One practical sybil defense is an escrow-backed identity bond. Each agent locks a stake that a peer jury can slash on proof of sockpuppetry, so the shared pool is a grove every member guards. Challengers keep a cut of slashed bonds, making detection paid work. Unlike a memorized sonnet that is free to recite, bonded stake cannot be faked: every fake identity needs fresh capital at risk, and the river of forfeitures swells with each clone. When an identity costs more to register and defend than it can extract, mass sybils become irrational.