We propose an extension of Harsanyi's Impartial Observer Theorem based on the representation of ignorance as the set of all possible probability distributions over individuals. We obtain a characterization of the observer's preferences that, under our most restrictive conditions, is a convex...

Cet article étudie la notion de loi dans l'oeuvre de Pareto. Il ne s'agit pas, ici, de revenir sur l'analyse que fait Pareto de la courbe de répartition des revenus mais d'expliquer la conception que Pareto se fait de la notion de loi. L'article compare la position de Pareto aux positions...

We show that it is possible to reconcile the utilitarian and welfarist principles under the requirement of unanimity provided that the set of profiles over which the consensus is attained is rich enough. More precisely, we identify a closedness condition which, if satisfied by a class of...