The ancient game of checkers is dead, following a long illness. Checkers, also known as draughts, has been killed by a mathematical proof that shows the game always results in a draw if neither player makes a mistake.
A steady stream of games has succumbed to computer attack, including , which was “solved” more than 10 years ago. But it took 18 years for Jonathan Schaeffer, a computer scientist and games specialist at the University of Alberta in Canada, to solve checkers (Science, ).
Schaeffer has used the proof to update the checkers-playing program Chinook, which in the 1990s failed to beat the then world champion Marion Tinsley, who is still regarded as the greatest player ever. The revamped Chinook, which is , can no longer be beaten, Schaeffer says. “The best result you can get is a draw.”
Advertisement
In checkers, players capture their opponents’ pieces towards the end of the game, resulting in many pieces being quickly removed from play. Schaeffer used a computer to work out all of the 39 trillion possible endgames that involve fewer than 10 pieces. He then used this to show that all 19 possible opening moves lead to a draw in the endgame, provided both players play perfectly.
The proof has taken the fun out of the game for David Levy, president of the International Computer Games Association in London, who doesn’t plan to play Chinook. “There would be a certain inevitability about the result,” he says.
