Joseki - Revision history

Selinger: Cleanup

2024-03-09T20:09:07Z

Cleanup

Selinger: Converted the remaining 5th row josekis to Red's point of view.

2024-03-09T19:59:08Z

Converted the remaining 5th row josekis to Red's point of view.

Selinger: Started converting 5th row josekis to Red's point of view (up to B4).

2024-03-09T14:24:51Z

Started converting 5th row josekis to Red's point of view (up to B4).

Selinger: Rewrote 4th row josekis from Red's point of view.

2024-03-09T14:08:50Z

Rewrote 4th row josekis from Red's point of view.

Selinger: Added a link.

2022-08-28T23:15:02Z

Added a link.

Selinger: Added some links

2022-04-26T23:07:43Z

Added some links

Selinger: Added "See also"

2022-02-24T18:37:08Z

Added "See also"

Demer: /* Obtuse corner play */ "obtuse corners plays" -> "obtuse corner plays"

2021-01-03T21:23:49Z

‎Obtuse corner play: "obtuse corners plays" -> "obtuse corner plays"

Selinger: Added category

2020-12-28T20:58:11Z

Added category

Selinger: /* 4th row opening */ Fixed more typos

2020-12-16T14:36:04Z

‎4th row opening: Fixed more typos

@@ Line 64: / Line 64: @@
     edges="bottom right"
     contents="R 1:h7 B 2:h8 R 3:g8"
     /><br/>
 '''A2)'''
@@ Line 71: / Line 70: @@
     edges="bottom right"
     contents="R 1:h7 B 2:h8 R 3:i7 B 4:i8 R 5:g8"
     /><br/>
 '''A3)'''
@@ Line 78: / Line 76: @@
     edges="bottom right"
     contents="R 1:h7 B 2:h8 R 3:i7 B 4:i9 R 5:j8 B 6:j9 R 7:g8 B 8:f10 R 9:i8 B 10:h9 R 11:e9 B 12:c10 R 13:c11 B 14:f8 R 15:f9"
     /><br/>
 '''B1)'''
@@ Line 85: / Line 82: @@
     edges="bottom right"
     contents="R 1:h7 B 2:h9 R 3:i9 B 4:h10 R 5:i10 E *:h8,i8"
     /><br/>
 '''B2)'''
@@ Line 92: / Line 88: @@
     edges="bottom right"
     contents="R 1:h7 B 2:h9 R 3:i9 B 4:h10 R 5:i10 B 6:i8 R 7:j6 B 8:j7 R 9:g9 B 10:e10 R 11:e11 B 12:g8 R 13:h8"
     /><br/>
@@ Line 102: / Line 97: @@
     edges="bottom right"
     contents="R 1:h7 B 2:h9 R 3:i9 B 4:h10 R 5:i10 B 6:i8 R 7:j6 B 8:j7"
     /><br/>
 '''B4)'''
@@ Line 109: / Line 103: @@
     edges="bottom right"
     contents="R 1:h7 B 2:h9 R 3:i9 B 4:h10 R 5:i10 B 6:i8 R 7:j6 B 8:j7 R 9:g9 B 10:e10 R 11:e11 B 12:g8 E *:h8"
     /><br/>
 '''C)'''
@@ Line 116: / Line 109: @@
     edges="bottom right"
     contents="R 1:h7 B 2:h9 R 3:j9 B 4:j8 R 5:g9"
     /><br/>
 '''D1)'''
@@ Line 123: / Line 115: @@
     edges="bottom right"
     contents="R 1:h7 B 2:h9 R 3:j6 E *:g10,h8"
     /><br/>
 '''D2)'''
@@ Line 130: / Line 121: @@
     edges="bottom right"
     contents="R 1:h7 B 2:h9 R 3:j6 B 4:g10 R 5:i8 B 6:j9"
     /><br/>
 '''D2a)'''
@@ Line 139: / Line 129: @@
     edges="bottom right"
     contents="R 1:h7 B 2:h9 R 3:j6 B 4:i6 R 5:i7 B 6:g10 E +:h8"
     /><br/>
 '''D3)'''
@@ Line 146: / Line 135: @@
     edges="bottom right"
     contents="R 1:h7 B 2:h9 R 3:j6 B 4:h8 R 5:j9 B 6:j8"
     /><br/>
 '''D4)'''
@@ Line 153: / Line 141: @@
     edges="bottom right"
     contents="R 1:h7 B 2:h9 R 3:j6 B 4:h8 R 5:j9 B 6:j8 R 7:g8"
     /><br/>
 '''E)'''
@@ Line 160: / Line 147: @@
     edges="bottom right"
     contents="R 1:h7 B 2:h9 R 3:i9 B 4:i8 R 5:g9 E *:g10"
     /><br/>
 '''F1)'''
@@ Line 167: / Line 153: @@
     edges="bottom right"
     contents="R 1:h7 B 2:g8 R 3:h8 B 4:g9 R 5:h9"
     /><br/>
 '''F2)'''
@@ Line 174: / Line 159: @@
     edges="bottom right"
     contents="R 1:h7 B 2:g8 R 3:i8 B 4:h9 R 5:i9 B 6:h10 R 7:i10"
     /><br/>

@@ Line 115: / Line 115: @@
     coords="hide"
     edges="bottom right"
-    contents="B 1:g8 R 2:i8 B 3:i10 R 4:h10 B 5:i7"
+    contents="R 1:h7 B 2:h9 R 3:j9 B 4:j8 R 5:g9"
     /><br/>
 '''D1)'''
@@ Line 121: / Line 122: @@
     coords="hide"
     edges="bottom right"
-    contents="B 1:g8 R 2:i8 B 3:f10 E *:j7 E *:h8"
+    contents="R 1:h7 B 2:h9 R 3:j6 E *:g10,h8"
     /><br/>
 '''D2)'''
@@ Line 127: / Line 129: @@
     coords="hide"
     edges="bottom right"
-    contents="B 1:g8 R 2:i8 B 3:f10 R 4:j7 B 5:h9 R 6:i10"
+    contents="R 1:h7 B 2:h9 R 3:j6 B 4:g10 R 5:i8 B 6:j9"
     /><br/>
 '''D2a)'''
-The following joseki is preferable (for Red) to D2, because by playing 4 before 6, Blue does not get the cell marked "+". If Red played the equivalent of 4 after joseki D2, Blue would get "+".
+The following joseki is preferable (for Blue) to D2, because by playing 4 before 6, Red does not get the cell marked "+". If Blue played the equivalent of 4 after joseki D2, Red would get "+".
 <hexboard size="11x11"
     coords="hide"
     edges="bottom right"
-    contents="B 1:g8 R 2:i8 B 3:f10 R 4:f9 B 5:g9 R 6:j7 E +:h8"
+    contents="R 1:h7 B 2:h9 R 3:j6 B 4:i6 R 5:i7 B 6:g10 E +:h8"
     /><br/>
 '''D3)'''
@@ Line 141: / Line 145: @@
     coords="hide"
     edges="bottom right"
-    contents="B 1:g8 R 2:i8 B 3:f10 R 4:h8 B 5:i10 R 6:h10"
+    contents="R 1:h7 B 2:h9 R 3:j6 B 4:h8 R 5:j9 B 6:j8"
     /><br/>
 '''D4)'''
@@ Line 147: / Line 152: @@
     coords="hide"
     edges="bottom right"
-    contents="B 1:g8 R 2:i8 B 3:f10 R 4:h8 B 5:i10 R 6:h10 B 7:h7"
+    contents="R 1:h7 B 2:h9 R 3:j6 B 4:h8 R 5:j9 B 6:j8 R 7:g8"
     /><br/>
 '''E)'''
@@ Line 153: / Line 159: @@
     coords="hide"
     edges="bottom right"
-    contents="B 1:g8 R 2:i8 B 3:i9 R 4:h9 B 5:i7 E *:j7"
+    contents="R 1:h7 B 2:h9 R 3:i9 B 4:i8 R 5:g9 E *:g10"
     /><br/>
 '''F1)'''
@@ Line 159: / Line 166: @@
     coords="hide"
     edges="bottom right"
-    contents="B 1:g8 R 2:h7 B 3:h8 R 4:i7 B 5:i8"
+    contents="R 1:h7 B 2:g8 R 3:h8 B 4:g9 R 5:h9"
     /><br/>
 '''F2)'''
@@ Line 165: / Line 173: @@
     coords="hide"
     edges="bottom right"
-    contents="B 1:g8 R 2:h7 B 3:h9 R 4:i8 B 5:i9 R 6:j8 B 7:j9"
+    contents="R 1:h7 B 2:g8 R 3:i8 B 4:h9 R 5:i9 B 6:h10 R 7:i10"
     /><br/>

@@ Line 63: / Line 63: @@
     coords="hide"
     edges="bottom right"
-    contents="B 1:g8 R 2:h8 B 3:h7"
+    contents="R 1:h7 B 2:h8 R 3:g8"
     /><br/>
 '''A2)'''
@@ Line 69: / Line 70: @@
     coords="hide"
     edges="bottom right"
-    contents="B 1:g8 R 2:h8 B 3:g9 R 4:h9 B 5:h7"
+    contents="R 1:h7 B 2:h8 R 3:i7 B 4:i8 R 5:g8"
     /><br/>
 '''A3)'''
@@ Line 75: / Line 77: @@
     coords="hide"
     edges="bottom right"
-    contents="B 1:g8 R 2:h8 B 3:g9 R 4:i9 B 5:h10 R 6:i10 B 7:h7 R 8:j6 B 9:h9 R 10:i8 B 11:i5 R 12:j3 B 13:k3 R 14:h6 B 15:i6"
+    contents="R 1:h7 B 2:h8 R 3:i7 B 4:i9 R 5:j8 B 6:j9 R 7:g8 B 8:f10 R 9:i8 B 10:h9 R 11:e9 B 12:c10 R 13:c11 B 14:f8 R 15:f9"
     /><br/>
 '''B1)'''
@@ Line 81: / Line 84: @@
     coords="hide"
     edges="bottom right"
-    contents="B 1:g8 R 2:i8 B 3:i9 R 4:j8 B 5:j9 E *:h8 E *:h9"
+    contents="R 1:h7 B 2:h9 R 3:i9 B 4:h10 R 5:i10 E *:h8,i8"
     /><br/>
 '''B2)'''
@@ Line 87: / Line 91: @@
     coords="hide"
     edges="bottom right"
-    contents="B 1:g8 R 2:i8 B 3:i9 R 4:j8 B 5:j9 R 6:h9 B 7:f10 R 8:g10 B 9:i7 R 10:j5 B 11:k5 R 12:h7 B 13:h8"
+    contents="R 1:h7 B 2:h9 R 3:i9 B 4:h10 R 5:i10 B 6:i8 R 7:j6 B 8:j7 R 9:g9 B 10:e10 R 11:e11 B 12:g8 R 13:h8"
     /><br/>
@@ Line 96: / Line 101: @@
     coords="hide"
     edges="bottom right"
-    contents="B 1:g8 R 2:i8 B 3:i9 R 4:j8 B 5:j9 R 6:h9 B 7:f10 R 8:g10"
+    contents="R 1:h7 B 2:h9 R 3:i9 B 4:h10 R 5:i10 B 6:i8 R 7:j6 B 8:j7"
     /><br/>
 '''B4)'''
@@ Line 102: / Line 108: @@
     coords="hide"
     edges="bottom right"
-    contents="B 1:g8 R 2:i8 B 3:i9 R 4:j8 B 5:j9 R 6:h9 B 7:f10 R 8:g10 B 9:i7 R 10:j5 B 11:k5 R 12:h7 E *:h8"
+    contents="R 1:h7 B 2:h9 R 3:i9 B 4:h10 R 5:i10 B 6:i8 R 7:j6 B 8:j7 R 9:g9 B 10:e10 R 11:e11 B 12:g8 E *:h8"
     /><br/>
 '''C)'''

@@ Line 14: / Line 14: @@
     coords="hide"
     edges="bottom right"
-    contents="B 3:h6 B 1:f7 R 2:h7"
+    contents="R 1:g6 B 2:g8 R 3:f8"
     /><br/>
 '''A2)'''
-Red wants an escape on the bottom, Blue wants an escape on the top '''and Blue knows that Red wants an escape on the bottom'''.<br/>
+Red wants an escape on the bottom, Blue wants an escape on the top '''and Red knows that Blue wants an escape on the top'''.<br/>
-The move #3 is an improvement, because in some cases Blue might get an additional free escape on the bottom.<br/>
+The move #3 is an improvement, because in some cases Red might get an additional free escape on the top.<br/>
-There is risk involved. If Red made an error on move #2 and in truth he wanted an escape on top he can correct the error by playing a different move #4.
+There is risk involved. If Blue made an error on move #2 and in truth he wanted an escape on bottom he can correct the error by playing a different move #4.
 <hexboard size="9x9"
     coords="hide"
     edges="bottom right"
-    contents="B 5:h6 B 1:f7 R 2:h7 B 3:g8 R 4:h8"
+    contents="R 1:g6 B 2:g8 R 3:h7 B 4:h8 R 5:f8"
     /><br/>
@@ Line 32: / Line 32: @@
     coords="hide"
     edges="bottom right"
-    contents="B 5:g6 B 1:f7 R 2:g7 B 3:f8 R 4:g8"
+    contents="R 1:g6 B 2:g7 R 3:h6 B 4:h7 R 5:f7"
     /><br/>
 '''C)'''
 This position might be reached if both players want an escape on the top.<br/>
-Blue keeps a future option of playing in the cell marked with an asterisk.<br/>
+Red keeps a future option of playing in the cell marked with an asterisk.<br/>
-This is a very risky plan by Blue, because Red has additionally got an escape on bottom. Blue should only play this joseki if he is certain that Red cannot use the escape on bottom. Otherwise a reasonable option is to give up the strong escape on top and go for position '''B)'''.
+This is a very risky plan by Red, because Blue has additionally got an escape on top. Red should only play this joseki if she is certain that Blue cannot use the escape on top. Otherwise a reasonable option is to give up the strong escape on the bottom and go for position '''B)'''.
 <hexboard size="9x9"
     coords="hide"
     edges="bottom right"
-    contents="B 3:g6 B 1:f7 R 2:g7 E *:e8"
+    contents="R 1:g6 B 2:g7 R 3:f7 E *:h5"
     /><br/>
 '''D)'''
-If both players want an escape on bottom we get an unusual position where Red plays the last move of the joseki.<br/>
+If both players want an escape on top we get an unusual position where Blue plays the last move of the joseki.<br/>
-Blue's plan is to get a cell marked with an asterisk for free in future, so he shouldn't play there immediately. What he should do depends on the play in rest of the board.
+Red's plan is to get the cell marked with an asterisk for free in future, so she shouldn't play there immediately. What she should do depends on the play on the rest of the board.
 <hexboard size="9x9"
     coords="hide"
     edges="bottom right"
-    contents="B 1:f7 E *:g7 R 2:h7 B 3:g8 R 4:h8"
+    contents="R 1:g6 B 2:g8 R 3:h7 B 4:h8 E *:g7"
     /><br/>

@@ Line 196: / Line 196: @@
    contents="R 1:d4 B 2:e5 R 3:c4 B 4:c5 R 5:d5 B 6:d6 R 7:b5"
    />
-The corner is now settled; neither Red nor Blue has a ladder escape, and both Red and Blue have gained some territory, with Red's territory being more useful.
+The corner is now [[settled region|settled]]; neither Red nor Blue has a ladder escape, and both Red and Blue have gained some territory, with Red's territory being more useful.
 Alternatively, if Blue's objective was to gain a ladder escape, then Blue plays as follows. Both players end up with 2nd row ladder escapes and some territory, with Red's territory being more useful.

@@ Line 2: / Line 2: @@
 == Joseki's logic ==
-When player A makes a move in a corner, she dominates the territory around this corner. Assuming that she picked her best strategy, she should stick to it and always defend her domination in the area. However, that doesn't mean that player B should give up that territory. Playing elsewhere will sometimes lead to losing the initiative around the aforementioned corner, so instead, player B counterplays in the corner. A game progresses in this manner: player B counterplays, player A holds on to her domination, player B counterplays again etc... This usually lasts 2-10 moves by each player, depending on how far from an edge the first move by player A was. When the final position is reached, player A has a fixed escape on one side of the corner and player B has a fixed escape on the other side (the second player's escape is always of shorter range).
+When player A makes a move in a corner, she dominates the territory around this corner. Assuming that she picked her best strategy, she should stick to it and always defend her domination in the area. However, that doesn't mean that player B should give up that territory. Playing elsewhere will sometimes lead to losing the [[initiative]] around the aforementioned corner, so instead, player B counterplays in the corner. A game progresses in this manner: player B counterplays, player A holds on to her domination, player B counterplays again etc... This usually lasts 2-10 moves by each player, depending on how far from an edge the first move by player A was. When the final position is reached, player A has a fixed escape on one side of the corner and player B has a fixed escape on the other side (the second player's escape is always of shorter range).
-Playing a joseki can often be delayed. This is a good choice if a player isn't sure which joseki is favourable for them. However, it's important to make sure that one gets the initiative back to play joseki. If the opponent can make [[Forcing moves|forcing]] moves in other areas of the board then a chance to delay joseki is gone.
+Playing a joseki can often be delayed. This is a good choice if a player isn't sure which joseki is favourable for them. However, it's important to make sure that one gets the [[initiative]] back to play joseki. If the opponent can make [[Forcing moves|forcing]] moves in other areas of the board then a chance to delay joseki is gone.
 In the below examples, when we say "Red has an escape on the bottom" or "Blue has an escape on the top", we mean a [[ladder escape]] for certain ladders (e.g., 2nd row ladder, 3rd row ladder). When we say "Blue has an escape on the bottom", we mean that Blue ''denies'' Red a ladder escape there, i.e., Blue, as the [[ladder handling|defender]] of the ladder along the red edge, will "win" the ladder.
@@ Line 178: / Line 178: @@
    contents="R 1:d4 E a:b5 b:c5 c:d5 d:e5 e:b6 f:e4"
    />
-This move is quite strong; it is already connected to the red edge by [[edge template IV1d]], it gives Red 2nd-to-4th and 3rd-to-5th row [[Switchback#A4 switchback|switchbacks]] for ladders along the bottom edge, and it also blocks a significant part of the blue edge. Blue does not have any very good intrusions into the corner. For example, if Blue plays at a, Blue gets 2nd and 3rd row ladder escapes, but since Blue is not in Red's template, Red gains the initiative. If Blue plays at b or c, Red can push to f, gaining significant territory, while Blue gets at best a 2nd row ladder escape. If Blue plays at e, Red has a good response at b, limiting Blue to a 2nd row ladder escape. A reasonable move for Blue is d. Red can respond as follows:
+This move is quite strong; it is already connected to the red edge by [[edge template IV1d]], it gives Red 2nd-to-4th and 3rd-to-5th row [[Switchback#A4 switchback|switchbacks]] for ladders along the bottom edge, and it also blocks a significant part of the blue edge. Blue does not have any very good intrusions into the corner. For example, if Blue plays at a, Blue gets 2nd and 3rd row ladder escapes, but since Blue is not in Red's template, Red gains the [[initiative]]. If Blue plays at b or c, Red can push to f, gaining significant territory, while Blue gets at best a 2nd row ladder escape. If Blue plays at e, Red has a good response at b, limiting Blue to a 2nd row ladder escape. A reasonable move for Blue is d. Red can respond as follows:
 <hexboard size="7x7"
    coords="none"
@@ Line 187: / Line 187: @@
 Note that Red is connected to the bottom edge by [[edge template IV2a]]. Red also has an escape for 2nd row ladders along the bottom edge, and some territory. Blue has nothing very valuable, so it makes sense for Blue to make another move. There are two things Blue may hope to accomplish: take away Red's ladder escape, or create a ladder escape for Blue.
-If Blue wants to take away Red's ladder escape while keeping the initiative, it seems reasonable for Blue to play at x; however, in this case, Red can reconnect at y, gaining significant territory and probably leaving Blue worse off. A better move for Blue is z. This forces Red to reconnect at w, and ''then'' Blue can play x. Red still gains some territory, but less than if Blue had played at x immediately.
+If Blue wants to take away Red's ladder escape while keeping the [[initiative]], it seems reasonable for Blue to play at x; however, in this case, Red can reconnect at y, gaining significant territory and probably leaving Blue worse off. A better move for Blue is z. This forces Red to reconnect at w, and ''then'' Blue can play x. Red still gains some territory, but less than if Blue had played at x immediately.
 '''A1)'''

@@ Line 207: / Line 207: @@
    contents="R 1:d4 B 2:e5 R 3:c4 B 4:b5 R 5:c6"
    />
 [[category: Advanced Strategy]]

@@ Line 163: / Line 163: @@
 == Obtuse corner play ==
-In the [[Board#Corners|obtuse corners]], play is not yet as codified as in the acute corners, and there are no obtuse corner josekis per se. Nevertheless, there are certain obtuse corners plays that are common, and some responses are better than others.
+In the [[Board#Corners|obtuse corners]], play is not yet as codified as in the acute corners, and there are no obtuse corner josekis per se. Nevertheless, there are certain obtuse corner plays that are common, and some responses are better than others.
 This section is under construction; more material should be added here.

← Older revision		Revision as of 20:58, 28 December 2020
Line 207:		Line 207:
	contents="R 1:d4 B 2:e5 R 3:c4 B 4:b5 R 5:c6"		contents="R 1:d4 B 2:e5 R 3:c4 B 4:b5 R 5:c6"
	/>		/>
		+
		+	[[category: Advanced Strategy]]

@@ Line 185: / Line 185: @@
    contents="R 1:d4 B 2:e5 R 3:c4 E x:d6 y:b4 z:c5 w:d5"
    />
-Note that Red is connected to the bottom edge by [[edge template IV2a]]. Red also has an escape for 2nd row ladders along the bottom edge, and some territory. Blue has nothing very valuable, so it makes sense for Blue to make another move. There are two things Blue hope to accomplish: take away Red's ladder escape, or create ladder escape for Blue.
+Note that Red is connected to the bottom edge by [[edge template IV2a]]. Red also has an escape for 2nd row ladders along the bottom edge, and some territory. Blue has nothing very valuable, so it makes sense for Blue to make another move. There are two things Blue may hope to accomplish: take away Red's ladder escape, or create a ladder escape for Blue.
 If Blue wants to take away Red's ladder escape while keeping the initiative, it seems reasonable for Blue to play at x; however, in this case, Red can reconnect at y, gaining significant territory and probably leaving Blue worse off. A better move for Blue is z. This forces Red to reconnect at w, and ''then'' Blue can play x. Red still gains some territory, but less than if Blue had played at x immediately.