The meaning of the stratagem "beat the grass to startle the snake” in mili-tary affairs is: if you want to discover an enemy that is in hiding, then you must reconnoiter suspicious areas. Reconnaissance is the primary factor leading to the discovery of intelligence about the enemy. The phrase itself tells us that to attack one person, you frighten the general populace. For application to Go, we can explain this stratagem as follows. When we begin an attack, we intentionally reveal our objective. This revelation startles our opponent, and he sets about trying to protect himself. Then we gain some profit seemingly out of nowhere, without even realizing it.
Basic Figure: Chosen from the 1985 All-China Individual Go Tournament.
White to play. It is very obvious that Black has an unsettled group in the center. It appears that with White making the first move, Black is in serious danger.
But White also has to watch his weak points (see Diagram 1).
Diagram 1: Black played tobi on the first line at +, threatening to start a ko with the sequence to 9, breaking White apart. But right now, when White takes the ko Black cannot find a suitable ko threat anywhere. So for the time being White isn't worried; but, in the final analysis there is a defect here.
Diagram 2: The invasion at White 1 is a common maneuver, and a severe move locally! But presently the focus of the game is the group in
the center. If White plays this way, he will be pressed down by Black 2. Then Black will give up two stones to connect with the center group.
Although White does gain a lot, the play in Diagram 1 is White's burden. White would be a little uneasy, so this result is not adequate for him. White can also consider taking one stone at a to reduce the number of ko threats on the board. This is a relatively negative way to play, because the
play at a is not very efficient. After a Black tobi at b, the central. group is suddenly alive, and there is a strong possibility that White's attack would come up empty. White has lost control.
White needs to choose a positive way of playing. Invading the side, al-lowing Black to connect and forcing himself to patch up his own position, is certainly not superior play. It gives Black a new lease on life.
Figure 1-Actual Game Continuation: The keima at White 1 cut Black apart. It initiated an attack on Black's central group, and simultaneously attacked Black's group on the side. This is what we mean by “beating the grass to startle the snake”. Black was frightened into looking after two groups at the same time. White played tightly with the hane at 9, forming
a thick wall in the center. This constituted a serious threat to Black's central group. Under heavy attack by White, Black was forced to start a ko fight on the left side, resulting in furi-kawari that settled the center.
After White resolved the ko, he killed the corner with tobi at 25, gaining extremely large profit. In this trade, White obviously came out better in actual territory.
Figure 2 - Actual Game Continuation: The resistance from Black 26 on was useless.
After White played the tsuke-shita at 29, the Black corner was simply dead. Black 32 repaired the defect in the corner, such that after this move, there was basically no way to attack that corner. White should have played oki at 35 rather than atari at 33. But Black 34 was also bad -he should have played hiki at 38.
In the actual game, after Black blocked at 34, the oki at White 35 again succeeded. After that, both sides played rather normal yose through 51, with the game about even on the board. But Black had the burden of komi, so White
was sure to win. The main reason White gained a winning position was that through a strong, fierce attack Black's big dragon was frightened.
Harried by the need to look after two weak groups, he sought refuge in a ko fight. White gained considerable profit from the ko fight, steadily moving along the road to victory.
Diagram 3: Black strengthening the right side rather than starting a ko fight would be a good fighting attitude. But naturally White would ignore this and carry out an attack on Black anyway. The capture at White 13, eliminating a ko threat, is a strong move! Black supports his position with kosumi at 14. After the exchange of White 15 for Black 16, making good use of some tactics against the Black corner rather than continuing the attack is a higher order of play.
Because White has suddenly made
himself thicker, he can implement a strong attack against Black. More-over, Black has no good way to answer the two tsuke of 17 and 19. He can only let White grab some profit. This way, White smoothly builds up his own strength.
Tsuke at 33 is a tough move! Black's big dragon sinks into difficulties. The cut at 37 and atari at 39 enable White to make life. The ensuing variation is the strongest continuation for both sides, and after 55, Black is cut off and his big dragon is dead. After the tsuke at 17, if Black retreats, or if the corner territory is destroyed, then White can win without any need to kill Black.
Conclusion: In this game, White had the initiative. If White had missed the opportunity to attack, allowing Black to escape, then the ko on the side would be a constant burden. White would find it difficult to main-tain control of the game.
In the actual game, White instituted a large-scale attack against Black, utilizing the stratagem of “beat the grass to startle the snake”. He inten-tionally frightened Black. After this, Black could not sit still, starting a ko fight on the left side. White used this burden of resolving the ko to fash-ion an exchange. From this he gained sure profit, paving the road to vic-tory.