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Ekisei Tsubiho 1 http://prod.lifein19x19.com/viewtopic.php?f=15&t=17374	Page 1 of 2

Author:	John Fairbairn [ Thu Apr 09, 2020 10:20 am ]
Post subject:	Ekisei Tsubiho 1
Attachment: Ekisei1.png [ 2.1 KiB \| Viewed 13160 times ] People at home will be a little jaded, I expect. I am. So I thought something tasty - different but not too heavy - might be a welcome change. The above is just a tsumego problem. What's different is simply the source. Very few people will have seen the Ekisei Tsubiho, a Japanese book published by some Buddhist priests in 1773. It was written by a Chinese, however, Chen Jiru. Chen apparently spent some time in Japan. His work in turn was based on the Ming-dynasty book Yi Zheng of 1583. That book's name is Ekisei in Japanese, and the Tsubiho portion indicates detailed help is being provided for the reader. There's actually not much of that help on show in the problems section. My main intent is simply to offer a problem that, I hope, because of the unusual source, is new to you, and one that is not too hard. But a secondary aim is to encourage readers to post not just solutions but also a brief note on the way they thought about it. The problem has the name "Nine stones turning into a dragon." If you are familiar with old Chinese names for problems, you'll realise there's a clue in there. But I'll leave the actual solution for another day. If this appeals (and some spark of life is shown on L19 ), I'll post some more from various classics.

Author:	Harleqin [ Thu Apr 09, 2020 2:36 pm ]
Post subject:	Re: Ekisei Tsubiho 1
First, I noted that it doesn't help White to get either the descent or the kosumi in sente. Then I briefly pondered how stable the outside really is, before returning to the double throw-in and adding another to get a promising damezumari, which doesn't even leave a killable shadow, and for which the outside liberties are more than enough.

Author:	jlt [ Thu Apr 09, 2020 2:42 pm ]
Post subject:	Re: Ekisei Tsubiho 1
Let's make a diagram Click Here To Show Diagram Code `[go]$$Wc $$ . . . . . . . . . . \| $$ . . . . . . . . . . \| $$ . . . . . . . . . . \| $$ . . . X . X . X . . \| $$ , . X . . . , . X . \| $$ . . X O O O O O O X \| $$ . . X O . X . O X . \| $$ . . X O X . . . . . \| $$ ---------------------[/go]` I don't see how White can live. If White O2 then Black P1. If White R1 then Black T2. If White T2 then T1 S1 R1 Q1 T2 and White has no move.

Author:	SoDesuNe [ Thu Apr 09, 2020 2:55 pm ]
Post subject:	Re: Ekisei Tsubiho 1
Thoughts: I confess I had to use a board and move stones around because all that sacrificing got me dizzy and made me misremember the shape. As a preliminary: "Nine stones turning into a dragon" does not really ring a bell for me. I would name the problem "Feed the tiger poisened food", because of creating all those tiger mouths through sacrificing. (Only true of course if my attempt is somewhat correct). My starting point was seeing that the shape/space does not grant two eyes to White. I was reminded of similar problems, where the key was to force the opponent into damezumari and so I tried to fill the dragon's cave with poisened food to lure in the tiger and swallow him whole in the end! Attempt (without peaking anywhere) Click Here To Show Diagram Code `[go]$$Wc Starting point (?) $$ . . . . . . . . . . . \| $$ . . . . . . . . . . . \| $$ . . . . . . . . . . . \| $$ . . . . . . . . . . . \| $$ . . . . X . X . X . . \| $$ . , . X . . . , . X . \| $$ . . . X O O O O O O X \| $$ . . . X O . X . O X 1 \| $$ . . . X O X 3 . . . 2 \| $$ ----------------------+[/go]` Click Here To Show Diagram Code `[go]$$Wcm3 Variation 1: 'a' and 'b' miai $$ . . . . . . . . . . . \| $$ . . . . . . . . . . . \| $$ . . . . . . . . . . . \| $$ . . . . . . . . . . . \| $$ . . . . X . X . X . . \| $$ . , . X . . . , . X . \| $$ . . . X O O O O O O X \| $$ . . . X O 2 X b O X . \| $$ . . . X O X 1 . 3 a X \| $$ ----------------------+[/go]` Click Here To Show Diagram Code `[go]$$Wcm3 Variation 2 $$ . . . . . . . . . . . \| $$ . . . . . . . . . . . \| $$ . . . . . . . . . . . \| $$ . . . . . . . . . . . \| $$ . . . . X . X . X . . \| $$ . , . X . . . , . X . \| $$ . . . X O O O O O O X \| $$ . . . X O . X . O X . \| $$ . . . X O X 1 2 4 3 X \| $$ ----------------------+[/go]` Click Here To Show Diagram Code `[go]$$Wcm7 Variation 2: at 'a' dies $$ . . . . . . . . . . . \| $$ . . . . . . . . . . . \| $$ . . . . . . . . . . . \| $$ . . . . . . . . . . . \| $$ . . . . X . X . X . . \| $$ . , . X . . . , . X . \| $$ . . . X O O O O O O X \| $$ . . . X O 1 X a O X . \| $$ . . . X O X . X X . X \| $$ ----------------------+[/go]` Click Here To Show Diagram Code `[go]$$Wcm7 Variation 2: at 'a' is the same $$ . . . . . . . . . . . \| $$ . . . . . . . . . . . \| $$ . . . . . . . . . . . \| $$ . . . . . . . . . . . \| $$ . . . . X . X . X . . \| $$ . , . X . . . , . X 2 \| $$ . . . X O O O O O O X \| $$ . . . X O 1 X 3 O X a \| $$ . . . X O X 4 X X 5 X \| $$ ----------------------+[/go]` Click Here To Show Diagram Code `[go]$$Bcm12 Variation 2: Alive $$ . . . . . . . . . . . \| $$ . . . . . . . . . . . \| $$ . . . . . . . . . . . \| $$ . . . . . . . . . . . \| $$ . . . . X . X . X . . \| $$ . , . X . . . , . X X \| $$ . . . X O O O O O O X \| $$ . . . X O O . . O X . \| $$ . . . X O . 2 . 1 . X \| $$ ----------------------+[/go]` Click Here To Show Diagram Code `[go]$$Wcm7 Variation 2: Ko $$ . . . . . . . . . . . \| $$ . . . . . . . . . . . \| $$ . . . . . . . . . . . \| $$ . . . . . . . . . . . \| $$ . . . . X . X . X . . \| $$ . , . X . . . , . X . \| $$ . . . X O O O O O O X \| $$ . . . X O 1 X 2 O X . \| $$ . . . X O X 3 X X . X \| $$ ----------------------+[/go]`

Author:	xela [ Thu Apr 09, 2020 5:44 pm ]
Post subject:	Re: Ekisei Tsubiho 1
John Fairbairn wrote: If this appeals (and some spark of life is shown on L19 ), I'll post some more from various classics. Yes, this appeals. I read out the same variations as SoDesuNe, after some struggle. So I guess this is a good level of difficulty for me (unless this isn't actually the solution, in which case -- too hard!)

Author:

John Fairbairn [ Fri Apr 10, 2020 2:23 am ]

Post subject:

Re: Problems from Ekisei Tsubiho and other classics

I don't need to post a solution as SoDesuNe has done an exemplary job. Better even than the original, which only gives moves up to 7. However, the original sees that as the special move, because 7 on the other side, at O2, as SDN points out, allows Black to kill (although it doesn't show the subsequent moves). This intricacy is the Tsubiho "assistant that goes into the intricacies" part of the book's name.

As to difficulty, there is a system used in Japan which grades problems as easy, intermediate, hard on the basis if whether it includes one, two or three themes. On the whole it seems to work very well, though normally, it seems as if that categorisation is meant to apply to problems that use the themes sequentially, but there are many problems that have, say, two themes=two steps but there is a third, or even a fourth in a variation line, which is also two steps.

There are also question marks over overlapping themes. For example, this problem could be said to have various themes, some in sequence, some in variations: throw-in, damezumari, ko, under-the-stones, connect-and-die. Personally I count it as a two-themer sequentially because damezumari is implied for either under-the-stones or connect-and-die. And not only is ko is in a variation line, it's a yose-ko. Maybe this problem was even the origin of the proverb that a yose-ko requiring two or more approach moves is no ko.

There is also the question of hints. Far from all old classics use names for problems, but many do, and I think for two reasons. One is as an aid to remembering: "Nine stones turning into a dragon" reminds you it has nine white stones in a sort of cloud shape. "Turning/changing into" usually has the Daoist connotation of immortality or coming back to life, as in under-the=stones. The dragon as a cloud suggests also swirling changes at the base of the cloud - black and white stones intermingling.

As to why hints and reminders are used, it is my conjecture - but one based on references in the many hundreds of Chinese poems that mention go - that gentlemen or priests would invite friends rounds for social mingling (remember that concept? - I find it hard) and, aided by wine and sweetmeats, would discuss an objet d'art: a vase, a piece of calligraphy, or even a poem, or better yet a tsumego problem. A name as enigmatic as a cryptic crossword clue would add to the elegance.

Ad these gentlemen would discuss the problem, as SDN and others did here, and thereby thoroughly learn something from their pals, especially about how to think about problems. In that vein, I will give another problem because it raises a perplexing issue that I would love to see discussed.

The following problem (White to play) is one of a fairly common type in the old classics. But it is a type I find extraordinarily hard. My question is: why?

The type I am referring to is a tightly enclosed corner group where the enclosed stones are spaced apart higgledy-piggedly. My reasons as to why the are hard start with the observation that these problems tend to look artificial and do not appear in real games. So I lack familiarity with these sorts of positions. A second reason must be that the openness means there are several possible starting points. More life-like problems can share a multiplicity of starting moves and they are generally classed as hard. But I think there is a deeper reason to be teased out, and I sense it's something to do with lack of a strategy for choosing a candidate move to explore first (maybe that's just my Reason 1 restated in a different way?).

This particular problem may actually be familiar to you as it appears in Gateway To All Marvels under the title ‘New cicada comes out of its shell’ (wherein, as above, lies a strong clue), but with the first few moves played out, and in the form as here i.e. with six black stones) but with the name ‘The Six Dings’ (Dings were Daoist gods, so you know Daoist immortality comes in). It actually appears also in the even older Carefree and Innocent Pastime where it has a graphic name, ‘Six fish-hawks flying backwards,’ referring to a historical event when a great storm literally put the wind up six naughty birds who were not practising social distancing.

But I chose this problem by looking at the Chinese classic Bequest of the Autumn Hermit, from the Ming dynasty. Author Zhu Keming presumably chose his autumnal sobriquet as an allusion to the go master mentioned disapprovingly by Mencius a thousand years earlier. Mencius was a Conficianist. Daoists often liked poking Confucianists in the eye and one way of doing that was by liking go. In his book the problem has the name 'Hard to fathom'. Which may be true enough, but raises another topic for discussion. Certain names can give strong hints, and then problem becomes easy (or easier). That surely raises the question of whether we should be teaching life & death by using hints more liberally, as a way of teaching solving strategies rather than expecting the solver to glare at a problem and trying to read out everything tactically.

So get out your wine and sweetmeats - or a pint and some pork scratchings if you prefer - think about this problem, then DISCUSS. This is L19, after all, a forum for gentlemen. It is not Reddit.

Attachments:

L19-AutumnHermit1.sgf [106 Bytes]
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Author:	SoDesuNe [ Fri Apr 10, 2020 8:13 am ]
Post subject:	Re: Ekisei Tsubiho 1
Click Here To Show Diagram Code `[go]$$Wc $$ \| . . . . . . . . $$ \| . . . . . . . . $$ \| . . . . . . . . $$ \| . O O O O . . . $$ \| . . X X . O . . $$ \| X . . , X O . . $$ \| . . . X . O . . $$ \| . X . O O . . . $$ \| . . . . . . . . $$ +-----------------[/go]` Thoughts and attempt: I also have difficulties with those "open border"/undefined eye-shape problems. I try to cope with this in two ways: First is starting not with vital points but with eye-space-reducing-moves and submissive replys (if they work I don't need to read complicated stuff). This is simple and can be calculated quite quickly. Second is following the proverb that your opponent's key point is your own. Disclaimer: I did need a board and stones again, to figure out all the intricacies. Though I have to say, I got to the first four moves on my own and saw a good chunk of the variations. Click Here To Show Diagram Code `[go]$$Wc Reducing Black's eye-space $$ \| . . . . . . . . $$ \| . . . . . . . . $$ \| . . . . . . . . $$ \| . O O O O . . . $$ \| . . X X . O . . $$ \| X . . , X O . . $$ \| . . . X . O . . $$ \| . X 1 O O . . . $$ \| . . . . . . . . $$ +-----------------[/go]` Click Here To Show Diagram Code `[go]$$Wc Variation 1: Tearing through $$ \| . . . . . . . . $$ \| . . . . . . . . $$ \| . . . . . . . . $$ \| . O O O O . . . $$ \| . . X X . O . . $$ \| X . . , X O . . $$ \| . . 3 X . O . . $$ \| . X 1 O O . . . $$ \| . 2 . . . . . . $$ +-----------------[/go]` Click Here To Show Diagram Code `[go]$$Wc Variation 2: Helping Black build a nice nest $$ \| . . . . . . . . $$ \| . . . . . . . . $$ \| . . . . . . . . $$ \| . O O O O . . . $$ \| . 5 X X . O . . $$ \| X 6 . , X O . . $$ \| . . 2 X . O . . $$ \| 4 X 1 O O . . . $$ \| . 3 . . . . . . $$ +-----------------[/go]` Now you can start going backward. Try at for example. It still lives (insert effortful practice ; )), so you have to go back even further. Click Here To Show Diagram Code `[go]$$Wc Variation 3: where are Black's eyes? $$ \| . . . . . . . . $$ \| . . . . . . . . $$ \| . . . . . . . . $$ \| . O O O O . . . $$ \| . . X X . O . . $$ \| X . d a X O . . $$ \| b c 2 X . O . . $$ \| . X 1 O O . . . $$ \| . . . . . . . . $$ +-----------------[/go]` It's time to go deeper now. Recognise the eye-shape, see familair patterns. After the exchange for , it is "easy" to see that 'a' is already an eye. The second eye will most likely be around 'b'. Do you have any moves to take away the second eye? I reckon you will end up in situations where 'c' and 'd' become miai and so Black lives. With all that out of the way: What did we learn? 1) We have an idea, where Black's eyes will be. 2) When Black responds at he's already alive. So seems to be a key point in Black's shape. According to proverb this key point could also work in White's favour! Click Here To Show Diagram Code `[go]$$Wc Variation 4: Cutting the eye! $$ \| . . . . . . . . $$ \| . . . . . . . . $$ \| . . . . . . . . $$ \| . O O O O . . . $$ \| . . X X . O . . $$ \| X . . . X O . . $$ \| . . 1 X . O . . $$ \| . X . O O . . . $$ \| . . . . . . . . $$ +-----------------[/go]` Click Here To Show Diagram Code `[go]$$Wc Variation 4: tearing through the 2nd $$ \| . . . . . . . . $$ \| . . . . . . . . $$ \| . . . . . . . . $$ \| . O O O O . . . $$ \| . . X X . O . . $$ \| X . . . X O . . $$ \| . 2 1 X . O . . $$ \| . X 3 O O . . . $$ \| . . . . . . . . $$ +-----------------[/go]` Click Here To Show Diagram Code `[go]$$Wc Variation 5: Entering the belly of the beast $$ \| . . . . . . . . $$ \| . . . . . . . . $$ \| . . . . . . . . $$ \| . O O O O . . . $$ \| . . X X b O . . $$ \| X . . . X O . . $$ \| . . 1 X a O . . $$ \| . X 2 O O . . . $$ \| . . . . . . . . $$ +-----------------[/go]` This gets more complex but can also be made a little bit rational. White should not be so fast and play atari at 'a'. Black will sacrifice this stone and live - please confirm : ) Furthermore when Black cannot capture White with his next move, the atari can be played later as well. If Black plays 'a', White can force 'b' with the same result. Click Here To Show Diagram Code `[go]$$Wc Variation 5 $$ \| . . . . . . . . $$ \| . . . . . . . . $$ \| . . . . . . . . $$ \| . O O O O . . . $$ \| . . X X . O . . $$ \| X . . . X O . . $$ \| . 3 1 X . O . . $$ \| . X 2 O O . . . $$ \| . . . . . . . . $$ +-----------------[/go]` So, when you have confirmed that is Black's key point to live when White decides to atari right away, why not play there yourself? Click Here To Show Diagram Code `[go]$$Bcm4 Variation 5: No ko! $$ \| . . . . . . . . $$ \| . . . . . . . . $$ \| . . . . . . . . $$ \| . O O O O . . . $$ \| . . X X 4 O . . $$ \| X . 3 . X O . . $$ \| . O O X 2 O . . $$ \| 1 X X O O . . . $$ \| . . . . . . . . $$ +-----------------[/go]` Click Here To Show Diagram Code `[go]$$Bcm4 Variation 6: Black collapses due to liberty shortage $$ \| . . . . . . . . $$ \| . . . . . . . . $$ \| . . . . . . . . $$ \| . O O O O . . . $$ \| . . X X . O . . $$ \| X 8 . 3 X O . . $$ \| 6 O O X 2 O . . $$ \| 1 X X O O . . . $$ \| . 5 4 7 . . . . $$ +-----------------[/go]` Click Here To Show Diagram Code `[go]$$Bcm4 Variation 7: Ko $$ \| . . . . . . . . $$ \| . . . . . . . . $$ \| . . . . . . . . $$ \| . O O O O . . . $$ \| . . X X . O . . $$ \| X . 3 4 X O . . $$ \| 1 O O X 2 O . . $$ \| . X X O O . . . $$ \| . . . . . . . . $$ +-----------------[/go]` Click Here To Show Diagram Code `[go]$$Bcm4 Variation 8: If Black refuses the ko... $$ \| . . . . . . . . $$ \| . . . . . . . . $$ \| . . . . . . . . $$ \| . O O O O . . . $$ \| . . X X . O . . $$ \| X 8 . 3 X O . . $$ \| 1 O O X 2 O . . $$ \| 6 X X O O . . . $$ \| . 5 4 7 . . . . $$ +-----------------[/go]` But did you remember the proverb? Your opponent's key-point is your own? Click Here To Show Diagram Code `[go]$$Bcm4 Variation 9: Guzumi! $$ \| . . . . . . . . $$ \| . . . . . . . . $$ \| . . . . . . . . $$ \| . O O O O . . . $$ \| . . X X . O . . $$ \| X . . . X O . . $$ \| . O O X . O . . $$ \| . X X O O . . . $$ \| . . 1 . . . . . $$ +-----------------[/go]` Click Here To Show Diagram Code `[go]$$Bcm4 Variation 9: Or not... $$ \| . . . . . . . . $$ \| . . . . . . . . $$ \| . . . . . . . . $$ \| . O O O O . . . $$ \| . . X X . O . . $$ \| X 4 . . X O . . $$ \| 3 O O X . O . . $$ \| 2 X X O O . . . $$ \| . . 1 . . . . . $$ +-----------------[/go]` So, I guess it's ko? To be fair, this ko is better for Black: Click Here To Show Diagram Code `[go]$$Bcm4 Variation 10: Ko² $$ \| . . . . . . . . $$ \| . . . . . . . . $$ \| . . . . . . . . $$ \| . O O O O . . . $$ \| . . X X . O . . $$ \| X . 1 3 X O . . $$ \| . O O X 2 O . . $$ \| 6 X X O O . . . $$ \| 7 4 5 . . . . . $$ +-----------------[/go]` (I'm really tired now, so the possibilitiy is high that I missed something ^^) TL;DR Start with reducing the eye-space. Play the move, which refuted your last play.

Author:	Shaddy [ Fri Apr 10, 2020 9:34 am ]
Post subject:	Re: Ekisei Tsubiho 1
Click Here To Show Diagram Code `[go]$$Bcm4 Variation 9: Guzumi! $$ \| . . . . . . . . $$ \| . . . . . . . . $$ \| . . . . . . . . $$ \| . O O O O . . . $$ \| . . X X . O . . $$ \| X 1 3 . X O . . $$ \| 5 O 6 X 4 O . . $$ \| . X X O O . . . $$ \| . 2 7 . . . . . $$ +-----------------[/go]` This is one of the problems from XXQJ (well.. from somewhere, and it appears there; it's also in the LCH tsumego series, I think) which has a pretty solution but is actually a ko. It's just not your ko :p Problems with a bunch of stones scattered into an enclosed corner also give me fits. I think it's because I can't guess what the tesuji will be, which means I have to prune branches manually instead of skipping steps. This problem is tame for one of those; there are only two or three reasonable first moves, and their followups are relatively branchless.

Author:	Bill Spight [ Fri Apr 10, 2020 10:29 am ]
Post subject:	Re: Ekisei Tsubiho 1
I also find these problems difficult. Click Here To Show Diagram Code `[go]$$Wc $$ \| . . . . . . . . $$ \| . . . . . . . . $$ \| . . . . . . . . $$ \| . O O O O . . . $$ \| . . X X . O . . $$ \| X . . , X O . . $$ \| . . . X . O . . $$ \| . X . O O . . . $$ \| . . . . . . . . $$ +-----------------[/go]` FWIW: I draw some fake boundaries based upon proximity. Click Here To Show Diagram Code `[go]$$Wc $$ \| . . . . . . . . $$ \| . . . . . . . . $$ \| . . . . . . . . $$ \| . O O O O . . . $$ \| . . X X . O . . $$ \| X B . , X O . . $$ \| . . B X . O . . $$ \| . X . O O . . . $$ \| . B . . . . . . $$ +-----------------[/go]` In this case doing so produces two eyes. So it looks like the first question is not to find the vital point inside an eye, but to try to prevent the formation of two eyes. Click Here To Show Diagram Code `[go]$$Wc $$ \| . . . . . . . . $$ \| . . . . . . . . $$ \| . . . . . . . . $$ \| . O O O O . . . $$ \| . . X X . O . . $$ \| X a C S X O . . $$ \| . C 1 X . O . . $$ \| . X . O O . . . $$ \| . . . . . . . . $$ +-----------------[/go]` looks promising. Both it and a prevent the points from becoming eye points, at least initially, but because of damezumari also prevents from becoming an eye point, at least initially. FWIW, those are my initial thoughts, before doing any reading.

Author:	RobertJasiek [ Fri Apr 10, 2020 10:45 am ]
Post subject:	Re: Ekisei Tsubiho 1
On average, real game problems differ from invented problems. The latter more often allow application of techniques / themes, solving strategies or finding the first move being the major effort. During the last half of a year, I have studied hundreds of real game problems involving tactical reading and found that solving of only 11% is accelerated by techniques, solving strategies and the like. (There are a few other aspects occurring due to a restricted study purpose.) By far most real game problems must be solved by disciplined tactical reading of all mandatory variations and decisions. Only methods of tactical reading itself may decrease the numbers of mandatory variations, such as creation of a position with a known result not requiring reading beyond it or verifying at least one next move with the optimal result. Instead of reading all variations, this can mean to read "only" all mandatory variations. Therefore, number of themes or first moves are very weak measures of difficulty. Much more relevant is the minimum number of variations whose reading is mandatory (because they cannot be pruned) together with their numbers of moves and necessary decisions among the variations to be related. Compromise results are difficult because they can require reading "all" alternatives to possibly find a better result and consideration of finer details, such as comparing different types of kos, excess numbers of local ko threats, capture-first and other aspects up to optimising endgame counts (the latter in 4% of ordinary real game tactical problems with a middle game flair).

Author:	xela [ Sat Apr 11, 2020 5:16 am ]
Post subject:	Re: Ekisei Tsubiho 1
It's no good, John, the name "Ekisei Tsubiho" is just too hard to remember. The first word keeps reminding me of another fighting technique I heard about many years ago, and I'm getting them mixed up. From now on, I think I'll call them the Ecky-Thump Tsumego.

Author:	John Fairbairn [ Mon Apr 13, 2020 12:17 am ]
Post subject:	Re: Ekisei Tsubiho 1
Here is the solution to the second probem as given by Ecky Thump. It's evidently pointless trying to get a discussion going on L19 nowadays. I've tried quote a few times and am now giving up totally. I will only post here to make announcements, or maybe answer the odd question. I will become a selfish lurker - although there's nothing to lurk about.... For non-Brits, Ecky Thump was mainly a Lancashire martial art introduced by the Goodies. It just so happened that the only good Goodie, Tim Brooke-Taylor, became a covid victim yesterday.

Author:	jlt [ Mon Apr 13, 2020 2:04 am ]
Post subject:	Re: Ekisei Tsubiho 1
The problems are too difficult for me, I don't even understand the official solution to this ~~tsubiho~~ tsumego. If is at A3, is the black group alive by ko or can White still kill unconditionally?

Author:	SoDesuNe [ Mon Apr 13, 2020 2:26 am ]
Post subject:	Re: Ekisei Tsubiho 1
That's a beautiful sequence. Although I did "read" the clamp I would have never guessed this order of moves afterwards. Thanks for showing and a real pity losing you as a regular contributor... @jlt Seems ko, yes. But I guess White has local threats so this is really hard for Black.

Author:	Tryss [ Mon Apr 13, 2020 6:19 am ]
Post subject:	Re: Ekisei Tsubiho 1
John Fairbairn wrote: It's evidently pointless trying to get a discussion going on L19 nowadays. I've tried quote a few times and am now giving up totally. I will only post here to make announcements, or maybe answer the odd question. I will become a selfish lurker - although there's nothing to lurk about.... What kind of discussion would you expect in this case?

Author:	Bill Spight [ Mon Apr 13, 2020 8:44 am ]
Post subject:	Re: Ekisei Tsubiho 1
Click Here To Show Diagram Code `[go]$$Wc $$ \| . . . . . . . . $$ \| . . . . . . . . $$ \| . . . . . . . . $$ \| . O O O O . . . $$ \| 4 2 X X . O . . $$ \| X 1 . , X O . . $$ \| 3 5 . X . O . . $$ \| . X . O O . . . $$ \| . . . . . . . . $$ +-----------------[/go]` If you start reading this way, you might be able to visualize the under the stones position.

Author:	Splatted [ Mon Apr 13, 2020 4:03 pm ]
Post subject:	Re: Ekisei Tsubiho 1
A little late, but my process for the first one: My first instinct is to check if white can make eyes with the space available. It seems black has to ignore two moves in a row: Click Here To Show Diagram Code `[go]$$Wc $$ . . . . . . . . . . \| $$ . . . . 4 2 . . . . \| $$ . . . . . . . . . . \| $$ . . . X . X . X . . \| $$ , . X . . . , . X . \| $$ . . X O O O O O O X \| $$ . . X O 5 X x O X a \| $$ . . X O X 3 1 y . b \| $$ ---------------------[/go]` Changing the order or playing "x" or "y" doesn't help. There's a possibility of getting the first move by playing "a" first and threatening a ko with 1 after black tackes at "b", but it's not enough. Still I wonder if there might be more to exploit there. I try reading things like this: Click Here To Show Diagram Code `[go]$$Wc $$ . . . . . . . . . . \| $$ . . . . . . . . . . \| $$ . . . . . . . . . . \| $$ . . . X . X c X b . \| $$ , . X . . . , 1 X . \| $$ . . X O O O O O O X \| $$ . . X O . X . O X a \| $$ . . X O X . x y z . \| $$ ---------------------[/go]` Threatening a cut at "b" in the hopes of somehow extending the tesuji at "a" or breaking out with "c". I'm guessing dragon in the old Chinese naming for convention for problems is not related to the meaning of a long thin group extending in to the centre, but I can't help but think of that when I hear dragon. Since none of that pans out I go back to looking at "x","y", and "z" in the hopes that I can find something to threaten on the left while also threatening "a". That's when I see it! The throw-in can be used on both sides! I think I've got it now, but just to be sure I'll read it out... Click Here To Show Diagram Code `[go]$$Wc Black 6 at 1 $$ . . . . . . . . . . \| $$ . . . . . . . . . . \| $$ . . . . . . . . . . \| $$ . . . X . X . X . . \| $$ , . X . . . , . X . \| $$ . . X O O O O O O X \| $$ . . X O . X . O X 1 \| $$ . . X O X 3 4 5 . 2 \| $$ ---------------------[/go]` ... and it doesn't work. For some reason I thought black wouldn't have enough liberties to fill in at 3. I'm tempted to give up and look at the answer here but since I'm tired I think I'll sleep on it and look again with fresh eyes. The solution is... er... to be announced at a later date.

Author:	Elom [ Wed Apr 15, 2020 12:20 pm ]
Post subject:	Re: Ekisei Tsubiho 1
I'm still a bit behind on the First one, although I do get the feeling that capturing-stones-captured stones puzzles . It's interesting that this particular tsumego from china was a tsuhibo. Given that hints are often given Chinese names I wonder if assisted puzzles were more common in China than Japan during that time period (and maybe Japan later adopted it more?)

Author:	Splatted [ Wed Apr 15, 2020 1:04 pm ]
Post subject:	Re: Ekisei Tsubiho 1
Second attempt at the first problem. I think I've got it! Process: Second attempt after my previous failed one. I intended to start by checking the sequences I read before for mistakes, but I couldn't help thinking what if I threw in twice on the bottom right? Could I catch white before he connects everything up...? Click Here To Show Diagram Code `[go]$$Wc $$ . . . . . . . . . . \| $$ . . . . . . . . . . \| $$ . . . . . . . . . . \| $$ . . . X . X . X . . \| $$ , . X . . . , . X 6 \| $$ . . X O O O O O O X \| $$ . . X O . X . O X 1 \| $$ . . X O X . 5 4 3 2 \| $$ ---------------------[/go]` Alas I can only hope for the worthless before the rest connects. Still this is worth exploring more. What if I also throw in on the left and force black to loosely connect his groups? Click Here To Show Diagram Code `[go]$$Wc $$ . . . . . . . . . . \| $$ . . . . . . . . . . \| $$ . . . . . . . . . . \| $$ . . . X . X . X . . \| $$ , . X . . . , . X . \| $$ . . X O O O O O O X \| $$ . . X O . X . O X 1 \| $$ . . X O X 5 6 4 3 2 \| $$ ---------------------[/go]` Click Here To Show Diagram Code `[go]$$Wc $$ . . . . . . . . . . \| $$ . . . . . . . . . . \| $$ . . . . . . . . . . \| $$ . . . X . X . X . . \| $$ , . X . . . , . X a \| $$ . . X O O O O O O X \| $$ . . X O 1 X 3 O X 4 \| $$ . . X O X 2 X X 5 X \| $$ ---------------------[/go]` And I was going to say this would allow me to catch some stones, but it's a dead shape. However while making the diagram I realised that black has to respond to 5 at "a", so white can live as below. Click Here To Show Diagram Code `[go]$$Wc $$ . . . . . . . . . . \| $$ . . . . . . . . . . \| $$ . . . . . . . . . . \| $$ . . . X . X . X . . \| $$ , . X . . . , . X 2 \| $$ . . X O O O O O O X \| $$ . . X O W . W O X X \| $$ . . X O . 3 . . 1 X \| $$ ---------------------[/go]` I think it might now just be a case of checking variations and ensuring all moves are optimal. I've already noticed that black should play before T2 and can take instead of connecting, but I don't think anything will change the result. I'm mainly trying to decide if the order of the two marked white stones matters and double checking all of blacks moves really are forcing moves. This is my final process diagram. [hide] Click Here To Show Diagram Code `[go]$$Wc $$ . . . . . . . . . . \| $$ . . . . . . . . . . \| $$ . . . . . . . . . . \| $$ . . . X . X . X . . \| $$ , . X . . . , . X 6 \| $$ . . X O O O O O O X \| $$ . . X O 7 X a O X 1 \| $$ . . X O X 5 b 4 3 2 \| $$ ---------------------[/go]` I thought there was potential for a ko if black ignored 5 and white played at 7 instead of "a", but I was still seeing a black stone at "b" and of course there wouldn't be if he didn't capture. I think my sequence is as good as it's going to get now, so time to post my solution! Solution: Click Here To Show Diagram Code `[go]$$Wc $$ . . . . . . . . . . \| $$ . . . . . . . . . . \| $$ . . . . . . . . . . \| $$ . . . X . X . X . . \| $$ , . X . . . , . X . \| $$ . . X O O O O O O X \| $$ . . X O 7 X a O X 1 \| $$ . . X O X 5 6 4 3 2 \| $$ ---------------------[/go]` I chose over "a" because white then has the option of capturing a stone immediately and gaining a liberty if it becomes necessary later. Click Here To Show Diagram Code `[go]$$Bcm8 $$ . . . . . . . . . . \| $$ . . . . . . . . . . \| $$ . . . . . . . . . . \| $$ . . . X . X . X . . \| $$ , . X . . . , . X 3 \| $$ . . X O O O O O O X \| $$ . . X O O X 2 O X . \| $$ . . X O X 1 X X 4 X \| $$ ---------------------[/go]` Click Here To Show Diagram Code `[go]$$Bcm12 $$ . . . . . . . . . . \| $$ . . . . . . . . . . \| $$ . . . . . . . . . . \| $$ . . . X . X . X . . \| $$ , . X . . . , . X X \| $$ . . X O O O O O O X \| $$ . . X O O . O O X . \| $$ . . X O . 2 . 1 . X \| $$ ---------------------[/go]` And there we have it. I'm a little dissappointed that I saw it while writing a diagram instead of relying purely on my reading, but I guess it's not a big deal. Now I can finally check my answer! That really was a fun problem... but I don't think I'll move on to the next one immediately. Edit: It seems I missed some important lines but I at least got the gist, which is a big improvement from the other day. I'm still reasonably content. Edit 2: Haha since John described it as "not too hard" I assumed everyone who had posted hide tags had solved it quickly and easily in their heads. I would have given up sooner if I new dan players found it difficult!

Author:	Elom [ Sun Apr 19, 2020 4:34 pm ]
Post subject:	Re: Ekisei Tsubiho 1
My thinking so far--thank you for the diagram jlt! My First written foray will focus on the many captures black can make . . . Click Here To Show Diagram Code `[go]$$Wc $$ . . . . . . . . . . \| $$ . . . . . . . . . . \| $$ . . . . . . . . . . \| $$ . . . X . X . X . . \| $$ , . X . . . , . X . \| $$ . . X O O O O O O X \| $$ . . X O . X 7 O X 1 \| $$ . . X O X 5 6 4 3 2 \| $$ ---------------------[/go]` This is what I foresee if black plays the 'non-thinking' response. Unless I'm badly mistaken, it doesn't seem that there's a way to stop white from gaining two eyes, so black maybe has a way to not make it so easy for white after 1.

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