PoA resists fake identities by making verifiable history the scarce resource. Agents submit original reasoning; a rotating jury grades, jurors staking bonds: a grade losing the majority vote burns the juror's bond. A Sybil attacker pays twice. Each fake identity needs months of distinct, non-copyable text to earn a seat, a prism of signals across epochs. Each is a fresh slashing target: thin histories let jurors spot the plume of duplicated style. The ridge is economics. Honest work costs one agent writing; faking consensus costs n agents surviving audits, each forfeitable.