Chess is the touchstone of the intellect,” said Goethe, German poet and 18th-century polymath. Alfonso X, King of Leon and Castile 1222-1284, known as The Wise, would have agreed. The intellectual allure of a game with no luck element and an incompletely known algorithm is recorded in Alfonso’s manuscript Book of Games (1283): this picture from it shows two Arabs intent on the “sport of kings”. Chess, first recorded in India before 600AD, came to Europe via Persia and the Moorish invasins. As early as the 9th Century, Arab authors compiled chess problems, very similar to those studied today. Written as stories rather than geometry puzzles, the Mansubat offer elegant, if long-winded, solutions. Today’s chess is faster (the savagely powerful queen, two-square pawn opening and castling all postdate Alfonso) but no less addictive, as school tournaments demonstrate. For more about the history of chess and examples of Arab problems, start at www.chessvariants.com