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Beginner-Question on professional game
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Author:  Tomoe [ Sat Apr 25, 2015 4:20 pm ]
Post subject:  Beginner-Question on professional game
Hello everyone,

I just replayed the following game played by Honinbo Shusaku and Ota Yuzo.



I just can't figure out why white resigned. It's 1 am here and I'm quite tired, so please excuse if I overlooked something really obvious... White seems to have much territory on right and the lower left. Even if he's behind, to me it doesn't seem to be so much that he had to resign.

Could someone maybe tell me what I'm missing here? :)

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Author:  Mike Novack [ Sat Apr 25, 2015 5:56 pm ]
Post subject:  Re: Beginner-Question on professional game
Tomoe wrote:
Even if he's behind, to me it doesn't seem to be so much that he had to resign.
Could someone maybe tell me what I'm missing here? :)


Without addressing the game itself I can tell you something you are missing by what you just said. At the level of players involved, what do you imagine would constitute "hopelessly behind"? Might I suggest that difference is smaller than the uncertainty of your count (you said "even if")
Author:  Tomoe [ Sat Apr 25, 2015 6:44 pm ]
Post subject:  Re: Beginner-Question on professional game
I actually didn't try to count accurately (as you said I probably wouldn't have been able to do so anyways), once I didn't expect that someone would surrender at this point if he's "only a few points" behind. Until now it was my understanding that one only surrenders after <150 moves if a group of yours died or you’re already behind by just roughly comparing territories.
But okay, I see, if there is nowhere to fight anymore and there is a small but clear lead, it might not make any sense to continue at this level. Thanks!
Author:  Charles Matthews [ Sun Apr 26, 2015 6:21 am ]
Post subject:  Re: Beginner-Question on professional game
Tomoe wrote:
But okay, I see, if there is nowhere to fight anymore and there is a small but clear lead, it might not make any sense to continue at this level. Thanks!


It is not that easy to count the game, though it seems clear to me that Black is ahead.

White tried a ploy, letting the two stones on the left side get cut off, and reaching out towards them instead (a 5 dan once told me that this was an aspect of pro style). Black captured the stones: White tried to mine the upper left corner for whatever potential was there.

First question, though: what's a big lead? I decided some time ago that eight points was big. I think Black has this kind of lead, but it depends on what is going on in the centre, and some reading is needed there.

White is not connected through from the upper centre to the right side. If that is the case, White has to make eyes with the big upper group. That means a sequence of gote moves to defend eye space, ending up with a small number of points (fingers of one hand).

Black however can profit elsewhere, in the lower centre, where some white stones can get cut off. This adds up to saying "all the upside is Black's" from here on in.

Technically, there could be a ko in the top left. Reading a ko right out, just to count the game, is hard work, clearly. This is why we have the "picnic ko" concept, really: as long as Black doesn't risk too much, while White stakes the central group, the ko is also on the upside for Black. Black may not have to seek a "best result" for the ko, just a simplifying result. Overall thickness comes into play here.

I don't know how satisfactory you will find this. Three big steps: (a) count the game if nothing serious now dies; (b) read out the upper group status and endgame; (c) dispose of the ko business. One smallish one: what does Black have in the lower centre?

My guess is that both players had sussed this all out, roughly at least, about 30 plays before the end. White grabbed territory on the left side, probably knowing that with best play it would come to this.

Bottom line: a pro resignation is timed to show something.
Author:  Uberdude [ Sun Apr 26, 2015 7:11 am ]
Post subject:  Re: Beginner-Question on professional game
Further to what Charles said, my understanding for why white resigned at this particular moment is because of black's choice of playing e16 and fighting a ko, rather than the more passive connection at c17. By doing that black is declaring he has analysed the ko threats and declares that he has enough to win the ko (or pick up adequate compensation elsewhere). White could continue to contest that declaration by continuing play but given they both have plenty of time to think he decided not to. In that respect the d16 was a bit of a bluff to see if black would be a chicken, and when black called the bluff white resigned.
Author:  Bill Spight [ Sun Apr 26, 2015 7:55 am ]
Post subject:  Re: Beginner-Question on professional game
Let me second what has already been said. Charles has provided a verbal analysis, which I can support with a couple of variations. :) Go to move 139.



With no time limits, top players in the 19th century could play nearly flawless endgames. With the time limits of today, I don't know if White would resign. Surely Ota had assessed the game and read far enough ahead to see no chance of winning against his formidable opponent. My guess is that Black had a win of around 10 points, maybe 8 points, as Charles suggests.
Author:  gowan [ Sun Apr 26, 2015 12:43 pm ]
Post subject:  Re: Beginner-Question on professional game
In many old games the game record does not include all the moves played at the end of the game. Any possibility that that could be the case for this game?

In the book Invincible this game has comments by Go Seigen! The only comments about the end of the game are: White 104 is the losing move (should have been at w108), WHite tries to get back in the game with White 112, but Black answers cautiously and solidly.
Author:  Bki [ Sun Apr 26, 2015 6:02 pm ]
Post subject:  Re: Beginner-Question on professional game
gowan wrote:
In many old games the game record does not include all the moves played at the end of the game. Any possibility that that could be the case for this game?

In the book Invincible this game has comments by Go Seigen! The only comments about the end of the game are: White 104 is the losing move (should have been at w108), WHite tries to get back in the game with White 112, but Black answers cautiously and solidly.


But it is also pointed out whether the loser resigned or lost by x points. In this case, it is clearly said "White resigns after Black 139"

Invincible also points out when there are move beyond forced endgames plays and dame-filling left when the record ended.
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