Rules of Go
The forfeiture of the game can be understood when reviewing the rules of go. Let's have a look at them.
1. Black plays first.
2. Stones are placed on the intersection points.
3. Stones do not move unless captured.
4. Stones must be removed from the board when they lose all their liberties.
5. The player with the most territory at the end of the game wins.
6. A board situation cannot be repeated.
How does this work in practice?
Diagram 1: Using a 9x9-line beginner's board, we can see that black 1 has four liberties, A through D. After moves 2 through 6, black 3 is in a situation called atari because it has only one liberty. However, when Black plays at 7, white 4 is in atari. White captures black 3 by playing at 8. But Black puts white 4 in atari again when he plays at 9. White then cuts at 10. What is going on?
Diagram 2: Black can capture the marked white stone by playing at 11. Now, a problem arises. White wants to capture black 11, but that is not allowed because the rules prohibit a board position from being repeated. The position after white 10 is called a ko, and White must play elsewhere first before capturing black 11. If Black answers white 12, then White can play at 14 (not shown) to retake the ko. Black must now play elsewhere (15) and White can end the ko by connecting where the marked white stone had been captured. Alternatively, he could answer black 15 by playing at 16. Black can now take the ko with 17 (not shown). White plays elsewhere with 18, hoping that Black will answer with 19. White can then retake the ko with 20 (not shown), leaving Black to capture white 18 with 21, but white 22 also captures a stone.
The new Kisei
Last week, we looked at the start of the decisive second game in which Naoki Hane defeated Keigo Yamashita to become the new Kisei. Let's have a look at how this game developed.
Diagram 3: With the marked stone, White launches a strong attack. Although black 1 seems to be a natural response, white 2 hits the vital spot. Black comes back later with 11 to make an eye, while White takes a superior center position with 12. White's capture of black 17 with 16 through 22 and a follow-up attack with 32, 38 and 40 are decisive. Black has weak groups, while White is making territory everywhere.
Solution to last week's problems
Solution 1A: Black 1 is sometimes correct. If White cuts with 2 and 4, Black gets thickness in the center to mount an attack on the marked white stones. Black may hem in White by playing around A.
Solution 1B: In this case, Black overplays with 1. To help the marked white stones, White has a splendid combination with 2 and 4, followed by an unlikely move at 6. Black is forced to connect with 7, but white 8 puts eight black stones in atari. Black needs to connect at the spot where white 4 was captured. This is a disaster for Black as he has a block of stones without any eyes, while White has the initiative.
Solution 2: In response to White's move (marked stone), Black could have played 1 through 7, then defend with 9. In this way, he would create an eye at A and at B at all times. But this passive way of playing, although safe, is not Yamashita's style. In the actual game, this black group and the one on the left will lose their eyes and come under strong attack.
New Problems
Problem 1: Black plays first and kills the white stones.
Problem 2: Black to play and kill the white stones.
Want to find out more? Come to Ben's Cafe in Takadanobaba, Tokyo (03-3202-2445) where the English speaking go community congregates every Sunday. You can enjoy free lessons, 11 a.m.-1 p.m. Ben's Cafe can be accessed at www.benscafe.com.
Van Zeijst is a four-time European go champion and European representative at the Fujitsu World Championship.