© Copyright 2016 by Thomas Redecker

Workbook: One-Move Life and Death Problems

Basic Tsume-Go Strategy Made Easy

Thomas Redecker

Buy the full book at gobooks.com

This workbook is designed especially for beginners — each of the about 1,100 problems only requires you to think ahead a single move.

The problems of this collection are ordered by shape. Repetition matters, so each shape provides as many slightly different problems as possible. While each problem is explained in detail, readers can choose whether to simply continue with the next problem, or switch to the detailed explanation of the main solution, side variations, failures and the analysis of the problem’s shape issues.

Usually, side variations and refutations of failures are more complicated than the main path of the problem’s solution. While studying these additional variations — again at the reader’s own choice — the reader will be gently and subtly guided to more complicated issues in the beautiful field of tsume-go, preparing for the next step in study.

This ePub reader does not support full scripting, so diagrams may not be interactive.

Copyright Page

Second edition.

© 2017, Thomas Redecker, Berlin. All rights reserved.

This book or any portion thereof may not be reproduced or used in any manner whatsoever without the express written permission of the publisher except for the use of brief quotations in a book review or scholarly journal.

Email: igohatsuyoron120@gmail.com

Introduction

Foreword to the second edition

During my work on “three-move tsume-go” I found a large number of one-move problems – especially for five- and six-point eye shapes – which were not yet included in this book, but are incorporated now.

Additionally, the book has been restructured and rephrased a bit and has been thoroughly checked and revised.

This second edition has been restricted to eye shapes up to six points. On the one hand, suitable seven-point eye shape problems are very rare; on the other hand I still have no idea how to categorize these.

Owners of the first edition will find that the numbers of the “old” problems have been maintained. The “new” problems start with number 1001.

In order to collocate all the side explanations that had been scattered throughout the entire book before, I created a new chapter “Conventions and Concepts”. Please note that there will be almost no need to read this chapter in the very beginning. You might want to refer to it in case an appropriate question arises in the later course of your study.

Do not “read” this book!

This workbook must not be understood to be a “book”, which usually has to be read “successively”, from the first page to the last one.

The chapters of this workbook are structured according to shape. The first level is the size of the potential eye space of the group in question, the second level its form. There will be separate chapters for “Black to live” and “Black to kill”.

The level of the problems per chapter will increase from “closed borders & empty” to “open borders & filled”.

At the start of each chapter, there are some explanations of the “basic shape”. It is recommended to study these carefully, as they explain some important features of the shape that is currently in focus.

Thereafter, you can browse through the problems on your own:

● Go to the next problem,

● Tap your solution point at the board,

● Correct ? -> Fine, go to the next problem (if you do not want to know why you were correct),

● …,

● Mistaken ? -> Please do not worry, you may want to study the detailed solution on the next page and the shape’s structural elements thereafter.

● …,

● Bored, because “correct” is so very easy for you ? -> Go to the next shape.

This implies that the detailed explanations must be of the same kind with every problem, because it is the reader’s choice which one of these they will want to study first. But this does not mean that it is mandatory to study every solution and every shape analysis in order.

If you want to do only the problems, it is like browsing through a problem collection, but without random access. If you want to do some theory, you can do whenever you like, with whatever problem.

What might be quite unusual to this workbook is the transformation / transposition of many problems from “Black to kill” to “Black to live” or vice versa, interchanging the stones' colors. As a result, solutions may contain several subvariations which are more or less disadvantageous – in one aspect or the other. However, I suppose that it will be to your advantage to learn recognizing positions where you still have to add a stone, either to bring your group to live or to kill an opponent’s group. Even a slightly disadvantageous way of doing so will still be better than to have it the other way round, but fail.

Do not underestimate one-move problems

This workbook contains only problems that can be solved in one move (in principle), therefore it is suitable even for absolute beginners. Nearly everything is explained in much detail.

You will find a lot of variations that contain moves that may also successfully lead to the goal, but which cannot be considered to follow “optimal” play. Similarly, there will be candidate moves that will end in failure. The respective move sequences will often include more than only one move, so you will be gently introduced into more difficult aspects of the game.

In some of these variations, you will also encounter ko fights, which – in their basic shape – are at least three-move issues.

Please do not worry if any of these variations seems to be above your current level. Just go on and come back later.

When working on the first edition, I concentrated on shapes of a size up to five points. For larger shapes, it was by far more difficult to have application cases for “one-move tsume-go”. However, as expected at that time, a large supplement has been added in the meantime, resulting as a side-effect from my parallel work on “three-move tsume-go”.

Motivation

My beloved wife once asked me “You wrote some books about the most difficult problem ever created; why don’t you write a problem book for beginners?”

However, there are so many books on life & death problems available that it is difficult to add something valuable. During the work on my two books on “Tsume-Go Strategy”, the concept of this workbook came into my mind and I discussed it with my wife (being a member of the target audience). She was convinced that it would benefit potential readers, so I started.

I am sure that it is best to let the reader develop / find their own rules for solving problems, as well as for the exceptions from these rules. Every rule formulated by a third party (e.g. “Reduction first, then placement.”) might be misleading, especially in cases where this rule still works, but does not lead to the best solution.

Repetition matters, so I intended to include as many problems as possible. However, it needs a special attitude to always focus on following the same way of presenting and commenting solutions which may be quite similar (or even identical) to several ones before. Therefore, please be patient if you encounter a problem where it seems that I deviated a bit from the “usual” path.

Please take also into account that I am a strong Kyū player only when judging the accuracy of the presentation. This book contains about 1,100 problems and 20,000 diagrams, so please be forgiving if you find a fault in one of them. If you find anything better, or have a question, or a suggestion, please do not hesitate to report via the following email address:
igohatsuyoron120@gmail.com

Please also note that English is not my native language. Unfortunately, we were unable to find somebody who would be willing to go through each detail of the book, providing us with an external review. So please be forgiving if you come across a section that does not match the standards of a native speaker. If you find an inaccuracy or a mistake, please kindly use the email address above for reporting.

It is my hope that studying this workbook first of all is fun, assists you in getting stronger, and that it also makes you fascinated in the important field of tsume-go.

Berlin, May 2017
Thomas Redecker

Contents

The chapters in gray are included only in the full book.

One

Life

Death

● ○ ● ○ ● ○ ● ○ ● ○ ●

Two

Life

Death

● ○ ● ○ ● ○ ● ○ ● ○ ●

Three

Straight – Life

Straight – Death

Bent – Life

Bent – Death

● ○ ● ○ ● ○ ● ○ ● ○ ●

Four

Two vital points

Straight – Life

Straight – Death

Bent – Life

Bent – Death

Double-bent – Life

Double-bent – Death

● ○ ● ○ ● ○ ● ○ ● ○ ●

One vital point

Pyramid – Life

Pyramid – Death

● ○ ● ○ ● ○ ● ○ ● ○ ●

No vital point

Square – Life

Square – Death

● ○ ● ○ ● ○ ● ○ ● ○ ●

Five

Three vital points

Straight – Life

Straight – Death

Bent – Life

Bent – Death

Double-bent (S-type long) – Life

Double-bent (S-type long) – Death

Double-bent (U-type) – Life

Double-bent (U-type) – Death

W-shaped – Life

W-shaped – Death

Angle – Life

Angle – Death

Double-bent (S-type symm) – Life

Double-bent (S-type symm) – Death

● ○ ● ○ ● ○ ● ○ ● ○ ●

Two vital points

Pyramid + – Life

Pyramid + – Death

T-shaped – Life

T-shaped – Death

Labyrinthine – Life

Labyrinthine – Death

● ○ ● ○ ● ○ ● ○ ● ○ ●

One vital point

Bulky – Life

Bulky – Death

Cross – Life

Cross – Death

● ○ ● ○ ● ○ ● ○ ● ○ ●

Six

Four vital points

Straight – Life

Straight – Death

Bent (52) – Life

Bent (52) – Death

Double-bent (U-type) – Life

Double-bent (U-type) – Death

Triple-bent (n+) – Life

Triple-bent (n+) – Death

Bent (43) – Life

Bent (43) – Death

Triple-bent (W-type) – Life

Triple-bent (W-type) – Death

Double-bent (S-type) – Life

Double-bent (S-type) – Death

● ○ ● ○ ● ○ ● ○ ● ○ ●

Three vital points

Pyramid ++ – Life

Pyramid ++ – Death

+ Pyramid + – Life

+ Pyramid + – Death

Labyrinthine (u+) – Life

Labyrinthine (u+) – Death

Labyrinthine (h-Type) – Life

Labyrinthine (h-type) – Death

Labyrinthine (Y-Type) – Life

Labyrinthine (Y-type) – Death

● ○ ● ○ ● ○ ● ○ ● ○ ●

Two vital points

Bulky + (24) – Life

Bulky + (24) – Death

Bulky + (windmill) – Life

Bulky + (windmill) – Death

Bulky + (33) – Life

Bulky + (33) – Death

Bulky + (symm) – Life

Bulky + (symm) – Death

Bulky + (turning) – Life

Bulky + (turning) – Death

Rectangle – Life

Rectangle – Death

Triangle – Life

Triangle – Death

● ○ ● ○ ● ○ ● ○ ● ○ ●

One vital point

Flowery – Life

Flowery – Death

● ○ ● ○ ● ○ ● ○ ● ○ ●

Legend: Important shape points and further points of interest

This section introduces the symbols, and labels that are used in this book to highlight various important shape points.

"●"

circle

The potential eye space of a group (here a white one) is marked with "●".

Usually, this space is understood as the maximum that could be achieved (playing own moves for its fortification only).

“e”

eyepoint

Sure eye points are marked with “e”.

“△” / “” / “”

deadeyeshape

Dead eye shapes are marked with “△”. These might be partially occupied (“” / “”).

outsidestrong

Strong positions on the outside (preventing any escape), are marked with “” / “”.

outsidedescent

Important descents that have been played on the outside, and which look deep into the opponent’s position, are marked with “” / “”.

“□”

centralpoint_deadeyeshape

The central point of a dead eye shape is marked with “□”. It might be already occupied by the opponent (“”).

“●”

blackliberties

Liberties of black groups are marked with a black dot (●).

“○”

whiteliberties

Liberties of white groups are marked with a white dot (○).

“1” / “2” / “3” / “4” / “5”

libertycount

The liberty count of single stones, and entire groups of stones, is displayed by using the respective number on all involved stones.

Please be aware that – solely in the “Shape Analysis” – “1” is used for marking a single stone that has only one liberty left. Do not mismatch these stones with “moves”.

“✕” / “” / “”

falseeye

False eyes are marked with “✕”, the respective opponent stones engaged are marked with “” / “”.

falseeyeline

Lines of potential false eyes are marked with “✕” / “” / “”.

diagonalconnection

Stones, and groups (at their ends) that are not yet securely connected are marked with “” / “”.
These stones / groups may be diagonally adjacent to each other, or have a hole in-between.

zigzagline

A potential zigzag line of stones that should be connected out is marked with “✕” / “” / “”.

zigzaglinear

Please note that this term “zigzag line” is also used if the line of stones that should be connected out (, ✕) is positioned only on the first line.

To be honest, we simply did not find a better one.

stonecapture

Stones that cannot escape capture, or stones that could become captured easily, are marked with “” / “”.

“!!”

hole

The empty space (= hole) between a group, and the edge of the board, is marked with “!!”.

Gaps in the middle of encirclement are also marked with “!!”.

defect

Defects in the encirclement of a group are also marked with “!!”.

“??”

fakehole

The empty space (= hole) between a group, and the edge of the board, is marked with “??”, if it is only a subordinate shape issue and must not be addressed first. Following its fake hints will lead to failure.

Such fake gaps in the middle of encirclement are also marked with “??”.

fakedefect

Fake defects in the encirclement of a group are also marked with “??”. Following their fake hints will end in failure.

“◇”

jump

Points on the edge of the board that will serve as potential candidates for a jump from a friendly position ( here) are marked with “◇”.

“ko”

kocapture

The empty point that is left after capturing a single opponent stone in a ko shape (with Black 1 here) is marked with “ko”.

“n”

neutralpoint

Neutral points in a seki are marked with “n”.

“?”

uncertainarea

An area where it might be uncertain whether an eye can be developed there is marked with “?”.

“s”

sureeye

A sure eye that is already securely enclosed in an unfinished position is marked with s.

At the left, Black has solidly enclosed the s-point in the corner.

The s-point in the formation at the right is only loosely enclosed, but still cannot be destroyed by White. She needed two moves in a row, at A and at B, for doing so.

Please note that such points are not labeled with “e” (for “eye”).
Only one of these sure eyes does not guarantee life for Black’s group, and so it is very important to have a marker for the still unsettled status of a formation in question.

“p”

potentialeye

A potential eye that has an unsettled status in an unfinished position is marked with p.

At the left, Black can secure and White can destroy the potential eye at p with a move at A.

The formation at the right contains two potential eyes of which Black can secure two (resulting in the life of his group), but White can destroy only one (sufficient to kill Black’s group) with a move at B.

“+”

plus

“+” serves as a place marker for a move in discussion that is not placed on the board, to not destroy the impression of the original position.

Securing an eye space that consists of four points in a row (●) (formation at the left) …

… results in two sure eyes (s) for your group (formation at the right).

“+?”

plusquestionable

“+?” serves as a place marker for an at least questionable (or even mistaken) move in discussion that is not placed on the board, to not destroy the impression of the original position.

In the formation at the left, White will not really want to connect her two -stones that are in atari, because Black would capture three stones for a sure eye with a move at A.

Instead (formation at the right), White will capture Black’s single stone at the outside with her move at 1, threatening to kill Black’s group by connecting at B.

“SE”

singleemptypoint

“SE” servers as a place marker for a single empty point of the board in discussion that – in the majority of cases – must not be allowed to become occupied by the opponent.

In the formations above, occupying the last but one liberty of the SE-points (with moves at +) will hinder White from occupying these immediately, giving atari and killing Black’s groups.

Glossary

Atari

atari

The state of a stone or a group () which has only one liberty (○; and could be captured by the next move).
Very often used for the move itself (here: Black 1) which takes the penultimate liberty.

Descent

descent

＞＜

A move like Black 1, which descends towards the edge of the board.

Gote

Losing the initiative. A move which need not be answered.

Hane

hane

A diagonal move played from one’s own stone, in contact with and around an opponent stone.
Often facing the edge of the board.

Ko

ko-rule

＞＜

Shape in which the rules prohibit the immediate capture of a single stone (White 2) that has just captured a single stone at the prohibited point (ko).

Miai

miai

Two options with the same value, or purpose.
If one player takes one of them, the other one is left for the opponent (who is often forced to play there).

Seki

seki

Mutual life, shared life.
A configuration where groups of both colors share liberties, and are not independently alive. Neither side may capture any of their opponent stones without losing more points than they gain.

Sente

Initiative. A move which is answered.

Shortage of liberties

shortage of liberties

For example, Black cannot play at A to secure two eyes for his group without putting his own stones () in atari.

Throw-in

throw-in

＞＜

An aid to killing or capturing using a sacrifice stone, which results in a false eye shape (, ✕) and which is often used to prevent the opponent from connecting at that point, or to reduce eye space.

Tsume-Go

The field of “Life & Death” problems.

Conventions & Concepts

Table of contents

Solution sequence

● The outside group is unconditionally alive

● No need to take dead groups off the board

● Terminal diagram

● New diagram after every capture

● “Almost” fill means death

● “Not even almost” fill means life (in seki)

● “Owner” of a point

Shape Analysis

○ Equal valued alternative solutions

○ Semi-correct / suboptimal alternative solutions

○ Mistaken alternative solutions (= failures)

○ Fairy Dust

○ Misguidance

Move count

● Threatening & closing a hole in the encirclement

● Threatening & closing a defect in the encirclement

● Giving atari & connecting

● Giving atari & capturing

● Capturing a dead eye shape & occupying its vital point

● Occupying one of a dead eye shape’s vital point & occupying another one

● Reducing a dead eye shape & occupying the new vital point

● Threatening nothing & playing elsewhere

Ko fights

Determination of the “potential” eye space

○ Holes at the top

○ Holes at the edge of the board

○ Defects at the top

○ Defects at the edge of the board

○ Large holes at the side

○ Large holes from the third line of the board

○ Self-atari stops enlargement

Endgame Considerations

● Remaining stones in atari

● Open borders at the edge of the board

The solution sequence

The outside group is unconditionally alive

In tsume-go, it is assumed that the group on the “outside” of the problem ( here) is unconditionally alive, entirely independent from what will happen “inside”.

As a result, …

＞＜

… the tsume-go solution sequence ends here.

Black 1 occupied the central point of White’s eye space, so there is no option left for White to partition it.

White’s group cannot get more than only one eye, so is it dead as it stands.

No need to take dead groups off the board

There is no need to really take White’s stones off the board.

Please also note that this implies that this problem is of the “one-move” type, and not of the “seven-move” type when regarding all the moves necessary to take White’s group really off the board.

＞＜

Of course, White will not continue locally, but play elsewhere with 2.

Please note that the following sequence is only displayed for demonstrative purposes. It would not be played in a real game.

＞＜

Black wants to prove that he is able to take White’s stones off the board and starts with giving atari at 3.

＞＜

White does not want Black capturing her group, so she captures at 4 herself.

＞＜

Black 5 gives atari.

＞＜

Again, White does not want Black capturing her group, so she captures at 6 herself.

＞＜

But Black finally recaptures with 7, taking all of White’s stones off the board.

Terminal diagram

This is the final position.
This diagram shows the board after the end of the sequence shown above.

Please note that such kind of “terminal” diagram will be provided at the end of each variation of the solution sequence of all the “real” problems to come. Hopefully this will assist your understanding of the underlying shape.

New diagram after every capture

You will have noticed that a new diagram was created immediately …

… after White captured two black stones with her move 4 and …

… after she captured one black stone with her move 6, as the basis for the subsequent move(s).

I am sure that these new diagrams after every capture will make following the move sequences more convenient for you.

In the entire book, you will not find any “x at y” subscript below a diagram.

“Almost” fill means death

White’s eye space that consists of four points in a pyramid shape(●) …

… can be almost filled with a dead three-point eye shape (, △) at the bottom.

“Almost” means “all but one point”, which is equivalent to being able to give atari from the inside.

“Not even almost” fill means life (in seki)

Black’s eye space that consists of five empty points in a straight row (●) …

… can be not even almost filled with a dead three-point eye shape (, ) at the bottom.

White is unable to give atari at A, as Black would capture four white stones with a move at B for a living group. And vice versa.

This means that Black’s group is alive in seki.

“Owner” of a point

Being the “owner” of a point means that the opponent will not succeed in occupying this point with a permanent stone of their color.

Three cases will be discussed below.

● ○ ● ○ ● ○ ● ○ ● ○ ●

Black is the owner of the point of A, so B is a real eye.

In principle, Black is able to play elsewhere with 1. There is no urgent need to play at C, defending the hole in his encirclement; this move is only an endgame issue here.

＞＜

White’s hane at 2 threatens to kill Black’s group by continuing at 3, so Black has to block at 3, occupying the before vacant point that he “owned” already.

● ○ ● ○ ● ○ ● ○ ● ○ ●

Black is the owner of the point of A, so B and C are real eyes.

Black is able to play elsewhere with 1. There is no urgent need to defend the defect in his encirclement at the top.

＞＜

However, White has the forcing move at 2 up her sleeves, threatening to kill Black’s group by continuing at 3.

Black’s solid connection at 3 occupies the before vacant point that he “owned” already.

＞＜

Please note that White is unable to attack the defect in Black’s encirclement with playing at 2 herself; Black will simply capture at 3.

＞＜

“Ownership” is a very fragile issue, and must not be taken for granted; Black has to be on his guard here.

White’s atari at 4 from the outside must be answered with the solid connection at Black 5.

Otherwise, the “ownership” of the point of 5 will depend on the outcome of an uncalled-for ko fight for the life of Black’s group.

● ○ ● ○ ● ○ ● ○ ● ○ ●

＞＜

Black is the owner of the point of A, so White’s -stone cannot escape capture and will become Black’s second eye.

Please note that the point of A is taboo for White, so she will be unable to create a false black eye at the bottom right.

Black is able to play elsewhere with 1. There is no urgent need to erase the defect in his encirclement at the bottom right.

＞＜

However, White can give atari at 2 from the outside, threatening to kill Black’s group by further capturing at 3(so creating the desired false eye).

Black’s solid connection at 3 occupies the before vacant point that he “owned” already.

Shape Analysis

At the end of every problem you will find detailed explanations of the inner structure and the vital shape points of the starting position, as well as their interdependencies.

Equal valued alternative solutions

The starting moves of variations that are considered to be equivalent / equal valued to the main line of the solution are marked with the labels “E”, “F”, “G”, … .

The headlines of these variations are of the type
Variation E.

Semi-correct / suboptimal alternative solutions

The starting moves of variations that are considered to be semi-correct / suboptimal compared to the main line of the solution are marked with the labels “S”, “T”, “U”, … .

The headlines of these variations are of the type
Variation S.

Mistaken alternative solutions (= failures)

The starting moves of variations that are considered to be mistaken are marked with the labels “M”, “N”, “P”, … .

The headlines of these variations are of the type
Failure M (three-move).

In parenthesis you will find the type of the resulting problem (= the number of moves required for the refutation of the mistaken move).

Please note that only the resulting position after the mistaken alternative move will be displayed in the first diagram of a failure variation.
You will not find the mistaken move highlighted with its move number, to not give you any assistance for “learning” these wrong moves.

Fairy Dust

You surely know that fairy dust is just by good fairies and elves to materialize wishes of human beings who have a pure heart, and to let things appear more beautiful than they are in reality. The underlying intention is to have heart wishes come true.

Wishful thinking is our constant companion, also in the game of Go. We want to have it easy and comfortable. But sometimes we see things somewhat blurred.

The shape elements that will be explained in this section do have their significance – at least in general – but will not necessarily guide you to the optimal solution of the current problem.

Misguidance

Ever heard of a “will-o'-the-wisp”, a phosphorescent light seen hovering or floating at night on marshy ground, thought to result from the combustion of natural gases? It is said to recede if approached, drawing poor travelers looking for a safe place to stay for the night from the safe paths, because it resembles a flickering lamp.

Under this headline structural elements of the problem will be collected that have a similar effect to the reader, distracting their view from what is really important, also resulting in disaster.

Move count

A general nature of weaker players seems to be to answer almost every move of the opponent locally.

I thought for a long time about how to distinguish “one-move” problems from e.g. “three-move” problems. And wondered how there could be move pairs that are “obvious” even for beginners.

I concluded that it does not make sense to include an answer to an opponent’s forcing move in the move count of a problem, if this answer looks “obvious” and is played without thinking, “automatically”, as a kind of “reflex”.
You may understand problems that include “obvious” replies to forcing moves in their solution sequence as “one(+)-move tsume-go”.

Several application cases are discussed below.

Please note that these are written from the perspective of the “defender”, following the nature of the game.

Threatening & closing a hole in the encirclement

＞＜

White’s hane at 2 threatens the hole in Black’s encirclement at the bottom right.
Black has to answer by blocking at 3, in order to secure his second eye.

Please note that Black 3 is played directly adjacent to White’s forcing move.

Threatening & closing a defect in the encirclement

＞＜

White’s hane at 2 threatens the defect in Black’s encirclement at the bottom right.
Black has to answer by solidly connecting at 3, in order to secure his second eye.

Please note that Black 3 is played directly adjacent to White’s forcing move.

Giving atari & connecting

＞＜

White 2 gives double-atari at Black’s stones at the right.
Black has to solidly connect at 3, securing these stones as well as his second eye.

Please note that capturing a white stone is only a side-effect here. Even without this stone, White 2 would be an atari (at Black’s single stone at the top).

● ○ ● ○ ● ○ ● ○ ● ○ ●

＞＜

White 2 gives atari at Black’s three stones at the right.
Black has to solidly connect at 3, securing these stones as well as his second eye.

● ○ ● ○ ● ○ ● ○ ● ○ ●

＞＜

White 2 captures Black’s stone in the corner, also giving atari at Black’s single stone at the bottom right.

＞＜

Black has to solidly connect at 3, in order to save his threatened stone and also to destroy White’s potential eye at the right.

Giving atari & capturing

＞＜

White 2 gives atari at Black’s three stones at the right from the inside.
Black has to capture two white stones with a move at 3, securing his second eye.

● ○ ● ○ ● ○ ● ○ ● ○ ●

＞＜

White’s descent to 2 is also an atari at Black’s entire group.
Black has to capture at 3, taking White’s single stones inside his formation off the board and creating two eyes for his group.

Capturing a dead eye shape & occupying its vital point

＞＜

White 2 captures Black’s three stones in the corner which form a dead three-point eye shape inside her formation.

＞＜

Black 3 has to occupy the central and vital point of the now empty area, killing White’s group by reducing it to only one eye.

● ○ ● ○ ● ○ ● ○ ● ○ ●

Quite the contrary, …

＞＜

… this diagram shows an example, where both of Black’s moves have to be considered in the move count.

Black 1 cuts White’s position apart, destroying her potential eye at the right.
White 2 is a valid forcing move, capturing two black stones and

＞＜

… threatening to secure her second eye by continuing at 3.
Black has to throw-in at 7 turns her potential eye into a false one.

Capturing two black stones with White 2 has created a new empty space, forcing Black to carefully consider whether he has to invest another move or not.

Occupying one of a dead eye shape’s vital point & occupying another one

＞＜

White 2 occupies one of the vital points inside Black’s formation.
Black 3 has to take the other one, dividing his eye space into two eyes.

Reducing a dead eye shape & occupying the new vital point

＞＜

Black 1 is played at the second line, also gaining a living shape for his group.

Black has “reduced” the before bulky five-point dead eye shape (●) …

… that has only one vital point (□) …

… into a living bent line of four points (●) …

… that has two vital points now.

＞＜

Occupying one of these with White2 has to be answered by Black 3, occupying the other one.

Please note that such kind of “internal” forcing move will not be considered in the move count.

Threatening nothing & playing elsewhere

＞＜

White 2 gives atari at Black’s two stones at the top, but does not threaten the life of Black’s main group.
In principle, Black is able to play elsewhere with 3.

Please note that such “playing elsewhere” stops the move count, no matter how complicated a subsequent forcing sequence might be.

Of course, Black could answer White’s atari by solidly connecting at 4, saving his threatened stones, but this is only an endgame issue.

White 4 captures Black’s two stones above, also attacking the defect in his encirclement.

＞＜

Black has to recapture at 5, securing the defect in his encirclement – for the time being.

＞＜

White’s atari at 6 forces Black to solidly connect at 7, avoiding an uncalled for ko fight for the life of his group.

● ○ ● ○ ● ○ ● ○ ● ○ ●

＞＜

White 2 captures three black stones at the right, but does not threaten the life of Black’s main group in the corner.

＞＜

Black is able to play elsewhere with 3.

White’s solid connection at 4 forces Black to intercept at 5, also capturing White’s single stone in the corner.

Please note that White 4 is an indirect threat here.
Black’s answer at 5 is not directly adjacent to White’s forcing move, and so usually would have to be considered in the move count (but which has been stopped already by Black’s playing elsewhere here).

● ○ ● ○ ● ○ ● ○ ● ○ ●

＞＜

White 4 is a variation of the previous diagram, giving atari at Black’s entire group.

＞＜

Of course, Black 5 has to capture White’s three stones in the corner.

Please note that capturing opponent’s stones usually (please disregard a previous atari for a moment and also Black’s playing elsewhere before) will add to the move count of a problem.
Capturing more than one opponent’s stones will result in a position that is called “under the stones” and which usually seems to be quite difficult for weaker players to handle. You will have to be able to imagine what might happen in an area that is currently occupied by opponent’s stones, but will be empty very soon.

＞＜

White’s throw-in at 6 is a “normal” attack at the remaining hole in Black’s encirclement at the bottom.
Black has to block at 7, securing his second eye.

Ko fights

“Ko” is an advanced technique of the game, but it is also a three-move issue at least. Therefore, there will be no problems in this books that have this topic as their core theme.
However, you might find “ko” as the result of the refutation of a mistaken subvariation. Every of these ko fights will be shown in detail.

For the explanation of “ko fights” we will use a very simple example here.

We have combined a problem’s formation in the corner with a “standard” ko formation above.

＞＜

Black 1 captures White’s single stone.

＞＜

White is not allowed by the rules to immediately recapture at ko, but has to play somewhere else instead. Her hane at 2 threatens to continue at A, killing Black’s group in the corner.

＞＜

Black does not want this to happen – White would get much more of his stones than only the single one in the ko formation – and blocks at 3, securing two eyes for his group. White recaptures the ko at 4.

Now, the tables are turned, and Black has to find the next valid ko threat, in order to hinder White from connecting at ko, saving her single stone that is in atari.

Determination of the “potential” eye space

Problems that have the “inner” group surround an area (i.e. the eye space) with a solidly connected chain of stones () along the lines of the board are in the minority.

Usually, this encirclement is full of holes and defects, making it necessary to establish a method for determining the maximum area that this “inner” group can count on as “potential” eye space.

Below you will find my suggestion for doing so.

Holes at the top

Black’s partial groups are not yet solidly connected, leaving a hole (✕) in his encirclement at the top.

Hypothetically adding a stone (+) at this point (please forget about the correctness of a respective “move”) – following the lines of the board (>>) – will result in a solidly surrounded eye space that consists of three points in a row (●).

The same is true for Black’s potential eye space (●) in the original position.

● ○ ● ○ ● ○ ● ○ ● ○ ●

Black’s partial groups are not yet solidly connected, leaving a large hole (✕) in his encirclement at the top.

Of course, Black wants to maximize his potential eye space, so he will close the upper one.

Hypothetically adding a stone (+) at this point (please forget about the correctness of a respective “move”) – following the lines of the board (<<) – will result in a solidly surrounded eye space that consists of five points in a bulky shape (●).

The same is true for Black’s potential eye space (●) in the original position.

Holes at the edge of the board

Black’s group is not yet connected to the edges of the board, leaving two holes (✕) in his encirclement, one at the left and another one at the bottom right.

Hypothetically adding a stone (+) at the left – following the lines of the board (<<) – will result in a solid connection to the left edge.

Hypothetically adding another stone (+) at the bottom right (please forget about the correctness of a respective “move”) – following the lines of the board (v) – will result in a solidly surrounded eye space that consists of five points in a row (●).

The same is true for Black’s potential eye space (●) in the original position.

Defects at the top

Black’s partial groups are not yet solidly connected, leaving a defect (✕) in his encirclement at the top.

Hypothetically adding a stone (+) at this point – following the lines of the board (>>) – will result in a solidly surrounded eye space that consists of four points in a row (●).

The same is true for Black’s potential eye space (●) in the original position.

Defects at the edge of the board

Black’s partial groups at the right are not yet solidly connected, leaving a defect (✕) in his encirclement at the bottom.

Hypothetically adding a stone (+) at this point (please forget about the correctness of a respective “move”) – following the lines of the board (v) – will result in a solidly surrounded eye space that consists of three points in a bent line (●).

The same is true for Black’s potential eye space (●) in the original position.

● ○ ● ○ ● ○ ● ○ ● ○ ●

Black’s partial groups at the left are not yet solidly connected, leaving a defect (✕) in his encirclement at the bottom.

Hypothetically adding a stone (+) at this point (please forget about the correctness of a respective “move”) – following the lines of the board (v) – will result in a solidly surrounded eye space that consists of four points in a double-bent line (●).

The same is true for Black’s potential eye space (●) in the original position.

Large holes at the side

At the right, Black’s group is not yet solidly connected to the edge of the board, leaving a large hole (✕) at the side.

Please note that Black has some space at the second line to maneuver.

Hypothetically adding a stone (+) at the second line (please forget about the correctness of a respective “move”) – following the lines of the board (>>) – expands Black’s formation to the right.

Please note that Black is “bumping” against White’s already existing -stone that stops his further encroachment to the right, so Black’s action will be left without “answer”.

Hypothetically adding another stone (+) at the bottom right (please forget about the correctness of a respective “move”) – following the lines of the board (v) – will result in a solidly surrounded eye space that consists of a two-point section at the right and a one-point one in the corner (that was existing from the very beginning) (●).

The same is true for Black’s potential eye space (●) in the original position.

● ○ ● ○ ● ○ ● ○ ● ○ ●

At the right, Black’s group is not yet solidly connected to the edge of the board, leaving a large hole (✕) at the side.

Please note that Black has some space at the second line to maneuver.

Hypothetically adding a stone (+) at the second line (please forget about the correctness of a respective “move”) – following the lines of the board (>>) – expands Black’s formation to the right.

White stops Black’s further encroachment to the right by adding a stone herself (+), blocking at the second line.

Hypothetically adding another stone (+) at the bottom right (please forget about the correctness of a respective “move”) – following the lines of the board (v) – will result in a solidly surrounded eye space that consists of a two-point section at the right and a one-point one in the corner (that was existing from the very beginning) (●).

The same is true for Black’s potential eye space (●) in the original position.

Large holes from the third line of the board

The more “open” a position is and the larger the holes to close, the more “artificial” becomes the determination of the “potential” eye space, but this cannot be helped.

At the right, Black’s group is not yet solidly connected to the edge of the board, leaving a very large hole (✕) at the side.

Please note that Black has some space at the second ant the third lines to maneuver.

Hypothetically adding a stone (+) at the second line with a distance – following the lines of the board (>>) – expands White’s formation to the right.

Please note that White’s added stone cannot be “captured” by Black.

Black stops White’s further encroachment to the right by adding a stone himself (+), blocking at the second line.

Hypothetically adding another stone (+) at the bottom right – following the lines of the board (v) – will connect White’s formation to the bottom line.

Please note that this action will be left without “answer”.

Hypothetically adding a third stone (+) at the third line (please forget about the correctness of a respective “move”) – following the lines of the board (v) – closes the remaining hole in White’s formation and will result in a solidly surrounded eye space that consists of six points in a labyrinthine shape (●).

The same is true for Black’s potential eye space (●) in the original position.

Self-atari stops enlargement

Black’s partial groups are not yet solidly connected, leaving a large hole (✕) in his encirclement at the top.

Of course, Black wants to maximize his potential eye space, so he wants to close the upper one.

However, with hypothetically adding a stone at +? at the third line Black has put his own stones at the right in (self-) atari, so this option cannot be considered to be a valid one.
Black will have to close the lower hole.

Hypothetically adding a stone (+) at the second line (please forget about the correctness of a respective “move”) – following the lines of the board (>>) – will result in a solidly surrounded eye space that consists of three points in a row (●).

The same is true for Black’s potential eye space (●) in the original position.

● ○ ● ○ ● ○ ● ○ ● ○ ●

At the right, Black’s group is not yet solidly connected to the edge of the board, leaving a hole / defect (✕) at the side.

Of course, Black wants to maximize his potential eye space, so he wants to erase the hole at the far right.

However, with hypothetically adding a stone at +? Black has put his own stones at the right in (self-) atari, so this option cannot be considered to be a valid one.
Black will have to close the defect instead.

Hypothetically adding a stone (+) at the second line – following the lines of the board (v) – will result in a solidly surrounded eye space that consists of four points in a bent line (●).

The same is true for Black’s potential eye space (●) in the original position.

(#ccendgame) Endgame Considerations

Endgame considerations do not play a role in tsume-go that examines questions of life and death only.
However, you might want to think for yourself about the implications of a final position embedded in a real game and about the values of different forcing moves that arose during the course of a problem’s variation.

The larger the shape of the problem in question, the more the boundaries between “correct” and “semi-correct” become blurred. Basically, there are more move options for both sides and – especially in a real game – several aspects of the game to consider which – in the narrow sense – have nothing to do with tsume-go.

It was impossible for me to reliably measure the effect of all the implicit factors from the fields outside tsume-go. Therefore, the various options for alternative moves will be usually ordered according to the number of remaining forcing moves for the opponent.
Similarly – when counting forcing moves – we will not take into account whether some of these might be “disadvantageous” in the sense that their initiator will lose points if these forcing stones become captured later.

Two examples will be discussed below.

Remaining stones in atari

In the exemplary diagram above, White ended with her -stone being in atari, so connecting (by White) or capturing (by Black) by playing at the point of A are the two cases to be examined in the endgame stage of the game.

● ○ ● ○ ● ○ ● ○ ● ○ ●

＞＜

If it’s White to play, she will connect at 2.

Please note that his move is gote.

White has saved her -stone and has five points of territory (●) in the marked area at the bottom right.

● ○ ● ○ ● ○ ● ○ ● ○ ●

＞＜

If it’s Black to play, he will capture White’s -stones with a move at 1, gaining one point.
Let us assume that White wants to defend valuable territory at the bottom right, so she will answer at 2.

＞＜

Black connects at 3, saving his just played stone.

Please note that Black also ended in gote her, so both variations are comparable.

At the right, White has four point of territory (●), one point less than above.

● ○ ● ○ ● ○ ● ○ ● ○ ●

The difference between both final diagrams is two points, so – on average – a move at A has an endgame value of one point.

Please note that we were often unable to consider such endgame issues when evaluating whether a solution is “correct” or “semi-correct”.
Therefore, we usually prefer the move that provides White with fewer forcing moves.

● ○ ● ○ ● ○ ● ○ ● ○ ●

The larger the shape becomes the more difficult it is to find a forcing move that does not involve a potential loss for its initiator.

Here in this exemplary case, …

＞＜

… White has the forcing move of 2, threatening to kill Black’s group by continuing at 3.

However – in a real game – White might want to think twice before using this move as a ko threat, as Black’s block at 3 gives atari at her three stones at the bottom. Further capturing with Black A later will provide White with a quite large local loss.

Open borders at the edge of the board

All problems in this book are designed in such a way that the “inner” group in question is locked either in the corner, in the side or in the centre.

In the exemplary diagram above, White’s two -stones make sure that Black’s group cannot escape the corner area.

However, in a real game the surrounding positions might differ. Two examples will be discussed below.

● ○ ● ○ ● ○ ● ○ ● ○ ●

White’s single stone at the right has been taken off the board – for demonstrative purposes. Please further assume that White has built up potential territory (○) at the lower edge.

＞＜

Black’s descent to 1 at the right is now the “natural” choice.
It does not only bring Black’s group to live, but also serves as a kind of submarine attack, undermining White’s formation at the lower edge and threatening to continue at A.

● ○ ● ○ ● ○ ● ○ ● ○ ●

On the other hand, if White’s -stone at the left changed place – as shown here for demonstrative purposes – again assuming white potential territory (○) at the left edge …

＞＜

… Black will choose the connection at 1 at the left to bring his group to live, now undermining White’s left side, threatening her potential territory (?) in that area.

One – Life

Index of Problems

Problem O0001

Black’s group in the corner is dead as it stands.

Black’s group surrounds an area that consists of only one point (●).

Black’s group has only one liberty (●).

＞＜

Black cannot do anything locally.
But White is able to take Black’s group off the board by playing at 2.

Please note that White will not do so in a real game.

In tsume-go, it is assumed that the group on the “outside” of the problem is unconditionally alive, entirely independent from what will happen “inside”.

As a result, White’s move 2 above would lose one point of white territory unnecessarily.

This is the final position.

● ○ ● ○ ● ○ ● ○ ● ○ ●

But let’s return to the original formation now.

We have identified the first dead eye shape, the one-point dead eye shape △.

One – Death

Index of Problems

Problem O0002

White’s group in the corner is dead as it stands.

White’s group surrounds an area that consists of only one point (●).

White’s group has only one liberty (○).

＞＜

Black is able to take White’s group off the board by playing at 1.

Please note that Black will not do so in a real game.
In tsume-go, it is assumed that the group on the “outside” of the problem is unconditionally alive, entirely independent from what will happen “inside”.
As a result, Black’s move 1 above would lose one point of black territory unnecessarily.

This is the final position.

● ○ ● ○ ● ○ ● ○ ● ○ ●

But let’s return to the original formation now.

We have identified the first dead eye shape, the one-point dead eye shape △.

Two – Life

Index of Problems

Problem O0003

Black’s group in the corner is dead as it stands.

Black’s group surrounds an area that consists of only two connected points (●).

Black’s group has only two liberties (●).

＞＜

Black cannot do anything locally.
But White is able to take Black’s group off the board by starting with the atari of 2.

Please note that this sequence is only displayed for demonstrative purposes. It would not be played in a real game.

＞＜

It is fruitless for Black to capture White’s single stone with 3.

Black has only one liberty (●) left.

＞＜

White 4 takes all of Black’s stones off the board.

This is the final position.

● ○ ● ○ ● ○ ● ○ ● ○ ●

But let’s return to the original formation now.

You will realize that the empty space inside Black’s formation can be almost filled by White with what we already know to be a dead shape – the one-point shape △.

“Almost” means “all but one point”, which is equivalent to give atari from the inside.

This implies that we have identified another dead eye shape, the two-point dead eye shape △.

Two – Death

Index of Problems

Problem O0004

White’s group in the corner is dead as it stands.

White’s group surrounds an area that consists of only two connected points (●).

White’s group has only two liberties (○).

＞＜

White cannot do anything locally.
But Black is able to take White’s group off the board by starting with the atari of 1.

Please note that this sequence is only displayed for demonstrative purposes. It would not be played in a real game.

＞＜

It is fruitless for White to capture Black’s single stone with 2.

White has only one liberty (○) left.

＞＜

Black 3 takes all of White’s stones off the board.

This is the final position.

● ○ ● ○ ● ○ ● ○ ● ○ ●

But let’s return to the original formation now.

You will realize that the empty space inside White’s formation can be almost filled by Black with what we already know to be a dead shape – the one-point shape △.

“Almost” means “all but one point”, which is equivalent to give atari from the inside.

This implies that we have identified another dead eye shape, the two-point dead eye shape △.

Three (straight) – Life

Index of Problems

Problem O0005

The status of Black’s group is unsettled.

Black’s group surrounds an area that consists of three connected points (●), which are arranged in a straight row.

Please note that this is the smallest possible formation that can be transformed into an independently living group.

Black’s group has three liberties (●) inside his formation.

In order to reach a living shape, Black will have to prevent that White almost fills the empty space inside his formation with the dead two-point shape (△) shown at the left.

And also hinder White from establishing this dead two-point shape (△) at the right. There is only one option for doing so successfully.

＞＜

Black 1 occupies the central point of his eye space.

Now, Black’s group surrounds two single points (●), one point less than before.

Black’s group has two liberties (●), one liberty less than before. However, neither the loss of one point of (probably potential) territory nor the loss of one liberty matters here.
The all-decisive fact is that these two points / liberties have been separated from each other by Black’s move.

As a result, these points have become eyes (e) of Black’s group.

White is not allowed by the rules to place a stone at no, Black’s eye point at the right. Black’s group has a remaining liberty at ●, but White’s stone is without any liberty; such kind of move (suicide) is forbidden by the rules.

The same is true for Black’s left-hand eye point. White’s move at no is forbidden by the rules, because Black’s group still has a liberty at ●.

As a result, White cannot capture Black’s group, so Black is alive.

● ○ ● ○ ● ○ ● ○ ● ○ ●

But let’s return to the original formation now.

We have found another shape that will affect the life & death status of a group. Black’s eye space can be entirely filled with a dead three-point eye shape (△).

The vital point of this three-point shape is its central point (□) which is still unoccupied.

In order to simplify the presentation, the two previous diagrams will be combined to only one, as shown here.

The dead eye shape is highlighted by △ and □; □ is its decisive central point.

Problem O0006

＞＜

< Go to the next problem >

< Return to the index >

< This problem as “Black to kill” >

< Go to the next chapter >

Solution

＞＜

Black 1 occupies the central point of his eye space, successfully dividing it into two eyes.

Black’s group is alive.

Shape Analysis

Black’s eye space can be filled with a dead three-point eye shape (△, □) which central point is still unoccupied.

Misguidance

Please note that Black’s outside liberties (●) do not matter here.

Problem O0008

＞＜

< Go to the next problem >

< Return to the index >

< This problem as “Black to kill” >

< Go to the next chapter >

Solution

＞＜

Black 1 occupies the central point of his eye space, successfully dividing it into two eyes.

Black’s group is alive.

Shape Analysis

Black’s eye space can be filled with a dead three-point eye shape (△, □) which central point is still unoccupied.

Problem O0009

＞＜

< Go to the next problem >

< Return to the index >

< This problem as “Black to kill” >

< Go to the next chapter >

Solution

＞＜

Black 1 occupies the central point of his eye space, successfully dividing it into two eyes.

Black’s group is alive.

Shape Analysis

Black’s eye space can be filled with a dead three-point eye shape (△, □) which central point is still unoccupied.

Problem O0007

＞＜

< Go to the next problem >

< Return to the index >

< This problem as “Black to kill” >

< Go to the next chapter >

Solution

＞＜

Black 1 occupies the central point of his eye space, successfully dividing it into two eyes.

Black’s group is alive.

Black must not mistakenly capture White’s single stone at the right, with a move at M, instead.

Failure M (one-move)

This diagram shows the position after Black mistakenly captured White’s single stone at the bottom right.

＞＜

White 2 occupies the central point of Black’s eye space that Black should have taken beforehand.

There is no option left for Black to partition his eye space, so his group is dead.

At the right, there is only a false eye (✕, ) for Black.

It will be shown now that f is no real eye for Black.

Please note that the following sequence is only displayed for demonstrative purposes. It would not be played in a real game.

＞＜

Black will not continue locally, but play elsewhere with 3.
White 4 gives atari. Black will not connect, but play elsewhere again with 5.
White 6 captures Black’s single stone.

＞＜

Black can do nothing more than playing elsewhere again with 7, where after White connects at 8.

Black’s previously false eye is now filled with white stones.

Black is left with only one real eye in the corner, so his group is dead.

Shape Analysis

Black’s eye space can be filled with a dead three-point eye shape (△, □) which central point is still unoccupied.

Misguidance

White’s single stone at the right has only one liberty and so is in immediate danger of becoming captured by Black.

However, in tsume-go you should always think twice before really capturing opponent’s stones that are in atari, especially if it’s only one of their stones and if these stones are located on the outskirts of your formation.

At the right, there is already a false eye ().

Problem O0010

＞＜

< Go to the next problem >

< Return to the index >

< This problem as “Black to kill” >

< Go to the next chapter >

Solution

＞＜

Black 1 occupies the central point of his eye space, successfully dividing it into two eyes.

Black’s group is alive.

Please note that Black’s move also captures White’s single stone, but this feature is not the main theme of this problem. It’s rather a kind of side-effect that cannot be avoided.
Capturing opponent’s stones might be thrilling, but doing so in tsume-go – especially in more difficult problems – in the very beginning of the solution sequence will very often result in failure.
Therefore, always consider carefully whether there is reasoning for your capturing move.

Shape Analysis

Black’s eye space can be filled with a dead three-point eye shape (△, □, ) which central point is still unoccupied.

Fairy Dust

White’s single stone has only one liberty and so is in immediate danger of becoming captured by Black.

Life

Part 2

This section contains a subset of the straight three-point eye shape with its central point already occupied.

Problem O0011

＞＜

< Go to the next problem >

< Return to the index >

< This problem as “Black to kill” >

< Go to the next chapter >

Solution

＞＜

Black 1 closes the hole in his encirclement, securing his second eye.

Shape Analysis

Black’s potential eye space consists of two already separated points (●).

In the corner, Black has solidly enclosed one eye (s).

The hole (!!) in Black’s encirclement at the right needs reinforcement.

Problem O0013

＞＜

< Go to the next problem >

< Return to the index >

< This problem as “Black to kill” >

< Go to the next chapter >

Solution

＞＜

Black connects at 1, erasing the defect in his encirclement and securing his second eye.

Shape Analysis

Black’s potential eye space consists of two already separated points (●).

In the corner, Black has solidly enclosed one eye (s).

The defect (!!) in Black’s encirclement at the right needs reinforcement.

Fairy Dust

Black’s partial groups are not yet solidly connected ().

At the right, you can see a potential line of false eyes (, ✕).

Black’s -stone at the right does not affect the life & death status of Black’s main forces here.

You will always have to distinguish carefully between really decisive and more or less unimportant elements of the problem.

Please note that it will not affect the core structure of the problem, if this black stone it taken off the board – for demonstrative purposes.

You will realize that there is a hole (!!) in Black’s encirclement that needs reinforcement. This implies that the main task is not “connect a stone”, but “close a hole”.

Problem O0014

＞＜

< Go to the next problem >

< Return to the index >

< This problem as “Black to kill” >

< Go to the next chapter >

Solution

＞＜

Black 1 closes the hole in his encirclement, securing his second eye.

Shape Analysis

Black’s potential eye space consists of two already separated points (●).

In the corner, Black has solidly enclosed one eye (s).

The hole (!!) in Black’s encirclement at the right needs reinforcement.

Problem O0015

＞＜

< Go to the next problem >

< Return to the index >

< This problem as “Black to kill” >

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Solution

＞＜

Black connects at 1, erasing the defect in his encirclement and securing his second eye.

Shape Analysis

Black’s potential eye space consists of two already separated points (●).

In the corner, Black has solidly enclosed one eye (s).

Black’s partial groups are not yet solidly connected ().

At the right, you can see a potential line of false eyes (✕).

This formation at the right is equivalent to a defect (!!) in Black’s encirclement that needs reinforcement.

Please note that this “defect” in Black’s encirclement has the same effect as a “hole”, but might be a bit more difficult to identify.

However, if – for demonstrative purposes – the “bent” structure at the right (, !!, ) is transformed …

… into a “straight” one, you will easily recognize that there is a deep hole (!!) in Black’s encirclement that needs reinforcement.

Problem O0016

＞＜

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Solution

＞＜

Black connects at 1, erasing the defect in his encirclement and securing two eyes.

Shape Analysis

Black’s potential eye space consists of two already separated points (●).

None of these points (?) can be considered a sure eye point yet.

Black’s partial groups are not yet solidly connected ().

On the bottom, you can see two potential lines of false eyes (✕) which share their end point at the second line.

Please note that White needed to occupy this shared point to make these lines work.

This formation is equivalent to a defect (!!) in Black’s encirclement that needs reinforcement.

Problem O0017

＞＜

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Solution

＞＜

Black 1 closes the hole in his encirclement, securing his second eye.

Shape Analysis

Black’s potential eye space consists of two already separated points (●).

At the right, Black has solidly enclosed one eye (s).

The hole (!!) in Black’s encirclement at the left needs reinforcement.

Problem O0019

＞＜

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Solution

＞＜

Black 1 closes the hole in his encirclement, securing his second eye.

Shape Analysis

Black’s potential eye space consists of two already separated points (●).

In the corner, Black has solidly enclosed one eye (s).

Black’s partial groups are not yet solidly connected ().

You can see a potential line of false eyes (, ✕).

The hole (!!) in Black’s encirclement at the top needs reinforcement.

Problem O0020

＞＜

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Solution

＞＜

Black connects at 1, erasing the main defect in his encirclement and securing two eyes.

Black might consider playing at S or at T instead. These moves will also successfully bring Black’s group to life, but might contain a tiny disadvantage.

At the left, the points of A and B are miai, so C is a real eye.

At the right, the points of D and E are miai, so F is a real eye.

＞＜

White does not have immediate forcing moves that could be utilized in a ko fight elsewhere on the board.
After White’s descent to 2 at the left, Black can play elsewhere with 3.
White 4 and Black 5 are miai.
After White’s atari at 6 at the right, Black can play elsewhere again with 7.
After White 8 captures Black’s single stone, …

＞＜

… Black 9 occupies the miai point.

Black’s group is alive with two eyes.

Variation S

＞＜

Black 1 solidly connects at the left, erasing an only subordinated defect in his encirclement.

＞＜

However, White has the forcing move at 2 up her sleeves – threatening to activate the marked line of false eyes (2, ✕) at the right– that could be utilized in a ko fight elsewhere on the board.

＞＜

Black will connect at 3. White’s descent to 4 is another forcing move – threatening to activate the marked line of false eyes (, ✕) at the left.

＞＜

Black will connect at 5. White’s descent to 6 is yet another forcing move – threatening to capture Black’s single stone in order to activate the marked line of false eyes (, ✕) at the right, starting an uncalled-for ko fight for the life of Black’s group.

＞＜

Black will connect at 7.

Black’s group is alive, but he suffered from three uncalled-for white forcing moves.

Variation T

＞＜

Black 1 solidly connects at the right, again erasing an only subordinated defect in his encirclement.

＞＜

Black’s formation is nearly symmetrical, so White has the same uncalled-for forcing moves as seen just before.

Shape Analysis

Black’s potential eye space consists of two already separated points (●).

Black’s partial groups are not yet solidly connected ().

At the left, you can see a potential line of false eyes (✕).

Please note that White needed to occupy both ends of this line to make it work.

At the right, you can see another potential line of false eyes (✕).

Again, White needed to occupy both ends of such a line to make it work.

You will surely have noticed that both lines of false eyes share one point.

Black’s formation at the top is symmetrical, so the central defect (!!) in his encirclement is the really decisive one that needs reinforcement.

You will always have to distinguish carefully between really decisive and more or less unimportant defects, before making up your mind which one of these to reinforce. Here in this problem, additionally evaluating the potential lines of false eyes will provide you with the decisive clue.

Fairy Dust

The defects (!!) in Black’s encirclement at the right and at the left are of only minor importance and will not be the best starting points for him.

These points are not supported by a second “strong” line of false eyes.

At the left, you can see a potential line of false eyes (✕), but White is effectively hindered in occupying its second end point at the first line.

At the right, you can see another potential line of false eyes (✕), but White is effectively hindered in occupying its second end point at the first line.

Problem O0021

＞＜

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Solution

＞＜

Black 1 closes the hole in his encirclement, securing his second eye and also capturing White’s single stone.

Black must not mistakenly play at M, instead, preventing his single stone at the right from becoming captured immediately.

Failure M (three-move)

Black just extended at the right.

＞＜

White also extends to 2, sacrificing two stones instead of only one, turning Black’s potential eye at the right into a false one.

Black has only one eye in the corner, so his group is dead.

＞＜

It is fruitless for Black to capture White’s two stones.

＞＜

White throws in at 4, preventing Black from getting a real eye at the right.

Shape Analysis

Black’s potential eye space consists of two already separated points (●).

In the corner, Black has solidly enclosed one eye (s).

The hole (!!) in Black’s encirclement at the right needs reinforcement.

Misguidance

Black’s partial groups are not yet solidly connected ().

At the right, there is already a false eye ().

Also at the right, both White’s and Black’s single stones have only one liberty, and so are in danger of becoming captured.

However, this mutual atari might be only on the board to bedazzle your mind.

Black’s -stone at the right does not affect the life & death status of Black’s main forces here.

Please note that it will not affect the core structure of the problem, if this black stone it taken off the board for demonstrative purposes.

You will realize that there still is a hole (!!) in Black’s encirclement that needs reinforcement.

Problem O0022

＞＜

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Solution

＞＜

Black 1 closes the hole in his encirclement, securing his second eye and also capturing White’s single stone.

Black might consider playing at S instead. This move will also successfully bring Black’s group to live, but it might contain a tiny disadvantage.

Variation S

＞＜

Black plays hane at 1 to the right.

Black is the owner of the point of A, so White’s -stone cannot escape capture and will become Black’s second eye.

＞＜

However, White has the forcing move at 2 up her sleeves – threatening to kill Black’s group by further capturing at 3 – that could be utilized in a ko fight elsewhere on the board.

Shape Analysis

Black’s potential eye space consists of two already separated points (●).

In the corner, Black has solidly enclosed one eye (s).

The hole (!!) in Black’s encirclement at the right needs reinforcement.

Fairy Dust

White’s single stone has only one liberty, and so is in danger of becoming captured immediately.

White’s stones at the right () are strong, looking forward to supporting a friendly stone at ◇, but positioned on the second line only.

Black might have additional options to securely immobilize White’s single stone.

Occupying the last liberty of a single, empty point of the board (SE) might hinder your opponent from occupying it immediately.

Please note that it will not affect the core structure of the problem, if White’s single stone inside Black’s formation it taken off the board for demonstrative purposes.

The hole (!!) in Black’s encirclement remains as before. This implies that the main task is not “capture a stone”, but “close a hole”.

Problem O0023

＞＜

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Solution

＞＜

Black 1 closes the hole in his encirclement, securing his second eye and capturing White’s single stone.

Black might consider playing at S or at T instead. These moves will also successfully bring Black’s group to live, but might contain a tiny disadvantage.

Variation S

＞＜

Black’s diagonal move at 1 protects the hole in his formation by immobilizing White’s single stone at the first line, also securing his second eye at the right.

Black is the owner of the point of A, so White’s -stone cannot escape capture and will become Black’s second eye.

＞＜

However, White has the forcing move at 2 up her sleeves – threatening to kill Black’s group by further capturing at 3 – that could be utilized in a ko fight elsewhere on the board.

Variation T

＞＜

Black’s solid move at 1 also protects the hole in his formation, securing his second eye at the right.

＞＜

However, White has the forcing move at 2 up her sleeves – threatening to kill Black’s group by further capturing at 3 – that could be utilized in a ko fight elsewhere on the board.

These two moves are miai.

Subvariation for White 2

＞＜

If White does not mind losing two points for generating an additional forcing move, she can change to order of moves and start with 2 here. Black is forced to capture at 3.

＞＜

Here, Black’s partial groups are not connected, so White 4 is an atari that has to be answered by Black 5.

Please note that Black captured three white stones here, two more than in the main line of this variation.

Shape Analysis

Black’s potential eye space consists of two already separated points (●).

In the corner, Black has solidly enclosed one eye (s).

Black’s partial groups are not yet solidly connected ().

The defect (!!) in Black’s encirclement at the top right needs reinforcement.

Both black partial groups have only two liberties, and so are very vulnerable to an attack.

Please note that one of these liberties is shared (●). This implies that these groups could easily fall prey to a double-atari.

Fairy Dust

White’s single stone inside Black’s formation has only one liberty, and …

… seems already lost deep inside Black’s formation.

Black might have additional options for immobilizing White’s -stone.

The large hole (!!) outside Black’s encirclement at the top is not the best starting point for him.

Please note that Black is unable to occupy both marked points, due to his shortage of liberties at the right.

Occupying the last liberty of a single, empty point of the board (SE) might hinder your opponent from occupying it immediately.

Problem O0024

＞＜

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Solution

＞＜

Black 1 closes the hole in his encirclement, securing his second eye at the left and also capturing White’s single stone.

Shape Analysis

Black’s potential eye space consists of two already separated points (●).

At the bottom, Black has solidly enclosed one eye (s).

The hole (!!) in Black’s encirclement at the left needs reinforcement.

Misguidance

Black’s partial groups are not yet solidly connected ().

Please note that this fact does not matter here.
You will always have to distinguish between important and unimportant elements of your entire formation.

Both Black’s -stone at the right and the mutual atari at the left do not contribute to the core structure of the problem.

However, in tsume-go you will often find such more or less “unimportant” elements – especially at the problem’s outskirts – that are only added to the problem to bedazzle your mind.

Please note that it will not affect the core structure of the problem, if these elements are taken off the board – for demonstrative purposes – and the problem’s setup is adjusted accordingly.

The decisive hole (!!) in Black’s encirclement at the left remains as before.

Problem O0028

＞＜

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Solution

＞＜

Black 1 occupies the central point of his eye space, successfully dividing it into two eyes and also capturing White' single stone inside his formation.

Black’s group is alive.

Black must not mistakenly play at M, instead, capturing White’s single stone at the right.

Failure M (one-move)

Black just captured White’s single stone at the right.

＞＜

White 2 occupies the central point of Black’s eye space that Black should have taken beforehand.

There is no option left for Black to partition his eye space, so his group is dead.

Shape Analysis

Black’s eye space consists of three empty points in a row (●).

The central point of the dead three-point eye shape (△, □, ) is still unoccupied.

Misguidance

At the right, both Black’s and White’s single stones have only one liberty, and so are in danger of becoming captured.

You will find this situation quite often in tsume-go problems. However, this mutual atari might be only on the board to bedazzle your mind.

Always think twice before really capturing a single opponent’s stone, especially if it is located at the outskirts of your formation.

Black’s partial groups are not yet solidly connected ().

However, please note that this fact does not affect the life & death status of Black’s main forces here.
You will always have to distinguish between important and unimportant parts of your entire formation.

At the right, there is already a false eye ().

In principle, the formation at the right is equivalent to a hole (??) in Black’s encirclement.

However, you will realize that there is no empty space between this “hole” and Black’s already existing -stone on the first line here. Therefore, “defending” this “hole” does not make sense at all.

Life

Part 3

Problem O0026

＞＜

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Solution

＞＜

Black 1 occupies the central point of his potential eye space, successfully dividing it into two eyes.

Black’s group is alive.

Black must not mistakenly play at M, instead, closing the hole in his formation immediately.

Black is the owner of the point of A, so B and C are real eyes.

＞＜

However, White has the forcing move at 2 up her sleeves – threatening to kill Black’s group by continuing at 3 – that could be utilized in a ko fight elsewhere on the board.

Failure M (one-move)

Black just closed the hole in his formation.

＞＜

White 2 occupies the central point of Black’s eye space that Black should have taken beforehand.

There is no option left for Black to partition his eye space, so his group is dead.

Shape Analysis

Black’s potential eye space consists of three empty points in a row (●).

The central point of the dead three-point eye shape (△, □) is still unoccupied.

Fairy Dust

Black’s partial groups are not yet solidly connected ().

You can see two potential lines of false eyes (✕).

Please note that White needed to occupy their shared end point at the second line to make these lines work.

Occupying the last but one liberty of a single, empty point of the board (SE) might hinder your opponent from occupying it immediately.

Misguidance

The hole (??) in Black’s encirclement at the top must not be closed directly.

Please note that it does not make sense to consolidate the borders of your formation – in an attempt to maximize your potential eye space – if you are leaving behind only a dead eye shape which central point is still unoccupied.

Problem O0027

＞＜

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Solution

＞＜

Black 1 closes the hole in his encirclement.

Black must not mistakenly play at M, instead, capturing White’s single stone in the corner.

White’s single -stones cannot escape capture, so they will become black eyes. The point of A is taboo for White.

＞＜

However, White has the forcing move at 2 up her sleeves – threatening to kill Black’s group by continuing at 3 – that could be utilized in a ko fight elsewhere on the board.

Failure M (three-move)

Black just captured White’s single stone in the corner.

＞＜

White extends to 2, occupying the vital point of the problem that Black should have taken beforehand, sacrificing two stones instead of only one in order to spoil Black’s shape.

＞＜

Black 3 captures two white stones, but he will be unable to create a second eye for his group.

＞＜

White throws in at 4, turning Black’s potential eye at the right into a false one.

Black has only one eye in the corner, so his group is dead.

Shape Analysis

White’s potential eye space consists of three points in a row (●).

The hole (!!) in Black’s encirclement at the right needs reinforcement.

At the right, you can see a potential line of false eyes (, ✕).

Misguidance

Black’s potential eye space can be filled with a dead three-point eye shape (, □) which central point is still unoccupied.

It is important to recognize that this shape is an invalid one here; following its fake hints will lead to failure.

White’s single stone in the corner has only one liberty, and so could be captured by Black immediately.

However, in tsume-go you should always think twice before really capturing a single opponent’s stone that is in atari.

Problem O0029

＞＜

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< This problem as “Black to kill” >

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Solution

＞＜

Black 1 occupies the central point of his potential eye space, successfully dividing it into two eyes.

Black’s group is alive.

Black is the owner of the point A, so White’s -stone cannot escape capture and will become Black’s second eye.

＞＜

This sequence – starting with White 2 – is shown only for demonstrative purposes. Black captures at 3 and is alive.

In a real game, White would change the order of moves here, in order to avoid an uncalled-for loss of two points – unless she badly needed an additional forcing move in exchange.

＞＜

White has another forcing move up her sleeves, the atari at 4 – threatening to capture Black’s four stones at the right, but Black simply connects at 5, capturing White’s single stone.

In total, White has played two ko threats here, but one of which lost points.
In a real game, you will always want to think twice, whether you can afford using a locally disadvantageous ko threat.

Subvariation for White 2

＞＜

In a real game, White has the forcing move at 2 up her sleeves – threatening capture at 3 – that could be utilized in a ko fight elsewhere on the board.

Black captured only one stone here, two less than in the sequence shown above.

Shape Analysis

Black’s potential eye space consists of three points in a row (●).

The central point of the dead three-point eye shape (△, □, ) is still unoccupied.

Black’s partial group at the right has only two liberties, and so is in immanent danger of becoming captured.

Please note that one of these liberties is shared (●) with White’s strong formation on the outside (), so Black is in danger of suffering from a shortage of liberties.

White’s single stone inside Black’s formation also has only two liberties, but still some scope for action.

Black will have to find a proper way to immobilize this white stone.

Misguidance

The hole (??) in Black’s encirclement must not be closed directly.

Please note that it does not make sense to consolidate the borders of your formation – in an attempt to maximize your potential eye space – if you are leaving behind only a dead eye shape which central point is still unoccupied.

Problem O0030

＞＜

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Solution

＞＜

Black 1 occupies the central point of his potential eye space, successfully dividing it into two eyes.

Black’s group is alive.

Black is the owner of the point A, so White’s -stone cannot escape capture.

Saving Black’s three stones at the right with a black move at A or capturing these three stones with a white move at B is only an endgame issue.

＞＜

White does not have immediate forcing moves that could be utilized in a ko fight elsewhere on the board.
Even if White 2 captures Black’s three stones at the right, …

＞＜

… Black can play elsewhere with 3.
After White’s forcing move at 4, Black captures at 5, securing his second eye.

These two moves are miai.

Variation for White 4

＞＜

White’s connection at 4 here is the “tsume-go variation” which would not be played in a real game.

＞＜

Black 5 simply captures three white stones, which will be sufficient for creating an eye on the first line.

＞＜

White throws in at 6, but Black secures his second eye by capturing at 7.

Shape Analysis

Black’s potential eye space consists of three points in a row (●).

Black’s partial groups in the corner are not yet solidly connected (), leaving a grave weakness that can be exploited by White.

Black’s groups in the corner have only two or three liberties, and so are very vulnerable to an attack.

Please note that two of these liberties are shared (●). This implies that Black’s stones in the corner could easily fall prey to a shortage of liberties.

The central point of the dead three-point eye shape (△, □, ) is still unoccupied.

Misguidance

Black’s partial groups at the right are not yet solidly connected ().

However, please note that this fact does not affect the life & death status of Black’s main forces here. You will always have to distinguish between important and unimportant parts of your entire formation.

At the right, both Black’s three-stone group and White’s single stone have only one liberty, and so are in danger of becoming captured.

However, this mutual atari might be only on the board to bedazzle your mind.

In tsume go you should always think twice before really capturing a single of your opponent’s stones.

Please note that it will not affect the core structure of the problem, if these three black stones are taken off the board for demonstrative purposes.

Connecting stones that are arranged on a zigzag-line (, ✕) might fail, due to a shortage of liberties.

The formation at the right is still equivalent to a hole (??) in Black’s encirclement but which must not be closed directly.

Please remember that it does not make sense to consolidate the borders of your formation – in an attempt to maximize your potential eye space – if you are leaving behind only a dead eye shape which central point is still unoccupied.

Problem O0032

＞＜

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< This problem as “Black to kill” >

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Solution

＞＜

Black 1 occupies the central point of his potential eye space, successfully dividing it into two eyes.

Black’s group is alive.

Black must not mistakenly play at M, instead, connecting at the left.

Black is the owner of the point A, so White’s -stone cannot escape capture and will become Black’s second eye.

＞＜

White does not have immediate forcing moves that could be utilized in a ko fight elsewhere on the board.
Even if White 2 gives atari at Black’s single stone at the left, Black can play elsewhere with 3.
After White’s forcing move at 4, …

＞＜

… Black captures at 5, securing his second eye.

Failure M (one-move)

Black just connected at the left.

＞＜

White 2 occupies the central point of Black’s eye space that Black should have taken beforehand.

There is no option left for Black to partition his eye space, so his group is dead.

Shape Analysis

Black’s potential eye space consists of three points in a row (●).

The central point of the dead three-point eye shape (△, □, ) is still unoccupied.

White’s single stone inside Black’s formation has only two liberties, and so might become immobilized quite easily.

Misguidance

Black’s partial groups are not yet solidly connected (), leaving cutting points for White to exploit.

At the bottom, you can see a potential lines of false eyes (, ✕).

This formation at the left is equivalent to a defect (??) in Black’s encirclement but which must not be closed directly.

Please remember that it does not make sense to consolidate the borders of your formation – in an attempt to maximize your potential eye space – if you are leaving behind only a dead eye shape which central point is still unoccupied.

Problem O0033

＞＜

< Go to the next problem >

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< This problem as “Black to kill” >

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Solution

＞＜

Black 1 closes the hole in his encirclement, securing a living shape for his group.

Black must not mistakenly play at M, instead, capturing White’s single stone at the right, nor at N, trying to expand his potential eye space at the top.

Black is the owner of the point of A, so White’s single -stones cannot escape capture. The point of A is taboo for White, so Black will get two eyes.

＞＜

White 2, occupying one of Black’s outside liberties, is no real threat. Black is able to play elsewhere with 3.
Thereafter, White has the forcing move of 4 up her sleeves, giving atari at Black’s group. But Black simply captures at 5, successfully dividing his eye space into two eyes.

Failure M (five-move)

Black just captured White’s single stone at the right.

＞＜

White 2 wedges into the hole of Black’s formation, simultaneously giving atari at both black groups.

Please note that White occupied the point that Black should have taken beforehand.

＞＜

Black has no other choice but to capture White’s two stones at 3, but he will be unable to create a second eye for his group.

＞＜

White throws in at 4, in order to turn Black’s potential eye at the left into a false one.

Black’s -stone is in atari, but he is unable to connect at A; White would simply capture at B.

＞＜

Therefore, Black 5 captures White’s just played stone, but …

＞＜

… White gives atari at 6, and Black has only one real eye at the right.

Failure N (one-move)

Black just tried to expand his potential eye space by playing a diagonal move at the top left.

＞＜

White 2 occupies the central point of Black’s eye space, connecting her two single stones to a dead three-point eye shape.

White might consider playing at S instead. This move will also successfully kill Black’s group, but it might contain a tiny disadvantage.

＞＜

Here, Black has only one forcing move at 3 up his sleeves – capturing White’s threes stones – that could be utilized in a ko fight elsewhere on the board.

＞＜

White 4 occupies the central point of Black’s eye shape again, preventing Black from dividing his eye space.

Subvariation for White 2 = Variation S

＞＜

White 2 gives atari at all of Black’s groups.

＞＜

Black has no other choice but to capture White’s two stones at 3.

＞＜

White throws in at 4, in order to turn Black’s potential eye at the left into a false one.
Black is unable to play at A, due to his shortage of liberties; White would simply capture at 5.
Therefore, Black 5 captures White’s just played stone, but …

＞＜

… White gives atari at 6, and Black has only one real eye at the right.

Shape Analysis

Black’s potential eye space consists of three points in a row (●).

Black’s partial groups are not yet solidly connected ().

The hole (!!) in Black’s encirclement at the top needs reinforcement.

Both black partial groups have only two liberties, and so are very vulnerable to an attack.

Please note that one of these liberties is shared (●). This implies that these groups could easily fall prey to a double-atari.

White’s single stones inside Black’s formation have only one or two liberties, and so are very vulnerable to an attack.

White’s two single stones inside Black’s formation share one liberty (○), and so are handicapped by a potential shortage of liberties.

Misguidance

Black’s potential eye space can be filled with a dead three-point eye shape (, □) which central point is still unoccupied.

It is important to recognize that this shape is an invalid one here; following its fake hints will lead to failure.

White’s single stone at the right has only one liberty, and so could be captured by Black immediately.

However, in tsume-go you should always think twice before really capturing opponent’s stones that are in atari.

White’s formation at the left edge () is very strong, severely restricting Black’s further development in the neighborhood.

At the left, you can see a potential line of false eyes (, ✕).

The large hole (!!) outside Black’s encirclement at the top is not the best starting point for him.

Please note that Black is unable to occupy both marked points, due to his shortage of liberties at the left.

My books

The most difficult problem ever: Igo Hatsuyōron 120

The most difficult of all Go problems, created by Inoue Dosetsu Inseki (1646 – 1719), has still not been solved by professional Go players. The long-standing collaboration of three amateurs from Germany and the United Kingdom has now found the answer!

This book celebrates the problem-collection’s 300th anniversary and is the most comprehensive collection of information about this stunning problem. The book discusses what the authors believe to be the solution to the problem, including an in-depth treatment of the failed lines. All move sequences are explained in great detail. The same is true for the additional work on theoretical issues that are fundamental to the problem (e.g. hanezeki, approach-move liberties, and ko).

English, German
SmartGo Books, 2013
$9.99; 805 pages; 1 problem

Igo Hatsuyōron 120 – An Elephant in Slices

The most difficult of all Go problems, created by Inoue Dosetsu Inseki (1646 – 1719), has still not been solved by professional Go players.

“How do you eat an elephant?” is the usual management consultant’s reply when being asked how to manage a huge project.

This book presents this difficult problem in 120 slices. Each aspect of Igo Hatsuyōron 120 is explained using relatively simple individual problems, so you can understand the entire puzzle.

Enjoy a journey through time — look over the shoulder of Dosetsu and get a picture of how he composed his masterpiece.

SmartGo Books, 2015
$6.99; 484 pages; 121 problems

Igo Hatsuyōron 120 – Below the surface of most difficult problem ever

Igo Hatsuyōron is the most difficult of the classical books on tsume go.

This problem collection was compiled in 1713 by Dosetsu Inseki, the third head of the Inoue Go School, and was designed for the training of the highest caliber students at the school. It was kept secret from all but a few of them, who studied the book under the direct supervision of the Inoue.

183 problems (of estimated more than 1,500) have survived to modern times. Unfortunately, all others were lost in fire.

Among these the most difficult is #120, widely believed to be the most difficult Go problem ever created, which has still not been solved by professional Go players.

The long standing collaboration of three amateurs, from Germany, and the United Kingdom, has found the answer!

Get the whole story in two volumes. Over 1,100 pages in the hardcover edition!

Published in 2015.

– Our solution to the problem.
– Explains the general structure of the problem in large detail.
– Contains a large number of variations.
608 pages

Buy with Lulu.com; € 20.96 (+ tax)

Read on our website

– The professionals' solution to the problem.
– Contains all the variations that are known to us.
– Gives deep insights into the ups, and downs, of our research.
– Explains several structural elements of the problem in great detail.
496 pages

Buy with Lulu.com; € 18.72 (+ tax)

Read on our website

Tsume-Go Strategy 1 – Corner Patterns – Learn to Recognize Vital Points in Go Problems

Did you ever complain about Go problems that are much too difficult for you to solve? And probably lost courage? Inoue Dōsetsu Inseki’s advice — written down over 300 years ago — is to study shape. This book helps you do that and overcome your current weakness in the beautiful field of tsume-go.

Study over 300 problems — based on 47 corner patterns — that are analyzed in great detail. Absorb numerous hints that direct your gaze to previously unrecognized vital shape points.

This book tries a novel approach in offering an important intermediate step between the main problem diagrams and the respective solutions. Alternative approaches as well as failures are presented as separate problems to be solved individually.

This book is the predecessor of “Tsume-Go Strategy 2”, and can be studied independently.

SmartGo Books, 2015
$9.99; 1,304 pages; 314 problems

Tsume-Go Strategy 2 – Side Patterns – Learn to Recognize Vital Points in Go Problems

Have you ever complained about Go problems that are much too difficult for you to solve? And then lost courage?

Inoue Dōsetsu Inseki’s advice — written down over 300 years ago — is to study shape. This book helps you do that and overcome your current weakness in the beautiful field of tsume-go.

Study over 400 problems – based on 44 side patterns – that are analyzed in great details. Absorb numerous hints that direct your gaze to previously unrecognized vital shape points.

This book tries a novel approach in offering an important intermediate step between the main problem diagrams and the respective solutions. Alternative approaches as well as failures are presented as separate problems to be solved individually.

This volume is a successor of “Tsume-Go Strategy 1”, but it can be studied independently.

SmartGo Books, 2015
$11.99; 1,992 pages; 424 problems

Workbook: Three-Move Life and Death Problems – Basic Tsume-Go Strategy Made Easy (2)

This workbook is designed especially for players who have left the beginner’s stage and feel able to think three moves ahead. Each of the over 400 problems only requires you to think about one preparatory move, setting the scene for one successive final blow.

The problems of this collection are ordered by shape. Repetition matters, so each shape provides as many slightly different problems as possible. While each problem is explained in detail, readers can choose whether to simply continue with the next problem, or switch to the detailed explanation of the main solution, side variations, failures and the analysis of the problem’s shape issues.

Very often, side variations and refutations of failures are more complicated than the main path of the problem’s solution. While studying these additional variations — again at the reader’s own choice — the reader will be gently and subtly guided to more complicated issues in the beautiful field of tsume-go, preparing for the next step in study.

This book is a successor of “Workbook 1: One-Move Life and Death Problems”, but can be studied independently.

SmartGo Books, Publication date: Autumn 2017
$9.99; 2,000 pages; 400 problems

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© Copyright 2016 by Thomas Redecker

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