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John Broome

Climate Matters: Ethics in a Warming WorldNew York and London: W. W. Norton & Company, 2012. 210 p. $23.95.

The eminent Australian economist Ross Garnaut has aptly described anthropogenic climate change as a diabolical problem. It involves an enormous number of social and physical processes, requires integrated analysis across a wide range of spatial and temporal scales, and raises profound political and moral issues. The lack of consen-sus about how to respond is attributable not only to conflict over vested interests, but also to disagreement over the facts of the case and an absence of shared moral principles for choosing appropriate ends and means. Climate science has made mas-sive strides during the last 20 years, and the scientific findings receive considerable public attention. Public debate on the ethics of climate change, by comparison, is poorly articulated and lacks positive momentum. Enter John Broome, the White’s Professor of Moral Philosophy at Oxford University, with Climate Matters in hand: “In this book, I do not claim to give you definitively correct views about the morality of climate change. Instead, I hope to give you materials for thinking through issues of climate change for yourself” (p. 9). What are these materials, and how helpful might they be for concerned citizens?

First, the materials. Broome’s main analytical approach is an extended version of cost–benefit analysis. “Comparing costs and benefits means comparing values. It means weighing the good that can be achieved by some project … against the badness of its costs and risks. Values underlie all the calculations of costs and benefits that economists engage in.… Values arise from moral principles” (p. 9). A central moral issue regarding greenhouse gas (GHG) emissions is that the people responsible for their release into the atmosphere gain benefits at the same time as they cause harm to others without paying compensation. This benefiting by some (the emitters) from externalities at the expense of others (the receivers) constitutes an injustice. Broome shows that simply asserting that the morally responsible alternative is that the emit-ters should pay the full cost of their actions is not enough to resolve the issue, because the costs of this action are primarily borne by those living today while many of the benefits (or reduced harms) will only be enjoyed by future generations. Weighing the costs and benefits in this case requires that we in effect compare the value of lives lived today with the value of lives of those not yet born, not an easy undertaking. Arguments like these show that cost–benefit analysis inevitably involves an element of weighing the moral values associated with alternative outcomes, not just monetary values, and Broome shows this is the case a fortiori with global climate change, since it involves weighing costs and benefits across many social, spatial, and temporal scales. He concludes we need “cost–benefit analysis founded on moral principles” (p. 48), and he takes this desideratum to his analysis of climate issues.

“When you cause emissions, they harm other people. This is an injustice done to those people, and it also makes the world worse. So reducing emissions is a duty of justice and also a duty of goodness” (p. 53). The main body of the book comprises one chapter on the relevant duty of justice (primarily a matter of private morality for individuals) and four chapters on the duty of goodness (primarily a matter of public morality for governments). In the case of climate change the duty of goodness does not demand much of the individual emitter, since reducing his emissions to zero would have a negligible effect on improving the world, and there are probably more

©2014 The Population Council, Inc.

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efficient ways for him to improve the world with whatever resources are available. His duty of justice, however, is a different matter: “Duties of justice are owed by one person to another particular person, or to other particular people” (p. 52). Our emitter’s GHG emissions will contribute some harm to someone; his duty of justice therefore requires that he either cut his emissions or pay compensation. Broome’s conclusion is that our emitter can satisfy his duty of justice by buying offsets. Given the widely publicized problems with verifying claims of protecting forests under REDD+ schemes* and the like, this conclusion will strike many as unduly sanguine, but to be fair to Broome he gives a reasoned account of pros and cons even if he does not review any relevant empirical data.

The chapters on goodness deal with four specific issues about values, namely, responding to uncertainty, comparing harms and benefits widely separated in time, how to set value on human lives, and population. To deal with uncertainty, Broome advocates the use of expected value theory: “The expectation of harm caused by a catastrophe is the badness of the catastrophe multiplied by the very small probability that it will happen” (p. 131). Calculating the small probability is a matter for science, but what about calculating the badness of, say, the extinction of humanity? This, says Broome, “is a task for moral philosophy” and a reason why “we must continue with developing the theory of value” (p. 132). The chapter on how to weigh the benefits of future well-being associated with reducing emissions against the costs of sacrific-ing present well-being examines the ethics of discount rates. Broome’s conclusion is that although there are excellent reasons to discount future commodities, “we should count well-being as equally valuable whenever it occurs” (p. 155). This would be a powerful conclusion if we had an agreed metric of well-being. In the chapter discussing the value of human lives, Broome notes that “money is nearly always a bad measure of value, not just for lives but for anything” (p. 165). Given the present state of practical cost–benefit analysis, we cannot aggregate the value of lives with the value of other goods in any satisfactory way; this, Broome acknowledges, leaves “a large hole in the cost–benefit analysis of climate change” (p. 166).

Readers of PDR may be especially interested in Broome’s last chapter, addressing population. Future climate change and future population growth are interrelated. Therefore evaluating alternative climate actions using cost–benefit analysis based on moral principles requires that we compare the values associated with alterna-tive population scenarios. In this connection, however, Broome alleges most people have a false intuition: “The intuition is that, when something changes in the world, we can evaluate the change on the basis of how good it is for the people who exist; we can ignore people who are added to the population as a result of the change” (p. 171). He refutes the intuition by showing how when applied to a comparison of well-being among three hypothetical population outcomes it produces a falsehood. He concludes, “Global warming will alter the population, and so will whatever response we make to global warming. We cannot assume this effect on population is morally neutral” (p. 175); therefore “we have work to do in moral philosophy in setting a value on the loss of population” (p. 183).

I doubt many population experts will find this chapter enlightening. With all the difficult population-and-development problems facing the world today, trying to set values to lives that might have been born one or two generations hence had

*REDD+ = reducing emissions from deforestation and forest degradation plus enhancement of forest stocks.

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births not been averted through family planning or potential parents lost through some catastrophe resulting from climate change will strike many as little more than a scholastic abstraction.

How useful are the materials presented by Broome for thinking through the moral issues posed by anthropogenic climate change? My own thinking has without question been challenged by this book, but I believe two of its features will limit its overall utility. First, Broome’s single-minded commitment to a cost–benefit frame-work restricts the range of moral issues discussed. Climate Matters builds on his earlier research, especially Weighing Goods (1991) and Weighing Lives (2004). His justifica-tion for using this perspective in relation to climate change is that governments are already using an economic framework in fashioning their responses, so the relevant moral problems arise within this context (p. 37). However, many environmentalists and other commentators regard the prevailing privileging of conventional econom-ics in responding to climate change (and to other sustainable development issues) as itself part of the problem. A growing number of critics argue for a new model of ecological economics that makes explicit the way our material economy is embedded in society, and the way this in turn is embedded in (and dependent on) our ecological life-support systems (e.g., Costanza et al. 2013). Broome’s commitment to a more conventional model means some of the more important issues that many commenta-tors now see as associated with climate change—man’s responsibility toward nature, the value of biodiversity, the rights of non-human species—are not discussed.

A second limitation is, I believe, the result of Broome’s expository style. Broome seems so intent on keeping his exposition simple and conversational, presumably believing this will ensure the work is accessible to a broad audience, that it becomes burdened by repetition, vague illustrations, and misleading caricatures and anec-dotes. Most importantly, the structure of the argumentation is not always clear. When Broome writes a declarative statement such as, “Values arise from moral principles” (p. 9), we are not sure whether to interpret this as a statement of fact, an assump-tion, or even perhaps as a contentious hypothesis among moral philosophers put forth by Broome to distinguish his approach from that of others. Few of the terms used in the book are clearly defined. The book includes an introductory chapter on climate change and another on economics, but strangely not one on ethics or moral philosophy. It is hard for the non-specialist to figure out where Broome’s “total utili-tarianism” (p. 173) sits in the philosophical landscape. Simplicity has been bought at the expense of precision and transparency.

In sum, this book will be provocative for anyone interested in the ethics of climate change, but it fails to demonstrate that the approach it advocates is either adequate or the best available when trying to make moral sense of this particular existential threat.

Australian Demographic and Social Research Institute adrian C. hayes Australian National University

Reference

Costanza, Robert et al. 2013. “Building a sustainable and desirable economy-in-society-in-nature,” in State of the World 2013: Is Sustainability Still Possible? Washington, DC: Island Press, pp. 126–142.