We study fairness in economies where humans consume one private good and one public good representing the welfare of other species. We show that a social evaluator cannot be egalitarian with respect to humans while always respecting humans' unanimous preferences. One solution is to respect...

Social justice considerations are incorporated into welfare economics via properties of the social welfare function and measures of individual utility. The ethical issues underlying various approaches are illustrated through intriguing paradoxes that have emerged in the literature. Such puzzles...