Intergenerational Justice and Sustainability Under the Leximin Ethic

Let me begin by proposing that we think about intergenerational justice from the viewpoint of equality of opportunity. According to the equal-opportunity view, a person should be compensated if his welfare is low due to circumstances beyond his control, but not if it is low due to actions or choices that we (our society) thinks he should be held responsible for. The word I use to denote the second set of actions/choices is ‘effort’. Consider, now, a standard economic growth model with a representative agent at each generation. The society consists of the set of all agents who will ever live, one representing each generation. Clearly, the pre-eminent circumstance, for an individual in this society, is the date at which he is born. So if we apply the equal-opportunity view, and if we assume that individuals are identical except for their birthdates, we would have to say that justice requires an intertemporal resource allocation which enables all individuals, regardless of their date of birth, to acquire the same level of welfare. We must, however, be interested in efficiency as well as equity, so the just and efficient allocation of resources is that one which enables all individuals, regardless of their birth date, to achieve the same level of welfare, where that level is the highest possible such level. Even this, however, may not be Pareto efficient — it may be possible to render all individuals (weakly) better off than at that any equal-welfare distribution. And so we finally say that the just and efficient allocation of resources is that one which renders the worst-off representative agent (across generations) as well off as possible: the intergenerational maximin distribution.