ABSTRACT
James Griffin distinguishes “discontinuity” and “rough equality” in discussing “incommensurability.” Derek Parfit invokes both in his discussion of how to avoid the Repugnant Conclusion. I present an account of value relations based on a reading of Griffin’s and Parfit’s views. This allows for parity understood as a distinct relation of “rough equality.” An account that extends Griffin’s remarks about “discontinuity” and the Repugnant Conclusion by allowing for vagueness is contrasted with Derek Parfit’s later account, which invokes “imprecise equality.” Invoking both “discontinuity” and “imprecise equality,” as Parfit does, appears to double count “incommensurability” and runs into difficulties. Parfit’s view may be rescued if the account of value relations does not interpret parity in terms of “rough equality.” Certain objections can be leveled at both Parfit’s account and the account which develops on Griffin’s remarks, yet the latter arguably has the advantage that it invokes only one form of “incommensurability.”
