Living shapes & dead shapes (2)
1. A group having 5 liberties is not always alive, it depends on the shape of that liberties. Here we have a living shape and I hope you can figure out how black can resist any attack.
2. This shape is alive too, same as above.
3. Here we have a problem...
4. If white plays first he can kill black starting at 1.
5. If black ignores white 1 in the diagram before, he is dead and this can be proved (but not necessary to be played in a real game!) as in this diagram: white can play 3 more stones (as in this diagram) and black's group is left with one liberty. Even if black captures 4 white stones, he can't make life in the new shape (see the 4 liberties chapter).
6. If black to move,he can make life by playing at 1 (A and B are also possible)
7.This is another shape of 5 not living if white to move.
8. White 1 here is killing, black is having no counter to this.
9. If white adds 3 more stones as shown here (once again this is not necessary in a real game), black is left with one liberty but even if he captures 4 stones he is dead in the new shape.
10. If black to play, this move gives him 4 eyes, so he is alive...
11. Shapes with 6 liberties are not always safe, as we will see. This one is alive.
12. If white 1, black plays 2, and now either A or B is giving black 2 eyes, so white can't do anything.
13. This shape instead is not that safe...
14. White 1 is killing...
15. Black 2 here is not working...
16. Again, if black plays first, he can make life like this.
17.The shapes of 7 liberties are always alive and this is the only one with some problems.
18. White 1 here leads to a seki, so black is alive but no points. White can't play A or B (black will capture 4 stones and the shape will be a living one)
19. Black can even ignore first white move. If white continue to play here, the position will end up in seki again...
20. This group is having also 7 liberties but his eye-space can be reduced.
21. This sequence leads to black's death. Black A and B are not helping, the resulting eyes will be fake.
22. White must be careful when attacking as this sequence leads to a seki, so black is alive.
23. If black to move, this is one way he can live. We must be very careful when building a shape for eyes, always avoiding the dead shapes. Next we have a better example.
24. What about this one?
25. Trying to get the largest eye-space is bad, as white 2 is the vital point and black will die.
26. Black must play first move as shown here. If white 2 he can play 3 and get 2 eyes. If white 2 at 3, then black can play 2 himself and it's still alive. Sometimes we must be satisfied with a small life...
 
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