Maximal Social Welfare Relations on Infinite Populations Satisfying Permutation Invariance

We study social welfare relations (SWRs) on an infinite population. Our main result is a new characterization of a utilitarian SWR as the \emph{largest} SWR (in terms of subset when the weak relation is viewed as a set of pairs) which satisfies Strong Pareto, Permutation Invariance (elsewhere called Relative Anonymity'' and Isomorphism Invariance’‘), and a further ``Quasi-Independence’’ axiom.