A ko is when you can take and take back forever.

_________________
The Adkins Principle:
At some point, doesn't thinking have to go on?
— Winona Adkins

Visualize whirled peas.

Everything with love. Stay safe.

What if the ko rule is simply "do not recreate a previous position"?

Does that really cause seemingly unjust outcomes?

Playing on an actual board, the farther away you get from traditional ko to various types of superko and other repeating positions, the harder it is to remember when you are obligated to break the cycle and when you can play through it.

Sure, but how likely is it really that you become stuck in, say, a 30-move repeating cycle?

Most of the infinite loops I've seen were under 10 moves, with the vast majority being about a simple ko.

It doesn't seem like something that's realistically a factor for amateur play, and pros would most definitely notice.

Great. I hope you can recall and share it. Already your quadruple ko stones have been a tough exercise.



Apply the definition to detect any kos in a given situation.

I think I have it in my bookshelf.

Matti

Case number 1:

Click Here To Show Diagram Code

[go]$$B 1.A simple ko situation
$$ +-------------------+
$$ | . . . . . . . . . |
$$ | . . . . . . . . . |
$$ | . . , . . . , . . |
$$ | . . . . . . . . . |
$$ | . . . . , . . . . |
$$ | X X X X . . . . . |
$$ | O O O X X . , . . |
$$ | . O . O X X . . . |
$$ | . O O . O X . . . |
$$ +-------------------+[/go]

Click Here To Show Diagram Code

[go]$$B 2.ko is taken
$$ +-------------------+
$$ | . . . . . . . . . |
$$ | . . . . . . . . . |
$$ | . . , . . . , . . |
$$ | . . . . . . . . . |
$$ | . . . . , . . . . |
$$ | X X X X . . . . . |
$$ | O O O X X . , . . |
$$ | . O . O X X . . . |
$$ | . O O 1 . X . . . |
$$ +-------------------+[/go]

Obviously, retaking now cannot happen under my rule, because an earlier position would be revisited.

Click Here To Show Diagram Code

[go]$$B 3.ko is retaken
$$ +-------------------+
$$ | . . . . . . . . . |
$$ | . . . . . . . . . |
$$ | . . , . . . 2 . . |
$$ | . . . . . . 3 . . |
$$ | . . . . , . . . . |
$$ | X X X X . . . . . |
$$ | O O O X X . , . . |
$$ | . O . O X X . . . |
$$ | . O O . 4 X . . . |
$$ +-------------------+[/go]

Playing some stones elsewhere allows it to be retaken, because this position is not the same as diagram 1.
That takes care of the simplest case.

Case number 2:

Click Here To Show Diagram Code

[go]$$B 4.seki
$$ +-------------------+
$$ | X O X . X . X . O |
$$ | X O X X X X O O . |
$$ | X O O O O O O O O |
$$ | X X X X X X X X X |
$$ | . . . . , . . . . |
$$ | . . . . . . . . . |
$$ | . . , . . . , . . |
$$ | . . . . . . . . . |
$$ | . . . . . . . . . |
$$ +-------------------+[/go]

Click Here To Show Diagram Code

[go]$$B 5.
$$ +-------------------+
$$ | X O X . X . X 1 O |
$$ | X O X X X X O O . |
$$ | X O O O O O O O O |
$$ | X X X X X X X X X |
$$ | . . . . , . . . . |
$$ | . . . . . . . . . |
$$ | . . , . . . , . . |
$$ | . . . . . . . . . |
$$ | . . . . . . . . . |
$$ +-------------------+[/go]

this is just silly in real life, but we're in theory here.

Click Here To Show Diagram Code

[go]$$B 6.
$$ +-------------------+
$$ | X O X . X 2 a . O |
$$ | X O X X X X O O . |
$$ | X O O O O O O O O |
$$ | X X X X X X X X X |
$$ | . . . . , . . . . |
$$ | . . . . . . . . . |
$$ | . . , . . . , . . |
$$ | . . . . . . . . . |
$$ | . . . . . . . . . |
$$ +-------------------+[/go]

Black cannot play at a, because that recreates diagram 4.

Click Here To Show Diagram Code

[go]$$B 7.
$$ +-------------------+
$$ | X O X . X 2 5 . O |
$$ | X O X X X X O O . |
$$ | X O O O O O O O O |
$$ | X X X X X X X X X |
$$ | . . . . , . . . . |
$$ | . . . . . . . . . |
$$ | . . , . . . 3 4 . |
$$ | . . . . . . . . . |
$$ | . . . . . . . . . |
$$ +-------------------+[/go]

Black can play 5, because diagram 4 is not recreated.

I explicitly refuse to consider including things like how many captures there are, whose turn it is or other game state data which you cannot see expressed on the board's intersections.
I think adding such details just makes my idea overcomplicated and unfit for purpose.

That also means there are no special cases which need special descriptions. I would like to see some complicated cases, where my idea actually affects the outcome.

Especially if the changed outcome is perceived as less fair somehow.

tentano, all fine and well, but what is the point of your discussion of positional superko here? Do you want to express any relation to the topic of this thread, or do you just share my preference for this rule when used as a rule in an ordinary ruleset?

Hm, I don't know what I initially intended, but it looks like we're purely in agreement about which rule is the best, then.

OK, let's continue your second example.

Click Here To Show Diagram Code

[go]$$B 8.
$$ +-------------------+
$$ | X O X . X . X 7 O |
$$ | X O X X X X O O . |
$$ | X O O O O O O O O |
$$ | X X X X X X X X X |
$$ | . . . . , . . . . |
$$ | . . . . . . . . . |
$$ | . . , . . . B W . |
$$ | . . . . . . . . . |
$$ | . . . . . . . . . |
$$ +-------------------+[/go]

and indicate "ko" threat and reply.

= pass

Now White cannot capture, because that would recreate the position after in diagram B 7.

Many, if not most, go players regard that as a problem.

_________________
The Adkins Principle:
At some point, doesn't thinking have to go on?
— Winona Adkins

Visualize whirled peas.

Everything with love. Stay safe.

Assuming that white is somehow forced to pass, how is it unfair that black wins the ko?

Isn't it by that very same logic unfair that black is forced to endure a seki or a loss under other rules?

As far as I know fairness doesn't naturally accumulate to either colour.

What is the problem that is being regarded, here?

Basically, I think, the problem is that the corner position is regarded as a seki, not a ko. If the rules turn it into a ko, that is a problem.

To put it another way, the rules are meant to serve the players, not the players the rules.

_________________
The Adkins Principle:
At some point, doesn't thinking have to go on?
— Winona Adkins

Visualize whirled peas.

Everything with love. Stay safe.