The repugnant conclusion and internal consistency of choice - Susumu Cato

The repugnant conclusion and internal consistency of choice - Susumu Cato
Photo by Brandi Redd on Unsplash

Speaker: Susumu Cato

The mere addition paradox pioneered by Derek Parfit is revisited. The paradox revolves around two conditions: "mere addition," which posits that adding individuals with positive utility should make a population at least as good as the original, and "non-anti-egalitarianism," suggesting that any distribution is worse than an egalitarian one with a higher average utility if the population remains unchanged. Paradoxically, these conditions lead to the repugnant conclusion, stating that for any larger population P with very high utility levels, there is a much larger population,  including only individuals barely worth living, that is better than P. I will develop a novel approach to this problem called "non-binary population ethics". Instead of using a betterness relation, it employs a choice function to assign permissible populations to menus of options. Notably, my results show how the mere addition paradox relies on internal consistency axioms. These results underscore the persistence of the repugnant conclusion, suggesting that the paradox's root lies beyond issues of transitivity or coherency in better-than relations. Also, I offer a new resolution of the paradox.

Please note that these seminars are open to the public and in person only.

Date & time

Thu 19 Oct 2023, 2:00pm to 3:30pm


Auditorium, Level 1, RSSS building, 146 Ellery Crescent, Acton, ACT 2601


Susumu Cato


Sean Denahue


Updated:  12 October 2023/Responsible Officer:  Head of School/Page Contact:  CASS Marketing & Communications