Newsgroups: rec.games.go
Date: Wed, 15 Apr 1992 18:50:30 -0400 
From: Victor Lin <vl11+@andrew.cmu.edu>
Subject: Re: Go Problem
	<1992Apr11.172002.15508@umbc3.umbc.edu>

In article <1992Apr11.172002.15508@umbc3.umbc.edu>
wangs@sol.engr.umbc.edu (Shawe-Shiuan Wang) writes:

>> This is the first time I post something on net, and I am trying to
>> post some common problems ocurring frequently in real games.
>>  
>> Go Problem 1: White plays next move  
>> . . . . . . . . . . . . . . . . . . .
>> . . . O . . . . . . . . . . . . . . .
>> . . X . . O 1 . O . X . . . . . . . .
>> . . . X . . . . . . . . . . . . . . .
>> . . . . . . . . . . . . . . . . . . .
>> . . . X . . . . . . . . . . . . . . .
>> . . . . . . . . . . . . . . . . . . .
>> . . . . . . . . . . . . . . . . . . .
>  
>  Go Problem 1: White plays next move  
>  . . . . . . . . . . . . . . . . . . .
>  . . . O . . . . . . . . . . . . . . .
>  . . X . . O X 2 O . X . . . . . . . .
>  . . . X . . . . . . . . . . . . . . .
>  . . . . . . . . . . . . . . . . . . .
>  . . . X . . . . . . . . . . . . . . .
>  . . . . . . . . . . . . . . . . . . .
>  . . . . . . . . . . . . . . . . . . .
> 

Problem 1 is not a really well-designed problem.
The solution to the problem depends on the surroundings.

Solution 1a:

  Go Problem 1: White plays next move  
  . . . . . 8 . . . . . . . . . . . . .
  . . . O 6 5 4 . . . . . . . . . . . .
  . . X . a O X 2 O . X . . . . . . . .
  . . . X . 7 3 . . . . . . . . . . . .
  . . . . . . . . . . . . . . . . . . .
  . . . X . . . . . . . . . . . . . . .
  . . . . . . . . . . . . . . . . . . .
  . . . . . . . . . . . . . . . . . . .

This is the solution given by Jeffrey Wang, but black can create thickness
as shown above.

Black 5 at 7 is also acceptible.  If white plays a, then black 5.

Solution 1b:

  Go Problem 1: White plays next move  
  . . . . . . . . . . . . . . . . . . .
  . . . O b 3 2 . . . . . . . . . . . .
  . . X . 5 O X 6 O . X . . . . . . . .
  . . . X . 7 4 . . . . . . . . . . . .
  . . . . . . . . . . . . . . . . . . .
  . . . X . . . . . . . . . . . . . . .
  . . . . . . . . . . . . . . . . . . .
  . . . . . . . . . . . . . . . . . . .

In this alternative solution white refuses to let black build thickness.

Black 7 is played when black has enough ko-threats (strong against ko's)
and wants to threaten the white group.
  
Black 7 at b is less complicated (the territory at the corner is pretty 
much guaranteed).  It, however, asserts less pressure on the white group.
Depending on the surroundings, the black stone on the top may be attacked.

This is an example of the problem with a lot of go books, especially the  
problem sets for the beginners.  When playing go, one should always look
at the whole board.  Do not limit your vision to just a corner.  The same
go problem could have four or five different solutions depending on the 
setting.  

The same can be said about joseki's.  The problem with a lot of amateur
players is that they blindly follow the same joseki, without thinking 
whether that particular joseki is appropriate at that situation.  If it
isn't, one should try another joseki.  Sometimes a non-joseki may fit
better than all the joseki's.  This is how new joseki's are developed.
Many old books about joseki mislead players by providing outdated info
and make people think that there is only one way to play go.  Go is a
much deeper game.  Remember, one can have a disadvantage at a corner,
playing non-joseki moves, but the positioning of the stones may give 
him/her the overall advantage.     
 
>> Go Problem 2: White plays next move 
>> . . . . . . . . . . . . . . . . . . .
>> . . . . . . . . . . . . . . . . . . .
>> . . O X . O . . . . . . . . . . . . .
>> . . O X . . . . . X . . . . . . . . .
>> . . 1 . . . . . . . . . . . . . . . .
>> . . . . . . . . . . . . . . . . . . .
>> . . . . . . . . . . . . . . . . . . .
>> . . . . . . . . . . . . . . . . . . .
>> 1's are unprompt move(black).
> 
>  . . . . . . . . . . . . . . . . . . .
>  . . 3 1 2 . . . . . . . . . . . . . .
>  . . O X 4 O . . . . . . . . . . . . .
>  . . O X . . . . . X . . . . . . . . .
>  . . X 5 . . . . . . . . . . . . . . .
>  . . 6 7 . . . . . . . . . . . . . . .
>  . . . . . . . . . . . . . . . . . . .
>  . . . . . . . . . . . . . . . . . . .
>
> Both black groups are attacked.
 
Jeffrey's solution to problem 2 is correct.  Actually, this came up in a 
championship game between Cho and Ohtake a few years ago, if I remember
correctly.

My comments to problem 2:

  . . . . . . . . . . . . . . . . . . .
  . . 3 1 2 . . . . . . . . . . . . . .
  . . O X 4 O . . . . . . . . . . . . .
  . . O X . . . . . X . . . . . . . . .
  . 6 X 7 . . . . . . . . . . . . . . .
  . . 5 . . . . . . . . . . . . . . . .
  . . . . . . . . . . . . . . . . . . .
  . . . . . . . . . . . . . . . . . . .

White can also play 5 as shown above.  If black 6 at 7, then white 6.
Compare this diagram with the one below:

  . . . . . . . . . . . . . . . . . . .
  . . 4 2 3 . . . . . . . . . . . . . .
  . . O X 5 O . . . . . . . . . . . . .
  . . O X . . . . . X . . . . . . . . .
  . d c 1 . . . . . . . . . . . . . . .
  . . 6 . . . . . . . . . . . . . . . .
  . . . . . . . . . . . . . . . . . . .
  . . e . . . . . . . . . . . . . . . .

This is a basic joseki.  The exchange of black c and white d is VERY,
VERY BAD.  I would consider it about a loss of 10 points on black's side.
Not only does it use up a ko-threat, it also eliminate the possibility
of playing from the left side (black e, then black d threatens white).
On top of that, the exchage is a "damezumari" or "taking away your own
liberty".  With this exchange, black may be in trouble when white makes
a move in black's "potential" territory at the top.

On the other hand, black would have been better off to play: 

  . . . . . . . . . . . . . . . . . . .
  . . 3 1 2 . . . . . . . . . . . . . .
  . . O X 5 O . . . . . . . . . . . . .
  . . O X . . 6 . . X . . . . . . . . .
  . . X 4 . . . . . . . . . . . . . . .
  . . . . . . . . . . . . . . . . . . .
  . . . . . . . . . . . . . . . . . . .
  . . . . . . . . . . . . . . . . . . .

Black should connect at 4, as shown in the diagram above.  This way both
sides are fairly even, with white having a slight advantage.  Black in 
Jeffrey's solution is helpless.

If the positioning was like this:

  . . . . . . . . . . . . . . . . . . .
  . . . . . . . . . . . . . . . . . . .
  . . O X . O . X . . . . . . . . . . .
  . . O X . . . . . . . . . . . . . . .
  . . 1 . . . . . . . . . . . . . . . .
  . . . . . . . . . . . . . . . . . . .
  . . . . . . . . . . . . . . . . . . .
  . . . . . . . . . . . . . . . . . . .

then 1 is a possible move.  One example:

  . . . . . . . . . . . . . . . . . . .
  . . 4 2 6 . . . . . . . . . . . . . .
  . . O X 5 O . X . . . . . . . . . . .
  . . O X . 7 . . . . . . . . . . . . .
  . . 1 3 . . . . . . . . . . . . . . .
  . . . . . . . . . . . . . . . . . . .
  . . . . . . . . . . . . . . . . . . .
  . . . . . . . . . . . . . . . . . . .

If white 4 at 6, then black 7.
 
> These are my answers.
> 
>Jeffrey Wang 

These are my comments to your answers.
  



--------------------------------------------
Victor H. Lin		          "Life's Hell, especially if  
vl11+@andrew.cmu.edu      you make it that way!!" 
(412)681-3139			          -- V. L.
--------------------------------------------