Octopuses (Probably) Don't Have Nine Minds

This is the sixth post in the Moral Weight Project Sequence, which provides an overview of the research Rethink Priorities conducted between May 2021 and October 2022 on making resource allocation decisions across species. In this post, Joe Gottlieb summarizes his full report on phenomenal unity and cause prioritization. He concludes that there is not enough empirical evidence to assume that certain species “house” multiple welfare subjects per individual.