Economie du débat intergénérationnel. Points de vue normatif, comptable, politique

This paper analyses three debates related to intergenerational economics. The first one is normative : it deals with the responsability of individuals towards their successors : is individual altruism enough, or must the State represent the absent and the young children ? In the latter case, public "solidarities" rest on indirect reciprocities (between three generations) and go both ways : the problem of the "just inheritance" (education, bequests, environment…) to the next generations and that of the "just claim" (public debt, pay-as-you-go retirement system) on these generations are closely linked. The second debate is positive : it concerns the sustainability of tranfer policies, as measured by generational accounting : the method rests on a virtual scenario which should, ideally, eliminate purely conjunctural measures. In any case, as the accounts focus mainly on the problem of the just claim, while ignoring the non monetary future services of public expenditures problem of the just claim, while ignoring the non monetary future services of public expanditures (investments), Kotlikoff's alarmist conclusions about generational equity do no appear warranted. The third debate concerns the optimal level and the priorities (towards the young or the old) of age redistribution. The Beckerian model of intergenerational cooperation has the original feature to combine family altruism with a high level of public, downward and especially upward, redistribution : such a suprising stand can be explained by Becker's paternalistic (neo-Marshallian) view of the Welfare State). The contradictions of this model, however, tell in favour of extensions borrowed from anthropology : altruism could be advantageously replaced by indirect reciprocities ; and the fundamental "ambivalence" of any gift or transfer should lead to new models combining elements of intergenerational cooperation and fighting.