The nearly minimal problem

[fanfan]

Hello,

For many (many) years, i ask beginners to solve the following problem, that I call "the nearly minimal problem": on an empty goban, Black plays at the 1-1 point, then White tries to make a living group with a white stone on the 1-1 (the word "with" is important).

$$B
$$ ------------
$$ | 1 . . . . .
$$ | . . . . . .
$$ | . . . . . .
$$ | . . . . . .
$$ | . . . . . .
$$ | . . . . . .

Click Here To Show Diagram Code

[go]$$B
$$ ------------
$$ | 1 . . . . .
$$ | . . . . . .
$$ | . . . . . .
$$ | . . . . . .
$$ | . . . . . .
$$ | . . . . . .[/go]

Easy?

[EdLee]

Hi fanfan, Does B resist or pass forever when W moves each time ?

If B passes forever after :

$$B :w10: at :b1:
$$ --------------
$$ | 1 O . O . O .
$$ | O O O O O O .
$$ | . . . . . . .
$$ | . . . . . . .

Click Here To Show Diagram Code

[go]$$B :w10: at :b1:
$$ --------------
$$ | 1 O . O . O .
$$ | O O O O O O .
$$ | . . . . . . .
$$ | . . . . . . .[/go]

[fanfan]

Of course, Black replies and tries to kill White.

[EdLee]

Of course, Black replies and tries to kill White.

Thanks for clarifying. The "of course" part was not obvious, since for raw beginners, we sometimes "pass forever" to teach them some things.

If B resists, it's not obvious to me this can be done, nor does this appear to be a problem for raw beginners.

Just to be very clear, when you say beginners, do you mean they know only the most basic rules ? Do they "know" about ladders ? Do they "know" about real eyes and false eyes ? Please clarify.

[fanfan]

Hello,

I ask beginners to solve this problem just to train them. But you are right : this is a difficult problem.

Here, my aim is to determine who will win the figth since I am not sure myself to be able to solve this problem.

[EdLee]

I am not sure myself to be able to solve this problem.

Hi fanfan, I feel it's important and fair to warn the "beginners" you don't know if this problem has a solution.

Also, I don't think this is appropriate for raw beginners.

[MMaestro]

When I was running my club before, I used to have a friend who would teach beginners in a similar way, except he would play on the 2-1 point, not the 1-1. I think for the 1-1 point, white can simply play the 2-2 point and keep extending each time black pushes. But for the 2-1 point, the shoulderhit is more difficult because black's pushes actually gain eyespace

[Bill Spight]

Hello,

For many (many) years, i ask beginners to solve the following problem, that I call "the nearly minimal problem": on an empty goban, Black plays at the 1-1 point, then White tries to make a living group with a white stone on the 1-1 (the word "with" is important).

$$B
$$ ------------
$$ | 1 . . . . .
$$ | . . . . . .
$$ | . . . . . .
$$ | . . . . . .
$$ | . . . . . .
$$ | . . . . . .

Click Here To Show Diagram Code

[go]$$B
$$ ------------
$$ | 1 . . . . .
$$ | . . . . . .
$$ | . . . . . .
$$ | . . . . . .
$$ | . . . . . .
$$ | . . . . . .[/go]

Why?

[fanfan]

... for the 1-1 point, white can simply play the 2-2 point and keep extending each time black pushes...

If White plays on the 2-2 point, Black plays at the 3-3 point, and it is not obvious that White can take the 1-1 and play at the 1-1 later without dying. For instance:

$$B
$$ ------------
$$ | 1 6 . . . .
$$ | . 2 5 . . .
$$ | . 4 3 . . .
$$ | . 7 . . . .
$$ | . . . . . .
$$ | . . . . . .

Click Here To Show Diagram Code

[go]$$B
$$ ------------
$$ | 1 6 . . . .
$$ | . 2 5 . . .
$$ | . 4 3 . . .
$$ | . 7 . . . .
$$ | . . . . . .
$$ | . . . . . .[/go]

[fanfan]

Why?

This is just a problem that could be of some interest.

[Uberdude]

I could just about understand you posing that problem to teach Batoo, the Korean baduk variant that adds Starcraft-style visuals and bonus points for occupying certain squares, but what's the point for Go? Do you find it engages and encourages beginners, teaching them useful Go skills? Because I'm a 4d so pretty good at Go compared to a beginner but after my initial "WTF?!" struggle with that problem.

I think this is a better minimal problem for beginners:

$$B Black to play and capture a stone
$$ ------------
$$ | . . . . . .
$$ | . . . . . .
$$ | . . . X . .
$$ | . . X O . .
$$ | . . . X . .
$$ | . . . . . .

Click Here To Show Diagram Code

[go]$$B Black to play and capture a stone
$$ ------------
$$ | . . . . . .
$$ | . . . . . .
$$ | . . . X . .
$$ | . . X O . .
$$ | . . . X . .
$$ | . . . . . .[/go]

[fanfan]

Do you find it engages and encourages beginners...

Forget the word "Beginners". I used the term just to introduce the problem. I agree that it is not the first thing to show to a beginner.

[PeterN]

My first instinct on looking at this was to laugh and think it was easy... then I thought about it a bit more and went .

I'm suspecting this may be a situation where the only winning move is not to play (or tenuki at least).

And yes I know that completely avoids the question.

PeterN

[Charlie]

Er... I still don't get it. For instance, the problem doesn't say that you have to capture the black stone, only make a living group that happens to have a stone at 1-1. I'm fairly certain white can make life after this ...

$$B
$$ ------------
$$ | 1 . . . . .
$$ | . 2 5 . . .
$$ | . 4 3 . . .
$$ | . . 6 . . .
$$ | . . . . . .
$$ | . . . . . .

Click Here To Show Diagram Code

[go]$$B
$$ ------------
$$ | 1 . . . . .
$$ | . 2 5 . . .
$$ | . 4 3 . . .
$$ | . . 6 . . .
$$ | . . . . . .
$$ | . . . . . .[/go]

[oca]

that's a fail so far for me