A Theory of Intergenerational Altruism
公理化地发展了纯直接利他主义理论，定义了利他偏好新类别，并刻画了准双曲线贴现模型，为分析利他偏好下的福利问题提供了框架。
Modeling intergenerational altruism is crucial to evaluate the long-term consequences of current decisions, and requires a set of principles guiding such altruism. We axiomatically develop a theory of pure, direct altruism: Altruism is pure if it concerns the total utility (rather than the mere consumption utility) of future generations, and direct if it directly incorporates the utility of all future generations. Our axioms deliver a new class of altruistic, forward-looking preferences, whose weight put on the consumption of a future generation generally depends on the consumption of other generations. The only preferences lacking this dependence correspond to the quasi-hyperbolic discounting model, which our theory characterizes. Our approach provides a framework to analyze welfare in the presence of altruistic preferences and addresses technical challenges stemming from the interdependent nature of such preferences.