shape move

[Bill Spight]

Count the stones, including the one White stone captured in the top left.

Hmmm... Maybe F16 needs a white stone?

Yeah, that makes sense of the stones on the board, and it would make a better problem, eh?

[Bill Spight]

As to the problem at hand, my first thought was a probe (B17) with a view to seeing whether F14 might work? Did that underlie you first thought, too?

With the missing White stone at F-16, I expect that B-17 is a standout.

[Bill Spight]

I remember being taken aback when discussing some position with Charles Matthews where I was convinced about the choice of move. I can't remember the details of my own thoughts but they certainly had nothing to do with numbers. Charles agreed with my choice and - the bit that surprised me - added by way of explanation something like, "Well, that would be so - Black and White have an even number of stones." When I asked whey he thought along those lines he said it was just because he was a mathematician (superior don actually!) and numbers came naturally to him. Maybe others here have that mindset?

Well, sure.

I have mentioned this before, but back in the 1990s I spent some time trying to classify professional plays. To my surprise I found that most of them were what Wilcox calls contact plays, adjacent to or diagonally adjacent to other stones. At first I thought of a classification scheme in terms of the number of stones of each player in a given area, but soon realized that a better scheme was the sum and difference of the players' stones. For instance, instead of Black 3 stones vs. White 1 stone it seems better to think of Black being 2 stones ahead with a total of 4 stones. When I did that I found that pros most often played a stone to catch up to the number of opponents' stones, which is what Charles gave as a reason. Next comes playing one more stone in an area than the opponent has. Next comes playing to almost catching up to the opponent and having one less stone. Next comes getting two stones ahead. I think this is a good heuristic for beginners, who know nothing about go but know how to count. It is also the case that generally the more stones there are in an area, the less urgent it is. The main exception has to do with captures and threats to capture.

Centuries ago the best players used to start games by playing 3-4, approach, and pincer. The pincer goes one stone ahead, but playing in an empty corner would do so in that area, as well, and the pincer, despite appearances, is not as good as playing in the empty corner, as a rule. The best players learned that from experience. The heuristic says that the empty corner is better, because it has fewer stones. Similarly, Uberdude learned from bots not to reply to an approach to a 4-4, but to play an approach himself. The heuristic also indicates that. Playing catchup is slightly better than going one stone ahead, and playing where there is one stone is better than playing where there are two stones. (The heuristic would not recommend making an enclosure, even thought there is only one stone there, since that would mean going two stones ahead.)

OC, there are many cases where the heuristic does not work, such as invading an area where the opponent has three or more stones.

[jaca]

we need clarification as to whether there is a stone missing somewhere.

To irgo is human, to forgive Divine

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So i forgive you Doubting Thomases, O ye of little faith. Let he who is without Sin cast the first missing stone into the bowl of Liff, and let us pray to Go (swt):

Dear Go, ooo you are so big! Forgive us our trespasses, as we forgive those that trespass against us

As naught but a mere concubine of Go, i too struggled with the Count, and had to backpedal a couple of times when creating the .sgf, because i too had forgotten to consider the possibility that it was a 2-stone handicap game.

Having sorted that out, i was then forced also to rub out the pesky last move marker which cgoban insists upon adding like some thief-in-the-night Banksie stealing the beauty of a virgin wall and turning it into an eyesore, because that blasted dot attracts the eye more sharply than any liberty or lack thereof. And the last thing i wanted to do was ruin the beauty of the author's problem by attracting the reader to one particular part of the board - although, dare i say it, that esteemed author had herself ruined its beauty by putting "a, b, c, d", etc in various places that i'm not going to tell you about until later.

As to the kafirs' accusation that F16 is not a gloriously empty sky but a tawdry white aeroplane (the only real aeroplane in the entire sky apart from a few fakenews helicopters, none of which went around the back, for obvious reasons), i say unto them:

Chide not the straw in another's eye, for the mote in your own is so much greater

.

But that does at least give me a heavensent opportunity to justify a complaint against the Gods that created this Palace of Untruth Yoseing About All over the Place, for denying us the Right to Fork Off a branch so as to not derail the monorail of fucus on the One and Only True Topic, which is, since you will all by now have completely forgotten what that was:

======= black to play... ======
(and no cheating by asking Laizy to Ease your Use, as i will do that for you in a moment
and - GOLDEN RULE: No talking about each other's moves, not yet,
and - pretty please - will the ones sitting at the front shut up for a minute and give the ones at the back a chance to speak)

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[Bill Spight]

As naught but a mere concubine of Go, i too struggled with the Count, and had to backpedal a couple of times when creating the .sgf, because i too had forgotten to consider the possibility that it was a 2-stone handicap game.

Having sorted that out,

So you are saying that it was a 2 stone game? Under what rules? It matters.

As to the kafirs' accusation that F16 is not a gloriously empty sky but a tawdry white aeroplane

Please be aware that kafir is an insult.

[jaca]

insult

Shush up at the front! We can fork off to sidetracks in another thread,

but since you mention it, kafir is not an insult - its is an Arabic word meaning "unbeliever".

I, for one, am a happy atheist, happy to be called a kafir.

You are mixing up kafir with "kaffir", an Afrikaans word which had originally, in the mouths of God-fearing Dutch and Belgians, who had fled to their Promised Land of The Cape of Good Hope to escape the persecution of the Catholic Church, much as the Pilgrim Fathers fled Cornwall to escape the persecution of the English Church, also meant "unbeliever" - it only took on its racist overtones in later years, when waves of immigrants from further north started to unsettle the settlers.

[Bill Spight]

insult

Shush up at the front! We can fork off to sidetracks in another thread,

but since you mention it, kafir is not an insult - its is an Arabic word meaning "unbeliever".

I, for one, am a happy atheist, happy to be called a kafir.

You are mixing up kafir with "kaffir", an Afrikaans word

Thanks. I was only aware of it as an alternate spelling for kaffir.

[Bill Spight]

So what are the go rules? It does matter.

[jaca]

https://www.lifein19x19.com/viewtopic.p ... 24#p241524

update: here's a cleaner .sgf than the one i first posted, which contained lots of false trails i had laid in trying to get the picture to come out right.

18.sgf

(3.38 KiB) Downloaded 634 times

upupdate: so far, we've had half a dozen dan answers, and only one kyu answer, so as the problem was set by its author for kyus as well as dans, please can some more kyus out there redress the current inbalance by sharing your thoughts?

and, please can we have no more dan answers until some more kyus have had a go at it, whereupon i will tell you the author's answer, and her reasons for it.

To encourage the kyus, i can tell you this much: so far, none of the dans have found the author's answer so you might beat them to it!

To give you a bit of help, here are two ginormous hints:

1. at this - or indeed, any, stage of the game, it is the overall situation that matters most; tactics should serve strategy.
2. the title of the thread is a massive clue - it's got something to do with shape,

and since all anyone talks about these days is what LZ says, it may be timely for beginners to do a tiny tiny bit of homework first on what shape means in Go - you don't have to read the whole book, just Google some of the words.

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[Knotwilg]

My first thought was the peep at L15 but if white pushes up the cut doesnt look that good. Still, it plays away from thickness and harasses the weakest group

(removed side note)

[jlt]

(Comments to Knotwilg's side note deleted, since they are off-topic. I hope other fellow kyu players will jump in and share their thoughts on the position.)

[jaca]

would anyone wishing to raise a side issue please be so kind as to do so in shape move fork, created especially for that purpose, so as to keep the focus of this thread purely and simply on black to play.

NO MORE DAN answers PLEASE, we already have enough of them to build the big picture - please let the kyus have their say now

[marvin]

Hi L19 , long time no see.
My kyu answer: N16, close to the W weakest group, maybe cut afterwards and get some points...

[Aidoneus]

I like Uberdude's idea. But you insist on something else, and some kind of shape move at that... How about L8? If the insistence was not on "shape" I probably would have said P12 or P11. Also, I almost answered G6 cause of the shape caveat, but then I am just a patzer and that moves seems too slow to me.

[jaca]

when answering, please declare your rank, or at least whether you are kyu or dan, to help me assemble the big picture afterwards. i am going to assume that Bacchus was drunk when he said, as many drunks do, "i jus' lov yer, mate!"

and please please do not comment on others' answers, as that renders your own contribution ineligible for consideration as an independent opinion.

of course, once an opinion has been expressed, it inevitably at least indirectly colours everyone else's answer, but the damage has already been done, so we'll just have to make of it the best we can.

had i thought about my experiment more carefully, i would have insisted that higher ranks wait until lower ranks had a go at it, but it's too late now. never mind, at least the highest rank (the author) has been silent so far, so there is still something we can all learn from her.

once i have the raw data, and have done with it what i can, the door will be wide open for you to pat each other on the back, or stab each other in the eye, whichever takes your fancy.