Although go is thousands of years old, ...
By Rob Van Zeijst
Although go is thousands of years old, both tactics and strategy are changing faster than ever before. The main reasons are a rapid rise in the game's popularity in South Korea and China and the spread of the Internet, which allows players to get news of and implement the latest moves and strategies immediately.
As the game was formerly played at a high level only in Japan, the Japanese way of thinking dominated the go scene. However, that has changed in the past decade. Another change has been in the komi system, which allows for a 5.5-point compensation for White because Black always plays first. The half point was to prevent draws. Despite this compensation, Black's winning percentage was around 53 percent among professionals, so many of them would rather be Black. White was always playing a catch-up game. To counter this, the komi has been raised to 6.5 points in most tournaments. This one point difference has caused a revolution in opening strategies as Black must try harder to take the lead.
Opening game
With a komi of 5.5 points, most Black players felt they were ahead of the game from the start. However, with a komi of 6.5, the number of professionals who want to play White has increased significantly. In other words, Black has to search for new moves to increase the efficiency of his stones. How well the stones work together determines the efficiency of the moves.
Diagram 1: Here three groups of black stones each surround 9 points of territory. However, the number of stones used in each case is different. The corner group A uses 7 stones, while group B on the side has 11 stones and the center group C needs 15 stones, more than twice those in group A. It is easy to see that stones in the corner make territory more easily than along the sides. And it is much more difficult to make territory in the center.
Diagram 2: The previous diagram is a theoretical case. To work out how the same logic applies in reality is more difficult. The positions here might be a close representation. The positions A, B and C all comprise about 12 points of territory. However, the stones at A are more likely to make territory than those at C. This clearly shows stones in the corner make territory more easily.
Diagram 3: As mentioned last week, this is the most common corner enclosure. The go term for corner enclosure is shimari.
Diagram 4: This shimari appears to enclose more territory, but it has a lot of weaknesses such as A, B and C, which become especially apparent when White moves around D or E. If White plays around D or E, Black will usually have to add a move to reinforce the corner, which lowers efficiency.
Diagram 5: The Japanese opening frequently used to feature the standard shimari shown in Diagram 3. That approach started to change when the Chinese fuseki became popular in Japan about 30 years ago. This fuseki comprises the moves 1, 3 and 5 (or 5 at A) regardless of where White plays his stones on the left side. The idea is to encourage White to invade at B and attack that stone. In other words, this fuseki is much more aggressive than simply playing a standard shimari.
Diagram 6: The idea of playing three stones in a row on one side is not new. The pattern 1, 3 and 5 with three stones on the star points of one side is called sanrensei, and this strategy has been popular for at least 40 years. As you can see, black 5 is an extension from 1 as well as from 3 and as such has more synergy than a regular extension. However, Black should not expect the entire right side to become his territory as White can invade easily. Prime candidates for such an invasion are A and B, and, to a lesser extent, C and D.
Diagram 7: Not satisfied with mere synergy, South Korea's top players introduced this pattern that is now popular around the world. The expansive nature of Black 5 and 7 encourage White to invade around 8. Black then has the option of pressuring white 8 from the top with A (or B or C) and attack the white group to develop the lower side. Black can also expand directly with a move around D (or E or F). In either case, the idea is to develop the lower side in a natural way--while attacking--without having to play at G or H. This would save a stone that can be used elsewhere to build up Black's development around the board. This is an aggressive approach and often leads to large-scale battle.
Van Zeijst is a four-time European go champion and European representative at the Fujitsu World Championship.