The point is, to a utilitarian, it’s a finger, because part of the setup is that the “mugger” won’t use their finger for bad things in the future.
Maybe not part of this specific dialogue, where the mugger repeatedly asks for rhetorical reasons. But in a case where there is only a single instance of a mugging, the assumption is that the mugger will only mug once.
Maybe not part of this specific dialogue, where the mugger repeatedly asks for rhetorical reasons. But in a case where there is only a single instance of a mugging, the assumption is that the mugger will only mug once.