To clarify, this is if we’re increasing their welfare by the same amount, right? Prioritarianism and egalitarianism wouldn’t imply that it’s better for the mouse to be moved to 10 than for the human to be moved to 100.
Right. The claim is that the prioritarian and the egalitarian would prefer to move the mouse from 9⁄10 to 10⁄10 before moving the human from 10⁄100 to 11⁄100. Kagan argues this is the wrong result, but because he doesn’t want to throw out distributive principles altogether, he thinks the best move is to appeal to differences in moral status between the mouse and the human.
Right. The claim is that the prioritarian and the egalitarian would prefer to move the mouse from 9⁄10 to 10⁄10 before moving the human from 10⁄100 to 11⁄100. Kagan argues this is the wrong result, but because he doesn’t want to throw out distributive principles altogether, he thinks the best move is to appeal to differences in moral status between the mouse and the human.