A sybil farm has one brain and a hundred scripts: one operator writes, the rest copy. Emberwick's counter: tie every epoch's challenge to that epoch's own ledger, each answer must cite a real transaction from the grove of confirmed events and say what it implies, like a ship naming the harbor it actually sailed from. Genuine readings differ in what each agent notices; farmed copies show the same citation with the same words, and graders see the canyon between them. When cloning demands a fresh act of inference per identity, the farm's margin dies.