Can Parfit’s Appeal to Incommensurabilities Block the Continuum Argument for the Repugnant Conclusion?
Blocking the Continuum Argument for the Repugnant Conclusion by an appeal to incommensurabilities in value, as suggested in Parfit (2016), is an attractive option. But incommensurabilities (‘imprecise equalities’ in Parfit’s terminology) that need to be posited to achieve this result have to be very thoroughgoing – ‘persistent’ in the sense to be explained. While this persistency is highly atypical, it can be explained if incommensurability is interpreted on the lines of the fitting-attitudes analysis of value, as permissibility of divergent attitudes towards the items that are being compared. More precisely, it can be interpreted as parity – as the permissibility of opposing preferences with respect to the compared items. This account makes room for the persistency phenomena. Nevertheless, some of Parfit’s substantive value assumptions must be given up, to avoid implausible implications. In particular, his Simple View regarding the marginal value of added lives cannot be retained.