Unless something goes drastically wrong in the next few centuries, most of the people who will ever live are yet to be born. Our actions have little impact on those who are dead, considerable impact on those currently alive, and potentially enormous impact on those who will live in the future. Our decisions affect who those future people will be, and even if there will be any future people at all. The threat of environmental crisis gives us some inkling of the magnitude of our impact on future generations. Only in the last few decades have moral philosophers really begun to grapple with the complexities of intergenerational ethics. Underlying their often technical debates are some of the deepest moral questions. What makes life worth living? What do we owe to our descendants? How do we balance their needs against our own?Philosophical discussion of intergenerational ethics focuses on ways that our relations with future people differ from relations between contemporaries. There is only a distinct subject if there is a distinctive subject matter. One difference is that, while everyday decisions impact on other people, only in intergenerational ethics do our decisions affect who will begin to exist -and how many people will begin to exist. Different population or family planning policies bring different sets of people -and different numbers of people -into existence.A related feature of intergenerational ethics is a stark lack of reciprocity. While our decisions affect the lives of future people, their actions have no impact on us. We can do a great deal for (or to) posterity, but posterity cannot do anything for (or to) us. If we think of morality as a bargain or contract, then it seems we have no obligations to future people at all.These distinctive features of intergenerational ethics raise three central questions: (1) Do we have any obligations to future people? (2) If so, what grounds those obligations? (3) Finally, what obligations do we have? While the third question is clearly the most urgent from a practical point of view, most philosophical attention has focused on the first two questions. This essay examines the two dominant traditions: utilitarianism and social contract. It first asks why intergenerational ethics is such a recent subject.
Why Did Philosophers Ignore the Future?Until very recently, moral philosophy concentrated on interactions between contemporaries. Future generations were only ever an afterthought. To see why, we first distinguish three general sets of background assumptions one might bring to the study of intergenerational ethics.