What's wrong with suicide?

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Jordus
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Re: What's wrong with suicide?

Post by Jordus »

Suicide is just a bad move (i.e. the name suicide....), because you can not benefit whatsoever from it. In fact you are hurt by it. You give your opponent an extra point, and it is their move.
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Re: What's wrong with suicide?

Post by oren »

Jordus wrote:Suicide is just a bad move (i.e. the name suicide....), because you can not benefit whatsoever from it. In fact you are hurt by it. You give your opponent an extra point, and it is their move.


There is a possibility you can use it as a ko threat. There are also times when you may consider doing it for extra time if it makes an answer required.
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Re: What's wrong with suicide?

Post by Jordus »

oren wrote:
Jordus wrote:Suicide is just a bad move (i.e. the name suicide....), because you can not benefit whatsoever from it. In fact you are hurt by it. You give your opponent an extra point, and it is their move.


There is a possibility you can use it as a ko threat. There are also times when you may consider doing it for extra time if it makes an answer required.


How can it be used as a ko threat? Using Araban's diagram:

Click Here To Show Diagram Code
[go]$$Wc Playing at T19 as White
$$ ------------------
$$ . . . . . . X O 2 |
$$ . . . . . . X X O |
$$ . . . . . . . X X |
$$ . . . . . , . . . |
$$ . . . . . . . . . |
$$ . . . . . . . . . |[/go]


if white plays suicide, all three stones are now gone and its black turn. black plays :b2: . Now white is in the position as before. Ko threat = 0.

*edit* unless..... you were talking about it as a threat in order to take another ko on the board.... hmmmmmm :-?
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Re: What's wrong with suicide?

Post by amnal »

Jordus wrote:
oren wrote:
Jordus wrote:Suicide is just a bad move (i.e. the name suicide....), because you can not benefit whatsoever from it. In fact you are hurt by it. You give your opponent an extra point, and it is their move.


There is a possibility you can use it as a ko threat. There are also times when you may consider doing it for extra time if it makes an answer required.


How can it be used as a ko threat? Using Araban's diagram:

Click Here To Show Diagram Code
[go]$$Wc Playing at T19 as White
$$ ------------------
$$ . . . . . . X O 2 |
$$ . . . . . . X X O |
$$ . . . . . . . X X |
$$ . . . . . , . . . |
$$ . . . . . . . . . |
$$ . . . . . . . . . |[/go]


if white plays suicide, all three stones are now gone and its black turn. black plays :b2: . Now white is in the position as before. Ko threat = 0.


Remember, a ko threat is a move which your opponent answers. Since black answered (in order to keep his two eyes), that *was* a ko threat. Ko threat = 1.
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Re: What's wrong with suicide?

Post by Jordus »

Jordus wrote:
oren wrote:
Jordus wrote:
*edit* unless..... you were talking about it as a threat in order to take another ko on the board.... hmmmmmm :-?


amnal wrote:Remember, a ko threat is a move which your opponent answers. Since black answered (in order to keep his two eyes), that *was* a ko threat. Ko threat = 1.


Good thing its against the rules then.....

*edit* My bad... quote#2 was from amnal not oren... sorry amnal..... :oops:
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Re: What's wrong with suicide?

Post by oren »

Jordus, you attributed quote to wrong person. :)
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Re: What's wrong with suicide?

Post by palapiku »

Harleqin wrote:
DrStraw wrote:There is a rule which says that stones cannot be on the board if they have no liberties. An obvious consequence of this is that you cannot make a move which results in no liberties. Suicide is logically not possible.


No, the obvious consequence is that if you play a stone which has no liberties, it is removed. Suicide is thus logically possible.

A play is

  • placing a stone on an empty intersection, then
  • removing all opposing stones that have no liberties, if any, then
  • removing all own stones that now still have no liberties, if any.


I agree with DrStraw. Suicide is logically impossible because a group can't have zero liberties. It's that simple.

Your description of what a play is doesn't describe Go the way it is normally played (though it does sound a lot like New Zealand rules).
The way Go is usually played is actually more simple. A play is

  • placing a stone on an empty intersection, then
  • removing all opposing stones that have no liberties, if any.

"Removing all own stones" is not a step in the traditional game of Go. It is something New Zealand rules introduced for the sake of being cute and simple. It is a clever trick, and I admire its cleverness. But I don't like it. It reminds me of those mathematical proofs where instead of doing three obvious steps you do one step which makes no sense, yet, by magic, everything simplifies and the problem is solved. Such proofs are cute but not helpful.
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Re: What's wrong with suicide?

Post by Harleqin »

palapiku wrote:
Harleqin wrote:
DrStraw wrote:There is a rule which says that stones cannot be on the board if they have no liberties. An obvious consequence of this is that you cannot make a move which results in no liberties. Suicide is logically not possible.


No, the obvious consequence is that if you play a stone which has no liberties, it is removed. Suicide is thus logically possible.

A play is

  • placing a stone on an empty intersection, then
  • removing all opposing stones that have no liberties, if any, then
  • removing all own stones that now still have no liberties, if any.


I agree with DrStraw. Suicide is logically impossible because a group can't have zero liberties. It's that simple.

Your description of what a play is doesn't describe Go the way it is normally played (though it does sound a lot like New Zealand rules).
The way Go is usually played is actually more simple. A play is

  • placing a stone on an empty intersection, then
  • removing all opposing stones that have no liberties, if any.

"Removing all own stones" is not a step in the traditional game of Go. It is something New Zealand rules introduced for the sake of being cute and simple. It is a clever trick, and I admire its cleverness. But I don't like it. It reminds me of those mathematical proofs where instead of doing three obvious steps you do one step which makes no sense, yet, by magic, everything simplifies and the problem is solved. Such proofs are cute but not helpful.


You forgot the third step when suicide is forbidden: backtracking. A play then is

  • placing a stone on an empty intersection, then
  • removing all opposing stones that have no liberties, if any, but
  • not allowed if there would now be any own stones that have no liberties (you have to choose a different intersection initially).

Tradition is not the only source of go rules. Traditional rules have evolved, and they have changed in sometimes surprising ways. There was a different perception of how the rules work in the 19th century than in the beginning of the 20th century, and in turn different than in the middle of the 20th century and even in turn than in the end of the 20th century. There were times when people actually thought a moonshine ko could be alive. The Go rules are not invented, but discovered, and tradition is not adoration of the ashes, but passing on the fire.
A good system naturally covers all corner cases without further effort.
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Re: What's wrong with suicide?

Post by palapiku »

There's no "backtracking" because that's actually the zeroth step - you verify the legality of your move before you make it. Verifying that a move is legal before making it is a natural part of the game (allowing suicide doesn't get rid of this step). Taking off your own stones is not. You'd have to stretch across the whole board to drop them into the opponent's lid!
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Re: What's wrong with suicide?

Post by DrStraw »

Harleqin wrote:
DrStraw wrote:There is a rule which says that stones cannot be on the board if they have no liberties. An obvious consequence of this is that you cannot make a move which results in no liberties. Suicide is logically not possible.


No, the obvious consequence is that if you play a stone which has no liberties, it is removed. Suicide is thus logically possible.

A play is

  • placing a stone on an empty intersection, then
  • removing all opposing stones that have no liberties, if any, then
  • removing all own stones that now still have no liberties, if any.


When you remove the opponent's stone you gain them as captured stones, which count in your favor at the end of the game. If you remove your own stones what happens to them? You are the one who removed them not the opponent. So you have two options:

1) Stones with no liberties are removed, sometimes going to the person doing the removing and at other times going to the opponent of the one doing the removing.
2) Stones with no liberties are removed, sometimes being removed by the person making the move and at other times by the opponent of the one making the move.

Neither option is elegant. Go is all about elegance. Inelegant rules such as these have no place.
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Re: What's wrong with suicide?

Post by Harleqin »

Which lid I put the stones in should really make no difference in "elegance". Besides, suicide is in all but very rare situations just a bad move, so in the event of a player playing such a move, unusual motions are appropriate.

I think that forbidding suicide is just a needless restriction, even if most of the time that restriction only prevents bad moves.
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Re: What's wrong with suicide?

Post by amnal »

Harleqin wrote:Which lid I put the stones in should really make no difference in "elegance". Besides, suicide is in all but very rare situations just a bad move, so in the event of a player playing such a move, unusual motions are appropriate.

I think that forbidding suicide is just a needless restriction, even if most of the time that restriction only prevents bad moves.


Elegance is a rather subjective term, I can completely understand people considering suicide inelegant. I suppose I consider it that way myself.

I'm well aware that there are perfectly good rulesets allowing suicide, but its forbidding is not a 'needless restriction' to me. Since there is no obvious reason to allow or disallow it (other than perhaps this subjective 'elegance' which I agree with), it's just a choice whether to allow it or not. A set of rules to allow a player to capture his own stones is a needless addition just as much as disallowing this act is a needless restriction. But you have to choose one, as a necessary clarification.
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Re: What's wrong with suicide?

Post by Harleqin »

If we come from a different way, the two choices present themselves like this:

Axiom: There can never be stones without liberties on the board.

No suicide: If a play of one player causes stones of the opposing player to be without liberty, those stones are removed. If a play of one player would cause only own stones to be without liberty, that move is illegal.

Suicide: If a play causes stones to be without liberty, they are removed. Removing opposing stones takes precedence.
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Re: What's wrong with suicide?

Post by Bill Spight »

Harleqin wrote:If we come from a different way, the two choices present themselves like this:

Axiom: There can never be stones without liberties on the board.

No suicide: If a play of one player causes stones of the opposing player to be without liberty, those stones are removed. If a play of one player would cause only own stones to be without liberty, that move is illegal.

Suicide: If a play causes stones to be without liberty, they are removed. Removing opposing stones takes precedence.


How about this?

Axiom: After a play there can never be a stone without a liberty on the board.

No suicide: If placing a stone on a point causes an opposing stone to have no liberty, all such stones are removed.

Suicide: If placing as stone on a point causes a stone to have no liberty, all such opposing stones are removed. After that, all stones without a liberty are removed.

----

I think that rules that allow suicide are more complex than rules that do not. :)
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Re: What's wrong with suicide?

Post by judicata »

This is a fascinating debate (and a civil one at that).

I think both sides have some good points, and I'd really like to see a group of professionals (say 5-9) from different countries opine.
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