Has every possible chess game been played?
In the past 500 years of modern chess, have we even come close to playing all iterations of the game?
Asked by: Lucy Metcalfe, Liverpool
The modern game of chess is around 500 years old, so to put a rough upper limit on the total number of games played so far, let's assume around one per cent of people who have lived since then have played a different game of chess every day for 50 years. That means that around 10 million million games of chess have been played. That sounds a lot but each move in chess opens up around 38 legal new moves, and a typical chess match consists of around 40 or so moves per player. So the total number of moves possible is around 38 to the power 80, which works out at a staggering 10 to the power 126 - far larger than the number of particles in the visible Universe. So no, we're not even close to exhausting the possibilities of chess.
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Robert is a science writer and visiting professor of science at Aston University.
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