Sansukumi-ken

Sansukumi-ken (三すくみ拳) is a category of East Asian hand games played by using three hand gestures. Ken games went into a period of decline in Japan after World War II. One of the few surviving sansukumi-ken games is jan-ken, which was brought to the West in the 20th century as rock-paper-scissors.

East Asia has a long history of hand games, which are known as ken games in Japan. Ken was brought to Japan in the 17th century as a Chinese drinking game. Aside from drinking, ken games were also popular in brothels as a form of foreplay. The earliest Japanese ken games are called Nagasaki-ken or Kiyo-ken because of the belief that ken games were first popularized by the Chinese community in Nagasaki.Kensarae sumai zue, a 1809 handbook for ken games, contains a speech read by ken tournament referees that summarizes the history of ken. The speech chronicles ken as a game played by the emperors of ancient China during drinking parties. It recounts a traditional story about the origin of ken in Japan. The story is set in Nagasaki's Maruyama red light district approximately 150 years prior to the publication of the handbook. The Chinese hosted a party in Maruyama and held Japan's first ken tournament after feasting and dancing. The party guests competed until five of the best ken players were selected and awarded expensive prizes. The importance of the party is never made clear in the speech, but the story is useful for understanding the cultural background of ken games.

Ken games played with three hand gestures became popular in the 18th century. They were named sansukumi-ken, which translates into "ken of the three who are afraid of one another." The oldest sansukumi-ken game is mushi-ken (虫拳), a game originally from China. In mushi-ken, the "frog" represented by the thumb wins against the "slug" represented by the little finger, which, in turn defeats the "snake" represented by the index finger, which wins against the "frog". Although this game was imported from China, the Japanese version differs in the animals represented. In adopting the game, the original Chinese characters for the poisonous centipede (蜈蜙) were apparently confused with the characters for the "slug" (蛞蝓). The centipede was chosen because of the Chinese belief that the centipede was capable of killing a snake by climbing and entering its head.

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