Emanuel Lasker (December 24, 1868 – January 11, 1941) was a German chess player, mathematician, and philosopher who was World Chess Champion for 27 years. In his prime Lasker was one of the most dominant champions, and he is still generally regarded as one of the strongest players ever. It is often said that that Lasker used a "psychological" approach to the game, and even that he sometimes deliberately played inferior moves to confuse opponents. However recent analysis indicates that he was ahead of his time and used a more flexible approach than his contemporaries, which mystified them. Although Lasker also published chess magazines and two chess books, later players and commentators found it difficult to draw lessons from his methods. While it is often said that Lasker spent little time studying the openings, he actually knew the openings well but disagreed with many contemporary analyses. He demanded high fees for playing matches and tournaments, which aroused criticism at the time but contributed to the development of chess as a professional career. The conditions which Lasker demanded for world championship matches in that last 10 years of his reign were controversial, and prompted attempts, particularly by his successor José Raúl Capablanca, to define agreed rules for championship matches. Lasker was also a talented mathematician, and his Ph.D thesis is regarded as one of the foundations of modern algebra. His attempt to produce a general theory of competitive activities had some influence on the early development of game theory, and his books about games in general presented a problem which is still regarded as notable in the mathematical analysis of card games. However his philosophical works and a drama which he co-wrote now receive little attention. (via Wikipedia)