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Playing a game backward
Path: CommentedGames   · Prev:   · Next: NewYearSRengo2002
  Difficulty: Beginner   Keywords: EndGame

Important notice: if you're a beginner reading this page and don't understand something, ask please. Just edit the page. You will be answered.

I have a strange idea. Maybe that comes under the influence of the movie Memento. It is rather an interesting story about a guy who had a peculiar condition. After an accident he could not convert short term memory into long term memory, so he forgot everything in about 10 minutes, though he remembered well everything before the accident. The movie is shown backwards in time, so the spectator does not remember what happened before too just as the main character.

The idea is intended for genuine beginners. I know that quite often beginners have no idea what to do with the next move. Partly, this is because they have no idea about the long term consequences of their moves while they understand that there are some. I propose to show them a game from the end.

First, we start from the final position and explain why there is no value to the moves, explain that putting a stone in opponent's territory forcing a reply has zero value and is considered bad manners, while putting a dead stone is a loss of a point. We explain also what groups on the board are dead and then remove them, and score the game. The next step would be to rewind it ten moves back when there are some values to the moves yet and show how the late yose is played, i.e. how the opponents territory is reduced by making threats. Sente and gote come naturally.

Then rewind it back ten moves more and continue rewinding it until we come to a fight. We can show importance of the stones positioned earlier and analyse the fight. Slowly we will end up in the fuseki.

I have a game that is suitable. It was a fast game on IGS and it is full of stupid mistakes at all stages, so there could be a lot of comments and problems. There are dead groups in the final position (but no seki), there was a ko-fight in the middle of the game, the score is close, there is a lot of life and death, so it is fun. However, as almost always in my games, it was my opponent who made most of the mistakes in the chuban and my fuseki was just awful, so White was behind all the time but managed to win by 0.5 point.

I want some feedback on the idea. What would the senseis say? Is it worthwhile? I understand that the feedback from the genuine beginners is impossible for obvious reasons. But could that kind of read be interesting for them?

[Diagram]
Final position

Komi is 5.5.

White captured 10 black stones.

Black captured 8 white stones.

Result: White won by 0.5 points.



First, we have to read the position correctly and determine which stones on the board are dead. Usually the players have to agree on each of the groups. Usually this proceeds smoothly, disputes are rare. The next diagram shows dead stones, as BC and WC. In the real-life game they are removed from the board and added to the prisoners.

[Diagram]
Dead stones are marked


Below, the scoring procedure will be explained. If you know how to score the game, skip to PGB Why There Is No Useful Move Left


Next step is to fill the neutral points. With [Japanese scoring] it does not matter if you fill them with white or black stones. With Chinese scoring this may change the result, so filling neutral points is a part of the game and is done alternately with white and black stones.

[Diagram]
Filling neutral points

In this position White (it's her turn now) fills the only neutral point.



So, the next step is to remove the dead stones, which produces the following:

[Diagram]
Dead stones are removed

Komi 5.5

White has 10+19=29 prisoners

Black has 8+ 24=32 prisoners



Next step during counting is to put the prisoners on the board filling the territory of your opponent.

At this moment White has 34 stones in the lid of her bowl (this includes 5 komi stones given to her by Black before the game). Black's lid contains 32 stones.

Let's see what is the result of the operation.

[Diagram]
Dead stones are returned to the board


The next operation is to move the stones in the territories to form nice rectangles. On a real board it is easy.

It does not matter if the boundary is not of the proper color as long as you remember whose territory this is.

[Diagram]
Arranging the stones

White has 2x4+2x3+3x6+1 = 6+8+18+1 = 33 moku

Black has 4x8+1 = 33 moku

Since komi is 5.5 points and not 5 points this means that White won by half a point.



This method to count the score is used in Ukraine.

In Singapore it is done differently. The procedure is the following.

  • Neutral points are filled.
  • Black fills his territory with black stones taking them from the bowl.
  • All black stones are returned into the empty bowl.
  • If they don't fill the bowl then White won.
  • If they fill the bowl and there are some left then Black won.

They say the result is almost always the same. Sometimes it differs by a point. This issue is discussed hotly. Refer to the counting pages if you want to know why. The rules in different countries vary a little and all you want to know is what rule set is applied. Most of us don't care too much.

The next page, PGB Why There Is No Useful Move Left, takes you one step backward to the point when both opponents passed. This is very important moment of the game. The game should be finished before scoring.


Index

  • PGB Why There Is No Useful Move Left
  • PGB281 - backtracking to move 281
  • PGB271 - backtracking to move 271
  • PGB261 - backtracking to move 261
  • PGB251 - backtracking to move 251
  • PGB241 - backtracking to move 241
  • PGB231 - backtracking to move 231
  • PGB221 - backtracking to move 221
  • PGB211 - backtracking to move 211
  • PGB201 - backtracking to move 201
  • PGB191 - backtracking to move 191
  • PGB181 - backtracking to move 181
  • PGB171 - backtracking to move 171
  • PGB161 - backtracking to move 161
  • PGB151 - backtracking to move 151
  • PGB141 - backtracking to move 141
  • PGB131 - backtracking to move 131
  • PGB121 - backtracking to move 121
  • PGB111 - backtracking to move 111
  • PGB101 - backtracking to move 101
  • PGB91 - backtracking to move 91
  • PGB81 - backtracking to move 81
  • PGB71 - backtracking to move 71
  • PGB61 - backtracking to move 61
  • PGB51 - backtracking to move 51
  • PGB41 - backtracking to move 41
  • PGB31 - backtracking to move 31
  • PGB21 - backtracking to move 21
  • PGB11 - backtracking to move 11
  • PGB1 - backtracking to move 1

I've been following this game played backwards, and I don't really see the interest (however interesting your idea may be). In particular I would rather try to give meaning to "take away the last move" rather than take away the last ten and then play them back in forward mode as you're doing now. --DieterVerhofstadt

HolIgor: The idea was like to show the game chunk by chunk. First, what the final position is, and why it is final; then the position in which several useful moves were left, then the rest of the yose, middle game and fuseki at last.

It does not work move by move because there is no interest in guessing what the last move was. And I mean it for the beginners and not for you. I suspected the yose will take a little bit too long, it is always long. But at the same time if I mean it for the beginners I have to show some tricks and possible mistakes in the endgame. There are a lot of mistakes in the game itself. I've chosen a very poor game to be able to show better moves in many places.

Never mind, if it does not work then let it be.

--DieterVerhofstadt Oh, no, please continue.

HolIgor: I did not mean that I wanted to stop. I rather meant that if it is not useful that it does no harm :)

I think this is a great idea, HolIgor! :-) One request: could you make the game record SGF file available on this page? Thanks. --BillSpight

I like this idea. As someone who is very new to go, it is difficult for me to see what the real objective and how to wind things down. Starting backwards shows that. The moves at the beginning don't make any sense until you understand where it is you are trying to get to. Thanks for your efforts, --XScott

kokiri I'm interested in comparing where the territory is at the end of the game with what shapes and extensions the two players make through the game. I think that this sort of backwards approach might give an insight into which parts of the board really are big and which ones look big early on, but actually aren't.



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(OC) 2003 the Authors, published under the OpenContent License V1.0.