Abstract

This comment discusses the book's positive account of the trolley problem, given in the Principle of Permissible Harm. This principle says an act that causes both a greater good and a lesser evil is impermissible if the evil results from a means to the good but can be permissible if the evil results from the good itself or from its noncausal flip side. This comment argues that this principle has counterintuitive implications—for example, that bombing an arms factory that kills nearby civilians is impermissible if the civilians are killed by flying pieces of bomb but permissible if they are killed by flying pieces of factory. It then argues that the principle lacks a persuasive philosophical rationale because it draws an arbitrary line in a sequence of means to an end and trades on an ambiguity in its understanding of “the greater good.”