Is this L&D scenario seki?

If you're new to the game and have questions, post them here.
Milkman
Dies in gote
Posts: 24
Joined: Sun Dec 22, 2013 3:08 pm
Rank: KGS 15k
GD Posts: 0
KGS: Milkman
DGS: Milkman
Universal go server handle: Milkman
Has thanked: 16 times
Been thanked: 1 time

Is this L&D scenario seki?

Post by Milkman »

Problem life and death #21 beginner, on Hactar Go. After move 5, it says solved, but isn't it just seki? I understand, that's a better outcome than dying - is seki usually considered life in such problems? Also, is my evaluation right, is this seki?

User avatar
HermanHiddema
Gosei
Posts: 2011
Joined: Tue Apr 20, 2010 10:08 am
Rank: Dutch 4D
GD Posts: 645
Universal go server handle: herminator
Location: Groningen, NL
Has thanked: 202 times
Been thanked: 1086 times

Re: Is this L&D scenario seki?

Post by HermanHiddema »

Black's goal is to live. After :b5: he has achieved that goal, as there is no way for white to capture black any more. The fact that black cannot capture those three white stones is not relevant to solving the problem.

So yes, it is seki, and that seki solves the problem.
xed_over
Oza
Posts: 2264
Joined: Mon Apr 19, 2010 11:51 am
Has thanked: 1179 times
Been thanked: 553 times

Re: Is this L&D scenario seki?

Post by xed_over »

don't think of seki as "Whoever goes first loses" (as you say in your sgf example).

instead, think of seki as dual life -- both live.
skydyr
Oza
Posts: 2495
Joined: Wed Aug 01, 2012 8:06 am
GD Posts: 0
Universal go server handle: skydyr
Online playing schedule: When my wife is out.
Location: DC
Has thanked: 156 times
Been thanked: 436 times

Re: Is this L&D scenario seki?

Post by skydyr »

Also, in your example, :w6: is unnecessary. Black can't capture white's stones even with that liberty, because white can throw in to the center of the three stones and reduce black to one eye.
Boidhre
Oza
Posts: 2356
Joined: Mon Mar 05, 2012 7:15 pm
GD Posts: 0
Universal go server handle: Boidhre
Location: Ireland
Has thanked: 661 times
Been thanked: 442 times

Re: Is this L&D scenario seki?

Post by Boidhre »

Seki is considered life but inferior to unconditional life and usually better than a ko for life if I remember correctly (unless you're given a specific thing to find, e.g. a two stage ko for life or whatever).
User avatar
karaklis
Lives in sente
Posts: 797
Joined: Tue Apr 20, 2010 2:14 pm
GD Posts: 600
Has thanked: 93 times
Been thanked: 105 times

Re: Is this L&D scenario seki?

Post by karaklis »

Boidhre wrote:Seki is considered life but inferior to unconditional life and usually better than a ko for life if I remember correctly (unless you're given a specific thing to find, e.g. a two stage ko for life or whatever).
Yes, unless you need to win the ko to win the game.
Boidhre
Oza
Posts: 2356
Joined: Mon Mar 05, 2012 7:15 pm
GD Posts: 0
Universal go server handle: Boidhre
Location: Ireland
Has thanked: 661 times
Been thanked: 442 times

Re: Is this L&D scenario seki?

Post by Boidhre »

karaklis wrote:
Boidhre wrote:Seki is considered life but inferior to unconditional life and usually better than a ko for life if I remember correctly (unless you're given a specific thing to find, e.g. a two stage ko for life or whatever).
Yes, unless you need to win the ko to win the game.
Sorry, I was unclear. I meant in the context of tsumego, normally a seki solution is wrong if there exists an unconditional life solution and so on.
DrStraw
Oza
Posts: 2180
Joined: Tue Apr 27, 2010 4:09 am
Rank: AGA 5d
GD Posts: 4312
Online playing schedule: Every tenth February 29th from 20:00-20:01 (if time permits)
Location: ʍoquıɐɹ ǝɥʇ ɹǝʌo 'ǝɹǝɥʍǝɯos
Has thanked: 237 times
Been thanked: 662 times
Contact:

Re: Is this L&D scenario seki?

Post by DrStraw »

Boidhre wrote:Seki is considered life but inferior to unconditional life and usually better than a ko for life if I remember correctly (unless you're given a specific thing to find, e.g. a two stage ko for life or whatever).
Seki IS unconditional life.
Still officially AGA 5d but I play so irregularly these days that I am probably only 3d or 4d over the board (but hopefully still 5d in terms of knowledge, theory and the ability to contribute).
Boidhre
Oza
Posts: 2356
Joined: Mon Mar 05, 2012 7:15 pm
GD Posts: 0
Universal go server handle: Boidhre
Location: Ireland
Has thanked: 661 times
Been thanked: 442 times

Re: Is this L&D scenario seki?

Post by Boidhre »

DrStraw wrote:
Boidhre wrote:Seki is considered life but inferior to unconditional life and usually better than a ko for life if I remember correctly (unless you're given a specific thing to find, e.g. a two stage ko for life or whatever).
Seki IS unconditional life.
You are correct, I should have said independent life? (I've always had trouble considering seki as unconditional as I've always thought of unconditional implying an ability to tenuki by the defending player, at least once regardless of who begins the sequence. I see that I'm incorrect though.)
hyperpape
Tengen
Posts: 4382
Joined: Thu May 06, 2010 3:24 pm
Rank: AGA 3k
GD Posts: 65
OGS: Hyperpape 4k
Location: Caldas da Rainha, Portugal
Has thanked: 499 times
Been thanked: 727 times

Re: Is this L&D scenario seki?

Post by hyperpape »

Yeah, there's not a good English term for life without seki, as far as I'm aware. It would be convenient if there were, and would probably help avoid potential confusion with "unconditional life".
Bill Spight
Honinbo
Posts: 10905
Joined: Wed Apr 21, 2010 1:24 pm
Has thanked: 3651 times
Been thanked: 3373 times

Re: Is this L&D scenario seki?

Post by Bill Spight »

hyperpape wrote:Yeah, there's not a good English term for life without seki, as far as I'm aware. It would be convenient if there were, and would probably help avoid potential confusion with "unconditional life".
Well, another term for seki is mutual life. Independent life makes an obvious contrast.

As for unconditional life, it means something different in the context of tsumego (life without winning a ko) and in the context of static determination of life and death (life without placing a stone). Seki is unconditional life in the first sense, but not in the second sense. For the second sense I have suggested invulnerable or immortal, Charles Matthews has suggested safe.
The Adkins Principle:
At some point, doesn't thinking have to go on?
— Winona Adkins

Visualize whirled peas.

Everything with love. Stay safe.
Bill Spight
Honinbo
Posts: 10905
Joined: Wed Apr 21, 2010 1:24 pm
Has thanked: 3651 times
Been thanked: 3373 times

Re: Is this L&D scenario seki?

Post by Bill Spight »

xed_over wrote:don't think of seki as "Whoever goes first loses" (as you say in your sgf example).

instead, think of seki as dual life -- both live.
"Whoever goes first loses" is slightly inaccurate for this seki. "Whoever plays first loses" is accurate, as long as we mean playing a stone in the seki. That is not true for all seki, however, so xed_over is right. :)
The Adkins Principle:
At some point, doesn't thinking have to go on?
— Winona Adkins

Visualize whirled peas.

Everything with love. Stay safe.
gowan
Gosei
Posts: 1628
Joined: Thu Apr 29, 2010 4:40 am
Rank: senior player
GD Posts: 1000
Has thanked: 546 times
Been thanked: 450 times

Re: Is this L&D scenario seki?

Post by gowan »

Depending on the rules used a life-in-seki position might be inferior to a two-eye life because the two-eye life gives territory while points in a seki are not counted (Japanese rules)

It's a bit off topic but I think it is worth mentioning that one way of living may be preferable to another because of subsequent endgame plays.
User avatar
HermanHiddema
Gosei
Posts: 2011
Joined: Tue Apr 20, 2010 10:08 am
Rank: Dutch 4D
GD Posts: 645
Universal go server handle: herminator
Location: Groningen, NL
Has thanked: 202 times
Been thanked: 1086 times

Re: Is this L&D scenario seki?

Post by HermanHiddema »

gowan wrote:Depending on the rules used a life-in-seki position might be inferior to a two-eye life because the two-eye life gives territory while points in a seki are not counted (Japanese rules)

It's a bit off topic but I think it is worth mentioning that one way of living may be preferable to another because of subsequent endgame plays.
Independent of the rules a life in seki position is inferior because it also depends on none of the surrounding groups dying.

In fact, if we take the word "unconditional" literally, seki is not unconditional life because it is only alive on the condition that none of the outside groups die.
skydyr
Oza
Posts: 2495
Joined: Wed Aug 01, 2012 8:06 am
GD Posts: 0
Universal go server handle: skydyr
Online playing schedule: When my wife is out.
Location: DC
Has thanked: 156 times
Been thanked: 436 times

Re: Is this L&D scenario seki?

Post by skydyr »

gowan wrote:Depending on the rules used a life-in-seki position might be inferior to a two-eye life because the two-eye life gives territory while points in a seki are not counted (Japanese rules)

It's a bit off topic but I think it is worth mentioning that one way of living may be preferable to another because of subsequent endgame plays.
Conversely, there are positions where both seki and independent life are possible, but seki gives you more points (independent life requires a sacrifice of some sort).
Post Reply