Monopoly

Which came first to the designers of chess: the rules or the metaphor? It feels impossible to prise the system from the story: a military battle between two monarchs, each with perfectly symmetrical assets and equally balanced capabilities. Yet there have been dozens of ‘reskins’ of chess, swapping the kings and their minions for characters from, say, Lord of the Rings, or The Simpsons, or even, bewilderingly, M&M chocolates. Play is the primary way in which every human first tests and explores the world  Sometimes the new metaphor imbues the game with a socio-political frisson. A recent example pitches rockers – white men in leathers holding screaming guitars – against jazz musicians – black men in white suits nursing saxophones.

If both players in a game of draughts stick to their optimal moves, the game will always end in a draw. You or I might have guessed that anecdotally. But being a mathematician, Marcus du Sautoy knows it for sure. The calculations that proved it took 200 desktop computers 18 years to perform. The Prussian High Command used a game called Kriegsspiel to test the abilities of aspiring officers When such a simple game produces such numerical complexity, imagine the fun a mathematician can have with something like Go, the Chinese institution whose number of possible games contains an estimated 300 digits. (The number of atoms in the observable universe only contains 80.