A Mixed Bentham-Rawls Criterion for Intergenerational Equity : Theory and Implications

Ranking development programs using integrals of discounted utilities can yield drastic consequences that offend our sense of justice. New alternative social welfare criteria should be considered. A reaction to discounted utilitarianism is to moderate its effects by adding to the social welfare function a second term that takes seriously the welfare of the generations that live in the far distant future. Chichilnisky proposes a social welfare function that has two desirable properties: (i) non-dictatorship of the present, and (ii) non-dictatorship of the future. However, in many economic models, there exists no optimal path under the Chichilnisky criterion. We introduce a third desideratum: “non-dictatorship of the least advantaged,” and propose a new welfare criterion that is morally compelling. It is a weighted average of two terms: (a) the sum of discounted utilities, and (b) the utility level of the least advantaged generation. We derive necessary conditions to characterize growth paths that satisfy our criterion, and show that in some models with familiar dynamic specifications, an optimal path exists and displays appealing characteristics.