Unsettled - Introductory

   

Sometimes stones will be Alive or Dead based on who plays first. Such stones are called unsettled. Look at this shape:

[Diagram]
Straight 3  

This is the simplest unsettled shape[1], called the straight three. If black plays here first, the white stones will die.

[Diagram]
Straight 3  

This makes one large eye, not enough for white to live.

[Diagram]
Straight 3  

If white plays inside, black can capture immediately.

[Diagram]
Straight 3 (W2 elsewhere)  

If white doesn't want to play inside, black can play inside. White can capture the two inside stones:

[Diagram]
Straight 3 result  

This shape is dead. It's discussed in Dead - Introductory.

[Diagram]
Straight 3  

So we come to the conclusion that this shape is dead after black plays here first. But what about when white plays?

[Diagram]
Straight 3  

This shape is clearly alive with two eyes.

[Diagram]
Straight 3  

For the same reason, the bent three is also unsettled: The vital point is at a. Try to see why.



[1]There are other candidates for the simplest unsettled shape:

[Diagram]
Make another eye  
[Diagram]
Make another eye  

Unsettled - Introductory last edited by 90.196.114.60 on June 20, 2019 - 14:39
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