Life In 19x19

gowan wrote: So in either case, White lives. In one case White gets points, in the other no points, but White lives in both cases.

I wouldn't have thought about this, since I was still looking at the problem from the point where black dies or not, not considering the fact that white remains alive.

Well...
$$B Seki
$$ -------------------
$$ | . X X X . 2 1 X .
$$ | O O O O O O O X .
$$ | . O . X X X X X .
$$ | X O O . X . . . .
$$ | X O X X X . . . .
$$ | . X . . . . . . .
$$ | . X . X . . . . .
$$ | . . . . . . . . .
In this diagram, black's three stones are also surrounded, but they're ...

skydyr wrote:

paullik wrote: Since they are inside white's territory, right?

Yes, in a sense, but do you understand why it's white's territory now and not before?

Because it's only now that the are surrounded.

One more point about this position.

$$W
$$ -------------------
$$ | . B B B . . 1 X .
$$ | O O O O O O O X .
$$ | . O . X X X X X .
$$ | X O O . X . . . .
$$ | X O X X X . . . .
$$ | . X . . . . . . .
$$ | . X . X . . . . .
$$ | . . . . . . . . .

If White plays :w1: the :bc: stones are dead ...

well then... let's play it out...

[...]

However, if White responds to the threat, white is alive in seki.
$$B Seki
$$ -------------------
$$ | . X X X . 2 1 X .
$$ | O O O O O O O X .
$$ | . O . X X X X X .
$$ | X O O . X . . . .
$$ | X O X X X . . . .
$$ | . X . . . . . . .
$$ | . X . X ...

I cannot see it...

I was reading about ko, and ko threats at Sensei's Library and I found this diagram:

http://senseis.xmp.net/diagrams/29/590ba6809839920139e10e516ac04d31.png

If I take it in isolation and consider this paragraph:
In this diagram black can play at a. White must respond at b. If white neglects to ...

Can you see that :b55: at D9 also "threatens to save the two stones ( :b31: :b29: ) " ? :)


Well, yes, it's about the territory, not about really saving them.


Things are hopefully a little clearer now than at post 5. :mrgreen:


Hopefully.


Thank you for taking the time to guide me!

EdLee wrote:Hi Paul,

paullik wrote: A5
D9
C9
F9

OK.

wrong. Some kind of blind spot.

Oh...

E9

EdLee wrote:

paullik wrote:In the original diagram:
should play at F9... then at C9...
...now I think both should pass...

at F9 is correct.
But at C9 is wrong.
Pass is also wrong.
Try again.

For the original:

F9
D9
A5
B6

EdLee wrote:

paullik wrote:if playes D9, should play at B9... at C9...

No.

A5.
D9.
Your and are wrong. Try again.

Ok, I got some time, so:

A5
D9
C9
F9

When you said "It's clear now" actually it's not what you think. :)
Well I've been playing this game for a week now and I just finished that interactive tutorial, meanwhile I've got defeated by the GoDroid application on my smartphone, but I enjoy the game!


I will try to come up with two new ...

Hmm, if :b55: playes D9, :w56: should play at B9 in order to make a border for his upper left territory and then, :b57: at C9 to get a hold of that neutral teritorry.

In the original diagram:

:b55: should play at F9 in order to capture :w22: and :w26:, then :w56: at C9 to get :b31: and :b29:, now ...

Hello EdLee,

Well, I'd say B should play at D9, in order to clearly create a border for the upper-right territory and also gain some influence in the upper left part of the board, where it seems that white is (kind of) in control.

Am I right?

It's clear now.
Thank you!