6

The Problem of the Future

IN THE FACE of the crises of the 1970s, many political philosophers tried to extend the Rawlsian rules across time as well as space, into the future as well as across the globe. The future seemed suddenly uncertain. By 1970, economic growth had stalled. Some economists began to wonder whether it was “obsolete.”¹ With rising unemployment and inflation, fear mounted, particularly in Britain, about long-term “declinism.”² There was panic about the governability of democracies and the legitimacy of the state.³ But the legitimacy crisis worried philosophers less than it might have: given the centrality to liberal egalitarianism of a belief in shared values at the core of society, the idea that democratic states might no longer be able to deliver the goods that made those values possible was perhaps too large, and too threatening, a problem to contemplate. Another crisis instead caught their attention—the environmental one, which fused anxieties about population growth and resource depletion with attacks on the “growthmania” of postwar liberalism.⁴ After the publication of Paul and Anne Ehrlich’s The Population Bomb in 1968, racist and racialized worries about overpopulation reached fever pitch.⁵ By 1970, the book had gone through twenty-two printings, and by 1974 it had sold over two million copies.⁶ The Ecologist published its “Blueprint for Survival” in 1972, the same year that the Club of Rome released The Limits to Growth report, which forecast that growth amid finite resources would lead to “overshoot and collapse.”⁷ Four million copies were printed, in thirty languages.⁸ The problem of the earth’s survival became mainstream.⁹ Models of alternative futures proliferated, from economic theories of “steady” or “stationary” states to scenarios of “zero population growth” and prophecies of mass starvation and famine.¹⁰ Environmentalists became apocalyptic.¹¹

These anxieties lie at the forgotten origins of liberal political philosophy’s turn to the future. Philosophers responded to the declarations of crisis and demands for an “ecological ethic” and “new ethic for survival” by extending moral theories to cover relationships with the natural world and nonhuman animals. Some began to defend animal rights.¹² Peter Singer provided a utilitarian defense of animals in Animal Liberation (1975).¹³ Others founded journals like Environmental Ethics. But many also explored how to value the future—and how to accommodate our moral relations to it—within the framework of the new liberal philosophy. Rawls’s theory reflected the era in which it was built: it was underpinned by assumptions about growth, affluence, and stability that shared the optimistic temporality of postwar liberalism and was common to macroeconomics, theories of modernization and post-industrial society, and even the “futurology” boom.¹⁴ Rawls had borrowed from some of these. Now they all seemed to be coming apart. From the late 1960s into the 1980s, moral and political philosophers looked to theories that might do better with the challenges of the new age. They extended legal and political accounts of obligation to explain why the living should care about future generations. What obligations did the present generation have to its successors? Were there individual duties to save and invest for the future, or to not have children? Out of these debates, intergenerational justice theory was born.

In the early 1970s, many philosophers extended the methods of applied ethics adopted during the Vietnam War to cover emergency life and death situations beyond war. The threats of famine and overpopulation were preoccupying. “Intuition pumps” like the trolley problem proliferated as increasing numbers of moral and political philosophers tried to address the ethical dilemmas raised by the neo-Malthusian diagnoses of the international situation. It was in debates about the future existence of the world that these philosophical methods were consolidated. So was a particular aspect of the new approach to public affairs: philosophers now looked to test general principles about the nature of morality and personhood on hard cases. Yet the problem of population also generated novel philosophical puzzles, most famously those theorized by Derek Parfit. A distinct relationship between contemporary dilemmas and their philosophical resolutions began to take hold as complex moral questions were detached from continuing political controversies. With problems of the future deinstitutionalized, moral philosophy went to a new realm of abstraction. The racist and civilizational discourse of overpopulation would gradually become politically toxic for liberals and the left as antiracist critiques of eugenics, sterilization, and population control gained traction.¹⁵ But it was philosophically durable. Overpopulation and ecological survival became problems for the moralist and metaphysician. Liberal philosophers mastered the art of turning an ethical crisis into an anodyne puzzle.

At the same time, others tried to accommodate these dilemmas of the future within justice theory by looking to the technical instruments of economic theory to make the future present. Some worried that thinking in terms of the earth threatened to undermine the Rawlsian framework—and, potentially, the core assumptions of humanitarian ethics more broadly. An ecological perspective might support the move to an ethics of the global, beyond Rawls’s bordered theory. But it also undercut it. For just as the international ethicists’ vision of a global moral community was shot through with political and historical differences, there were also drastic disagreements over what the present should sacrifice in the name of the future. “Survivalist” discourses of scarcity scenarios and conflicts over population size threatened to undermine the terms of justice theory, as well as the assumptions on which liberal egalitarianism rested. Moreover, the very category of the individual moral person, which philosophers valued so highly, now came under pressure—not because of a new interest in animals and the earth, but because of controversial philosophical ideas that issued from the overpopulation debates.

Could justice theory survive survivalism? As moral and political philosophers responded to a new set of preoccupations, it sometimes seemed like the Rawlsian paradigm would be unable to accommodate them. Ultimately, it did. Countervailing ideas were absorbed. By the close of the decade, another plank of the Rawlsian framework—intergenerational justice theory—was in place. For the most part, liberal egalitarians avoided debate about the legitimacy crisis, which might have threatened philosophical liberalism in the same way it did political liberalism. Instead, they responded to the environmental emergencies with new moral theories. In the end, these proved the resilience of the new philosophy of public affairs. For even where new ideas cut against the core tenets of liberal egalitarianism, they helped to shore up something more fundamental: a view of philosophy, underpinned by a commitment to a general, impartial morality, which abstracted from political problems in order to solve them.

When Rawls was piecing together his theory, he made clear that the future raised conceptual challenges. Back when he had conceived of society as a game, he had viewed certain related concerns as outside the game’s normal course of play: the “conservation of resources” and “future generations” could not be left up to the vicissitudes of luck and competition.¹⁶ Within the history of political thought, this challenge of incorporating the demands of the future was familiar.¹⁷ Political philosophers had long been concerned with how ties of sentiment, self-interest, or community could extend through time. Theories that relied on self-interest conventionally gave little value to the future, while conservatives or communitarians extended the duties of the living far across temporal lines. Democrats tended to view present decisions as unable to bind those of the future: what mattered was the collective decision, the aggregated subjective preferences of the living, the sovereign people. The more radical the democrats, the more presentist their temporal view.¹⁸ Many also recognized that the future required particular kinds of institutions. Insurance, wills, credit, the modern state itself, were all devices designed to work for the future. State theorists imagined artificial corporate persons, whose existence outlasted the lives of the natural persons who formed their constituent parts, as necessary to bequeath security to remote posterity.¹⁹ By the 1970s, philosophers had abandoned this approach. An “eternal moral person” of the state was no longer viable, Peter Laslett declared: “What is wanted is a relationship between generations which is individual as well as social, and passes through mortal individuals rather than through deathless collectivities.”²⁰

In twentieth-century political thought about the future, the main dividing line when it came to institutions was between those who supported planning and the attempt to command the future and those who rejected planning in the name of the market or individual freedom. In the early Cold War, the importance of leaving individual futures open became a feature of defenses of liberalism and capitalism: where neoliberals and social liberals disagreed was about how much and what kind of institutional intervention was required to secure the conditions of an open future.²¹ These concerns permeated postwar thought at various levels. A philosopher like Stuart Hampshire condemned any vision of social life, notably utilitarianism, that prevented individuals from acting in the world as future-oriented “active experimenters.”²² For liberal economists, what mattered was individual control over an open future, whether it was achieved through the actions of calculating men who were no longer mere “partners in exchange” but “entrepreneurs” of themselves or through social mechanisms to tame uncertainty and manage risk.²³ After moral and psychological approaches were displaced in postwar neoclassical economics, microeconomic theories of decision-making, like subjective expected utility theory, became the dominant, formalized approach to theorizing the future. Models of decisions under conditions of risk and quantifiable uncertainty were stretched to cover choices between future distributions, investments, and social systems as well as to study conflict.²⁴ These tendencies to individualize and formalize expectations about the future would be extended when the critique of Keynesian and macroeconomic ideas represented by the “rational expectations” revolution and efficient markets hypothesis made fully informed individual choices and predictions of future events the “microfoundations” of economic theory.²⁵

Rawls adapted many liberal economic ideas. He shared with the neoclassical orientation toward expectations and choices a downgrading of historical arguments. He wanted individuals to have sufficient goods to pursue their “life plans.” What they did with those goods was up to them. At the level of the choice of society—of what system would best facilitate that pursuit—Rawls argued that the parties in the original position would want to protect themselves against bad future outcomes. When faced with uncertainty, they would insure against natural and social misfortune. In that sense, they were not entrepreneurs. They made institutional plans to take care of the future. Nor did Rawls endow his choosing persons with total information, but restricted knowledge.²⁶ Yet Rawls did see the problems of the future, conceived of as a discrete object, as having a peculiar political status. Were obligations to future generations distinct from other obligations? And were these obligations a matter of justice? Rawls’s theory was a contract theory, and contracts with the future were hard to envisage. International justice theorists had found making distant people the subjects of contract theory hard enough. Making contracts with future people who did not yet exist was harder still. In Rawls’s case, the contract turned on the existence of a practice—a cooperative scheme characterized by reciprocity. Given the radically nonreciprocal relationship between present and future, how could contractual relations hold across time?

Rawls thought a reciprocal relationship with the future was impossible, and his principles of justice did not apply to it. Aspects of the relations with the future were still a “matter of justice,” but the interests of the future in general were outside the normal play of the social game.²⁷ Most considerations about the future were supplementary to the principles. They were to be seen as a part of obligations in the present, the “natural duty” to uphold just institutions. Rawls’s main argument was the “just savings principle,” which qualified the application of his principles of justice.²⁸ This principle circumscribed relations between generations by setting an appropriate savings rate and constraining the accumulation rate, so that the actions of current generations benefited the future. The “ideal society” was one “whose economy is in a steady state of growth (possibly zero) and which is at the same time just.”²⁹ The point of the savings principle was to secure growth until that society was reached, and to maintain affluence once it had been. Practically speaking, what this meant was that when a just society established its social minimum, the savings principle would be factored into the calculation. What counted as an acceptable social minimum in the present would be in part determined by how much the present generation needed to save for the future.³⁰

These ideas were modeled in the original position, where the just savings principle would be chosen as the principle that regulated relations across time. Yet this was not straightforward. The parties in the original position were meant to represent people from all parts of society. Would they include people from one generation or from every generation—from all “stages” of social development or from one? Rawls argued that incorporating parties from all generations did not work. To think of the original position as including all actual or possible persons would, he wrote, “stretch fantasy too far.”³¹ Instead, he introduced the “present time of entry” interpretation.³² The parties were contemporaries, but the veil of ignorance blinded them to which particular generation they collectively belonged. They shared a fixed temporal location in the present from which they chose the principles to govern the future. This introduced a problem. Why should the parties care about the future? If they were biased toward their own interests in the present, why should they save?

Rawls provided two lines of argument. First, he deprived the parties behind the veil of ignorance of knowledge of which generation they belonged to, so that they would not select principles that allowed any generation to deprive its successors. The second argument raised problems of moral psychology about the relative strengths of altruism, sympathy, and self-interest among the parties, whom Rawls described as “rational and mutually disinterested.” That meant they were impartial. Something more was required to make posterity matter. Rawls’s solution was to stipulate a “motivational assumption” to remedy present bias. The contracting parties were “regarded as representing family lines with ties of sentiment between successive generations.” They saved, that is, because they cared about their children (and their children’s children).³³ It was this additional stipulation that gave the future value. In correspondence with the economist Robert Solow, Rawls explained it as “given by the balance between what a typical son feels it reasonable to ask of his father and what this son is prepared to do for his sons. This balance varies as these compromised attitudes adjust to different levels of economic advance on the way to the conditions necessary for a just and well-ordered society.” This account was not entirely governed by the principles. Only one aspect of maximin remained: “The representative sons and fathers are thought of as belonging to the least advantaged group in each generation . . . what the least fortunate would be ready to save for their descendants is what settles the rate of capital accumulation.”³⁴ The just savings principle and its motivational stipulation was how Rawls got around the limitations of contract theory when facing the future.

These arguments were also in part Rawls’s response to a preoccupation of neoclassical economists. In the 1950s and 1960s, Solow, Edmund Phelps, and others proposed models of economic growth to explore the fundamentals of capital accumulation and consumption. These models, which theorized the relationship between rates of savings, interest, and growth—and tried to set balanced rates of consumption with savings and investments—had various implications for accommodating the future in calculations about welfare and the allocation of resources. This included the question of how future generations could be incorporated within economic decisions and what the role of governments might be in protecting them.³⁵

Rawls followed these arguments closely. His understanding of time and the future reflected those of the growth theorists, who traced their ideas to Frank Ramsey’s “A Mathematical Theory of Savings” (1928). Ramsey had formalized the terms of debate about the optimal allocation of resources across time by providing a solution to the problem of whether a nation should consume or save its income (if its goal was to maximize welfare over an infinite time horizon).³⁶ In 1961, Phelps put forward an influential model of growth that provided an alternative. He described a path of growth toward a “steady state” of high and sustainable consumption, which would be reached by following a “golden rule of accumulation.” This was the savings rate that allowed per capita consumption to be at its maximum possible constant value, as would the Solow growth model.³⁷ In subsequent years, the viability of the golden rule preoccupied economists. Ramsey’s placing of future generations on an equal footing with the present (by advocating a zero rate of pure time preference) was challenged. So was A. C. Pigou, who had placed high value on the distant future and saw the task of government as counteracting individual short-termism and acting as a “trustee for unborn generations.”³⁸ His theory was dismissed as “undemocratic” and “authoritarian.”³⁹ These older theories were said to require too much of present generations, demanding excessive savings and sacrifices for the future.

By the 1960s, a range of economists—Paul Samuelson, Amartya Sen, William Baumol, Stephen Marglin, and Gordon Tullock—were arguing over how the social discount rate, which gave a present value to future goods, could be adjusted to make savings efforts fair across generations by counteracting overly high savings rates that gave the future excessive weight. In the aftermath of Kenneth Arrow’s argument that democratic aggregation of preferences was impossible, some were skeptical about extending pricing tools from individuals to collectives: “the calculus of collective savings vs. consumption decisions,” Marglin argued, “was fundamentally different from the private calculus.”⁴⁰ Joan Robinson thought discounting the future could not solve the problems of present-future trade-offs in government.⁴¹ Others disagreed over whether government intervention was required to counteract individual time preferences, or whether such intervention posed a risk to democracy.⁴² But soon, few objected to thinking about the future in terms of the social rate of discount. Individual short-termism was assumed to apply at the level of society. While an earlier generation of economists had debated the psychology and morality of savings and investment, these debates gave way to the standard picture of economic behavior contained in the assumption of positive time preference. A certain theoretical structure was also assumed: the discount rate determined the rate of savings and ensured that the welfare of future generations had less weight than the present.

It was to these ideas that Rawls looked when he developed his just savings principle and when he described his own just society as aiming at a “steady state.”⁴³ Rawls wanted to make institutions last. He believed that endless growth was unnecessary to do so. But he also thought it was vital to set a savings rate to achieve a degree of intergenerational equity. Modernization arguments that might justify extreme inequality for the sake of future generations—either vast accumulations of wealth on the part of the rich or extreme hardship for the poor—were not permissible. Rawls, however, unlike economists, set his savings rate by an additional appeal to justice rather than utility. Only in non-ideal circumstances would discount rates be used. Justice constrained saving: each generation should save only as much as was necessary for justice to be secured.⁴⁴ In this respect, while the savings principle was not itself a principle of justice, it was still embedded within his broader approach. Yet Rawls did not want to give too much to the future. Just as he constrained the application of the difference principle in the justification for civil disobedience, or beyond national borders, now he insisted it did not apply across time. The demanding savings and redistribution that would entail was not required.⁴⁵

This ambivalence—the willingness to look to the future but circumscribe its present value—was reflected in Rawls’s justification for these ideas. The lines he drew between the parties in the original position and real individuals were here at their most blurred. It was not obvious, Rawls implied, that people alive today owed anything as a matter of justice to strangers in the future. Nor was it realistic to ask partial people, with limited time horizons, to save for posterity in general—only for their children, as “fathers . . . care for their sons.”⁴⁶ This assumption of individual short-termism entered the original position, in this gendered and patriarchal form, alongside the assumption of mutual self-interest. But Rawls also wanted to expand the psychological and moral horizons of the parties. The motivational stipulation entered as a way of coping with present bias, making the parties want to save for the descendants they cared about—those two or three generations along. Ties of sentiment were the motivational glue between overlapping generations, and ties of sentiment could stretch only so far.⁴⁷ It was up to just institutions to reach the parts of the future that sentiment could not.

Rawls’s account of the future reached an accommodation with growth theory by providing it with a set of moral constraints. He accepted its economic temporality of linear, infinite time horizons, but he also sought to view society from the “perspective of eternity.”⁴⁸ He thought morality was time-neutral, but he objected to discounting the well-being of future generations on time preference alone. On the one hand, the future was not less important simply by virtue of being further away. On the other, drastic redistributive action in its name could neither be easily justified nor accommodated within the frame of the two principles. This did not mean that concern for the future was not important. It meant that Rawls assumed things were getting better. Growth would continue. With certain reforms, justice could be achieved.

These assumptions that underpinned A Theory of Justice were made possible by the two decades of exceptional, unprecedented economic growth that characterized the postwar years.⁴⁹ But at the time Rawls’s book was published and read, this liberal optimism about the direction of the American economy and the capacities of government had been challenged by social unrest and economic downturn and would continue to falter with the stagflation that followed the end of the Bretton Woods settlement.⁵⁰ To some of his readers, especially economists like Solow and Arrow, Rawls’s demanding maximin principle, rather than his just savings principle, offered the basis for a more robust theory of intergenerational equity.⁵¹ For those concerned, however, with the current political predicament—the controversies over stalling growth, fiscal overreach, resource battles, and the energy crisis—the savings principle offered little by way of solution. The same was true for those concerned not with growth but with its limits. What struck philosophers was that Rawls seemed to have little to say about a problem that the humanitarian crises of the early 1970s made a key public concern: population.

The popular panic about overpopulation initiated by The Population Bomb came at the end of a decades-long period of political campaigning for global population control.⁵² In its wake, moral and political philosophers explored various ways of grappling with the population question. Many began with utilitarianism rather than Rawls’s theory.

As a technocratic theory of government, utilitarianism was historically associated with colonial policies of population control and eugenics, which had progressive as well as conservative iterations and were popular among British and American nineteenth- and twentieth-century liberals (a fact increasingly invoked by the late twentieth-century libertarian right to discredit government welfare programs).⁵³ In utilitarian moral and economic theory, trade-offs about the size and welfare of population were often analyzed in prosaic terms. Henry Sidgwick had distinguished two forms of utilitarianism: the “average” view, in which the community that had the highest average happiness per person was best; and the “total view,” where the best community was the one with the greatest total amount of happiness.⁵⁴ The average view advocated a population increase if the person born would have more happiness than the average person. On the total view, the larger the population, the higher the total amount of happiness. Population increases were thus advocated regardless of the happiness of each individual. To twentieth-century social liberals, accustomed to viewing the control of “quality” of life as part of politics, the total view was often rejected—not because population control was bad in itself, but because it encouraged the birth of people whose lives were not “worth living.”⁵⁵

When Rawls had turned to these problems in 1952, he wrote that the problems of “optimum population size” and “birth control” raised moral questions it was “repugnant to discuss.” Rawls was then still sympathetic to utilitarianism, but he had already made clear his aversion to any utilitarian suggestion that population expansion was a route to increasing welfare. There were circumstances where population control would be necessary—where it should be exercised by “social institutions in some orderly way, or else it will be exercised by war, famine, disease, and worse”—but population size was ideally left up to individual liberty.⁵⁶ In A Theory of Justice, Rawls was largely silent on population control, stating briefly only that a “reasonable genetic policy” might be important to a just state.⁵⁷ Privately, he wrote that he had “considerable unease in applying the conception of justice to the problem of population size.”⁵⁸ The control of life was not for Rawls the domain of politics.⁵⁹

Yet as overpopulation became a talking point, some suggested that utilitarianism could be made to deliver a justification for population control and rescued from its association with the “repugnant” total view. Just at the moment that Rawls mounted his attack on utilitarianism, others rallied to its defense. The new welfare economics had recently revived these arguments by placing the question of optimum population size within debates about growth and savings rates.⁶⁰ This brought to economic thought a streak of Malthusianism, which had been central in the nineteenth and early twentieth centuries but was pushed aside by growth theory’s confidence about technological capacities and demographic “transition.”⁶¹ Now this revived neo-Malthusianism sparked debates about how the future could be accommodated in a utilitarian calculus.

If all possible people in the future were included in calculations about welfare and utilitarianism was taken as temporally neutral, then large sacrifices would be demanded of the present for the sake of those future people. If only those alive today were included in the calculus, utilitarian calculations would be biased toward the present. Should utilitarianism be temporally neutral and include people across time—those yet unborn—in the calculus? Or should it include only those alive in the present? Did the same concerns also apply to Rawls’s own calculations? In 1972, the young Cambridge welfare economist Partha Dasgupta wrote to Rawls that he had gone wrong when he supposed that the calculus that compares “sums of utilities over various alternative social states” could not factor in the “unborn state”—the “‘state’ of not being born”—as one possible state to choose from. Once the unborn were factored in, everything would change. It was possible, Dasgupta insisted, for there to be levels of consumption below which welfare is negative. If that were the case, when those were summed, an increase in population size would not be advocated.⁶² The idea that the total view of utilitarianism always tended to population increases was incorrect.

These problems of population and the future also raised questions about the nature of morality. In 1967, the then utilitarian philosopher Jan Narveson asked what procreation duties fit with the utilitarian principle. Narveson delineated a conception of morality as concerned with relations between currently existing persons. Morality was “person-regarding”—it took as the only “ground of duty . . . the effects of our action on other people.” “Whenever one has a duty, it must be possible to say on whose account the duty arises—i.e. whose happiness is in question. . . . If we cannot envisage effects on certain people which would ensue from our acts, then we have no moral material to work on and we can do as we like.”⁶³ An act is bad only if it is bad for someone.

What did this mean for whether new persons should be brought into the world? If a person had not yet been born, they did not exist. They were thus not “subject to a moral relation,” since “morality has to do with how we treat whatever people there are.”⁶⁴ Utilitarians were only concerned with “increases and decreases with the general happiness,” conceived as the happiness of people; actions with no effect on the general happiness were “morally indifferent.” Whether to bring children into the world was usually a matter of moral indifference: it did not make sense to say that a child was “happier” as a result of being born. There was no comparison to be made, since the child’s happiness had not been “increased” by being born.⁶⁵ People in the present were what mattered: Narveson used this bounded nature of morality to argue that the extinction of the human race would not be a moral problem, even if it might well be a shame. If all morality was to be “person-regarding,” adding people to the population was morally neutral. “We are in favor of making people happy,” he wrote, “but neutral about making happy people.”⁶⁶

Yet Narveson, worried about overpopulation, added another argument. No moral considerations would arise until a child is born. But once born, there was a duty to reduce the child’s suffering. There was thus an asymmetry in the duties of prospective parents: while there was no duty to have a child, there were duties not to bring suffering people into the world. Like Singer, Narveson proposed a negative utilitarianism: its ultimate aim was not the production of happiness, but the avoidance of inflicting misery. To reduce misery where it exists, where we can predict that a child would be miserable, we have a duty not to have it. Moreover, when “indirect effects” were considered (that is, more than simply the happiness of the child), this argument for a duty not to have an unhappy child was strengthened. We have no right, Narveson thought, to produce a child who would burden the public, and so the public have the right to prohibit having miserable children who would burden the state.⁶⁷

With Narveson’s essay, population ethics was born. It took a particular form. Instead of exploring the controversial question of population control within an institutional framework, philosophers moved population out of the political realm and made it a problem for ethical theory. The moral problem of population was here recalibrated as a problem with the temporal orientation of morality and whether it was possible to have “obligations to non-existent persons.”⁶⁸ How could the future be made to count? There were two main responses. The first decoupled morality from persons. Some responded by arguing that utilitarian obligations were not owed to persons at all, but were obligations to bring about states of affairs, to produce goods, and to prevent evils: we have a moral interest in future happiness, not future persons.⁶⁹ This argument required that more people be added to improve welfare, so others amended it by swapping utilitarianism for general duties of benevolence aimed beyond persons, to form the basis of an ecological ethic. This would generate responsibilities concerning ecology, even if these were not conceived as responsibilities to future persons.⁷⁰

The second response was to retain the tie between morality and persons, but avoid the presentist consequences of only counting the living. Rawls had done this with his motivational stipulation that persons care for two or three generations into the future, as fathers care for their sons. Others, like Daniel Callahan, the director of the Hastings Center, a new applied ethics research institute, proposed extending the kinds of persons who counted to those who could be “implicitly contract[ed] for,” thus tying moral concern to foresight, limited to immediate posterity—the next hundred years or so.⁷¹ Extending moral concern to the future also posed difficulties for rights theorists, since many thought that only existing persons could be said to have rights. Rights needed a referent, a bearer. Some assigned rights to the not yet born by suggesting that future persons would have rights once they existed—they “will claim” rights in the future—so we should discharge our obligations to them as parents do for children.⁷² Joel Feinberg thought ascribing rights to unborn generations was possible because they had interests: “Interests can exert a claim upon us even before their possessors actually come into being, just the reverse of the situation respecting dead men where interests are respected even after their possessors have ceased to be.”⁷³ This did not mean that particular future persons had the right to be born, but that future generations, once in existence, would have interests that those alive today ought to protect—on the assumption that they would in fact get born. Similarly, it made sense to speak of the rights of unborn generations against us, given that we had duties to conserve our environmental inheritance for them (and where there were duties, there were correlative rights). Population control, moreover, might be sensibly reframed not as an issue of control but of rights.⁷⁴

These ideas had wide applications in ethics, particularly in medical ethics and in debates about the rights of unborn persons or those deemed without full capacity for moral personhood. They were used to consider euthanasia, “brain death,” abortion, and genetic engineering.⁷⁵ The search for general principles to cover multiple cases now extended to these debates about personhood and was accelerated by political developments. In the buildup to and aftermath of Roe v. Wade (1973), philosophers debated whether fetuses counted as persons, and whether potential persons had a right to life. In the Philosophy and Public Affairs abortion reader, they extended the use of thought experiments and intuition pumps from the ethics of killing to the ethics of abortion. The most famous defense of abortion was given in Judith Jarvis Thomson’s violinist example (which, with foresight, did not rely on the arguments from personhood that subsequently underpinned attacks on abortion).⁷⁶ Others foregrounded problems of personhood, the question of whether abortion rights denied the “potentiality principle,” and debated whether potential personhood entailed a right to life.⁷⁷

The abortion debates in turn had implications for population control: if potential persons had no right to life, not only was abortion permissible but population expansion could be halted.⁷⁸ In this connection between abortion and population control, liberal philosophers tracked the focus of the abortion rights movement. At the time of Roe, this was constituted in part by the women’s movement and privacy rights advocates, but also by the movement for population control that claimed to aim at the “reduction of suffering” at a global level.⁷⁹ Yet the connection between reproductive rights and population control was already disavowed by black and Native American women campaigning against coercive sterilization in the United States.⁸⁰ It would later be rejected as black and anticolonial feminists drew attention to the sterilization of women of color in the global North and, after the mass forced sterilizations of the Indian “Emergency” of 1975–1977, in the South.⁸¹ But in philosophy, the debate over abortion overall remained less concerned with political and economic problems of coercion and choice in access to medical care, and more closely tied to problems in the ethics of personhood, population growth, and future persons. The rise of applied ethics continued.

What made a future person whose existence we could predict different from one in the remote future whose future existence was uncertain? If potential persons did not have rights, what were the grounds of our obligations to future generations? In the mid-1970s, philosophers debated the implications of these questions for the reception of A Theory of Justice. Could future persons be incorporated into the original position?⁸²

Richard Hare thought that Rawls’s “present time of entry” requirement, which gave moral weight to existing persons but did not “shroud the question of existence,” showed that Rawls had “nothing to say” about population, abortion, and future and potential persons.⁸³ Others worried that making potential or future persons count led back to the total utilitarian view: if existence were shrouded, Rawls’s parties might choose to procreate on an enormous scale in order to raise levels of welfare.⁸⁴ If those who did not get born did not count, Barry argued, early extinction might be likely. As with an average utilitarian view, an ideal contract of actual human beings would recommend a “short time-span for the human race, as those who are alive splurge all the earth’s resources with an attitude of ‘après nous le déluge.’” By contrast, a timeless total utilitarianism that “enfranchises potential people” was biased toward actualizing potential people but not toward “spreading them over a long time-span.” It would not matter when welfare was at its maximum, so long as it was reached at some point. Extinction would be possible in that case too. Alternatively, if potential people included in a contract chose a principle other than utility, they might well recommend not bringing the human race into existence. If the difference principle were applied across all possible people, there would, in the course of human existence, be at least some people whose quality of life was such that they would prefer not to have been born; in this case, parties in the original position faced with maximizing the advantage of these least well off possible people might well choose not to bring anyone into the world at all.⁸⁵ To Barry, there seemed to be few good solutions.

Rawls himself sidestepped these concerns. In correspondence about population with Dasgupta, he insisted that the parties did not have to consider “the utility level of the unborn state, since this alternative is not open to them.” His stipulation that the parties include persons from two or three successive generations was enough “to bind the whole sequence together.”⁸⁶ But Rawls was also wary of these discussions for deeper reasons. In his 1974 presidential address to the American Philosophical Association, he went further, arguing that political philosophy in general could ignore “metaphysical” questions of existence and personhood.⁸⁷

Not all agreed. One philosopher who disagreed would become particularly influential, and his critique of Rawls would cut to the core of liberal egalitarianism. “The more I think about population policy,” the young Oxford philosopher Derek Parfit had written to Rawls in 1971, “the more puzzling I find the subject.”⁸⁸ That year, Parfit gave a seminar at Oxford on population ethics whose participants included Narveson and Singer. He developed a variety of arguments that were later circulated in articles, an unpublished manuscript on overpopulation, and, eventually, Reasons and Persons (1984).⁸⁹ That book had four parts. It explored rationality, time, personal identity, and problems of existence and future generations, as well as the “self-defeating” character of existing moral theories. “Philosophers,” Parfit wrote, breaking with his Oxford predecessors in the ordinary language tradition, “should not only interpret our beliefs; when they are false, they should change them.”⁹⁰

Prompted in part by the debates about population and personhood, Parfit used thought experiments to develop discrete, individually named arguments about the self, time, and the future. He suggested that accepted assumptions often rested on philosophical confusions, while certain philosophical problems were intractable. The first idea Parfit set out to change was the view put forward by Bernard Williams, among others, that personal identity was determinate, or tied to physical identity.⁹¹ This view held that having the same functioning brain was enough to say that a person was the same person. Parfit argued instead that the continued existence of a person involved no more than relations between mental states at different times. People were not continuous selves, but aggregates of psychological experience. This had significant implications for how to think about the future. Most people care about the future because they think it is their future. For Parfit this was a mistake: our later selves are more like separate people than like us. What made it rational for me to care in a special way about my future fate was not that the person in the future will be me, but that they will be psychologically related to me.⁹² On this deflationary view, personal identity was not what mattered.

Another of Parfit’s arguments, the “Repugnant Conclusion,” built more explicitly on the utilitarian population debates. It reinterpreted the idea that total utilitarianism justified adding additional people (as many as would have lives worth living) to a population as a route to increasing welfare—and that this was the case even if their lives might be miserable, and even if it led to overpopulation.⁹³ But of all his arguments about the future, the most immediately influential was his “non-identity problem.” This was the paradox created by the fact that our decisions today affect what individual people will exist tomorrow; different courses of action bring different people into existence. When we talk about whether future people will be better or worse off as a result of our choices, actions, and policies, we cannot therefore expect that the same people will exist to be affected by one or another of our choices. Parfit distinguished between future people (who will exist whichever way we act) and possible people (whose existence depends on our actions). Asking whether “our decision not to have children” could harm these possible people’s interests, he answered no. We cannot harm those whom we do not conceive. When we act in a certain way in the present, different particular people will be born. Given this, if what Parfit described as Narveson’s “person-affecting” view was taken seriously, no one in the future would be worse off because of our actions in the present. The happiness of people who would have been born if we had acted in a certain way cannot be compared to people who were not born because we acted in a different way. Did this mean that there were no obligations to the future, because there were no particular persons to whom we had obligations?⁹⁴

Parfit wanted to avoid this conclusion. Some acts that brought people into existence were wrong even though they did not make things worse for, or were not bad for, the person they caused to exist (or for any other existing or future person). In place of the person-affecting view, Parfit presented an impartial one. If morality did not always affect a particular person, then it was not morally significant that different future people were affected by our actions. Depleting resources could still be morally objectionable. We just had to get rid of the idea that the only way it could be was by affecting someone in particular.⁹⁵

These ideas formed the basis for subsequent debates about environmental ethics and the future. If no one in particular could be said to be worse off because we squandered resources, how, then, should we explain why it mattered morally whether or not resources were depleted?⁹⁶ Numerous journals and volumes, entitled Ethics and Population and Obligations to Future Generations, now dedicated essays to Parfit’s ideas about identity.⁹⁷ The implications of the non-identity problem divided moral and political philosophers. Some resisted its force, arguing that who the members of future generations turn out to be should not matter to the ethical assessment of our acts that affect them. Others suggested that the consequences of the non-identity problem were impossible to avoid: the question of how choices in the present affect the composition of future generations will delineate what choices about the future are permissible.⁹⁸

After Parfit’s interventions, population ethics exploded as a distinctive field of “moral mathematics.”⁹⁹ But population also steered moral philosophy back to foundational questions—in the opposite direction from Rawls’s attempt to hive off the political from the meta-ethical and metaphysical. The ethics of population, Narveson observed, required philosophers to return to problems of identity, of “logic, semantics and metaphysics.”¹⁰⁰ Parfit challenged Rawls in other ways too. For instance, Rawls had argued that utilitarianism did not take seriously the separateness of persons and, through the impartial spectator device, extended the principles of individual choice to social decision-making, thus conflating different persons into one. On Parfit’s view of identity, the idea that there was a metaphysical distinction between persons was mistaken. Utilitarians could be justified in ignoring the distinction between persons, for the distinction was not what it seemed.¹⁰¹ This cut against liberal egalitarianism’s focus on individual moral persons as the only true subjects of morality. “Persons,” Parfit wrote elsewhere, “are like nations, clubs or political parties.”¹⁰² Here he implied an ontology that might have supported the young Rawls’s pluralism, yet it was one that Rawls would have shied away from. Parfit himself did not refocus philosophical debate on collectivities above the individual, but on points of existence below it. His “dismantling of identity” provided a “utilitarian analogue” to poststructuralism, Perry Anderson observed—one grounded, ironically, in a “materialist response to the arrival of medical transplants and genetic engineering” (a list to which Anderson might have added population control).¹⁰³

Parfit’s critique of self-interest theories was also part of a broader effort among moral and political philosophers to resist the overreach of neoclassical economic ideas and assumptions about the rationality of individual motivation. In the late 1970s, a number of prominent economic thinkers were challenging neoclassical orthodoxies of economic rationality. Robert Heilbroner, for instance, argued that such views of rationality had diminished society’s sense of ethical responsibility for the future. Economic rationality gave no convincing answer to why we should care about the future and instead framed the question as “what has posterity ever done for me?” What was needed was a “survivalist ethic” to commit us to “life’s continuance,” to defy the “homicidal promptings of reasonable calculation,” and to discover the “transcendent importance of posterity.”¹⁰⁴ Amartya Sen, Martin Hollis, and others joined the new behavioral economists to critique “rational economic man” and the “rational fool” of homo economicus, characterized by the view of “abstract individuals” choosing between “abstractly defined alternatives.”¹⁰⁵

The ideas about personal identity that Parfit proposed similarly undermined received notions of self-interest, “laissez-faire,” and economic rationality and dissolved certain philosophical puzzles altogether—such as the rationality of individuals sacrificing something now for the future, and the choice between action now and action later.¹⁰⁶ Parfit implicitly challenged Rawls’s adaptation of economic ideas. He rejected the use of social discounting techniques for weighing future risks.¹⁰⁷ Discounting entailed treating matters of morality as if they were questions of monetary value and was a clumsy way of accommodating temporal problems. Its absurdity was obvious, Parfit suggested, if time was compared with space: “No one thinks that we would be morally justified if we cared less about the long-range effects of our acts at some rate of n per cent per yard.” Time should be the same.¹⁰⁸ His broader theory reinforced this. Not only must we be careful about imposing future consequences of our own actions onto other people. Since our future selves are not simply extensions of our present selves, but in important respects separate persons, we should be equally careful of imposing those consequences on our future selves. The question of when became irrelevant.¹⁰⁹

Taken together, Parfit provided a set of arguments that were independent of the Rawlsian apparatus, and that pushed philosophers toward an ethical impartiality in which the value of states of affairs was independent of their impact on particular people.¹¹⁰ Both person-affecting views and total utilitarianism were replaced by a theory that evaluated acts rather than agents, and that could account for something being wrong without it having to be wrong for a particular person. In Parfit’s wake, the search for an impartial ethic proliferated. Yet among the philosophers of public affairs, there began to be disagreement about the political uses of such an ethic. Parfit created more puzzles than he solved, but his philosophical talent became the stuff of legend. For some quarters of moral and political philosophy, it was conceptual coherence and sophistication like his that mattered above all. Others suggested that the value of moral theory—though often a response to public affairs—could not be judged by its “practical effects.” If our beliefs were in error, then we should change them, but we need not believe that philosophy could change much else. For some this was cause for political pessimism: “Moral judgment and moral theory certainly apply to public questions, but they are notably ineffective,” Nagel wrote, conceding normative theory’s limits: “When powerful interests are involved it is very difficult to change anything by arguments, however cogent, with appeal to decency, humanity, compassion or fairness.”¹¹¹

The relationship of the philosophers of public affairs to politics during the Vietnam era had been strikingly synchronous. That began to change as many philosophers shied away from political controversy. Some now sought in abstraction not the solutions to contemporary political life, but a kind of refuge from it. This refuge view of philosophy allowed for the persistence of the discourse of overpopulation in ethics long after it became politically toxic. In part, this persistence was due to Parfit’s influence, but it was also because of the extent to which population ethics abstracted from concrete political problems. At the moment that population control and the regulation of reproduction became politically fraught, with the New Right’s backlash against reproductive rights and the embrace of feminist and antiracist critiques of eugenics, philosophers looked to these complex problems of “moral mathematics” at a “higher order of abstraction.”¹¹²

For some of Rawls’s followers who were engaged with international and humanitarian ethics, this was an inadequate response. They opted for a different route, trying instead to bring the life-and-death ethics of population into the framework of justice, obligation, and ideal visions of society. For Rawls’s student, the Kantian moral philosopher Onora O’Neill, the utilitarian debates about population had not taken seriously the “imminence” of the situation brought about by overpopulation, famine, and the world food crisis, and they ignored its “implications for today.” They had been concerned with the question “how many people should we add?” when what mattered was “how few people could we lose?”¹¹³

In “Lifeboat Earth” (1976), O’Neill sought to develop an ethics appropriate for a society that was not much like a game or cooperative practice. The metaphor of the lifeboat was the most fatalistic of recent efforts to theorize the “whole earth.”¹¹⁴ It was a response to another, which had come to prominence when Adlai Stevenson, in his last speech as American ambassador to the United Nations in 1965, described the earth as a spaceship.¹¹⁵ On spaceship earth, resources were limited, life was fragile, and the time to save it was running out. As passengers on a spaceship with finite resources and no exit, we—the inhabitants of the earth—had to cooperate and steer it in the right direction. We were all in it together. The image of spaceship earth became central to a strain of antigrowth ecological economics associated with Kenneth Boulding and Herman Daly.¹¹⁶ For the neo-Malthusian biologist Garrett Hardin, however, earth was not a spaceship, but a lifeboat. The world’s peoples were not one harmonious crew, working together with a captain steering the ship to safety. Instead, the passengers were disorganized, their fates intimately connected as they battled for space on a tiny boat, with too many on board and not enough food or fuel to last. With the threat not uncertain but imminent, some would have to get off—if not of their own accord, they would have to be pushed. Their aim was not peace and stability, but survival.¹¹⁷

Hardin had come to notoriety with his “The Tragedy of the Commons” (1968), which argued that individuals acting in their own self-interest were destined to deplete the world’s common resources. By the time he published Explaining a New Ethic for Survival (1972), that earlier essay had been reprinted more than two dozen times, and the ongoing food and agricultural crisis seemed to confirm fears that population growth would outstrip food provisions. For ecological economists like Boulding, who appealed instead to a cosmopolitan ethic in the name of the earth, these problems were caused by the fixation on growth under capitalism.¹¹⁸ For Hardin, the population “explosion” required existential, coercive intervention to make the future safe for capitalist civilization to survive for the few. The stakes were civilizational, and the solutions were national: “If we renounce conquest and overbreeding our survival in a competitive world depends on what kind of world it is: One World, or a world of national territories,” he wrote. “It is unlikely that civilization and dignity can survive everywhere; but better in a few places than in none.” In Hardin’s racist vision, population control in poorer nations was necessary for capitalist growth to survive. “Fortunate minorities,” he continued, “must act as the trustees of a civilization that is threatened by uninformed good intentions.”¹¹⁹

In the panicked atmosphere of the 1970s, as philosophers began to explore the possibilities for ethics in the context of famines, population scares, and the “limits to growth” thesis, Hardin’s lifeboat vision was taken up by liberal philosophers—even though it required drastic coercion and implied a view of society incompatible with a Rawlsian cooperative scheme.¹²⁰ O’Neill thought the metaphor of spaceship earth suggested too much “drama” and too little “danger.”¹²¹ A more likely future was the lifeboat situation of emergency and radical scarcity. “Even the more optimistic prophets place it no more than decades away.”¹²² For O’Neill, lifeboat earth was a thought experiment as well as a possible future—one of philosophy’s now typical “lurid situations.” She used it to explore the rights and obligations of those alive in the present to prevent future deaths, from famine and starvation: the ethics of life and death in the “present situation of global sufficiency of the means of survival and the expected future situation of global insufficiency.”¹²³ As population control became a fixture of debates about humanitarianism and US foreign assistance policy, O’Neill brought population into the new international ethics of human rights, justice, and international obligation, combining these ideas with the wartime approach to the ethics of killing.¹²⁴

O’Neill argued that emergency famine situations required both drastic global famine policies (maximizing the means of subsistence) and population policies (minimizing the number of people) in order to prevent future disasters and long-run scarcity situations. Famines were inevitable unless fertility was curbed, pollution reduced, and consumption patterns altered.¹²⁵ O’Neill grounded these policies in what she called our “right not to be killed.” Against the use of double effect and the distinction between killing and letting die to limit moral responsibility, O’Neill showed that once the causal chains between famine deaths in poor countries and the actions of individuals, governments, and corporations in rich ones were properly understood, those actions could be properly described as forms of killing.¹²⁶ In normal, nonscarcity situations on a “sufficiently equipped earth,” “some persons are killed by others’ distribution decisions.” We can all be threats to the lives of others: even when we are what Nozick called “innocent threats,” our distribution decisions can nonetheless kill.¹²⁷

O’Neill pointed to a causal connection between famine deaths and a variety of actions, including wage-setting and commodity pricing decisions, which violated individuals’ rights not to be killed. In the coming lifeboat situation, the effects of all this would be more severe. Some killing would likely be unavoidable. But taking the right not to be killed seriously and acting on our distinctive duties “to prevent and postpone famine deaths” required that we enact policies that would prevent complicity in future deaths.¹²⁸ Such policies were crucial to avoiding killing in the present, as well as a future situation of global scarcity in which we might have to choose who to kill and who to save. If we did not act now, we might get to a point where “further grounds” would be sought to “justify overriding a person’s right not to be killed,” and where that right might justifiably be violated. To prevent such scenarios, it was necessary to support charities like Zero Population Growth and policies that could range from the “mild to the draconian”—from contraception to sterilization to the “elimination of further births”—depending on the estimation of the threat.¹²⁹

Survivalism here met with a cosmopolitan humanitarianism and became not its opposite but its twin. Hardin’s survivalist ethics had threatened cosmopolitanism, but O’Neill brought them together in a politics of emergency that assumed crisis would become norm. On the one hand, this was a morally demanding account of individual moral responsibility, common to neo-Kantian Rawlsians.¹³⁰ On the other, she joined the international ethicists who prioritized a minimalist ethic of sufficiency that preceded the demand for justice, appealing to fundamental rights that were not relational but tied to bare life. Like Shue, O’Neill saw food as different from other problems of inequality: as a question of subsistence, beyond a normal framework of distributive justice.¹³¹ Global inequality was one cause of famine deaths. In her lifeboat situation, the control of the means of subsistence was unequally distributed: some passengers traveled first-class, others were stowaways with no property rights at all. Inequality created the situation in which the investment decisions of corporations or governments could cause famine deaths. But solving inequality was not part of her prescribed solution, and like Singer, she did not specify what institutions should discharge individual duties. An absence of property did not deliver a claim to redistribution. Property rights were not implicated in rights to subsistence, which existed separately from a given distribution and were not relevant in the face of life and death.¹³²

O’Neill’s ideas were part of the current within liberal philosophy that focused on emergency and subsistence rights separate from practices and systems of property. The apparatus of justice theory was not required. Moreover, in this context, justice theory had a grave limitation. Rawls’s “circumstances of justice”—those facts about the world that had to be in place before the principles could apply—included an assumption of moderate scarcity. The lifeboat, with its situation of severe scarcity, was a long way off from the circumstances of justice. Any survivalist theory that flowed from it, however cosmopolitan, required a different imaginary. O’Neill’s right not to be killed, Shue’s basic rights, and even Richard Falk’s right to a “liveable environment,” which he proposed following the environmental damage wrought by the Vietnam War as part of the legal category of “ecocide”—all these issued in obligations to aid or avoid harm, which existed outside the bounds of justice and egalitarianism.¹³³ Yet even where they assumed that population size should be controlled via policies of conditional aid, none agreed with Hardin that keeping the lifeboat afloat mattered more than relieving suffering, or that aid might contribute to sinking the lifeboat. The relief of suffering in the present was always a priority for liberal humanitarian philosophers and a constraint on survivalist policies, whether in solutions to address catastrophic prophecies of overpopulation or in plans for international redistribution like those contained in the Brandt Report, subtitled A Programme for Survival.¹³⁴

There were other philosophers, however, who rejected any future-focused plans for survival that required drastic action in the present, often on grounds of conceptual incoherence. John Passmore suggested that uncertainty about the future required that immediate posterity be given priority. Martin Golding, a fellow at the Hastings Institute, agreed that the future was too uncertain to justify action for its sake. We did not know what future generations would want or what ideals they would have. “Remote” generations were unlikely to be much like us, so we did not know “what to desire for them.” Uncertainty about the distant future meant that no shared moral community could be assumed. Rights and obligations were established by membership in a moral community and a shared conception of “the good life.” Future generations were owed things only insofar as they were members of “our” moral community.¹³⁵ Instead of succumbing to “ecological panic” and planning for “mere survival,” what mattered were obligations to “immediate posterity,” “not to plan for them”: we should only remove obstacles that stood in the way of future generations “realizing the social ideal.” To say more would be “gambling in futures.”¹³⁶

These kinds of arguments from uncertainty were increasingly common in the 1970s, particularly among neoliberal thinkers. They invoked uncertainty and information problems as part of their critiques of planned and measured economies that purportedly limited options in the future. In the context of the population debates, neo-Hayekian technological optimists like Herman Kahn and Julian Simon condemned catastrophism and sought to show that the “doomsayers” were wrong: given uncertainty, and assuming the advancement of technology and an unfettered market, the future could take care of itself.¹³⁷ Kahn and Simon condemned Ehrlich, Hardin, and population theorists and also any state or coercive action that planned for the future, including “redistribution” and “reducing inequality.” Arguments against population control were deployed against planning, the state, and investment for the future in general.¹³⁸ The young Keynes had been a Malthusian; now many anti-Malthusians were also anti-Keynesians.¹³⁹ Planning for the earth’s survival was a concern for advocates, not critics, of state action for welfarist ends.

But could that survivalism be part of an egalitarian theory? By the mid-1970s, some were trying to show how liberal paradigms, from discrimination law to Rawlsian justice, could accommodate ecological concerns.¹⁴⁰ Philosophers debated whether Rawls’s theory was adequate for the challenge.¹⁴¹ “He does not so much as mention the saving of natural resources,” objected Passmore. “How rare it is for moral philosophers to pay any attention to the world around them!”¹⁴² Rawls’s theory demanded too little for future generations. Though he ensured they were entitled to savings, the savings principle did not deliver the redistribution of the difference principle, nor the sacrifices of temporally neutral utilitarianism. Some also objected to the overextension of the distributive paradigm and to the casting of relationships with nature in distributive or economic terms. It was “strange,” Laslett wrote, to try to cover all intergenerational relationships with savings, since “an argument about social relationships in general which is based on ownership of material things is hardly likely to be reputable.” In any case, “the one thing any society at any time could be relied upon to do is save.” The problem was how to avoid wasting and consuming “important elements in the environments, in the way that the Ancients used up gold, or the Elizabethans the English forests.”¹⁴³

Brian Barry tried to fit together the concerns of equality and ecology. While he was experimenting with extending theories of justice internationally across the world, he was also looking to stretch moral principles into the future to accommodate problems like overpopulation and resource depletion. In 1973, he wrote that political theory had to come to terms with the “ecological” viewpoint.¹⁴⁴ This he associated with the anticonsumerist critique of growth and materialism by the British ecological movement, with its philosophy of “enoughness” exemplified in E. F. Schumacher’s Small Is Beautiful (1973).¹⁴⁵ In the light of “exponential growth” and the “interdependence” of nations, as well as that of living and nonliving things, its relevance was “irrefutable.” “The human race is on a crisis course,” Barry wrote, and “only a sharp reversal in many of our ingrained ways of thinking can avert a catastrophe at some point in the future.” Where Parfit thought ecological and population problems, like other collective action problems, required moral solutions, Barry thought ecological problems reaffirmed the importance of politics.¹⁴⁶ There would be no moment, as “Victorians of left and right” had hoped, when productive capacity reached a point where it could provide “sufficiency for all” and remove the conflict at the basis of politics. Ecological crisis made political problems “more intractable” by revealing existing inequalities and “widespread and acute” conflicts of interests.¹⁴⁷ Given this, the task was to find a way to accommodate obligations to future generations.

In 1977, nearly two decades after the resurgence of theories of obligation, Barry surveyed the philosophical scene. Theories that grounded obligation in mutual protection, self-interest, or community were all guilty of “disregarding the future,” especially the remote future after “our grandchildren” are dead.¹⁴⁸ The tradition that ran from Hobbes and Hume to Hart and saw morality as nothing more than “mutual self-defence” could not generate obligations to future generations, who had no “bargaining power” and could not reciprocate; it thus made sense to ignore their interests. Communitarian theories, like Michael Walzer’s, in which obligations depended on “actual rather than potential reciprocal relationships,” ruled out obligations to subsequent generations too. Worst were arguments like Golding’s for selective future obligations, which required membership in a moral community. This Barry found “more morally offensive than a blunt disregard of all future interests.” It was “a diachronic version of the common American view that famine need only be relieved in countries with the right attitude to capitalism.”¹⁴⁹

It was better to say that “our moral principles hold without temporal limit.”¹⁵⁰ In practice, “atemporal morality” had unacceptable consequences. Even a timeless utilitarianism could be turned into a theory that protected only immediate posterity, by adding concerns about uncertainty and ignorance.¹⁵¹ “In the context of universalistic utilitarianism the appeal to ignorance normally functions as a smoke-screen, to conceal the fact that we are simply not willing to act in the kind of saintly way that a serious application of the doctrine must entail.” Passmore had abused uncertainty in this way. Economists did no better: they were guilty of “drawing blank cheques on the future to cover our own deficiencies.” This “attitude of expecting something to turn up would be rightly considered imprudent in an individual,” Barry wrote. “I do not see how it is any less so when extended to our successors.” Libertarians similarly licensed caring little about the future. Nozick’s natural rights to property entailed a “right to dispose of our property as we wish,” and justified potentially unlimited consumption and resource destruction.¹⁵²

A “new ethic” would, at minimum, “include the notion that those alive at any time are custodians rather than owners of the planet, and ought to pass it on in at least no worse shape than they found it in.”¹⁵³ For Barry, Rawls’s focus on goods to be saved, rather than harms to be prevented, belied an economic temporality typical of growth theories that misunderstood the temporality of ecological concern and where and when its political difficulties and solutions lay. “Investment,” Barry argued, “has a characteristic that enables discussion of it to dodge the most awkward difficulties.” It relies on the actions of intervening generations to help remote generations. Though present generations might save with their remote successors in mind, there is nothing to guarantee that the next generation will too. Focusing on the just savings rate reduced intergenerational relations to the relations between a generation and its immediate successors, and to the behavior of those later successors, “whom we have no way of binding.”¹⁵⁴

The same was not true of avoiding harm. Conservation for remote successors might depend on the actions of immediate successors. But what of those “ecological sleeper-effect that we set off now with no ill effects for some hundreds of years and then catastrophic effects”? Sleepers—actions that have more significant effects in the long run than the short run, or those that are beneficial in the short run and harmful in the long run—had to be taken into account.¹⁵⁵ There was a major distinction between “investment, which has the property that our successors can choose whether to pass on the benefits we leave them, and ecological damage, which has its own adverse effects on remote future generations whether or not our successors add to it.” Rawls had collapsed two problems into one. “The really nasty problems,” Barry wrote, “involve obligations to remote descendants rather than immediate descendants and on these Rawls has nothing to say.”¹⁵⁶

Rawls had been more concerned with problems of stability than survival. Still, Barry believed that obligations to the future had to fit within the framework of justice. Duties of humanity and benevolence were insufficient. He tried to amend Rawls’s assumptions about growth and self-interest to make justice theory fit an ecological age. By turning to familial ties as a motivational assumption, Rawls had both inserted his own prejudices about the importance of the family and undone the technical beauty of his theory, blurring the lines between the parties in the original position and real-life persons. For Barry, giving preference to immediate successors placed unnecessary temporal limitations on the scope of justice and biased the theory to the status quo by making justice “parasitic” on the “sentiments people actually have.” Thus, the “limits of caring were the limits of justice.”¹⁵⁷ But the task for any moral theory of the future was, as one philosopher put it, to “break the bonds of self-concern.”¹⁵⁸ Theories that relied on present interests or sentiment tended to miss that because the interests of particular individuals in the present were “interdependent” with those in the future, the welfare of future generations had to be conceived of as a public good.¹⁵⁹ Moreover, interest theories were, the British political theorist John Gray wrote to Barry, “offensively anthropocentric.”¹⁶⁰

Barry was reluctant to give up on them. But though it gave him “great intellectual discomfort,” he saw doing so as the only way of generating an ethic appropriate to an ecological age. He came to believe that it was impossible to derive the value of human existence from an account of the interests of actual or future human beings. Nor could the aversion to the extinction of the human race be explained by the idea that extinction would injure the interests of those “who will not get born.” To explain that aversion conceptually, there was no choice but to disconnect ethical principles from interests. Only by appealing to something beyond human interests, to what he called a sense of “cosmic impertinence,” could Barry find grounds to oppose the extinction of the human race—a position that he saw as necessary for any ecological theory.¹⁶¹

This insight was tied to another critique of Rawls; taken together, these pushed Barry, like many of his contemporaries, to consolidate his emphasis on the hypothetical. He again attacked Rawls as the heir to the Humean tradition that relied on reciprocal institutional practices as the condition for a theory of justice and deemed the circumstances of justice—of “moderate scarcity, moderate selfishness and relative equality”—as necessary for its application.¹⁶² This requirement excluded from the scope of justice relationships in which the circumstances did not apply—with animals or between generations. By upholding the condition of moderate scarcity, Rawls ruled out the relevance of justice in scarcity situations, whether postwar Britain, where rationing was necessary, or any scenario of the future put forward by even optimistic ecologists.

For Barry, Rawls’s parochialism ran deep. Only an affluent postwar America supplied the background conditions of his just society. Accepting the “insidious” Humean circumstances as necessary for justice made the future far too bleak.¹⁶³ The moderate scarcity clause should be removed—not because the future was uncertain but because it made Rawls’s justice, like Hume’s, too fixated on property rules. If justice was simply the rules of property, then its requirements could be waived in situations of extreme scarcity. To concede that justice only applied in conditions of moderate scarcity would be to concede that the ethics of lifeboat earth amounted to no more than simply pushing overboard those who weigh us down. What was needed was a criterion for evaluating who should get what in conditions of scarcity. Barry discarded the Humean dimension of Rawls that provided a theory of agreement and an understanding of contractualism as “justice as rational co-operation,” for the Kantian theory of hypothetical choice, “justice as universal hypothetical assent.”¹⁶⁴

As with the debate over international justice, the intergenerational context revealed the divergence between these two dimensions of Rawls’s theory in the hands of his interpreters. At the turn of the 1980s, the move from the empirical to the hypothetical was made across both space and time. Strangers in the future, Gregory Kavka argued, had just as many needs as strangers in the present. The same hypothetical maneuver that had been performed to justify obligations internationally was now required to do so for the future.¹⁶⁵ David Richards saw the idea of a Kantian moral person as providing the grounds for considering relations between generations—as well as relations globally—as if they were reciprocal.¹⁶⁶ Barry focused on Rawls’s second argument in the original position to make the future matter. For the theory of mutual hypothetical assent to work for the future, the parties in the original position would have to be drawn from every generation, but would not know to which they belonged. For Barry this meant they would choose not a principle of just savings but a principle that took seriously the idea that later generations would regret not restricting “resource depletion and damage to the environment.” They would choose a principle of equality of opportunity, which would leave the future open. This was not tied to the circumstances of justice, but was concerned with the right to an equal control of resources in an initial position. Justice demanded not that present generations make the future better off, but that they not use up resources and narrow the overall range of opportunities the future would enjoy.¹⁶⁷ Where resources were unavoidably used up or opportunities closed down and future generations were denied choices, they should be compensated.¹⁶⁸

At the same time that liberal egalitarians removed historical questions about reparations and rectification from distributive justice, others incorporated compensation for the future. Compensating for depleting nonrenewable resources took the form of investments to preserve the range of opportunities for future generations—by giving them at least the amount they would have had if we had not acted in the way we did.¹⁶⁹ Barry did not argue that one day we might go beyond growth and reach a stationary state. This was the preoccupation of the “sentimental” Victorians he dismissed.¹⁷⁰ Instead, his account of obligations to the future focused on harm prevention. Yet though his concern with survival made him pessimistic, Barry arrived at a theory of openness: an open-ended account of present obligations to the future in which obligations were born not of humanity or rights to sufficiency but of justice and equality. An open future, he argued, was possible even in scarcity. Even as the catastrophist intuitions of political philosophers subsided, particularly about population growth, such aspirations to openness would characterize many subsequent theories of intergenerational justice. These often became tied to a vision of the abstract, remote future in which time was collapsed and flattened and tomorrow became morally the same as today.¹⁷¹ This was due in part to justice theory’s hypothetical justification. Once divorced from empirical considerations, theories of the future could fit a survivalist landscape as easily as one of moderate scarcity. After the late 1970s, more philosophers and economists took up the challenge of integrating scarcity concerns into egalitarianism—first, gradually, in the context of energy depletion and nuclear energy, and then in greater numbers once the threat of climate change made environmental concerns central.¹⁷² As others tried to accommodate obligations to future generations within justice theory, they upheld the abandonment of present bias and empirical circumstances that had characterized the interest theories Barry contested and the person-affecting theories Parfit rejected.

On the one hand, then, a hypothetical account of justice and an impartial view of morality won out. The framework of Rawls’s theory was stretched to accommodate even those survivalist ideas that threatened its fundamental assumptions. On the other hand, Rawls’s institutional emphasis was interrogated less. As morality stretched into the far future, theories that gave existing institutions, communities, or families a special role in generating reasons to care about the future were largely set aside. Philosophical treatments of the future became conceptually independent of either the circumstances of justice or other institutional contexts. Problems of political institutions, designed to deal with the fact that reality often fell short of morality, were replaced by those of identity or individual choice.¹⁷³ Rawls’s initial concern with savings and discount rates remained, but as moral and political philosophers borrowed increasingly from welfare economics, these technical questions were detached from Rawls’s ethical apparatus and from the worry about whether individual decisions could be scaled up to collective ones. The concern with discounting suggested that discharging obligations to the future could be analogized to individual preferences in a marketplace. By the 1980s, models of intertemporal choice, developed in collaboration with behavioral economists, featured centrally in debates about energy policy and became crucial to securing the new liberal environmental aim of “sustainability.”¹⁷⁴ These choices about the future were themselves deinstitutionalized: individual choices, not institutions, played a role in making the future present. Indeed, when behavioral economists later wielded substantial influence at the level of government, their policies about the future took the form of “nudging” individuals to make decisions about their own futures, not creating institutions to plan for the future conceived as a public good.¹⁷⁵

The temporality of Rawls’s theory, particularly its reliance on an optimistic vision of growth, persisted across liberal philosophy and underpinned this incrementalism. Even as he had tried to dispense with teleological assumptions and explicit philosophies of history, his vision was nonetheless premised on the assumption that long-term economic equalization would continue. Later, Rawls tried to correct for this limitation by stressing that justice as fairness was compatible with a society beyond exponential growth. He merged growth theory’s idea of the steady state with John Stuart Mill’s idea of the stationary state, which he had previously mentioned only in footnotes.¹⁷⁶ In a 1985 lecture on Mill, Rawls explored Mill’s stationary state as a version of a well-ordered society, one in which institutions were arranged “to preserve the natural world so that all the higher pleasures can be pursued by all citizens under conditions of equal justice.” The stationary state was a society where high productivity, low population growth, and a shorter working day—as well as the absence of an “idle class” of rentiers who did not work—allowed workers to lead a “decent life” and pursue the higher pleasures. Rawls was pessimistic about whether such a state could be realized. Mill, he wrote, had been “apolitical,” for he “underestimated the dynamism of capitalism” and “the depth of political conflict.” “He seems now at least,” Rawls wrote, “too optimistic.”¹⁷⁷

With age, Rawls thought the same about his younger self. In the decade after A Theory of Justice was published, philosophers had explored new visions of the future: of future persons and scarcity scenarios and theories of savings, openness, and intergenerational justice. Though born of crisis, few were dynamic. Rawls grew more anxious about the objection that his theory was a mere defense of capitalism. Yet he responded by looking not to forms of dynamism but of stasis. He wanted to show that his theory might accommodate a stationary state, even if he was more pessimistic than Mill about its realization. Disillusioned with the postwar concern with growth that had underwritten his theory, he became insistent that the ideology of the “capitalist business class,” of “economic growth, onwards and upwards, with no specific end in sight,” led to a “civil society awash in a meaningless consumerism . . . which we already have in the United States.”¹⁷⁸

This critique of endless growth signaled the deepening of Rawls’s anticonsumerism. It also reflected his growing worry about the persistence of greedy capitalists in his just society. This was a response to his critics who thought his theory permitted such capitalists, and part of Rawls’s broader concern that interpretations of his theory as institutionalist—as not concerned with moral psychology or agency—had entrenched the division between theories that gave altruistic or humanitarian defenses of the voluntary principle and egalitarian institutionalisms reluctant to judge individual behavior. This division would come under scrutiny in subsequent years. Yet these concerns did not reflect a major transformation of Rawls’s theory of the future itself. Rawls did not change the temporal underpinnings of his savings principle to address the limits to growth. That would have involved not just appending Mill’s stationary state to the list of societies his theory could accommodate, but also altering the orientation of the theory itself.¹⁷⁹

What liberal philosophers did not address was the crisis in the politics of growth that hit when the growth and productivity gains that had legitimated the postwar political settlement stalled. In that fiscal crisis, Marxists saw the state’s support of capitalist accumulation, obscured by social spending, now revealed.¹⁸⁰ Social conservatives thought the crisis was the result of unrealistic demands born of affluence, but they agreed that the state would continue to face difficulties unless citizens asked for less and adjusted their expectations.¹⁸¹ Neither diagnosis caught the attention of liberal philosophers. They continued to assume that the welfare state and social democracy would be fine. By and large, they passed up the opportunity to think about what justice might look like in circumstances where growth was not assured, or to consider how the egalitarian vision might be maintained in a different political and economic settlement. Only Barry tried to do so, by implicitly decoupling justice from growth.¹⁸² The legitimacy crisis passed philosophers by. Yet its ideological consequences would become impossible to ignore.