J. Paul Kelleher's "The Social Cost of Carbon"

J. Paul Kelleher is an Associate Professor of Bioethics and Philosophy at the University of Wisconsin–Madison.

His research and teaching explore ethical and other philosophical dimensions of public policy, especially climate policy and health policy.

Kelleher applied the “Page 99 Test” to his new book, The Social Cost of Carbon: Ethics and the Limits of Climate Change Economics, and reported the following:

If readers opened my book to page 99 they would definitely get a good feel for the thing as a whole. They would quickly see that the book is technical and not an easy read for the layperson. I realize this admission is not going to help me sell books, but I also believe in full disclosure! Still, even the uninitiated reader can get a good sense of the book's motivations and aims by reading its accessible and short stage-setting preface, the preprint version of which is available here.

Page 99 of the book has me discussing an important topic in climate change economics, namely the "pure time discount rate." Evaluative economic models of climate change typically assume that if a benefit or harm will come later in time, it is for that reason less worth caring about than if it would be experienced today. Page 99 considers one of the arguments for holding this view, an argument concerning uncertainty. Later in chapter 5 I provide a much longer discussion of pure time discounting in climate change economics and in welfare economics more generally.

After that discussion of pure time discounting, page 99 also kicks off my explanation and analysis of a very important theorem of welfare economics, John Harsanyi's Aggregation Theorem. (Harsanyi won the Nobel Prize in economics in 1994, but for work done in another area of economics.) Harsanyi's theorem provides an axiomatic basis for broadly utilitarian welfare economics, which is the economic framework that underpins many evaluations of climate change policy. But most climate economists do not draw on Harsanyi's theorem. If they give any consideration at all to the theoretical foundations of their models, they are likely to invoke distinct utilitarian theorems that I analyze elsewhere in the book. The discussion that begins on page 99 ends with my commending Harsanyi's theorem to climate economists. I think it is the proper foundation for evaluative climate change economics, and the book as a whole argues for this.

Visit J. Paul Kelleher's website.

--Marshal Zeringue