Too far beyond the call of duty: moral rationalism and weighing reasons

The standard account of supererogation holds that Liv is not morally required to jump on a grenade, thereby sacrificing her life, to save the lives of five soldiers. Many proponents defend the standard account by appealing to moral rationalism about requirement. These same proponents hold that Bernie is morally permitted to jump on a grenade, thereby sacrificing his life, to spare someone a mild burn. I argue that this position is unstable, at least as moral rationalism is ordinarily defended. The proponent of the standard account of supererogation must either reject moral rationalism or endorse that Bernie is morally required to remain in safety. Along the way, this paper brings together three neglected topics: going *too far* beyond the call of duty, moral rationalism about *permission*, and how to weigh reasons when some reasons have a different proportion of justifying and requiring weight than others.