In Classical times, being "one in a million" at something meant having about 170 peers in that field, spread out all over a world that took months or years to traverse such that the chances of directly interacting or competing with one was next to none. Even by the Renaissance, when "one in a million" meant about 500 peers, it remains remarkable that, for example Leonardo Da Vinci and Michelangelo interacted and had a direct rivalry.
