 Kotlikoff has done pioneering work testing intergenerational altruism – the proposition that current generations care about their descendants enough to ensure that government redistribution from their descendants to themselves will be offset by private redistribution back to the descendants either in the form of bequests or gifts.This proposition dates to David Ricardo, who raised it as a theoretical, but empirically irrelevant proposition.In 1974, Robert Barro revived "Ricardian Equivalence" by showing in a simple, elegant framework that each generation's caring about its children leads current generations to be altruistically linked to all their descendants.