About Ko in a Semeai Between
Two One-Eyed Groups (2012)
(Referenced by This chapter explains the theoretical foundations of a special type of semeai, which arises in Joachim Meinhardt's idea ( The presentation follows the course of our growing insights into this particular formation. For a long period of time we were unsure about the best time to start the ko-fight, especially whether White should choose an "early" ko (i.e. a few moves after creating the ko-formation) or a "late" one (i.e. after Black connected the hanezeki's tail). Please understand this chapter to be supplementary only now; probably it might be still useful for readers with a more mathematical approach. It was written before our intense work on "Putting the Cart Before the Horse" ( | A Special Type of Semeai | ![]() |
The Simple Version - No Hanezeki | ![]() |
Larger Eyes | ![]() |
A Second Ko-Shape for White | ![]() |
[ Second Ko-Shape for White & Larger Eye for Black ] | ![]() |
A Second, and Shared, Ko-Shape | ![]() |
[ Shared Ko-Shape & Outside Ko for White ] | ![]() |
The Effect of the Hanezeki | ![]() |
Effective liberties | ![]() |
Number of Ko-threats | ![]() |
White's False Eyes | ![]() |
[ Larger Eye for Black ] | ![]() |
[ Shared Ko-Shape in the Centre ] | ![]() |
The Semeai with Black's Group in the Lower Right | ![]() |
[ Black's Effective Liberties ] | ![]() |
[ Impact on the Main Ko-Semeai ] | ![]() |
[ The Construction Process Makes the Difference ] | ![]() |
White's Group on the Left Edge | ![]() |
Conclusion | ![]() |