Extending from an enclosure

  Difficulty: Beginner   Keywords: Opening

Table of contents Table of diagrams
Extensions from an enclosure
Choice of direction
Box shaped spheres of influence
Preventing an extension
Ideal for both

Introduction

[Diagram]
Extensions from an enclosure  

B1 is an extension from a small high enclosure. W2 extends from a small low enclosure. B3 is an extension from a large low enclosure, forced to a shorter distance by W2. W4 makes a double wing formation and B5 prevents the extension of the enclosure in the lower right.

What is the best direction to extend?

[Diagram]
Choice of direction  

Black here can extend from his corner enclosure towards either a or b (or the points around them). In general, without any neighbouring stones influencing the choice, it is best to extend along the high side of the enclosure. Along the left side, the enclosure sends its influence up to the fifth line. Along the top, the influence only reaches the fourth line. The more box-shaped the sphere of influence Black creates here, the more efficiently his stones are distributed.

[Diagram]
Box shaped spheres of influence  

Compare the Black and White positions. Although White creates a stable position, her stability is considered to be outweighed by the scale of Black's development.

Extensions preventing extensions

[Diagram]
Preventing an extension  

a would be ideal development for White's enclosure. So, B1 prevents it. The choice for B1 instead of a has a more subtle reason.

[Diagram]
Ideal for both  

In this case, a is the ideal development for both upper left and lower left enclosure. b and c would be good development for one and negative for the other. d would be negative for both. Obviously, Black will play a here before the other three.

Exceptions to these guidelines

(examples to be added)


Extending from an enclosure last edited by 130.184.196.251 on October 9, 2006 - 20:08
RecentChanges · StartingPoints · About
Edit page ·Search · Related · Page info · Latest diff
[Welcome to Sensei's Library!]
RecentChanges
StartingPoints
About
RandomPage
Search position
Page history
Latest page diff
Partner sites:
Go Teaching Ladder
Goproblems.com
Login / Prefs
Tools
Sensei's Library