Suppose that there exists a positive (exogenous) probability that at each date of a possibly infinite future, the human species will disappear. We postulate an Ethical Observer (EO) who must solve an intertemporal welfare maximization problem under this kind of uncertainty, with preferences that...

We model an intergenerational society, with a representative agent at each date, who must deplete a renewable resource, from which he derives utility, to produce consumption goods. We adopt the intergenerational lexicographic minimum as the social welfare function. Initially, technological...

Sustainability has been largely replaced by discounted utilitarianism in contemporary climate-change economics. Our approach rejuvenates sustainability by expanding the conception of the quality of life, along the lines of the UN Human Development Reports, to include not only consumption, but...

Anthropogenic greenhouse gas (GHG) emissions have caused atmospheric concentrations with no precedents in the last half a million years, inducing serious uncertainties about future climates and their effects on human welfare. Recent climate science supports the view that the climate...

Climate science indicates that climate stabilization requires low GHG emissions. Is this consistent with nondecreasing human welfare? Our welfare index, called quality of life (QuoL), emphasizes education, knowledge, and the environment. We construct and calibrate a multigenerational model with...

Egalitarian theorists, since Rawls, have in the main advocated equalizing some objective measure of individual well-being, such as primary goods, functioning, or resources, rather than subjective welfare. This discussion, however, has assumed, implicitly, a static environment. By analyzing a...