Philosophy for the Long Run: Introduction to the Symposium on Longtermism

Longtermism is the view that a, or the key moral priority of our time is to positively influence the long-term future – the next hundreds of thousands or millions of years.^[1] Suppose a government is deciding whether to invest in increased pensions, climate change measures, or foreign aid. According to standard longtermists, in many such decisions, the government should do whatever will have the best long-term consequences in expectation. How much these investments benefit present people, in and of itself, matters comparatively little. Instead, what’s decisive is whether they increase the chance that people (or other beings) will flourish in the very long run.

This is a very revisionary idea – if not necessarily in the actions it recommends, then at least in the justification it gives for these actions. Few of us ever consider the ramifications our choices will have a million years from now. Yet there’s an apparently simple argument for the view. The long-term future is enormous: it potentially involves astronomically many beings (human or not). Prima facie, the state of the future should morally matter to us just as much as that of the present: their sheer temporal distance shouldn’t render future beings less important to us. And it seems we can affect this far future for the better: at least some actions seem to have a higher probability than others of positively impacting it. And thus, it might seem, it’s extremely important that we act with a view to the very long term.^[2]

The question whether longtermism is true feels mesmerizing in that way characteristic of great philosophical questions. Why exactly is that? I think it’s first and foremost because the question is very important. It critically affects how we ought to think, feel, and act in many of our most momentous decisions. But not every important question is spellbinding. Whether we now ought to blow up all European hospitals is an important matter. But it isn’t very intriguing. The answer is obvious. In contrast, the question about longtermism is also difficult. Straightforward as it might look, the standard argument relies on highly controversial assumptions and concerns a whole range of issues, from the very foundations of morality to intricate empirical matters. Yet not even all important and difficult questions are bewitching in that uniquely philosophical manner. How to store nuclear waste is an important and difficult issue. But it doesn’t engender that philosophical vertigo. It doesn’t relate to the metaphysical foundations of things. The question of longtermism, however, also feels deep. It concerns the essence of our understanding of ourselves and our place in the history of the universe.

The debate about longtermism is young, but rapidly growing. It has taken various directions. Many people have explored objections to longtermism: that we’re too clueless about the far future (Mogensen 2021; Tarsney 2023), that our actions don’t relevantly affect it (Schwitzgebel 2024), that standard arguments rely on questionable assumptions about risks or demographic development (Thorstad 2024, 2023), or on a dubiously fanaticist decision theory (Kosonen 2022), that longtermism is too demanding (Mogensen 2020), doesn’t have many revisionary real-life implications (Plant 2023), is too insouciant about current problems and the current political system (Crary 2023), and thus potentially dangerous (Singer 2021; Torrs 2021), or that it threatens the integrity and meaningfulness of our lives (Riedener forthcoming). Others have discussed what some alternative normative or descriptive assumptions imply with a view to the long-term future: an obligation not to harm (Mogensen and MacAskill 2021), contractualist (Curran forthcoming) or nonadditive views (Moreno 2022; Tarsney and Thomas 2024) or the assumption of an infinite world (Tarsney and Wilkinson forthcoming). Still others have discussed practical implications of longtermist ideas: for animal ethics (Horta and Rozas 2025; O’Brien Forthcoming), equality reduction (Schmidt and Juijn 2023), for political representation (John forthcoming), or political institutions (John and MacAskill 2021; Schmidt and Barrett forthcoming). And there is of course much more material still.

Given the youth and liveliness of the debate, it is a good time for a symposium. And it seems to me that the three contributions to this symposium wonderfully illustrate why longtermism deserves our philosophical attention. Nikhil Venkatesh’s ‘Capitalism and the Very Long Term’ forcefully shows longtermism’s potential importance. Venkatesh argues that a concern for long-term welfare supports anticapitalism – at least in the weaker sense that we ought to reduce the extent to which the economy is capitalistic, and perhaps in the stronger sense that we ought to establish an alternative system in which capitalism isn’t predominant.

Venkatesh sees two main reasons for why capitalism is systematically inefficient at promoting long-term welfare. First, since future people don’t participate in present-day markets, their interests are an externality – a factor not reflected in prices. And they cannot easily be internalized, since many things that would improve long-term prospects involve present public goods (like a reduction of greenhouse gases or existential risks). Thus, long-term welfare won’t be properly incentivized in a market economy. Second, under capitalism, key investment decisions will be based on high discount rates. That’s because these decisions are often determined by the private discount rates of investors or managers, and thus ultimately by the prevailing real interest rate on the market – which is likely to be unduly high by longtermist standards. Thus again, capitalism will provide suboptimal investment in long-term welfare. A proponent of capitalism might reply that it has always contributed to growth, and thus to welfare. But Venkatesh argues that it’s uncertain to what extent capitalism actually caused growth; that such growth may not or indeed cannot continue at recent rates into the future; and that even if it does, there’s no simple correlation between growth and overall welfare.

So according to Venkatesh, considerations of long-term welfare support at least interventions like taxes on negative externalities or subsidies for positive ones – and thus reductions of capitalist structures. However, capitalists are a powerful elite and may be able to block such interventions as long as capitalism is predominant. Thus considerations of long-term welfare actually give us reason to create a system that’s predominantly noncapitalist. Venkatesh of course cannot detail an alternative economic system. But he points to the successful provision of public goods under state or cooperative systems. And he adds that noncapitalist systems may employ lower social discount rates and foster altruistic decision-making, thus improving long-term prospects.

Venkatesh’s article challenges key capitalist and longtermist paradigms. Proponents of capitalism sometimes concede that our economic system can be exploitative, alienating and inegalitarian. But they insist that at least it generates overall welfare. Venkatesh powerfully argues that, in the long term, that’s false. Longtermists, on the other hand, often adopt a relatively uncritical attitude to capitalism, or so critics have argued (see e.g. Crary 2023). Venkatesh suggests that such an attitude is flawed by their own standards.

Richard Friedrich Runge’s contribution, ‘Neo-Aristotelian Naturalism as a Metaethical Route to Virtue-Ethical Longtermism’, nicely illustrates how rich and complex, and how challenging, longtermist ideas can be. One might think longtermism simply presupposes a form of consequentialism, and collapses if one takes away that basis. But Runge argues that certain longtermist conclusions also follow from Neo-Aristotelian virtue ethics.

According to Neo-Aristotelian naturalism, as Runge understands it, whether something is good or virtuous is relative to what kind of thing it is. In particular, living things are good when they satisfy the description of their species’ life-form. Ideally, a deer doesn’t fall prey to attacking wolves. So to be a good deer is to run fast. Now Runge’s crucial original claim is that a valid description of such a life-form must satisfy a sustainability requirement: it must allow for the species’ survival under normal environmental conditions. The statement ‘a female mute swan lays a single egg in her lifetime’ cannot figure in a valid life-form description. It would necessarily result in the species’ extinction. Now for Runge, such a sustainability requirement also applies to humans and determines what it is to be a good or virtuous person. Yet our key feature is our rationality. The sustainability requirement thus determines (not so much how many children we must have or how fast we must run, but) the form of our rationality, or the kind of reasons it is responsive to: human rationality must allow for our survival in our natural habitat. Yet we humans don’t have any specific habitat. We can live under an enormous variety of circumstances, and are thus exposed to a great variety of challenges and threats. To be a good human is thus, among other things, to be disposed to recognize and respond to risks of various sorts.

Runge argues that this ultimately extends to the long-term future. If human rationality disposed us to see only to our short-term survival – or to increase long-term risks for the sake of short-term benefits – that would dramatically reduce the long-term sustainability of our life-form. So for the human life-form to be sustainable, the present generation must respond not only to existential threats affecting themselves. It may also need to address such threats affecting generations in the far future. In other words, it follows from the very essence of Neo-Aristotelian naturalism that we must act with a view to the long-term flourishing of our species.

This is a form of longtermism. But as Runge emphasizes, it’s very different from the typical longtermist view. The typical imperative is to maximize total welfare over time. Aristotelian longtermism doesn’t involve such a maximizing logic. According to Runge, by focusing on virtues and their alignment with the sustainability requirement, it offers a balanced, human-centered perspective. Runge’s article thus serves as a very valuable contribution to broaden the normative perspectives on longtermist questions, or the precise shape that longtermist conclusions can take.

Rex Lee’s paper, ‘Future People as Future Victims: An Anti-Natalist Justification of Longtermism’, in a sense illustrates the depth of longtermism, or its connection to existential questions. Lee endorses a kind of anti-natalism and argues that it grounds a form of longtermism.

Lee’s anti-natalism is based on Seana Shiffrin’s consent argument. Intuitively, it’s wrong to harm people without their consent. Yet in giving birth to a child, we expose them to life’s various physical and mental harms, without their consent. So it seems wrong to bring people into existence. In a careful discussion of this argument, Lee shows that the normative premise here is too simple. We seem permitted to harm people without their consent if doing so is necessary to prevent them from greater harm or if it’s necessary to provide them with some benefit and the harm we inflict on them is trivial or trivialized by the size of that benefit. But Lee argues that, in our world, these complications are moot. Being alive involves nontrivial harms, which are neither trivialized by the relevant benefits nor serve to prevent even greater harm. Thus it’s wrong to have children, or so he claims.

Now according to Lee, this doesn’t mean we should prohibit procreation. But it fundamentally alters our normative relation to future generations. Future people aren’t merely beneficiaries of our altruism. In bringing them into existence, we’ve wronged them. So they’re the collective victims of procreative acts by previous generations like ours. Yet they keep our economy alive and continue the projects in which we’re invested. Thus we in turn are the beneficiaries of our acts of procreation.

On this basis, Lee argues for a kind of longtermism that differs crucially from the standard quasi-utilitarian form. Consider people who will exist in the future and whose lives contain relevant harms. On the one hand, we now have stronger moral reasons to improve these people’s welfare. We don’t just have an obligation to help them (à la Peter Singer’s pond analogy). We have an obligation to compensate them for having wronged them and having benefitted from doing so (like in Thomas Pogge’s view of the global economy). On the other hand, the victim-beneficiary relation diminishes over time: in comparison to near-future generations, we’re less responsible for the suffering of very distant people and benefit less from their existence. So this implies a discount rate where our obligations towards nearer generations are stronger. However, note that the anti-natalist wrong is contingent on there being people in the future and on their lives containing relevant harms. Thus there are two ways to end the wrong of procreation. The first is human extinction. For standard longtermists this would be a disaster preventing myriads of possible people. For Lee’s anti-natalism it would be the cessation of our perpetration. Thus he thinks helping the people who will exist is lexically more important than ensuring people will exist in the first place. The second way out of the procreative predicament is the realization of a utopia where people no longer suffer and procreation is thus no longer wrong. According to Lee, that should be the underlying aim of our longtermist endeavors.

In sum, Lee shows that anti-natalism needn’t involve a disregard for future generations, as critics sometimes assume. And he illustrates how longtermism is bound up with existential questions about the value and normative status of human existence. May this symposium contribute a little bit to our understanding whether longtermism is true, or in what form it is true, and with what implications.^[3]