It seems to me that the basis for equality is not first-order utility, but rather symmetry amongst utility changes.
If the lives of Person A and Person B are equal in value, then the world in which A kills B and loots the corpse is no better or worse than the world in which B kills A and loots the corpse.
A timeless argument: “If I decide to kill the other guy, then — since our situations are symmetric — he will decide to kill me, too; and neither of us will get to loot the corpse.”
A social argument: “Some third party C doesn’t care if I kill him or he kills me; but certainly prefers that neither of us kill the other and then turn on him with the combined resources of both. So C is motivated to deter either of us from killing and looting the other.”
It seems to me that the basis for equality is not first-order utility, but rather symmetry amongst utility changes.
If the lives of Person A and Person B are equal in value, then the world in which A kills B and loots the corpse is no better or worse than the world in which B kills A and loots the corpse.
A timeless argument: “If I decide to kill the other guy, then — since our situations are symmetric — he will decide to kill me, too; and neither of us will get to loot the corpse.”
A social argument: “Some third party C doesn’t care if I kill him or he kills me; but certainly prefers that neither of us kill the other and then turn on him with the combined resources of both. So C is motivated to deter either of us from killing and looting the other.”