John Broome

This chapter surveys some of the issues that arise in policy making when the wellbeing of future generations must be taken into account. It analyses the discounting of future wellbeing, and considers whether it is permissible. It argues that the effects of policy on the number of future people should not be ignored, and it considers what is an appropriate basis for setting a value on these effects. It considers the implications of the non-identity effect for intergenerational justice and for the Pareto principle.

Since the last ice age, when ice enveloped most of the northern continents, the earth has warmed by about five degrees. Within a century, it is likely to warm by another four or five. This revolution in our climate will have immense and mostly harmful effects on the lives of people not yet born. We are inflicting this harm on our descendants by dumping greenhouse gases into the atmosphere. We can mitigate the harm a little by taking measures to control our emissions of these gases, and to adapt to the changes by, for instance, building sea walls around coastlines threatened by rising sea levels. But these measures will be very expensive, and the costs will be born by us, the present generation, whereas the benefits will come to future generations. How much should we sacrifice for the sake of the future? Economists and philosophers have independently worked on the question of our responsibility to future generations. This book brings their work together and applies it to global warming. It suggests a programme for future research on the economic and ethical issues. The book is intended for economists, and for philosophers and other social scientists who have a little knowledge of economic methods.

In 2002, Bernard Williams delivered a lecture that revisited the arguments of his article 'Ought and moral obligation', published in his Moral Luck. The lecture attributed to the earlier article the thesis that there are no ‘personal’ or (as I put it) ‘owned’ oughts. It also rejected this thesis. This paper explains the idea of an owned ought, and supports Williams’s lecture in asserting that there are owned oughts. It also examines the question of how accurately Williams’s later lecture interprets his earlier article.

Most properties have comparatives, which are relations. For instance, the property of width has the comparative relation denoted by `_ is wider than _'. Let us say a property is reducible to its comparative if any statement that refers to the property has the same meaning as another statement that refers to the comparative instead. Width is not reducible to its comparative. To be sure, many statements that refer to width are reducible: for instance, `The Mississippi is wide' means the same as `The Mississippi is wider than most rivers'. But some statements that refer to width are not reducible: for instance, `Electrons have zero width' is not. A property is not reducible to its comparative if it has absolute degrees, and specifically an absolute zero. A property's comparative relation places things in an order from those that have the property least to those that have it most. If there is an absolute zero point somewhere in this ordering, the property is not reducible to its comparative. For width, there is an absolute zero at one end of the ordering, so width is not reducible. The property of goodness is reducible to its comparative, betterness. In particular, there is no absolute zero of goodness. Things are ordered by betterness – some things are better than others – but nothing is absolutely good or absolutely bad. This is an exaggeration. In certain applications, goodness does have absolute degrees of a sort, and an absolute zero. For instance, it makes sense to say an event is good, and another event bad. These are absolute degrees of a sort, but they are themselves reducible to betterness. To say an event is good simply means the event is better than what would otherwise have happened. The goodness of lives has a different sort of absolute zero. Lives are ordered by betterness; some lives are better than others. We can make sense of the question `Where in this ordering is the division between lives that are good and those that are bad?' The division between good and bad lives is again reducible to betterness. To say a person's life is good means it is better that the person should continue living, rather than that she should die. Or it may mean it is better that her life should be lived rather than that it should never have been lived at all. As it is often put: a good life is a life worth living. Derek Parfit appears to attach a different sense to the idea of a good life. He appears to mean a life that contains a preponderance of good things (such as pleasure) over bad things (such as pain). If a life contains no good things and no bad things, it has zero goodness in this sense. In this sense, absolute goodness and the absolute zero of goodness are not reducible to betterness. However, this is a naturalistic sense of goodness, and it is subject to the open-question objection. If a life contains no good things and no bad things, it is an open question whether it has zero goodness. It might, for instance, be a bad thing that this life should be lived. In discussing the evil of death, some philosophers seem to have been searching for an absolute goodness that is not reducible to betterness. Thomas Nagel speaks of an asymmetry between what is good about life and what is bad about death. But if a person's life is good, that only means it would be better that she should continue living than that she should die. And if a person's death would be bad, that only means it would be worse that she should die than that she should continue living. So there can be no asymmetry.

Rationality requires various things of you. For example, it requires you not to have contradictory beliefs, and to intend what you believe is a necessary means to an end that you intend. Suppose rationality requires you to F. Does this fact constitute a reason for you to F? Does it even follow from this fact that you have a reason to F? I examine these questions and reach a sceptical conclusion about them. I can find no satisfactory argument to show that either has the answer ‘yes’. I consider the idea that rationality is normative for instrumental reasons, because it helps you to achieve some of the things you ought to achieve. I also consider the idea that rationality consists in responding correctly to reasons. I reject both.

Esteemed philosopher John Broome avoids the familiar ideological stances on climate change policy and examines the issue through an invigorating new lens. As he considers the moral dimensions of climate change, he reasons clearly through what universal standards of goodness and justice require of us, both as citizens and as governments. His conclusions—some as demanding as they are logical—will challenge and enlighten. Eco-conscious readers may be surprised to hear they have a duty to offset all their carbon emissions, while policy makers will grapple with Broome’s analysis of what if anything is owed to future generations. From the science of greenhouse gases to the intricate logic of cap and trade, Broome reveals how the principles that underlie everyday decision making also provide simple and effective ideas for confronting climate change. Climate Matters is an essential contribution to one of the paramount issues of our time.

Reasoning is a process through which premise-attitudes give rise to a conclusion-attitude. When you reason actively you operate on the propositions that are the contents of your premise-attitudes, following a rule, to derive a new proposition that is the content of your conclusion-attitude. It may seem that, when you follow a rule, you must, at least implicitly, have the normative belief that you ought to comply with the rule, which guides you to comply. But I argue that to follow a rule is to manifest a particular sort of disposition, which can be interpreted as an intention. An intention is itself a guiding disposition. It can guide you to comply with a rule, and no normative belief is required