Kanō Jigorō (嘉納 治五郎, 10 December 1860 – 4 May 1938) was a Japanese judoka, educator, politician, and the founder of judo. Judo was one of the first Japanese martial arts to gain widespread international recognition, and the first to become an official Olympic sport. Pedagogical innovations attributed to Kanō include the use of black and white belts, and the introduction of dan ranking to show the relative ranking among members of a martial art style. Well-known mottoes attributed to Kanō include "maximum efficiency minimal effort" (精力善用, seiryoku zen'yō) and "mutual welfare and benefit" (自他共栄, jita kyōei).