Notes on the 1st Stratagem: Crossing the sea by Treachery - 瞒天过海

The idea behind the 1st stratagem "crossing the sea by treachery“ is to conceal a secret plan in the middle of some open affair. In other words some extremely secret contents are held in an extremely public form.

Translating this concept into an applicable Igo game play can be in the form of the following:

- The perception of perfect preparation leads to relaxed vigilance.
- The sight of common occurrences leads to slackened suspicion.
- Secret machinations are better concealed in the open than in the dark
- Extreme public exposure often contains extreme secrecy.
- Concealment is possible even though the game is entirely open.
- One can misdirect the opponent by the way one plays
- One must make extraordinary moves appear to be ordinary moves.
- Do not arouse the suspicion of the opponent.
- There may be a latent as well as an overt interpretation of anything happening on the goban.

(;FF[4]CA[UTF-8]AP[GoGui:1.4.2] KM[6.5]DT[2011-11-15] AB[di][dn][cn][do][lm][mm][nm][om][ol][mn][mo][no][nn][oo][op][nq][pq][or][qq][qp][rn][qm][qk][pk][qi][ph][pg][og][oc][qd][rl] AW[fc][cc][dg][eg][dk][co][cp][dq][fq][lo][ln][mp][mq][pi][oh][nh][ok][nk][ml][pl][pm][pn][on][pp][po][qo][ro][rp][rq][qr][rm] C[The original meaning of „crossing the sea by treachery“ is to conceal a secret plan in the middle of some open affair. Some extremely secret contents are held in an extremely public form. In Go, everything is openly laid out on the board; how can one apply this "crossing the sea by treachery” stratagem? One must make extraordinary moves appear to be ordinary moves. After all, the plans a player conceives for attack or defense are not all known to the opponent. So the player can cover his artful conception, and put it into action under conditions that do not arouse the suspicion of his opponent. In this way, he can apply the “crossing the sea by treachery" stratagem. Taken from a game in the Sixth „New Athletics Cup“ Tournament of 1984. White just invaded at "Circle" From the perspective of the whole board, Black has made more profit on the right side, but White has split up the left side, throwing the whole game into utter confusion. This is precisely the crucial moment.] PL[B]CR[dk] (;B[pr] C[Diagram 1: First, let's take a look at the life-and-death situation in the lower right corner. The guzumi of Black 1 is certainly the easiest thing to think of to destroy White's eyes. The usual reply is the sagari of White 2. Then the oki of Black 3, followed by nobi at 5 is the only way to kill the corner. If there was no relationship with the outside, this would be "bent four in the corner" and White would be dead. Not so here. The sagari of White 6 forces Black 7 to destroy White's eye, and then White 8 rescues one stone, enabling White to make another eye. Black ends in defeat.] MA;W[qs] C[Diagram 1: First, let's take a look at the life-and-death situation in the lower right corner. The guzumi of Black 1 is certainly the easiest thing to think of to destroy White's eyes. The usual reply is the sagari of White 2. Then the oki of Black 3, followed by nobi at 5 is the only way to kill the corner. If there was no relationship with the outside, this would be "bent four in the corner" and White would be dead. Not so here. The sagari of White 6 forces Black 7 to destroy White's eye, and then White 8 rescues one stone, enabling White to make another eye. Black ends in defeat.] ;B[sr] C[Diagram 1: First, let's take a look at the life-and-death situation in the lower right corner. The guzumi of Black 1 is certainly the easiest thing to think of to destroy White's eyes. The usual reply is the sagari of White 2. Then the oki of Black 3, followed by nobi at 5 is the only way to kill the corner. If there was no relationship with the outside, this would be "bent four in the corner" and White would be dead. Not so here. The sagari of White 6 forces Black 7 to destroy White's eye, and then White 8 rescues one stone, enabling White to make another eye. Black ends in defeat.] ;W[rr] C[Diagram 1: First, let's take a look at the life-and-death situation in the lower right corner. The guzumi of Black 1 is certainly the easiest thing to think of to destroy White's eyes. The usual reply is the sagari of White 2. Then the oki of Black 3, followed by nobi at 5 is the only way to kill the corner. If there was no relationship with the outside, this would be "bent four in the corner" and White would be dead. Not so here. The sagari of White 6 forces Black 7 to destroy White's eye, and then White 8 rescues one stone, enabling White to make another eye. Black ends in defeat.] ;B[ss] C[Diagram 1: First, let's take a look at the life-and-death situation in the lower right corner. The guzumi of Black 1 is certainly the easiest thing to think of to destroy White's eyes. The usual reply is the sagari of White 2. Then the oki of Black 3, followed by nobi at 5 is the only way to kill the corner. If there was no relationship with the outside, this would be "bent four in the corner" and White would be dead. Not so here. The sagari of White 6 forces Black 7 to destroy White's eye, and then White 8 rescues one stone, enabling White to make another eye. Black ends in defeat.] ;W[so] C[Diagram 1: First, let's take a look at the life-and-death situation in the lower right corner. The guzumi of Black 1 is certainly the easiest thing to think of to destroy White's eyes. The usual reply is the sagari of White 2. Then the oki of Black 3, followed by nobi at 5 is the only way to kill the corner. If there was no relationship with the outside, this would be "bent four in the corner" and White would be dead. Not so here. The sagari of White 6 forces Black 7 to destroy White's eye, and then White 8 rescues one stone, enabling White to make another eye. Black ends in defeat.] ;B[sq] C[Diagram 1: First, let's take a look at the life-and-death situation in the lower right corner. The guzumi of Black 1 is certainly the easiest thing to think of to destroy White's eyes. The usual reply is the sagari of White 2. Then the oki of Black 3, followed by nobi at 5 is the only way to kill the corner. If there was no relationship with the outside, this would be "bent four in the corner" and White would be dead. Not so here. The sagari of White 6 forces Black 7 to destroy White's eye, and then White 8 rescues one stone, enabling White to make another eye. Black ends in defeat.] ;W[sm] C[Diagram 1: First, let's take a look at the life-and-death situation in the lower right corner. The guzumi of Black 1 is certainly the easiest thing to think of to destroy White's eyes. The usual reply is the sagari of White 2. Then the oki of Black 3, followed by nobi at 5 is the only way to kill the corner. If there was no relationship with the outside, this would be "bent four in the corner" and White would be dead. Not so here. The sagari of White 6 forces Black 7 to destroy White's eye, and then White 8 rescues one stone, enabling White to make another eye. Black ends in defeat.] ) (;B[rs] C[Diagram 2: Here the vital point is the oki of Black 1. (Because White first saw that the variation in Diagram 1 resulted in a living group, in his hurry he overlooked this placement tactic.) If White responds by connecting at 11, then the hane of Black 3 forces "bent four in the corner", killing White. So the strongest resistance is kosumi at White 2. The hane of Black 3 is the correct order of moves. White has no choice but to block at 4. Then when Black crawls out at 5, the sequence up to the eye-stealing move of 11 is forced. White 12 starts a ko, and the result is that the corner can be killed in ko. (From this variation you can see that a Black kake-tsugi at „a“ is absolute sente. If White does not answer, he is unconditionally dead. With this resource in mind, we judge that the whole board position favors Black.) By the way, if Black plays 1 at 2, then a White sagari at 3 makes the corner unconditionally alive.] ;W[sr] C[Diagram 2: Here the vital point is the oki of Black 1. (Because White first saw that the variation in Diagram 1 resulted in a living group, in his hurry he overlooked this placement tactic.) If White responds by connecting at 11, then the hane of Black 3 forces "bent four in the corner", killing White. So the strongest resistance is kosumi at White 2. The hane of Black 3 is the correct order of moves. White has no choice but to block at 4. Then when Black crawls out at 5, the sequence up to the eye-stealing move of 11 is forced. White 12 starts a ko, and the result is that the corner can be killed in ko. (From this variation you can see that a Black kake-tsugi at „a“ is absolute sente. If White does not answer, he is unconditionally dead. With this resource in mind, we judge that the whole board position favors Black.) By the way, if Black plays 1 at 2, then a White sagari at 3 makes the corner unconditionally alive.] ;B[so] C[Diagram 2: Here the vital point is the oki of Black 1. (Because White first saw that the variation in Diagram 1 resulted in a living group, in his hurry he overlooked this placement tactic.) If White responds by connecting at 11, then the hane of Black 3 forces "bent four in the corner", killing White. So the strongest resistance is kosumi at White 2. The hane of Black 3 is the correct order of moves. White has no choice but to block at 4. Then when Black crawls out at 5, the sequence up to the eye-stealing move of 11 is forced. White 12 starts a ko, and the result is that the corner can be killed in ko. (From this variation you can see that a Black kake-tsugi at „a“ is absolute sente. If White does not answer, he is unconditionally dead. With this resource in mind, we judge that the whole board position favors Black.) By the way, if Black plays 1 at 2, then a White sagari at 3 makes the corner unconditionally alive.] ;W[sp] C[Diagram 2: Here the vital point is the oki of Black 1. (Because White first saw that the variation in Diagram 1 resulted in a living group, in his hurry he overlooked this placement tactic.) If White responds by connecting at 11, then the hane of Black 3 forces "bent four in the corner", killing White. So the strongest resistance is kosumi at White 2. The hane of Black 3 is the correct order of moves. White has no choice but to block at 4. Then when Black crawls out at 5, the sequence up to the eye-stealing move of 11 is forced. White 12 starts a ko, and the result is that the corner can be killed in ko. (From this variation you can see that a Black kake-tsugi at „a“ is absolute sente. If White does not answer, he is unconditionally dead. With this resource in mind, we judge that the whole board position favors Black.) By the way, if Black plays 1 at 2, then a White sagari at 3 makes the corner unconditionally alive.] ;B[qs] C[Diagram 2: Here the vital point is the oki of Black 1. (Because White first saw that the variation in Diagram 1 resulted in a living group, in his hurry he overlooked this placement tactic.) If White responds by connecting at 11, then the hane of Black 3 forces "bent four in the corner", killing White. So the strongest resistance is kosumi at White 2. The hane of Black 3 is the correct order of moves. White has no choice but to block at 4. Then when Black crawls out at 5, the sequence up to the eye-stealing move of 11 is forced. White 12 starts a ko, and the result is that the corner can be killed in ko. (From this variation you can see that a Black kake-tsugi at „a“ is absolute sente. If White does not answer, he is unconditionally dead. With this resource in mind, we judge that the whole board position favors Black.) By the way, if Black plays 1 at 2, then a White sagari at 3 makes the corner unconditionally alive.] ;W[pr] C[Diagram 2: Here the vital point is the oki of Black 1. (Because White first saw that the variation in Diagram 1 resulted in a living group, in his hurry he overlooked this placement tactic.) If White responds by connecting at 11, then the hane of Black 3 forces "bent four in the corner", killing White. So the strongest resistance is kosumi at White 2. The hane of Black 3 is the correct order of moves. White has no choice but to block at 4. Then when Black crawls out at 5, the sequence up to the eye-stealing move of 11 is forced. White 12 starts a ko, and the result is that the corner can be killed in ko. (From this variation you can see that a Black kake-tsugi at „a“ is absolute sente. If White does not answer, he is unconditionally dead. With this resource in mind, we judge that the whole board position favors Black.) By the way, if Black plays 1 at 2, then a White sagari at 3 makes the corner unconditionally alive.] ;B[ps] C[Diagram 2: Here the vital point is the oki of Black 1. (Because White first saw that the variation in Diagram 1 resulted in a living group, in his hurry he overlooked this placement tactic.) If White responds by connecting at 11, then the hane of Black 3 forces "bent four in the corner", killing White. So the strongest resistance is kosumi at White 2. The hane of Black 3 is the correct order of moves. White has no choice but to block at 4. Then when Black crawls out at 5, the sequence up to the eye-stealing move of 11 is forced. White 12 starts a ko, and the result is that the corner can be killed in ko. (From this variation you can see that a Black kake-tsugi at „a“ is absolute sente. If White does not answer, he is unconditionally dead. With this resource in mind, we judge that the whole board position favors Black.) By the way, if Black plays 1 at 2, then a White sagari at 3 makes the corner unconditionally alive.] ;W[oq] C[Diagram 2: Here the vital point is the oki of Black 1. (Because White first saw that the variation in Diagram 1 resulted in a living group, in his hurry he overlooked this placement tactic.) If White responds by connecting at 11, then the hane of Black 3 forces "bent four in the corner", killing White. So the strongest resistance is kosumi at White 2. The hane of Black 3 is the correct order of moves. White has no choice but to block at 4. Then when Black crawls out at 5, the sequence up to the eye-stealing move of 11 is forced. White 12 starts a ko, and the result is that the corner can be killed in ko. (From this variation you can see that a Black kake-tsugi at „a“ is absolute sente. If White does not answer, he is unconditionally dead. With this resource in mind, we judge that the whole board position favors Black.) By the way, if Black plays 1 at 2, then a White sagari at 3 makes the corner unconditionally alive.] LB[mr:a]) (;B[ck] C[Diagram 3: Now let's look at the left side. Striking underneath at Black 1 followed by the cut at 3 is a common method for shinogi, but this sort of method is not suitable in this position. This is because the three Black atones on the lower side have a comfortable escape route, and are certainly not in any peril. White plays ate at 4 and 6, cutting off the Black stone just above 8. When Black plays magari at 9, White securely seals him in with 10. That leaves Black no choice but to capture one stone with 11, allowing White to connect at 12. The result of this variation is that White has become extremely thick and the two Black stones on the upper half of the board have no room to maneuver. Black fails.] ;W[cl] C[Diagram 3: Now let's look at the left side. Striking underneath at Black 1 followed by the cut at 3 is a common method for shinogi, but this sort of method is not suitable in this position. This is because the three Black atones on the lower side have a comfortable escape route, and are certainly not in any peril. White plays ate at 4 and 6, cutting off the Black stone just above 8. When Black plays magari at 9, White securely seals him in with 10. That leaves Black no choice but to capture one stone with 11, allowing White to connect at 12. The result of this variation is that White has become extremely thick and the two Black stones on the upper half of the board have no room to maneuver. Black fails.] (;B[dl] C[Diagram 3: Now let's look at the left side. Striking underneath at Black 1 followed by the cut at 3 is a common method for shinogi, but this sort of method is not suitable in this position. This is because the three Black atones on the lower side have a comfortable escape route, and are certainly not in any peril. White plays ate at 4 and 6, cutting off the Black stone just above 8. When Black plays magari at 9, White securely seals him in with 10. That leaves Black no choice but to capture one stone with 11, allowing White to connect at 12. The result of this variation is that White has become extremely thick and the two Black stones on the upper half of the board have no room to maneuver. Black fails.] ;W[el] C[Diagram 3: Now let's look at the left side. Striking underneath at Black 1 followed by the cut at 3 is a common method for shinogi, but this sort of method is not suitable in this position. This is because the three Black atones on the lower side have a comfortable escape route, and are certainly not in any peril. White plays ate at 4 and 6, cutting off the Black stone just above 8. When Black plays magari at 9, White securely seals him in with 10. That leaves Black no choice but to capture one stone with 11, allowing White to connect at 12. The result of this variation is that White has become extremely thick and the two Black stones on the upper half of the board have no room to maneuver. Black fails.] ;B[dm] C[Diagram 3: Now let's look at the left side. Striking underneath at Black 1 followed by the cut at 3 is a common method for shinogi, but this sort of method is not suitable in this position. This is because the three Black atones on the lower side have a comfortable escape route, and are certainly not in any peril. White plays ate at 4 and 6, cutting off the Black stone just above 8. When Black plays magari at 9, White securely seals him in with 10. That leaves Black no choice but to capture one stone with 11, allowing White to connect at 12. The result of this variation is that White has become extremely thick and the two Black stones on the upper half of the board have no room to maneuver. Black fails.] ;W[cj] C[Diagram 3: Now let's look at the left side. Striking underneath at Black 1 followed by the cut at 3 is a common method for shinogi, but this sort of method is not suitable in this position. This is because the three Black atones on the lower side have a comfortable escape route, and are certainly not in any peril. White plays ate at 4 and 6, cutting off the Black stone just above 8. When Black plays magari at 9, White securely seals him in with 10. That leaves Black no choice but to capture one stone with 11, allowing White to connect at 12. The result of this variation is that White has become extremely thick and the two Black stones on the upper half of the board have no room to maneuver. Black fails.] ;B[bk] C[Diagram 3: Now let's look at the left side. Striking underneath at Black 1 followed by the cut at 3 is a common method for shinogi, but this sort of method is not suitable in this position. This is because the three Black atones on the lower side have a comfortable escape route, and are certainly not in any peril. White plays ate at 4 and 6, cutting off the Black stone just above 8. When Black plays magari at 9, White securely seals him in with 10. That leaves Black no choice but to capture one stone with 11, allowing White to connect at 12. The result of this variation is that White has become extremely thick and the two Black stones on the upper half of the board have no room to maneuver. Black fails.] ;W[dj] C[Diagram 3: Now let's look at the left side. Striking underneath at Black 1 followed by the cut at 3 is a common method for shinogi, but this sort of method is not suitable in this position. This is because the three Black atones on the lower side have a comfortable escape route, and are certainly not in any peril. White plays ate at 4 and 6, cutting off the Black stone just above 8. When Black plays magari at 9, White securely seals him in with 10. That leaves Black no choice but to capture one stone with 11, allowing White to connect at 12. The result of this variation is that White has become extremely thick and the two Black stones on the upper half of the board have no room to maneuver. Black fails.] ;B[bj] C[Diagram 3: Now let's look at the left side. Striking underneath at Black 1 followed by the cut at 3 is a common method for shinogi, but this sort of method is not suitable in this position. This is because the three Black atones on the lower side have a comfortable escape route, and are certainly not in any peril. White plays ate at 4 and 6, cutting off the Black stone just above 8. When Black plays magari at 9, White securely seals him in with 10. That leaves Black no choice but to capture one stone with 11, allowing White to connect at 12. The result of this variation is that White has become extremely thick and the two Black stones on the upper half of the board have no room to maneuver. Black fails.] ;W[bi] C[Diagram 3: Now let's look at the left side. Striking underneath at Black 1 followed by the cut at 3 is a common method for shinogi, but this sort of method is not suitable in this position. This is because the three Black atones on the lower side have a comfortable escape route, and are certainly not in any peril. White plays ate at 4 and 6, cutting off the Black stone just above 8. When Black plays magari at 9, White securely seals him in with 10. That leaves Black no choice but to capture one stone with 11, allowing White to connect at 12. The result of this variation is that White has become extremely thick and the two Black stones on the upper half of the board have no room to maneuver. Black fails.] ;B[bl] C[Diagram 3: Now let's look at the left side. Striking underneath at Black 1 followed by the cut at 3 is a common method for shinogi, but this sort of method is not suitable in this position. This is because the three Black atones on the lower side have a comfortable escape route, and are certainly not in any peril. White plays ate at 4 and 6, cutting off the Black stone just above 8. When Black plays magari at 9, White securely seals him in with 10. That leaves Black no choice but to capture one stone with 11, allowing White to connect at 12. The result of this variation is that White has become extremely thick and the two Black stones on the upper half of the board have no room to maneuver. Black fails.] ;W[ci] C[Diagram 3: Now let's look at the left side. Striking underneath at Black 1 followed by the cut at 3 is a common method for shinogi, but this sort of method is not suitable in this position. This is because the three Black atones on the lower side have a comfortable escape route, and are certainly not in any peril. White plays ate at 4 and 6, cutting off the Black stone just above 8. When Black plays magari at 9, White securely seals him in with 10. That leaves Black no choice but to capture one stone with 11, allowing White to connect at 12. The result of this variation is that White has become extremely thick and the two Black stones on the upper half of the board have no room to maneuver. Black fails.] ) (;B[bk];W[bl];B[dl];W[dj];B[cj];W[ek];B[dm];W[ci];B[bi];W[ch] ;B[bh];W[bg];B[bm] (;W[ak];AE[ak]PL[W]) (;W[aj];B[bj];W[fj]))))

References:
-  Thirty-six Stratagems Applied to Go(1996), Publisher Yutopian
- http://senseis.xmp.net/?path=SecretArtOfWar&page=CrossTheSeaUnderCamouflage