In Death and the Afterlife, Samuel Scheffler argues that it matters greatly to us that humanity continues after we are gone, and that it continues to flourish. Human extinction would undercut our capacity to lead value-laden lives to a very large extent. Why Worry About Future Generations is very much the sequel. It explores and elaborates the reasons that this analysis gives about the importance to care for how future generations fare.

What distinguishes Scheffler's book from most other works in the rapidly expanding philosophical literature on future generations is that Scheffler's analysis of our reasons to care for future generations is not primarily cast in moral terms. We are not offered an account of what we owe to future generations, or what kind of world it would be best to bring about. Rather, Scheffler renders the reasons that most of us already have for caring about future generations explicit by examining the way future generations relate to our values and attachments. In effect, Scheffler claims that we have strong non-moral normative reasons to want future generations to exist and flourish (p. 135).

Scheffler distinguishes four different reasons to care about future generations: reasons of interest, reasons of love, reasons of valuation and reasons of reciprocity. First, we have reasons of self-interest to care for future generations. Many of the activities people consider valuable acquire this value because they extend into the future. If we knew that humanity would cease to exist after we die, many activities would lose their point. That these activities would lose their value is not only bad because it is the loss of something valuable, but it is against our interest. Scheffler gives three examples. First, long-term projects are often part of bigger valuable processes, such as medical research, allowing for a meaningful connection between individuals and the collective. Second, we aim to preserve and enrich human heritage and cultural practices, both for ourselves and for future generations. Third, being a part of life-transcending projects help us make sense of our world, they help us ‘think better – more creatively, more insightfully, more imaginatively – about human societies and the possibilities open to them' (p. 51). In contrast, without the possibility of life-transcending projects our capacity to lead value-laden lives would considerably diminish (p. 54).

Reasons of interest are not, Scheffler emphasizes, exhaustive. If humanity ended this would cause a heartfelt shock, sadness and a sense of loss within current generations, and not just because our long-term projects would be cut short. Our shock rather illustrates a genuine concern for future generations and the fate of humanity in its own right (p. 55). We would not feel sad about the loss of something that we did not genuinely care about. Moreover, many people ‘believe it is worth devoting their lives to activities whose greatest benefits may not be realized until after they are gone' (p. 56). If we did not care about humanity in its own right, why would we assign such a prominent place to life-transcending projects in the first place? Our desire that the chain of human generations continues, in conditions conducive to its flourishing, reveals the second reason to care about future generations, love of humanity (p. 62).

Third, the disappearance of humanity would entail the disappearance of the things we value, and even the act of valuing itself (p. 70). Works of art, traditions and human relationships would all, eventually, cease to exist. This affects us, because all the things we currently value will disappear and no new things of value will be brought into existence (p. 69). Because we cannot value something without simultaneously caring about its preservation, we need to safeguard the existence of future generations if we want to preserve the things we value. As Scheffler puts it: “the future of humanity is the future of value” (p. 70). These are reasons of valuation.

Fourth, we have reasons of reciprocity to care about future generations. Future generations are usually presented as being dependent on us. We can act in ways that affect the conditions in which they will live, but they cannot affect the past. Nevertheless, Scheffler thinks we can meaningfully speak of intergenerational reciprocity (p. 75) in two ways: their survival is a precondition for our activities being, and being confidently judged, valuable (evaluative dependency), and ‘their immanent disappearance would be profoundly distressing to us’ (p. 73) (emotional dependency). We do not depend on future generations in the same way as they depend on us, but there is mutual dependency nonetheless. How this dependency gives raise to reasons of reciprocity of a non-moral kind (p. 79) remains a bit elusive. The crux is that those who are moved by reciprocity in general will be moved by this sufficiently similar kind of mutual dependency as well (p. 77), but one could question whether those who are moved by reasons of reciprocity in more usual cases are not moved, at least partially, by moral reasons.

It is not always entirely clear – as Scheffler acknowledges – how these four reasons hang together precisely: are they separate reasons converging on one conclusion, or are they perhaps reduceable to each other? Reasons of love are, arguably, fundamental. We have reasons of interest and valuation in no small part because we invest ourselves in projects that transcend our own existence, and this reveals we already care about what happens. We are evaluatively and emotionally dependent on future people – creating evaluative reciprocity – because we have such life-transcending projects and because we care about their survival. As Scheffler writes: “If the survival of human beings did not already matter to us, we would not have as great an interest in trying to ensure it.” If love for humanity would indeed be foundational, this raises the question of whether we are correct in valuing humanity, and why. This might be a lack of imagination on our part, but we are not certain this question can be answered without an appeal to any moral commitments.

Scheffler argues that all four reasons are attachment-based: they are informed by our concern for existing things that we already value. That is why “[a] conservative disposition to preserve and sustain the things that we value is built into our valuing attitudes” (p. 89). We want to protect future generations because we want to preserve what we value. In so far as we are right to value the things we value, we have reasons to do so. Hence, in addition to having attachment-based reasons, we also have weaker, attachment-independent reasons (p. 97) to protect future generations. Scheffler contrasts this view with beneficence-based approaches, which he takes to be the most prominent alternative, but which focus primarily on impersonal reasons (i.e. bringing out the best state of the world). Such principles can only provide us with impersonal reasons to care about and value future generations, whereas Scheffler denies that the intrinsic value of something alone is reason to create more of it – we need to value it as well. This is also why temporal neutrality is a vice of the beneficence-based approach: we are attached to the things we now value, not to the things that – no matter how valuable they would objectively be – could exist (p. 135).

Scheffler denies that in order to establish attachment-independent reasons a population axiology is required – allowing us to rank different states of the world in terms of goodness – in order to acknowledge the value of humanity. However, we cannot escape the impression that he – implicitly – relies on a minimal non-utilitarian axiology. He claims that we have attachment-independent reasons to care about future generations, which follow from our reasons of love and which may be ‘reasons to ensure that the chain of human generations is extended into the indefinite future under conditions of human flourishing' (p. 102). This entails a ranking of states of affairs. A world in which humans continue to flourish is better than one in which they do not. It implies, perhaps, indifference about numbers, i.e. it does not matter how many people there are, as long as they flourish. Perhaps Scheffler would refuse the label ‘axiology' for these commitments, but given that it entails a ranking there seems less distance between the axiological project and Scheffler's project than he suggests.

Scheffler's analysis invites a host of other questions and puzzles, but let us end with two questions about the project as a whole. The first concerns Scheffler's attempt to make moral reasons to care about future generations less central. To be sure, Scheffler does not deny that there might be moral reasons, beneficence-based or other, to care for future generations. And we agree that focusing just on moralized reasons alone would be unduly narrow (e.g. p. 37). But the question his discussion raises is how important these non-moral reasons are in our overall set of reasons to care about future generations. Imagine someone making the parallel point about reasons for preventing global poverty, and offering an elaborate story to explain why we – say, the inhabitants of wealthy countries – have non-moral reasons originating in the structure of our evaluative thought. They would, probably, be right in pointing out we have such reasons. But these reasons will all be relatively trivial compared to the reasons that the badness and wrongness of poverty itself give us to act. Similarly, the conviction that it is wrong or bad to create a world in which people lead miserable lives is what drives much of the writing on population ethics and intergenerational justice.

The reasons Scheffler uncovers are – in the way that he presents them – firmly embedded in the realm of the ‘good’. Although our interests are in many cases other-regarding, we do not have other-regarding obligations to act on these other-regarding reasons. These reasons, then, apart from being relatively trivial, are easily defeasible. If this is right, the choice to focus on moralized discourse is much less surprising given the important role that moral reasons play in our overall reasons for action. All of this of course does not mean that Scheffler is wrong, but the first virtue of uncovering the future-oriented nature of our value-structure may very well be primarily motivational. How welcome this motivational force is depends partially on whether we think we have strong moral reasons to avoid certain outcomes (such as human extinction or future human misery). The second virtue of Scheffler's account, of course, is that the reasons he gives are immune to the population puzzles with which moral theories are faced. He can give reasons to care regardless of whether a satisfactory solution to these puzzles can be found, which at least serves as a second line of defence against (intuitively unappealing) indifference about the plight of future generations.

A second question that Scheffler's work raises is whether the reasons he unveils have no moral force at all. It seems to us that, for example, the view has possible implications for obligations of justice to contemporaries. We – members of current generations – need there to be future generations (and for them to flourish) in order to avoid a serious setback in our capacity to lead value-laden lives. In so far as we think that justice requires that we protect peoples’ capacity to realize their conceptions of the good life, it seems to follow that we owe it to our contemporaries to care for future generations. This move would place the reasons Scheffler provides much more at the core of our reasons to act. They would not be reasons to think that we owe anything to future people, but they would ground obligations regarding future people (e.g. Gosseries, On Future Generations’ Future Rights, 2008).

If we have one serious misgiving about the book (and its predecessor), it is that it almost completely fails to engage with other scholarly work on its central question (see, for an excellent overview of previous literature, Davidson's review of Death and the Afterlife, 2015). This might create the impression that Scheffler has opened a new field of inquiry, whereas most of the ideas Scheffler presents have been discussed in detail. It would be a real loss if people new to these questions followed Scheffler in neglecting earlier work, for example David Heyd's remarkable Genethics (1992).

This book presents a compelling case that we have many reasons to worry about future generations, and points to further fascinating questions about the role future generations play in our moral and ethical lives. The force of these arguments is that they do not appeal to abstract or complicated moral systems but embed these reasons in the structure of our – at least widely shared – evaluative attitudes. Strategically, this is an important contribution given the kind of challenges which face humanity. That alone is reason enough to hope that the book will be widely read.