Although Euwe was World Chess Champion for a "mere" two years, he certainly left his mark in the web pages of chess history. He alone managed to defeat Alekhine. But, not only in his defeat of Alekhine did Euwe become a chess great, but also in his extensive contributions to middle game theory. Euwe preferred playing matches to playing in tournaments because of the psychological aspects of matches. He enjoyed preparing special variations to take advantage of his opponents' fears. Euwe had other interests besides chess. He was a mathematician. After his brief dance with the World Championship, Euwe went on to become a Professor of Cybernetics. However, Euwe never lost his love of chess. He took on the presidency of FIDE from 1970 through 1978.