Normative ethics – including what is usually referred to as ‘applied ethics’ – indisputably constitute one of the largest areas of growth in modern philosophy. The number of topics dealt with has exploded and each sub-area of the field has undergone a major degree of specialization. Those theorists and positions regarded as the most prominent in one field may be totally unknown to theorists working within another of the various sub-disciplines of ethics. A major expansion and specialization has also taken place in the field usually referred to as population ethics.
The first collective work published within this field – reflecting the then ongoing or at least incipient discussions – was Obligations to Future Generations edited by Sikora and Barry in 1978. This work dealt with questions such as whether the present generation has moral obligations towards future ones and touched on newly acknowledged challenges such as the non-identity problem and the repugnant conclusion. Discussion of these new challenges has over the years become more elaborate and sophisticated. The various challenges have each been dealt with in more specialized collective and single-authored works.
The most recent work within the field – Intergenerational Justice edited by Gosseries and Meyer – in one sense reflects the current developments within the field; in another sense it does not. On the one hand, the contributors are all of course informed by the modern literature in the population ethical field. On the other, the editors have not picked out one of many narrow challenges in order to subject it to new and more specialized attention. Rather they have decided to focus on what constitutes an overall but pivotal question in the field – namely, intergenerational justice – in order to submit it to more detailed analyses and discussions. The result is a comprehensive work that will be useful to all scholars with an interest in modern population ethics.
The structure of the work is simple. The first section presents various interpretations of intergenerational justice from the perspective of most of the broad theoretical accounts of justice in modern political philosophy. The second section is devoted to a number of more specific issues which in one way or another relate to intergenerational justice.
The opening chapter is written by Janna Thompson. As her point of departure, she holds that nations are best described as a ‘transgenerational polity: a society in which generations are bound together in relationships of obligation and entitlement’ and that theories of justice ‘ought to reflect the importance to citizens, and to the nature and operation of their society, of transgenerational relationships’ (p. 26). Moreover, she contends that liberal theories generally fail to do this. What she offers instead is a weak communitarian perspective based on the idea of ‘life-transcending interests’ which leads to the conclusion that there exist obligations to the past as well as to the future.
In contrast to Thompson's communitarian analysis, the subsequent chapter is devoted to considerations within a libertarian framework. The authors – Hillel Steiner and Peter Vallentyne – sketch the outlines of libertarian views on intergenerational justice. More precisely, they explore what a Lockean proviso – the condition that ‘enough and as good’ be left for others – implies within the intergenerational context. Assuming that a plausible version of libertarianism will invoke a proviso on both use and appropriation, the authors examine what form such a proviso should take.
In the third chapter, attention is directed to contract theory. As Stephen Gardiner initially explains – quoting Stephen Darwall – contract theories seek to justify moral and political ideals and principles through the notion of mutually agreeable reciprocity of cooperation between equals. However, this basic idea of contract theory faces problems when applied within an intergenerational setting. After having introduced two standard approaches to contract theory, Gardiner outlines three challenges – the rationale challenge, the structural challenge and the justification challenge – each confronting the application of such theories to an intergenerational setting. He then considers to what extent traditional contract theory succeeds in dealing with the outlined challenges. Gardiner ends his discussion by briefly considering the possibility of an alternative, more universal, version of contract theory.
The discussion by Gardiner nicely leads on to an exploration by Axel Gosseries of the idea of intergenerational reciprocity. Gosseries distinguishes between three different models of intergenerational reciprocity. He asks to what extent the models are affected by Brian Barry's question, namely, why the fact of having received something from others justifies an obligation falling on the receiver to give something in return. While it is argued that Barry's objection is not decisive, it is suggested that demographic fluctuations from one generation to the next in different ways constitute serious difficulties for the three models. None of the models manages to adequately deal with the question of how changes in the size of a population affect reciprocity-based accounts of intergenerational obligations.
The contribution by Christopher Bertram addresses a somewhat different topic which is held to constitute a particular aspect of injustice, namely exploitation. The question that Bertram brings into consideration is whether it is possible for a generation at one time to exploit a generation at another. That the answer is in the affirmative in cases where generations overlap is not surprising. Bertram's aim, however, is to make plausible the idea that people at one time can exploit people at another, even when we are considering non-overlapping generations.
The subsequent two contributions – chapters six and seven – are dedicated more narrowly to an analysis and discussion of Rawls’ understanding of intergenerational issues. Heyd considers various attempts at designing the original position in an intergenerational setting. While Attas, for his part, takes up the challenge of designing the original position in such a way that mutuality relations obtain in that situation, even though such relations between earlier and future generations do not exist in the real world. Moreover, in contrast to Heyd's interpretation, Attas urges an understanding of the ‘just saving principle’, not as an external constraint limiting the application of Rawls’ difference principle, but ‘as a clause in its full articulation’ (p. 216).
The final contribution represents yet another theoretical position in modern political philosophy. Lukas Meyer and Dominic Roser distinguish between egalitarian positions and a sufficientarian position according to which what matters is that everybody is well-off, that is, has well-being above a certain threshold which is considered sufficient. What the two authors argue is that there are strong reasons for interpreting intergenerational justice in terms of a sufficientarian conception of justice.
While the first section of the book is devoted to discussions of the applicability and challenges of various theories of justice to an intergenerational context, the following section, as mentioned, addresses various narrower issues to which considerations on intergenerational justice give rise.
Rahul Kumar opens the section by proposing that a traditional way of framing intergenerational obligations in impersonal terms is set in favour of an interpersonal characterization of such obligations. More precisely, it is suggested that such obligations should be analysed in terms of Scanlonian contractualism. This contractualist position offers an explication of an interpersonal sense of ‘moral wrong’ according to which ‘A wrongs B by failing to give B the kind of deliberative consideration of her relevant interests to which she is entitled, where what she is entitled to expect by way of consideration is fixed by a relevant principle for the general regulation of the type of situation that no one can reasonably reject’ (p. 254). In contrast to the Rawlsian contractualist account of justice, the notion of social co-operation or reciprocity plays no role in the suggested account. However, what Kumar argues is that on the contractualist account of wronging, the non-identity problem cannot get started in the first place. Moreover, it follows that, given contractualism, the reason we have to be concerned about avoiding wronging those who will live in the future is no different from the reason we each have to be concerned with not wronging those now living.
The following contribution by Dieter Birnbacher addresses what the author refers to as the ‘motivation problem’, that is, the general problem of bridging the psychological gap between the acceptance of a rule and acting in accordance with it. This problem constitutes an obvious challenge in relation to considerations of intergenerational justice; especially in relation to obligations to the more distant future. What Birnbacher suggests is that indirect sources of motivation can lead us to act in accordance with requirements of intergenerational justice.
Another challenge concerns desire-based theories of well-being. Krister Bykvist, in his contribution, shows that desire-based theories are threatened by indeterminacy in the sense that in some cases there is no determinate answer to the question of which preferences it is best to inculcate in a person. And even if this is not the case, the theory still faces problems of inconsistency. What Bykvist ends up advocating is a desire-theory that defines well-being in terms of desires that match up with objective values.
The paradoxical nature of population ethics has, since Derek Parfit first presented his pioneering work in the field, constituted a focal point in the academic discussion. While population paradoxes have not been addressed in the former chapters, they are taken up in the contribution by Gustaf Arrhenius. The question he raises is whether egalitarian concerns can help solve Parfit's famous Mere Addition Paradox. Although it seems that the answer is in the affirmative, it is nevertheless shown that another paradox remains unresolved. Arrhenius ends up noting that theories regarding moral duties to future generations are still ‘on shaky ground’ (p. 343).
The ensuing contribution, like the first of the volume, addresses an issue of obvious relevance in relation to intergenerational justice, namely, climate changes. Clark Wolf offers an account of justice that provides guidance in circumstances where present choices will influence the intertemporal distribution of burdens and benefits as they do in the case of climate policy. The suggested theory – drawing on the work of Rawls – is then applied to the special problems presented by global environment changes.
The final contribution raises the question as to what normatively binding force does a constitution, if discussed, negotiated and approved by citizens who are contemporaries, retain for future generations who took no part in its discussion, negotiation and approval. The author – Victor M. Muniz-Fraticelli – lays out and critically discusses Thomas Jeffersons’ and Michael Otsuka's voluntarist arguments against a perpetual constitution. The chapter ends by defending the legitimacy of a perpetual constitution, on the grounds of instrumental, normative and ontological reasons.
As this brief outline hopefully indicates, the second section of the book – as is the case with the first – has very much to offer in terms of analyses of some of the theoretical challenges that arise within an intergenerational context. The comprehensiveness of the work makes one wonder whether the editors should have produced two books rather than one. With the addition of a few more chapters, supplementing the contents of the first section, one would have a volume devoted more narrowly to the interesting question of the applicability of various traditional theories of justice within an intergenerational setting. Also, it would be no problem to supplement the second section with other special issues thereby leaving sufficient material for a second volume. However, this purely editorial comment in no way changes the fact that the book constitutes a very significant contribution to an overall topic which – due to the fact that it is both theoretically challenging and practically highly pertinent – seems destined to constitute a continuously expanding sub-field of ethics.
