more people. This is because technological progress gets more difficult as more advances are made: “every doubling of technological advancement takes roughly four times more research effort,” so to combat climate change, we need more people to pursue careers in research and development—which means, of course, that we need more people. As MacAskill writes, “civilisation’s technological advance is like a climber scaling a sheer cliff face.” Once you start climbing, you can’t turn back. And if you don’t keep climbing, you will soon fatigue.

By adding the variable of growth to the climate and population question, MacAskill coaxes his readers to precisely the opposite conclusion of Erlich and his ilk. Thus the Climate Malthusians could be wrong for the same reason that Erlich was wrong about a global food shortage—both discount human ingenuity, which is amplified when there are more humans. But it is striking that the approaches to human life in Erlich and MacAskill are almost identical. “Are more people better for the world?” and “Are more people worse for the world?” turn out to be two versions of the same question, since both presuppose an account of human beings as instrumental, valued for what they produce (MacAskill) or consume (Erlich). Today’s Longtermists and Climate Malthusians, ostensibly at odds, in fact belong to the same genealogy of modern thought.

Weighing these theories, it remains a guessing game as to how population growth will contribute to climate change. The next generation of children are as likely to be a part of the problem (Erlich) as they are to be a part of the solution (MacAskill). The more urgent question, then, is the second one: “Should I have kids, given the climate crisis they will face?” In the second part of this essay, I will consider MacAskill’s approach to human suffering in light of Alfonso Cuarón’s Children of Men, a movie that takes us to the edge of the rational and calculable. 

Anthony Shoplik is a PhD candidate in the English Department at Loyola University Chicago. His current research explores the confluence of U.S. environmentalism and conservationism with American accounts of national and racial identity.