, both in a static and in an intertemporal framework. Section 5 deals with the special case of utilitarianism. We review some … welfarism theorem to a variable-population framework and provide a characterization of critical-level generalized utilitarianism …

Fuzzy set theory has been explicitly introduced to deal with vagueness and ambiguity. One can also use probability … theory or techniques borrowed from philosophical logic. In this chapter, we consider fuzzy preferences and we survey the … literature on aggregation of fuzzy preferences. We restrict ourselves to “pure aggregation” theory and, accordingly, do not cover …