All you need to know about Carpenter's Square - 14

Diagram 14.1: White to play

We now move on to shapes with the 4-4 points occupied by white. These are much weakened shapes.

Diagram 14.2: Even weaker shape

We will not discuss this even weaker shape as black is clearly dead.

Diagram 14.3: Solution 1

White 3 is simple and effective. Black clearly has insufficient eyespace. If Black 4 plays 'a', white still replies at White 5 to win the capturing race.

Diagram 14.4: Solution 2

White 3 works too. The marked stone White square forces black to fill his own eyespace at Black 6 so the whole corner is dead.

Diagram 14.5: Extra hane

If black has the extra Black square stone, white can still use Diagram 14.4 to kill the corner. This diagram shows how white would respond to Black 2 from the other side. White 5 is good. Black cannot play 'a' because of insufficient eyespace. If black plays Black 6 and *b8*, white wins the capturing race by one liberty.

Diagram 14.6: Extra liberty

Even if black has an extra liberty at 'a', white can continue to use Diagram 14.4. In case black plays *b2*, white can make it a 'Golden Chicken Standing on One Leg' to kill the corner as shown here.

Conclusion: this corner shape is too weak to survive even with either of the two favorable conditions.