According to the Asymmetry, we’ve strong moral reason to prevent miserable lives from coming into existence, but no moral reason to bring happy lives into existence. This procreative asymmetry is often thought to be part of commonsense morality, however theoretically puzzling it might prove to be. I argue that this is a mistake. The Asymmetry is merely prima facie intuitive, and loses its appeal on further reflection. Mature commonsense morality recognizes no fundamental procreative asymmetry. It may recognize some superficially similar theses, but we will see that they derive from more familiar principles, and are compatible with there being moral reason to bring happy lives into existence.

The Procreation Asymmetry holds that we have strong moral reasons not to create miserable people for their own sakes, but no moral reasons to create happy people for their own sakes. To defend this conjunction against an argument that it leads to inconsistency, I show how recognizing ‘creation’ as a temporally extended process allows us to revise the conjuncts in a way that preserves their intuitive force. This defense of the Procreation Asymmetry is preferable to others because it does not require us to take on controversial metaphysical or metaethical commitments – in other words, it has the theoretical virtue of portability.

This paper considers two objections based in axiological considerations against the position that whether a given outcome, or possible future or world, is morally worse than a second world may depend in part on what is going on at a third world. Such a wide-angled approach to determining worseness is critical to the solution I have previously proposed in connection with the nonidentity problem. I argue that both objections fail.

Theories of intergenerational justice are a very common and popular way to conceptualise the obligations currently living people may have to future generations. After briefly pointing out that these theories presuppose certain views about the existence, number and identity of future people, I argue that the presuppositions must themselves be ethically investigated, and that theories of intergenerational justice lack the theoretical resources to be able to do this. On that basis, I claim it is necessary to do the ‘ethics of metaphysics’ in order to fully comprehend what, if anything, we may owe future generations. I defend these claims against some important objections.

While different worries about population size are present in public debates, political philosophers often take population size as given. This paper is an attempt to formulate a Rawlsian liberal egalitarian approach to population size: does it make sense to speak of ‘too few’ or ‘too many’ people from the point of view of justice? It argues that, drawing on key features of liberal egalitarian theory, several clear constraints on demographic developments – to the extent that they are under our control – can be formulated. Based on these claims, we can clarify both the grounds and content of our obligations to future generations.

The common conception of justice as reciprocity seemingly is inapplicable to relations between non-overlapping generations. This is a challenge also to John Rawls’s theory of justice as fairness. This text responds to this by way of reinterpreting and developing Rawls’s theory. First, by examining the original position as a model, some revisions of it are shown to be wanting. Second, by drawing on the methodology of constructivism, an alternative solution is proposed: an amendment to the primary goods named ‘sustainability of values’. This revised original position lends support to intergenerational justice as fairness.

Utilitarians must think collectively about the future because many contemporary moral issues require collective responses to avoid possible future harms. But current rule utilitarianism does not accommodate the distant future. Drawing on my recent books Future People and Ethics for a Broken World, I defend a new utilitarianism whose central ethical question is: What moral code should we teach the next generation? This new theory honours utilitarianism’s past and provides the flexibility to adapt to the full range of credible futures – from futures broken by climate change to the digital, virtual and predictable futures produced by various possible technologies.

According to the relational approach we have obligations to members of future generations not because of their interests or properties but because, and only because, they are our descendants or successors. Common accounts of relational duties do not explain how we can have obligations to people who do not yet exist. In this defence of the relational approach I examine three sources of intergenerational obligations: the concern of parents for their children, including their future children; the desire of community members to pass on a heritage to their descendants; and the relationship of citizens in an intergenerational polity.

This paper explores what could be wrong with the fact of human extinction. I first present four reasons why we might consider human extinction to be wrong: (1) it would prevent millions of people from being born; (2) it would mean the loss of rational life and civilization; (3) it would cause existing people to suffer pain or death; (4) it would involve various psychological traumas. I argue that looking at the question from a contractualist perspective, only reasons (3) and (4) are admissible. I then consider what implications this limitation on reasons has for the wrongfulness of various forms of human extinction.

What moral reasons, if any, do we have to ensure the long-term survival of humanity? This article contrastively explores two answers to this question: according to the first, we should ensure the survival of humanity because we have reason to maximize the number of happy lives that are ever lived, all else equal. According to the second, seeking to sustain humanity into the future is the appropriate response to the final value of humanity itself. Along the way, the article discusses various issues in population axiology, particularly the so-called Intuition of Neutrality and John Broome’s ‘greediness objection’ to this intuition.

This paper argues that extortion is a clear threat in intergenerational relations, and that the threat is manifest in some existing proposals in climate policy and latent in some background tendencies in mainstream moral and political philosophy. The paper also claims that although some central aspects of the concern about extortion might be pursued in terms of the entitlements of future generations, this approach is likely to be incomplete. In particular, intergenerational extortion raises issues about the appropriate limits to the sway of central values such as welfare and distributive justice. We should be wary of ways in which such values invite us to buy off, or perhaps to join, an intergenerational climate Mafia.

In the Anthropocene, human beings are capable of bringing about globally catastrophic outcomes that could damage conditions for present and future human life on Earth in unprecedented ways. This paper argues that the scale and severity of these dangers justifies a new international criminal offence of ‘postericide’ that would protect present and future people against wrongfully created dangers of near extinction. Postericide is committed by intentional or reckless systematic conduct that is fit to bring about near human extinction. The paper argues that a proper understanding of the moral imperatives embodied in international criminal law shows that it ought to be expanded to incorporate a new law of postericide.

A number of philosophers have resisted impersonal explanations of our obligation to mitigate climate change, and have developed accounts according to which these obligations are explained by human rights or harm-based considerations. In this paper I argue that several of these attempts to explain our mitigation obligations without appealing to impersonal factors fail, since they either cannot account for a plausibly robust obligation to mitigate, or have implausible implications in other cases. I conclude that despite the appeal of the motivations for rejecting the appeal to impersonal factors, such factors must play a prominent role in explaining our mitigation obligations.