Life and Death
Last week, we learned the go proverb: Eight lives, six dies. The problem is that most groups are not in books. Usually, problem groups are seven stones long or have slightly different shapes.
Diagram 1: This white group is six stones long. It is dead even if White plays first.
Diagram 2: On the other hand, this white group is eight stones long and can survive, even if Black plays first.
Diagram 3: Groups with a length of seven stones cause many problems. But generally, whether the group survives or not depends on who plays first. In this case, if White plays at 1, he can make two eyes.
Solution to last week's problems
Let's look at these problems first as they can help us solve later problems.
Solution 1: As long as Black makes White's eye-space smaller, he will prevail. For example, if he plays at 1, and White plays at 2, Black makes the space smaller on the other side with black 3. If White defends with 4, Black hits the vital point with 5. Although White can capture with 6 and 8, he is left with false eyes. Eventually, Black can retake white 6 and 8, unless White connects. But in any case, White stays dead.
Solution 2: The same principle applies: Try to make White's eye-space smaller. White 2 is a good response, but black 3 and 5 kill the white group.
Solution 3: White 1 is a clever move. If Black plays at 2 to try to kill the white group, white 3 puts him on the spot. Black cannot connect his three stones. If he connects at A, White captures three stones with B. Capturing three stones is good enough to make the second eye. White will live.
Solution 4: Black 1 and 3 are correct. Black should not play his first move at 2. See Solution 3 for White's counter.
New Problems
Let's have a look at some corner shapes.
Problem 1: Black plays first and kills the white group. Where should he play?
Problem 2: This is similar to Problem 1, but White has an extra liberty. This changes things a bit and Black cannot use the same method. If Black plays first, where should he move and what is White's best response?
Problem 3: This is a little different. White plays and saves his group. How?
Problem 4: This is an interesting problem from a game on TV between two top pros. The combination of black 1 and 3 was a brilliant defense against the threat of white A, followed by black B and white C, after White has exchanged 6 for 7. Black did not feel like defending against the cut at A. Keeping in mind that the players have only 30 seconds per move, he came up with the great combination of 1 and 3. Let's see how this works next week.
Want to find out more? Come to Ben's Cafe in Takadanobaba, Tokyo (03-3202-2445 or www.benscafe.com), where the English-speaking go community congregates every Sunday. You can enjoy free lessons, 11 a.m.-1 p.m.
Van Zeijst is a four-time European go champion and European representative at the Fujitsu World Championship.