In a disagreement, two parties affirm and deny the same thing; because the parties contradict each other, they cannot both be right; because they cannot both be right, there is something to be resolved between them by figuring out which of them is mistaken; a disagreement remains unresolved so long as both parties continue to think the other is mistaken; it is irresolvable when there is no method by which to resolve it. While moral truths hold objectively, they do not hold universally, only locally. It’s possible for two people to live in different moral worlds, in which different moral truths hold.