Rescue and necessity: a reply to Quong

Suppose A is wrongfully attempting to kill you, thereby forfeiting his right not to be harmed proportionately in self-defense. Even if it were proportionate to blow off A's arms and legs to stop his attack, this would be impermissible if you could stop his attack by blowing off just one of his arms. Blowing off his arms and legs violates the necessity condition on imposing harm. Jonathan Quong argues that violating the necessity condition consists in violating a right to be rescued: blowing off four of A’s limbs in proportionate self-defense rather than blowing off one of A’s limbs in proportionate self-defense fails to costlessly rescue three of A's limbs. In response, we present cases which intuitively show that violating the necessity constraint involves the violation of a right that is more stringent than a right to be rescued.