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Eternal Life
Path: LifeAndDeath   · Prev: DoorGroup   · Next: ApproachingALifeAndDeathProblemTheRightWay
Path: SecondCourseOnKo   · Prev: BentFourInTheCornerIsDead   · Next: RepeatingPositions

    Keywords: Ko, Rules

Chinese: 长生

Eternal life is yet another situation where a void game (no result: neither player wins, but neither player loses) can occur, under rulesets which permit such a thing. Several special rules, such as superko and the Ing Ko Rule, forbid the recurring sequence to occur.

However, eternal life is so rare in games that if one occurs, a Chinese Go text says that:

  You should buy fish, vegetables, meat and wine
  And have a good party to celebrate yourself

Of course, it's an exaggeration...

[Diagram]
Diag.: Eternal life

This is the situation to begin with.


[Diagram]
Diag.: Eternal life

Black 1 begins by sacrificing two stones (to prevent the formation of bulky five)...


[Diagram]
Diag.: Eternal life

Black 3 takes back two white stones...


[Diagram]
Diag.: Eternal life

White makes a throw in at 4 to destroy the eye, and the cycle repeats itself when Black 5 sacrifices two stones again.



--unkx80


Bill:

White has the option of making seki:

[Diagram]
Diag.: Seki


But suppose White needs to kill Black in order to win, and Black would never let go of his group, then eternal life occurs.


Bill: Strictly speaking the position after White 1 in the Seki diagram is not seki, but a hyperactive position. However, when it is correct to make the play, it will almost always become seki.


Chosei

Does anybody know what a Chosei is and what the term means? It somehow seems to be related to Ko.

--Confused

It is the type of position called long life in this reference:

[ext] http://www-2.cs.cmu.edu/~wjh/go/rules/Japanese.html .

The point is that it is a cyclic position with two stones captured at a time.

There was some excitement about this thirty years ago when a variation of the kado joseki played in a title game Sakata-Yamabe could have led to chosei.

Charles Matthews

So, chosei is the same thing as eternal life I wrote some time ago? --unkx80


See Kanazawa Attempts 85.



Path: LifeAndDeath   · Prev: DoorGroup   · Next: ApproachingALifeAndDeathProblemTheRightWay
Path: SecondCourseOnKo   · Prev: BentFourInTheCornerIsDead   · Next: RepeatingPositions

This is a copy of the living page "Eternal Life" at Sensei's Library.
(OC) 2003 the Authors, published under the OpenContent License V1.0.