Life In 19x19

I've been working on the Graded Go Problems for Beginners vol. 1, and just started working through Cho Chikun's Encyclopedia of Life and Death problems. I'm really struggling with reading through problems with a lot of options, and I don't know how to approach those problems.

As an example, consider the following problem from the first page of the Encyclopedia (black to move):

Click Here To Show Diagram Code

[go]$$B
$$ -------------------------------
$$ - . . . . . . . . . . . . . . .
$$ - . X X X X . . . . . . . . . .
$$ - . O O O O O O O . . . . . . .
$$ - . . . . . . . . . . . . . . .
$$ - . O . . . . . . . . . . . . .
$$ - . . . . . . . . . . . . . .[/go]

I don't see many forcing moves in this problem (by which I mean moves that immediately threaten an atari or capture), so I am struggling to figure out how to work through this problem. Put simply, there are too many options to consider and I don't know how to whittle them down so that I'm reading through a manageable number of options.

How should I approach a problem like this?

philosophyandgo wrote:I've been working on the Graded Go Problems for Beginners vol. 1, and just started working through Cho Chikun's Encyclopedia of Life and Death problems. I'm really struggling with reading through problems with a lot of options, and I don't know how to approach those problems.

As an example, consider the following problem from the first page of the Encyclopedia (black to move):

$$B
$$ -------------------------------
$$ - . . . . . . . . . . . . . . .
$$ - . X X X X . . . . . . . . . .
$$ - . O O O O O O O . . . . . . .
$$ - . . . . . . . . . . . . . . .
$$ - . O . . . . . . . . . . . . .
$$ - . . . . . . . . . . . . . .

Click Here To Show Diagram Code

[go]$$B
$$ -------------------------------
$$ - . . . . . . . . . . . . . . .
$$ - . X X X X . . . . . . . . . .
$$ - . O O O O O O O . . . . . . .
$$ - . . . . . . . . . . . . . . .
$$ - . O . . . . . . . . . . . . .
$$ - . . . . . . . . . . . . . .[/go]

I don't see many forcing moves in this problem (by which I mean moves that immediately threaten an atari or capture), so I am struggling to figure out how to work through this problem. Put simply, there are too many options to consider and I don't know how to whittle them down so that I'm reading through a manageable number of options.

How should I approach a problem like this?

This problem is about eyes and eyespace. There are two basic areas to play: to the right and the left of the black stones. What happens when Black plays on one side or the other. What happens when White plays first?

The problem can be simplified. Basically, Black is confined to the corner. The problem is not 'Black to live or escape', but simply 'Black to live'.

So the aim is to make two eyes. Assuming you know what this entails and can differentiate a real eye from a false one, the problem becomes simpler. Since Black's group of stones is on the second line and cannot go higher, there are only two moves to consider in order to maximize eye space:

Click Here To Show Diagram Code

[go]$$B
$$ -------------------------------
$$ - . . . . . . . . . . . . . . .
$$ - a X X X X b . . . . . . . . .
$$ - . O O O O O O O . . . . . . .
$$ - . . . . . . . . . . . . . . .
$$ - . O . . . . . . . . . . . . .
$$ - . . . . . . . . . . . . . .[/go]

In order to live, growing your eye space should be your first thought. Then you read out the natural answers to either move. Let's start with 'b'. White Blocks outside. Black expands his eye space and White tries to take it away. These problems train you to think about both living and killing. The hane is a natural killing tool, so...

Click Here To Show Diagram Code

[go]$$B
$$ -------------------------------
$$ - . a b . 5 4 . . . . . . . . .
$$ - 3 X X X X 1 2 c . . . . . . .
$$ - . O O O O O O O . . . . . . .
$$ - . . . . . . . . . . . . . . .
$$ - . O . . . . . . . . . . . . .
$$ - . . . . . . . . . . . . . .[/go]

Now a and b are miai to live, so Black succeeds. The next logical step is for White to take the eye away from the inside at a instead of , but after Black descends at b, the hane of White and the block of Black leaves Black alive again.

The next step is for White to take the point as his first move. To expand eye space, Black will crawl at and White can next block at c. This is what happens:

Click Here To Show Diagram Code

[go]$$B
$$ -------------------------------
$$ - . 6 7 . 8 . 5 . . . . . . . .
$$ - 2 X X X X 1 3 4 . . . . . . .
$$ - . O O O O O O O . . . . . . .
$$ - . . . . . . . . . . . . . . .
$$ - . O . . . . . . . . . . . . .
$$ - . . . . . . . . . . . . . .[/go]

Black dies. Reversing which side Black descends on will only change the side at which White hanes. Nevertheless, it's an important difference and should be read out. Then you can decide what happens when Black descends directly at after White's .

After reading a few more variations you will rule out Black's first move as a viable way to make life and instead try our other original choice:

Click Here To Show Diagram Code

[go]$$B
$$ -------------------------------
$$ - . . . . . . . . . . . . . . .
$$ - 1 X X X X . . . . . . . . . .
$$ - . O O O O O O O . . . . . . .
$$ - . . . . . . . . . . . . . . .
$$ - . O . . . . . . . . . . . . .
$$ - . . . . . . . . . . . . . .[/go]

The idea here is to get to know the basic moves that are played to expand and split eye space, and the basic moves that are used to reduce eye space and remove possibilities for splitting and to force false eyes. Then you try them in sequence. You try every sequence until you find a first move that unconditionally lets achieve your objective. Once all your opponent's possible responses result in your goals being achieved, you've solved the problem.

This is the foolproof way to read. Of course with experience you will simply 'know' that some moves will not work, and it will save you the effort of reading through a few of the sequences. Knowing shapes and techniques will help greatly as well.

In Cho Chikun's books, the arrangement of stones on the outside is largely irrelevant (though make sure to count the liberties!), and the group nearest the edge is simply closed in and forced to find a way to live. The goal of the group on the outside is to kill the enclosed group. In that respect, don't worry about escaping, and focus solely on making/destroying eyes.

I hope this helps.

Here is how experienced players approach this problem.

Click Here To Show Diagram Code

[go]$$Bc Diagram 1
$$ -------------------------------
$$ - C C C C . . . . . . . . . . .
$$ - B X X X X . . . . . . . . . .
$$ - . O O O O O O O . . . . . . .
$$ - . . . . . . . . . . . . . . .
$$ - . O . . . . . . . . . . . . .
$$ - . . . . . . . . . . . . . .[/go]

Click Here To Show Diagram Code

[go]$$B Diagram 2
$$ -------------------------------
$$ - . . C C C . . . . . . . . . .
$$ - . X X X X B . . . . . . . . .
$$ - . O O O O O O O . . . . . . .
$$ - . . . . . . . . . . . . . . .
$$ - . O . . . . . . . . . . . . .
$$ - . . . . . . . . . . . . . .[/go]

First, the efficient way to approach life and death is to look for eyes; that is, to look at the empty points. Diagrams 1 and 2 show what they see for two simple possibilities.

Experienced players know that in general larger eye spaces provide more possibilities for eyes. So Diagram 1 looks better than Diagram 2.

Experienced players know that the point directly underneath the last stone on the second line cannot be counted on for eyes.

Click Here To Show Diagram Code

[go]$$B Diagram 3
$$ -------------------------------
$$ - C C C C B . . . . . . . . . .
$$ - X X X X X W . . . . . . . . .
$$ - . O O O O O O O . . . . . . .
$$ - . . . . . . . . . . . . . . .
$$ - . O . . . . . . . . . . . . .
$$ - . . . . . . . . . . . . . .[/go]

Therefore, without even thinking about the exchange, - , they see the four points of eye space.

Experienced players also know that four empty points in a row in a solidly connected eye is good enough to live.

Click Here To Show Diagram Code

[go]$$B Diagram 4
$$ -------------------------------
$$ - . W B . X . . . . . . . . . .
$$ - X X X X X O . . . . . . . . .
$$ - . O O O O O O O . . . . . . .
$$ - . . . . . . . . . . . . . . .
$$ - . O . . . . . . . . . . . . .
$$ - . . . . . . . . . . . . . .[/go]

Having seen the exchange, - , in the past, they know that Black can make two eyes and live if White tries to kill. (By symmetry, even an inexperienced player can see that Black can live if White starts at the point. )

How this helps a rank beginner I am not sure. If you do not already know that four empty points in a row is alive, it is harder to find the solution than if you do. But brute force search is plainly inefficient. I would suggest trying to picture a successful outcome and then seeing if you can reach it. And that means looking at empty points.

Click Here To Show Diagram Code

[go]$$B Solution
$$ -------------------------------
$$ - . 4 5 . 3 . . . . . . . . . .
$$ - 1 X X X X 2 . . . . . . . . .
$$ - . O O O O O O O . . . . . . .
$$ - . . . . . . . . . . . . . . .
$$ - . O . . . . . . . . . . . . .
$$ - . . . . . . . . . . . . . .[/go]

Most books would only show the first three moves of the solution, assuming that the solver can see the rest.

When a proble seems too big to handle I often try to split it up and start by making just one eye and then see if I have room left over to make another.

In the case of this problem it's obviously going to be split in to an eye on the left and an eye on the right, so I'd start by thinking what do I need to do to complete the left eye?

If black extends to the left...

Click Here To Show Diagram Code

[go]$$B
$$ -------------------------------
$$ - . 2 3 . . . . . . . . . . . .
$$ - 1 X X X X . . . . . . . . . .
$$ - . O O O O O O O . . . . . . .
$$ - . . . . . . . . . . . . . . .
$$ - . O . . . . . . . . . . . . .
$$ - . . . . . . . . . . . . . .[/go]

2 and 3 could be reversed, but the point is that black needs those three spaces to guarantee an eye, which means that...

Click Here To Show Diagram Code

[go]$$B
$$ -------------------------------
$$ - . O X . a . . . . . . . . . .
$$ - X X X X X b . . . . . . . . .
$$ - . O O O O O O O . . . . . . .
$$ - . . . . . . . . . . . . . . .
$$ - . O . . . . . . . . . . . . .
$$ - . . . . . . . . . . . . . .[/go]

He has enough space to to create an eye with a and if white plays there he can create more space with b, so a and b are miai for the final eye.

After this discovery I'd check it by reading the right eye first, and also repeat the whole process to see what happens if black starts by extending to the right.

I don't think the two books mentioned are at the same level. Maybe look at Cho Elementary after completing Graded Go Problems for Beginners II? Or even III? The Cho Chikun stuff is pretty inconsistent in difficulty.

Some of us lazier (oops! I meant 'more efficient' of course) experienced players fall back on learned rules such as [sl=SixDieButEightLive]'eight live and six die'[/sl]. Since we have only four stones to start with, there is no way we will make life by extending toward the center, e.g. F18, etc. So we must take the corner. If we play A18 are we alive? Yes, so can we play A17 instead and still live if White throws in at A18? No, so we have to settle for A18.

ez4u wrote:Some of us lazier (oops! I meant 'more efficient' of course) experienced players fall back on learned rules such as [sl=SixDieButEightLive]'eight live and six die'[/sl]. Since we have only four stones to start with, there is no way we will make life by extending toward the center, e.g. F18, etc. So we must take the corner. If we play A18 are we alive? Yes, so can we play A17 instead and still live if White throws in at A18? No, so we have to settle for A18.

In the easily accessible English literature, this kind of rule can be found in James Davies' Life and Death. This is a classic. I'd recommend any DDK get it even if it will be some time before it can be entirely grasped.

philosophyandgo wrote:just started working through Cho Chikun's Encyclopedia of Life and Death problems

I wouldn't bother. Most of them are far too hard for a DDK, even the elementary ones. It's actually very hard to make life and death problems for beginners, in my opinion, because life and death involves an awful lot of brute-force reading (which is hard) and shape recognition (which needs experience).

In particular, when I see this problem, I don't try reading out the possibilities. I call upon my knowledge that, if black plays into the corner, he gets a safe eye, but if white plays into the corner, white can break that eye. (Unlike the other side, where black extending will get more eyespace, but white can't break an eye so easily.) There's no way for you to have this knowledge yet, so you're forced to perform large amounts of brute-force reading. Yuck.

I second Davies's "Life and Death", but even that may be too hard, depending on your strength. If that is too hard, try working through this website: http://playgo.to/iwtg/en/ and just playing lots until you get more experience.

philosophyandgo wrote:I've been working on the Graded Go Problems for Beginners vol. 1, and just started working through Cho Chikun's Encyclopedia of Life and Death problems. I'm really struggling with reading through problems with a lot of options, and I don't know how to approach those problems.
...

IMO, you are supposed to struggle with these problems, and that's OK. Keep working at it until you can solve it. If it doesn't get anywhere, try an easier problem.

But if you are struggling, that's not a bad thing. You are gaining insight into why things do or don't work.

If you're working on Graded Go Problems for Beginners Vol. 1, Cho Chikun's Life and Death is like stepping from little league tee-ball to high school or college level baseball in one bound. It won't be easy. Honestly, Graded Go Problems for Beginners Volumes 2 and 3 will probably hold you in good stead for a while after, and make the later jump easier since you will have more reading practice.

One move which probably should have been included in Phoenix's answer and wasn't is the hane at the 3-1 point. First reaction for a beginner might be that it expands even more than the 2-1 point. But that is an illusion: W throws in at 2-1 and B dies.

DrStraw wrote:One move which probably should have been included in Phoenix's answer and wasn't is the hane at the 3-1 point. First reaction for a beginner might be that it expands even more than the 2-1 point. But that is an illusion: W throws in at 2-1 and B dies.

he mentioned the false eyes

I didn't spot this being mentioned, apologies if it was.

One thing that helped me get around this position was the idea that a play on the second line against the edge was worth two plays on the right here going out into the board. The reason is with the play to the side on the left the edge acts as two black stones sealing that side and making the point at 1,1 a potential eye, whereas a play on the other direction doesn't give you this because White's block on the second line makes that point under your last stone not potential eyespace.


This doesn't answer the problem for you immediately, but when you see a problem like this one you know to first read out the descent to the side first before other moves as its quite often (in a case with a line of stones on the 2nd line) how you make life.

Bill Spight wrote:Here is how experienced players approach this problem.

There might be another way for unexperienced players:

Click Here To Show Diagram Code

[go]$$Bc Diagram 1
$$ -------------------------------
$$ - . . C C . . . . . . . . . . .
$$ - . X X X X . . . . . . . . . .
$$ - . O O O O O O O . . . . . . .
$$ - . . . . . . . . . . . . . . .
$$ - . O . . . . . . . . . . . . .
$$ - . . . . . . . . . . . . . .[/go]

Black has one eye for sure.

Click Here To Show Diagram Code

[go]$$B Diagram 2
$$ -------------------------------
$$ - ? . C C ? . . . . . . . . . .
$$ - . X X X X . . . . . . . . . .
$$ - . O O O O O O O . . . . . . .
$$ - . . . . . . . . . . . . . . .
$$ - . O . . . . . . . . . . . . .
$$ - . . . . . . . . . . . . . .[/go]

But where is the second one ? On the left, or on the right ?