MICH: If you’re an egalitarian, how come you’re not a vegan?

Martin van der Linden (Utah State University)

We study fairness in economies where humans consume one private good and one public good, the latter representing the welfare of other species. We show that it is impossible for a social planner to be egalitarian with respect to humans and be speciesist in the sense of always respecting unanimous preferences among humans. One way out is to limit respect for unanimity among humans to situations where the welfare of other species increases. We characterize classes of maximin social ordering functions that satisfy egalitarian axioms and this natural restriction of unanimity. Characterizations based on these two principles reveal a link between egalitarianism among humans and concerns for other species: a form of dictatorial power must be given to humans with the strongest preferences for other-species’ welfare.