In 2007, New Scientist announced that the best strategy in a game of rock paper scissors is to choose scissors.

Research has shown that rock is the most popular of the three moves. If your opponent expects you to choose it, he’ll choose paper in order to beat it — in which case scissors will win.

In 2005 a Japanese art collector asked Christie’s and Sotheby’s to play a match, saying the winner could sell his impressionist paintings. The 11-year-old daughter of a Christie’s director recommended scissors, saying, “Everybody expects you to choose rock.”

Sure enough, Sotheby’s chose paper, and Christie’s won the £10 million deal.