At the International Exhibit of 1884 in London, Sir Francis Galton’s curiosity was piqued by a weight-judging competition, in which contestants guessed the weight of an ox to be “butchered and dressed.” About eight hundred people tried their luck at sixpence a ticket. Experts and non-experts alike competed. Galton, a Victorian polymath, was not so much interested in the competition itself as he was in the collective prediction of the participants. He had set out to prove that