In the animal world ...

By Rob Van Zeijst

In the animal world, predators often stay with their mothers to train in hunting techniques. As their prey are generally equipped with features that allow them to detect their enemy and escape, predators have to outsmart them by working together or in packs. Lions, for example, will frighten their prey so they run into the path of other lions lying in wait. Predators are not always successful and sometimes go days without eating. But, as in go, they have to learn coordination and techniques, and, most important, have a purpose.

Hints for improving your game

Purpose is the key word here, and cutting and threatening to cut are important techniques in this respect. Let us have a look at some cutting techniques in the game we started last week between Cho U (Black) and Norimoto Yoda in the second round for the Oza title in 2003.

Diagram 1 (35-71): When White plays hane (diagonal connecting stone) with the marked stone, Black abruptly cuts with 35. The moves through 43 follow naturally, but 44 and 46 seem out of place. However, these moves have a deeper meaning (see Reference 1). Instead of these moves, the usual idea would be to connect with 1 in Reference 2. After white 44 and 46, the right side is too large to sacrifice; therefore, Black has no choice but to play outside with 47 and 51. In Reference 2, the meaning of 52 and 53 become clear. White 54 is an exquisite move (see Reference 3). The sequence through 70 is almost forced. Black A would be honte (proper move), but believing he is behind, Black plays at 71. We will continue this game next week.

Reference 1 (Black plays 11 at 8): If Black cuts with 1, White would play the combination of 2 and 4. If Black wants to capture these stones he must play at 5, but White has a great combination of 6 through 14. After that, Black could play at A, but White would then connect at B and win the semeai (capturing race). If Black decides to cut at B, this would be followed by white A, black C and white D. White would capture four black stones, which would be a disaster for Black.

Reference 2: If White defends with 1, a Black play at A would lead to White connecting at B. Therefore, Black would probably sacrifice his stones by forcing the sequence through 9 to take sente (initiative). White's right side looks huge but Black can play C, followed by white D and black E, with White playing at B in sente later. At the same time, his center wall generates influence throughout the board.

Reference 3: After black 1, white 2 is an excellent move. If Black plays at 3, white 4, 6 and 8, and then 10 through 14 are formidable combinations, leading to a snapback. Black cannot capture 14, because White would recapture immediately, and he cannot defend all of his stones either. In other words, Black's corner dies.

Diagram 2: Not every cut is of equal significance. Which of the cuts A, B or C is most important? How many points is it worth for White to cut at any of these points?

Diagram 3: A kills the marked stones and is worth 20 points; B is worth minus one point, because White will defend at D to make two eyes. The cut at C is worthless because Black's groups above and below it are both alive with two eyes, indicated by the crosses.

Solutions to Dec. 22 problem

Solution 1A: After 1, the threat of cutting at A, followed by black B and white C is very real, because Black D is not sente (White does not need to defend at E). To defend against white A, Black must reinforce at 2.

Solution 1B: When White extends to 1, Black can also extend to 2. This is because there is no direct threat of a cut at A, followed by black B and white C. If White does cut there, Black would descend to D, forcing White to defend at E, and then playing at F, followed by white G and black H. These white cutting stones will die as we discussed last week.

New problem

Problem 1: There are a variety of cuts here--at A, B and C. Which cut is most important? Where should Black play his next move?

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.