Six Degrees of Kevin Bacon is a trivia game based on the concept of the small world phenomenon and rests on the assumption that any individual can be linked through his or her film roles to actor Kevin Bacon within six steps. Now there’s the Shusaku number, which represents the “distance” between a go player and Honinbo Shusaku, measured in go opponents.
Kuwahara Shusaku (1829-1862) was the strongest player of Japan’s “Edo” period, a “golden age of go” where four “houses” devoted themselves to winning the honor of playing in the “Castle Games” for the Emperor. The author of the most famous move in go history – the so-called “ear-reddening move” – Shusaku once famously responded, when asked the result of a game, “I had black.” (The komi system was still more than fifty years in future.) He won nineteen consecutive games over a thirteen-year period, an unparalleled achievement, before dying of cholera at age 33. To equal this achievement today, a player would have to win every game on white by at least eight points. The ideas Shusaku left behind, especially the so-called “Shusaku opening,” formed the foundation of go theory for the next 
hundred years.
How closely are you connected to Shusaku? Borrowing from the world of mathematics, where authors proudly calculate their “Erdos number”, some go players enjoy figuring out their “Shusaku number,” a series of games leading back to the historic figure. For instance, The E-Journal’s erstwhile translator Bob McGuigan’s “Shusaku number” is four, a very respectable achievement for an amateur player. McGuigan once played a game with Sumiko Shiratori 5P, who in turn once played Fumiko Kita 6P, an important figure in the Hoensha, forerunner of today’s Nihon Kiin. Ms. Kita in turn once played Hoensha founder Honinbo Shuho, Shusaku’s unlucky opponent in four “Castle Games.” That’s a three-player link, so Bob is a four. (Shusaku’s “Shusaku number” is of course zero.) If you have ever played Bob, you are a five. Click here to learn how to trace your “go lineage” to the great master. When you’ve got that all figured out you can take it to the next level, and try to figure out your “Winning Shusaku Number,” where you have to trace a series of victories all the way back to someone who beat Shusaku. Handicap wins on black don’t count, so good luck with that . . .
– Roy Laird
