I outline a dilemma for Derek Parfit’s project to vindicate moral realism. In On What Matters, Parfit argues that the best versions of three of the main moral traditions agree on a set of moral principles, which should make us more confident about the prospects of truth in ethics. I show that the result of this Convergence Argument can be interpreted in two ways. Either there remain three separate and deontically equivalent theories or there remains just one theory, the Triple Theory. Both interpretations fail to deliver what Parfit is looking for. The first interpretation leads to a situation of underdetermination of theory choice that gives rise to a skeptical challenge. The second interpretation jettisons Parfit’s Conciliatory Project, that is, the reconciliation of the three moral traditions. The dilemma, I contend, is the result of Parfit failing to resolve two antithetical lines of thought. His search for the Trinity of moral theorizing must thus fail.

我概述了德里克·帕菲特 (Derek Parfit) 为维护道德现实主义而进行的项目的困境。在重要的事情上帕菲特认为，三种主要道德传统的最佳版本都同意一套道德原则，这应该使我们对伦理真理的前景更有信心。我展示了这个收敛论证的结果可以用两种方式来解释。要么保留三个独立的、道义上等效的理论，要么只保留一个理论，即三重理论。两种解释都未能提供帕菲特所寻求的东西。第一种解释导致了理论选择的不确定性，从而引起了怀疑的挑战。第二种解释抛弃了帕菲特的和解计划，即三种道德传统的和解。我认为，这种困境是帕菲特未能解决两个对立的思路的结果。