As we have seen in the past few weeks, the crosscut can lead to furious engagements. By remaining calm, you will be able to come up with reasonable responses--if not necessarily the best moves--that will allow you to save a position from collapsing.

Crosscut

In response to a crosscut, you have three alternatives: extending, forcing atari and extending, and forcing atari twice and fixing your position. Other moves often lead to large-scale battles. Now, let us consider what is in it for the person who initiates the crosscut.

Diagram 1: After black 1, White may attach at 2, followed by black 3. At this point, White can cut with 4. This is a crosscut as the stones of both players are split. Since it is Black's turn, he should have an advantage. Why would White initiate a crosscut if he knows it will put him at a disadvantage?

Diagram 2: The crosscut is often used to sacrifice one stone to help the overall position of a player. Last week, we looked at this situation. After White approaches with 2 and Black pincers with 3, White crosscuts with 4 and 6. We should now look at this problem from White's point of view.

Diagram 3: There are two correct responses with entirely different results. One of them is the sequence through 12. Now, changing our perspective and looking from White's point of view, it becomes clear that White sacrificed not just one, but both of his crosscutting stones. His aim was to strengthen his marked stone and attack the marked black stone.

Solutions to last week's problems

Solution 1A: The problem was how White should respond to Black's crosscut (the marked black stones)? If we use the principle of extending your most important stone, white 1 is the safe answer. In the sequence through 7, Black manages to strengthen his original stones by sacrificing one of his crosscut stones. Black can even switch elsewhere. On the other hand, White's position is also strong and he has gained more territory, so he is satisfied. But even so, his marked stone may look a little too close to his other stones--this stone could have been at A or even at B.

Solution 1B: White can also force two atari with 1 and 3, then connect at 5. However, as you can see this quickly leads to a furious battle. After black 10, White has two alternatives, 1C and 1D.

Solution 1C: (Black 14 connects where the marked white stone was captured.) White can follow this diagram only if the ladder is good. After black 16, White can set up a ladder with A or B. Black collapses.

Solution 1D: (White 15 captures two stones where the marked stone was captured.) However, if the ladder is bad, White has to resort to this sequence. He gets thickness but Black gets a lot of territory in an area where he was weak.

Reference 1: White can also try 1 and 3, but Black retorts with 4 through 8. If the ladder is bad, White has to defend with 9. Black captures the corner with the combination of 10 and 12 and White collapses.

Solution 2: After Black crosscuts with 1 and 3, White must cut off the marked black stone with 4 and 6. Next, connecting at 8 is essential. This aims at pulling out his stone with 9. Therefore, Black captures with 9, allowing White to cover his last weakness with 10. White is aiming at A, which Black would have to answer with B, cutting off Black's corner from the outside world. To prevent this, black 13 is necessary, although this allows White to extend at 14. Locally, this gives White a good result.

Problem: This situation sometimes occurs. White has to reduce Black's framework with 1. Black 2 is a standard response. White 3 and 5 now form a good combination. Remember his aim is to establish a foothold in Black's moyo. How should White respond?

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.