Life In 19x19

To me these aren't too bad because at the end there are only ~2 liberties left that matter. I have a harder time with large capture races, where there are still tactics left that obscure the actual number of liberties. So you have to read out a few short tactical sequences in different areas of the dragons, and then count liberties of a position that isn't actually on the board.

John Fairbairn wrote:I would also like to stress that the chunks I have identified for the index are there to help readers find related problems, because there are rather many in the book (almost 500). I have no idea whether they are all genuinely useful for learning life and death. Maybe the book will help us find out.

Chunking has long been known as a way that memory works. It has also been used (with somewhat different meaning) in problem solving. (See SOAR.) I feel sure that the chunks you have identified, John, will help people improve their tesuji and life & death.

Clustering the problems may be very useful to the reader.

During the years of editing German Go Journal's Problem Corner, I got the feeling that many solvers are not aware of vital points and vital shape elements, which could give a clue to the solution.

See attachment for a resulting idea of mine.

Cassandra wrote:vital points and vital shape elements

In tsumego, what do you consider "vital points and vital shape elements", which types do exist and how in general can they be determined, IYO?

See attachment for a resulting idea of mine.

Some very nice presentational ideas in that.

John Fairbairn wrote:

See attachment for a resulting idea of mine.

Some very nice presentational ideas in that.

Thanks.

Hwang InSeong 7d evaluated the idea of having a step "hints" between problem and solution (the latter usually not being included in Korean books) as "interesting idea", which he had not seen before.

I suppose that some (or many ?) of my hints have to be taken with a grain of salt, because he also mentioned that he often could give even better (or more adequate) hints.

RobertJasiek wrote:

Cassandra wrote:vital points and vital shape elements

In tsumego, what do you consider "vital points and vital shape elements", which types do exist and how in general can they be determined, IYO?

Hi, Robert,

when starting with the idea I tried to find some "clusters" or "types" to put the problems into, but I was not happy at all with the results. So my work ended in "hints" only, showing the solver where probably to look at.

I suppose that "clustering" the problems will be the more difficult the higher the level of the problems is. Because the problems are more "open" (e. g. often with more points to start with) and vital points and shapes will clearly materialise later in the solution sequence.

In my experience, cruical elements to look at are mainly "where could a Nakade shape arise" and "where could false eyes arise". Especially the latter seems to be underestimated by many players, I suppose.

In the problems setup, elements of false eyes (either three points in one diagonal or three points in "v" shape) - i. e. the board points necessary to build one - usually cannot be seen "completed". Often they will be build during the solution sequence.

Shapes of false eyes will often result in Damezumari or Oiotoshi, too.

In higher level problems, more attention has to be paid to some helping (or hindering) stones in the surrounding, e. g. a Sagari to the edge.

Another element in several problems is the need to increase the liberties of a group.

Often there can be seen one point, when taken by the "opponent" (should it be his turn), would "close" the problem in the sense that the "attacker" could play two moves in a row and even be unable to reach the aim of the problem. In those cases move 1 should be evident.

Often the "opponent" has more than one option for this "closing" move, but only one of those will be the correct starting point for the "attacker". In any case it will be helpful to think about the problem from the opponents side.

Or - like in the problem given at the beginning of this thread - there is only one real choice for move 1 and the "true" challenge will arise later.

+ + + + + + + + + +

If you are interested in, I could email you the PDFs of my three "books" on this topic (about 5 MB each).

Since your PDF books might or might not be interesting for me, I would indeed want to look at them, thank you!

Your descriptions are a mess but my studies so far aren't any less messy, at least on the global problem solution scale. Also for me problems with different "levels" of progress create the greatest difficulty.

What I have started to do is classifying problem move types. E.g., I have found 2-atari (atari in 2 moves) to be useful in some scarce problems. (No useful 3-atari outside semeais yet... I.e. the classics are not as difficult as very cute problems of the 121-hardness could be.) You get to such things in case of iteration of multiple threats.

Then there is an approach of assessing remaining nakade space by first making all space reductions where the defender will have to fill / reinforce.

Finding problem classes will be more difficult. I have not even worked through All About Life and Death for that purpose yet. Even the basic (and only local) problems contain more structure than one wishes to fear.

Move order is another great difficulty. The typical 12! problem is quite complex at a first glance.

Cassandra wrote:
See attachment for a resulting idea of mine.

I like this idea quite alot. I have on occasion tried to do something similar for myself, by taking problems that are too difficult for me, but to which I have a solution, and then making a new problem by including the first move and saving it as an SGF to try later. Of course this has the drawback, that I've looked at the solution, but luckily I'm good at forgetting . In any case your approach is very nice. Thanks for sharing!

RobertJasiek wrote:Since your PDF books might or might not be interesting for me, I would indeed want to look at them, thank you!

Not to reopen the discussion but.
I like your logic here, Robert, "Since True or False, .... "

To me, I don't have too much trouble solving this problem once it happens, but I'm still at the stage that I don't know if it's reasonable before I play it. As black I might try to play to avoid this cut. As white, I might assume that I've killed some stones.

I really must say that I get great satisfaction out of reading something like this out and then watch my opponent play the sequence out until he realizes what I know.

It's also funny to have realized that the opponent can do something to you and you sigh and wait for them to destroy you until you realize that they didn't take advantage, so you have time to protect. Or the best is when they try the wrong sequence and fix your shape for you. Then you feel like you robbed them.

Of course, sometimes you missed something and you end up feeling like a dunce.

More whining

I stared at this problem for 30 minutes this morning before I convinced myself it would work. I even had the correct sequence of moves for both players for most of that time (my mind kept gravitating back to it, which is good I guess), but it didn't look like it would work.

It's the same issue: counting liberties of an imaginary position seems to require more mental prowess than I currently possess. I can read out much more complicated positions if stones are only added and there aren't any liberty counting issues. And I can read out some pretty intense capture races. But I just don't have enough mental registers to do both at the same time

Bleh, I'll keep practicing it I guess.

Middle of three stones? ^^

aurik wrote:I would think those are both automatic for any SDK. But, at least at my level, at some point the shortage of liberties become obscured even by a "one-way street" sequence of moves.

$$Bc
$$ -----------------------+
$$ . . . . . . . . . . . |
$$ . . . . O X . . . . . |
$$ . . . O . X . X X . . |
$$ . O . O . O . O X . . |
$$ . . . . X O . O X . . |
$$ . . . . X X . O X . . |
$$ . . . X . O . O X . . |
$$ . . . . . . O X . . . |
$$ . O . O . O . X . . . |
$$ . , . . . . . , . . . |

Click Here To Show Diagram Code

[go]$$Bc
$$ -----------------------+
$$ . . . . . . . . . . . |
$$ . . . . O X . . . . . |
$$ . . . O . X . X X . . |
$$ . O . O . O . O X . . |
$$ . . . . X O . O X . . |
$$ . . . . X X . O X . . |
$$ . . . X . O . O X . . |
$$ . . . . . . O X . . . |
$$ . O . O . O . X . . . |
$$ . , . . . . . , . . . |[/go]

At what level of reading do you think the answer to this derivative problem becomes reflex / instant?

In my case, just by looking at this problem, I definitely feel that a tesuji is there in the shape. However, for some reason, the first sequence I read was this one:

Click Here To Show Diagram Code

[go]$$Bc
$$ -----------------------+
$$ . . . . . . . . . . . |
$$ . . . . O X . . . . . |
$$ . . . O 2 X . X X . . |
$$ . O . O 1 O 4 O X . . |
$$ . . . . X O 3 O X . . |
$$ . . . . X X . O X . . |
$$ . . . X . O . O X . . |
$$ . . . . . . O X . . . |
$$ . O . O . O . X . . . |
$$ . , . . . . . , . . . |[/go]

which doesn't work, and led me to think of this one immediately after:

Click Here To Show Diagram Code

[go]$$Bc
$$ -----------------------+
$$ . . . . . . . . . . . |
$$ . . . . O X . . . . . |
$$ . . . O 2 X . X X . . |
$$ . O . O 1 O 3 O X . . |
$$ . . . . X O 4 O X . . |
$$ . . . . X X . O X . . |
$$ . . . X . O 5 O X . . |
$$ . . . . . . O X . . . |
$$ . O . O . O . X . . . |
$$ . , . . . . . , . . . |[/go]

I guess it's kind of weird, because it was easy to notice that there was a weakness in the shape for me, but the first sequence I read was the one that didn't work.

$$Bc
$$ -----------------------+
$$ . . . . . . . . . . . |
$$ . . . . O X . . . . . |
$$ . . . O . X X X X . . |
$$ . O . . . O O O X . . |
$$ . . . . X . . . X . . |
$$ . . . . X . O . X . . |
$$ . . . X . O . . . . . |
$$ . . . . . . O . X . . |
$$ . O . O . O . X . . . |
$$ . , . . . . . , . . . |

Click Here To Show Diagram Code

[go]$$Bc
$$ -----------------------+
$$ . . . . . . . . . . . |
$$ . . . . O X . . . . . |
$$ . . . O . X X X X . . |
$$ . O . . . O O O X . . |
$$ . . . . X . . . X . . |
$$ . . . . X . O . X . . |
$$ . . . X . O . . . . . |
$$ . . . . . . O . X . . |
$$ . O . O . O . X . . . |
$$ . , . . . . . , . . . |[/go]

What about this one? (I'd think this one would be "easier" because of the overly common use of the crane's nest as a teaching example of tesuji)

This one wasn't fair for me to measure, because I immediately knew the answer when you mentioned the crane's nest in the problem description.