Population ethics is widely considered to be exceptionally important and exceptionally difficult. One key source of difficulty is the conflict between certain moral intuitions and analytical results identifying requirements for rational (in the sense of complete and transitive) social choice...

Utilitarianism is the most prominent family of social welfare functions. We present three new axiomatic characterizations of utilitarian (that is, additively separable) social welfare functions in a setting where there is risk over both population size and the welfares of individuals. First, we...