A very rare eternal life (長生) position appeared recently in the 2013 Korean Baduk League.
When it appeared on the board, Kang Hun 9p, who was the referee for the game, came and judged it to be a draw.
We call this situation eternal life (長生 – chosei in Japanese), because it creates an endless cycle of moves in which neither player can win unless they’re willing to give up on the local situation.
It’s similar to the sort of repeating cycle that can occur when there are several kos on the board, but more complicated because it consists of four moves. This kind of repetition voids the game and leads to a draw under the Japanese rules.
The diagram above shows the position near the end of Choi and Ahn’s game. Black just played at D and it’s white’s turn to play.
Right now black could live by playing at A, so white plays a throw-in there to prevent it. After white A, if black captures with C, he’ll die after white responds with B. So black’s best option is to play B himself.
After black B, white’s in atari, so he captures two stones with C, then black’s in atari and he captures two stones with D. Now we’re back where we started.
You can have a look at the game record to see the position in more detail, and you can also try a very similar Go problem below.
Ahn Seongjun vs Choi Cheolhan
A first in Korean professional Baduk
Eternal life has never been seen before in official games in Korea, so this will be recorded as the first eternal life game in the history of Korean Baduk.
In an interview after the game, Choi said, “I feel happy and honored to create eternal life in my game but, on the other hand, it’s a pity for my team that I wasn’t able to win the game as captain.”
Other instances of eternal life
According to Baduk (Dec 1993), a Go magazine in Korea, the first official game in which eternal life appeared was played in Japan. The game was played in the 49th Honinbo league, between Rin Kaiho 9p and Komatsu Hideki 8p, on September 02, 1993.
The game was nearly finished, and it was a very close ‘half point’ game. Neither player could afford give way to avoid the situation, and the game ended as a draw.
However, if this had happened in another tournament, such as the Ing Cup (which uses Ing Rules), it would have been regarded as a special type of ko, so the players would have had to find a ‘ko threat’ before repeating the cycle.
Rin Kaiho vs Komatsu Hideki
Go Seigen once said, “eternal life only happens in one in a million games, so if it ever happens in one of your games, you should cook rice together with red bean and celebrate.” This is a quote from his memoirs.
Uchida Shuhei vs O Meien
Other than the two games mentioned above, there have never been any other reports of eternal life in official games. So (if that’s true) Choi and Ahn’s game is the third official instance of eternal life in professional Go, and the first in Korean Baduk history.
A Go problem featuring eternal life
Here’s a classic Go problem that involves eternal life, to help you understand this kind of situation better.
Rarer than a triple ko
Games featuring a triple ko, or the quadruple ko, are extremely rare too. However, they still appear more often than eternal life does.
Last year there was a quadruple ko in a game between Gu Li 9p and Lee Sedol 9p, at the 17th Samsung Cup. I posted a commentary of the quadruple ko game at the time.
Congratulations to Choi and Ahn
As Go Seigen said, this is an event that should be celebrated and congratulated in the Go world.
Congratulations to Choi Cheolhan and Ahn Seongjun, who made this happen in real in life!
Their game will long be remembered as a very special scene in the long history of Go.