a1 University of Wisconsin-Madison
a2 Spencer Foundation
The tenuous claims of cost-benefit analysis to guide policy so as to promote welfare turn on measuring welfare by preference satisfaction and taking willingness-to-pay to indicate preferences. Yet it is obvious that people's preferences are not always self-interested and that false beliefs may lead people to prefer what is worse for them even when people are self-interested. So welfare is not preference satisfaction, and hence it appears that cost-benefit analysis and welfare economics in general rely on a mistaken theory of well-being. This essay explores the difficulties, criticizes standard defences of welfare economics, and then offers a new partial defence that maintains that welfare economics is independent of any philosophical theory of well-being. Welfare economics requires nothing more than an evidential connection between preference and welfare: in circumstances in which people are concerned with their own interests and reasonably good judges of what will serve their interests, their preferences will be reliable indicators of what is good for them.
Although organized and expressed quite differently, many of the ideas of this paper can be found in chapter 4 of our Economic Analysis, Moral Philosophy, and Public Policy. During the long period in which the ideas here germinated, many readers and audiences have helped us, and we are no longer able to acknowledge all these helpers individually, apart from Philippe Mongin, who gave us insightful suggestions on the penultimate draft.