Life and death
There is a go proverb that goes: Eight lives, six dies. Of course, there are groups of six stones that survive while groups of eight or 10, or even 50, stones die. In fact, this proverb is about a very specific situation--but one that appears obscure.
Diagram 1: The white group is six stones long, but it will die regardless of who plays first.
Diagram 2: White 1 is an attempt by White to keep his group alive. However, black 2 and 4 make sure this does not happen.
Diagram 3: Here, the white group is eight stones long and it will remain alive, irrespective of whose turn it is.
Diagram 4: The moves 1 through 5 are a standard attack on White's eye-space and eye-shape. However, even if White just answers each move, he can stay alive.
New Problems
If six will die and eight will remain alive, what about seven?
Problem 1: If Black plays first, he can kill the white group. Where should he play?
Problem 2: By playing first, Black can kill the White stones. How?
Problem 3: Where should White play to keep his group alive?
Problem 4: This problem is similar to Problem 3, but the result is very different. If Black plays first, the White stones are doomed. Where should Black play?
Solution to last week's problems
Solution 1: (Black 5 is played at the marked black stone spot) Black 1 is correct. This is the only way to kill the white group. After white 2, black 3 makes a second eye here impossible. White 4 can capture two stones, but Black can play where the marked black stone was captured, turning this space into a false eye.
Reference 1: Black 1 is a mistake. If White blocks with 2, black 3 does not work. White will capture three stones with 4 and no matter what Black does next, White will get an eye there.
Solution 2: (Black 5 is played at the marked black stone spot) After seeing Solution 1, this problem is easy to solve. Black 1 and 3 are the right combination. White can capture two stones with 4, but Black plays 5 and takes away White's second eye, thereby killing White.
Solution 3: Black 1 is the move that kills the white group unconditionally. White 6 needs to be answered with 7.
Because Black is so thick on the outside, he can afford to play at 9 to turn this space into a false eye. In response to 10, black 11 will kill the entire white group. Note black 1 is the only move that enables him to play at 11. Neither player, 4- and 5-dan pros, came up with this play.
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.