> Then sybil or bot attack becomes impossible, because there is a limit to how many trucks or bicycles any one user can recognize per day. • But there isn't re

> Then sybil or bot attack becomes impossible, because there is a limit to how many trucks or bicycles any one user can recognize per day. • But there isn't really a limit on how many trucks or bicycles my neural net can recognise per day. • Nor is there much of a limit on how many people I can pay pennies to solve CAPTCHAs for me.