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Chapter One Table Shapes

1.1 Three strong shapes

This chapter introduces a number of strong shapes. Strong shape isn’t the only kind of good shape, but this is a place to start.

(Left) The basic table shape. (Centre) The double table, a perfect eye shape, and made up of two superposed table shapes, the second one marked. (Right) The bamboo joint, differing from the table shape only as marked.

(Left) When White plays 2 here, the White group develops perfect shape. (Right) If White’s strategy requires subsequent plays pushing in the centre, they are easy to find, and the marked stone is exactly placed.

1.2 Building tables

Black builds a table shape. (Left) Black’s one-point jump emerges reinforced. (Right) Now White is likely to occupy the key point for eyes.

(Left) Black plays the firm bamboo joint shape with 5, to prevent White connecting along the edge. (Right) Without the White stone on the side, Black might instead play this way. The cutting point at A remains, Black 5 works to take one liberty off White’s two-stone chain, and Black has the chance of making an eye with a play at B.

(Left) Because White has bad shape Black 1 here is hard to answer. White cannot prosper in this fight. Therefore the cutting point needs immediate defence. (Right) In some cases Black can even set up an obstinate ko.

In contrast consider what may happen if Black plays 3 as here. If White continues by sacrificing one stone (right), Black’s result is a failure from the point of view of shape – the marked Black stone is doing little work, it is much too close to a Black group that is now strong. Efficiency is a major factor in go.

In other circumstances Black may choose a different plan (left). The intention is to sacrifice one stone (right). In that diagram White 8 connects below 4. After Black 9 the Black group has developed good shape in the centre; and the earlier exchange of the two marked stones clearly favours Black. The single stone capture with 4 and 6 is a famous shape (see box below).

The ponnuki

This strong shape, resulting from the capture of a single stone in the centre of the board, is called ponnuki. There is a proverb saying ponnuki is worth thirty points.

Roughly speaking, that means the three White plays (net – Black has had a stone captured) making up the shape each have value ten points. This is normal for plays in the middle of the game. But if the ponnuki is confined, as in the example shown immediately above, its influence is less, and its value also.

When it occurs in the centre of the board, a ponnuki may have considerable influence.

{{Dia 35}}

This is a common position in which it may be a good exchange for White to make a ponnuki, at the cost of many points in the corner. The full value of White 2 and 4 will be seen in the middlegame fighting.

{{Dia 36}} {{Dia 37}}

Here, after a 3-3 invasion, it should be better for White to make the capture of the single stone in the left-hand diagram, even though Black then recaptures the corner. The White group formed by the ponnuki is quite robust: it has good eye shape already, and White probably doesn’t need to add a stone to it immediately.

In the right-hand diagram White takes the corner, but Black has good outside influence. When Black captures with 6 it is a matter of taking off a stone caught in a ladder, before a ladderbreaker is played. It also forms a ponnuki shape. Black has a cutting point, but otherwise thick shape useful in fighting.

The value of 30 points put on a ponnuki by the proverb must be qualified, as we have seen, when it is prevented from exerting full influence; but also when too close to other influence.

1.3 The wedge weakness

The table shape is sometimes worse than the bamboo joint would be, with a wedge weakness. In this case Black is powerless when White wedges in at the key point 1. There is no way to cover all three cuts A, B and C.

A related shape is often seen seen in a loose ladder tactic. White can capture Black. The placement 1 is on the point corresponding to the wedge weakness.

Suppose White misses the chance of the loose ladder, and crawls out at 1 instead. Black should now make a bamboo joint (left). The weakness of the table shape against White 5 is evident (right). The weak point at 5 has remained: it is just the method to exploit it that changes (White 3 at 5 is good shape but doesn’t capture Black’s cutting stones).

1.4 The high table

We call this more extended shape (left) the high table. (Right) White 4 makes good shape for the stones running out into the centre.

The high table may need a modification, to improve its strength from the side. When White wants to emphasise the top side, this is a good way (left). (Right) Playing 1 this way means Black 2 can expose some weak points.

(Left) Here Black gets into trouble as soon as White plays the key point 6. (Right) When a two-stone wall in the centre is developed, the two-point jump demands more foresight than the one-point jump. (Upper) After White 2 Black may find it necessary to reinforce, with a play like A or B. (Lower) If Black jumps only to 1 here, either of 2 or 3 next makes good shape.

1.5 Beyond table shapes

Here Black can jump out, rather than complete the table shape at A, regarding the exchange of the two marked stones as pure gain. (Right) This sequence (White 9 connects), emphasising the capture of stones, is dreadful for White.

(Left) With 1, inducing 2, and then 3 rather than A, White makes a lighter shape. (Right) Black continues to attack at the key point, but White is ready to sacrifice all the marked stones, for outer strength.

In this case White 1 moves out more quickly into the centre than A. (Right) Black cannot gain by an immediate cut. There is a small gain in captures, but a large loss to come at the top.

The common theme here is light play, sacrificing when it is appropriate, rather than the solid virtues of the table shape.

Chapter One Table Shapes#

1.1 Three strong shapes#

1.2 Building tables#

The ponnuki#

1.3 The wedge weakness#

1.4 The high table#

1.5 Beyond table shapes#