I am continuing to proof read through my new edition of commentaries on Shuei's games (about 50% bigger), but a big difference this time round is that I can look at many comments through the prism of AI.

One thing I noticed before, and remarked on several times in the first edition, is that Honinbo Shusai had a great predilection for 'check' moves (tsume), which he recommended in various places and for various reasons. There are grounds for believing he got this fondness for checks from Shuei, though perhaps he took it further.

But one aspect of the continued preference for tsume is that, in very many cases, he uses tsume for a move I, along with western players in general, and possibly along with modern Japanese writers, would call a pincer. An example (a 2-stone game) is below, though this is from Karigane Junichi rather than Shusai.



White has just played at the triangled point and in the game Black responded at A. Karigane said this should have been the tsume at B (since he was Black playing his teacher Shuei in this game, I think we can assume the comment really came from Shuei).

I believe most of us here would call B a pincer. There may be some interference from the fact that, until tsunami became a popular word in English, the ts- sound of tsume was something English speakers tried to avoid, and 'check' of course has interference from chess. But I have noticed that 'pincer' is a far commoner word among English-speaking players than hasami is among Japanese pro commentators.

Previously that observation was just tucked away at the back of my mind, but I have brought it back to the forefront of my mind because of the observation repeatedly made here that AI bots seem to shy away from pincers.

I have therefore been checking up on some examples in the Shuei commentaries, and it seems that in fact bots like pincer moves that are not really pincers but are tsume moves (as defined by the likes of Shusai). The applies to the example above. Lizzie 0.7 gave me B as first choice, although only a smidgeon better than a range of other possible moves (which did not include A but did include a couple of third-line moves in that area).

Assuming this is all an accurate observation (I do have many examples) I can't say much about what it all means. What I can add is that the special case of a pincer-cum-extension often seems favoured by bots, and a so-called pincer that is really a tsume is favoured. In the case of a pincer that does not have either of those extra attributes, bots seem to prefer a move inside the corner (or tenuki).

I think it is useful to add that the commentaries I am referring to were nearly all by players of the past in the days when they wrote their own commentaries and so used their own terms. They differ, both in choice and range, from modern terms. For example, tsume is much more common among them than nowadays, but they also distinguish e.g. between tsume and tsumeyori (I discuss that in my Go Wisdom appendix). From about 1930, amateur go journalists largely took over and changed much of the existing terminology, and added new terms. And also - my speculation - framed it more as if seen through amateur eyes than pro eyes? If so, that distortion is what we have inherited in the West.

What do you think about the validity of a pincer/tsume dichotomy?

For quite some time now I have been calling plays like B a pincer cum extension or vice versa.

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

Visualize whirled peas.

Everything with love. Stay safe.

Not every move that looks like a claw is a claw.
Without support it is just a little paw.

I think of pincer/tsume as synonyms and not as a dichotomy. Pros would just not play a bad claw and therefore not call it a claw at all. But who am I. Your precision and attention to detail in interpreting the japanese go comments is much appreciated. I am always keen on your views and thoughts on the matter and ready to change my mind.

Could it have anything to do with how strong the "pincering" stones are on both sides of the pincered stone? In the example it seems that White has a lot of options other than running out. I think of "tsume" as blocking some direction, not just attacking. In English the pincer attack emphasizes the attack doesn't it?

B is a pincer in relation to the white f3 stone (because there's a black stone on the other side of it at d4), and an extension in relation to the black n3 through m5 group. So I don't see a dichotomy, but a synergy, of a move doing 2 useful things at once.

I found this https://senseis.xmp.net/?TsumeDiscussion from 2003 but the plot thickens because it is a discussion of a 1969 BGJ article by Takagawa which explains this mysterious tsume move http://www.britgo.org/bgj/00810.html

Anyway, if I understand Takagawa then tsume is a check as in a move that stops the opponent from making an extension but moves that are going for something else are excluded by Takagawa. He seems to exclude moves that build territory, expand corners or challenge safe groups (or I guess diagram 9 is just showing a white approach move). He just gives some examples of moves that are not checks, saying that an "expert" would understand that these moves have a different meaning.

In reality it seem unlikely to me that this term is used as precisely as the article indicates, not because I know any Japanese but because even "experts" tend to be lazy with terminology at least sometimes.

I don't think it's a matter of laziness, but just the natural fuzziness of language. I doubt if pros ever argued in a game review whether a play was a tsume or not.

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

Visualize whirled peas.

Everything with love. Stay safe.

I meant "lazy" as a principle of least effort not as something negative.

I only base my assumption that this is difficult on this article. It appears to be suggested that it is above some peoples heads

I think the main point is being missed, and that's because people (and that includes me) are extraordinarily reluctant to question their use of language. I've come across this before in go with people refusing to question their uses of terms like 'invasion', 'yose' and 'thickness'. It happens everywhere outside of go, too. It's as if language becomes a belief system and challenging it provokes a bristly response. FWIW, in my experience with English, non-native users of English are more porcupiney than natives, and I suspect that may be because they have had to put much more obvious effort into learning the language, whereas the natives sup it up like mother's milk. But natives are rarely less than hedgehoggy. We may be seeing similar curl-in-ball entrenchments here with arguments over the meaning of probability and win rates.

So let me try to put it all a different way.

I have observed many cases where a move could plausibly be called a pincer yet a Japanese pro from the past has called it a tsume. As I have said, I would have used the word 'pincer' - that's why I noticed the phenomenon after all. But the choice of which term to use is not random. It's happening too much for that, and with no good counter-examples.

So you might just shrug and say it's six of one and half dozen of another. But I dispute that. A bottle can be half-full or half-empty. Experience tells us that the choice here is not random either. People who routinely choose 'half-full' we regard as optimists. Half-empties are pessimists. The choice has meaning.

My question about pincer and tsume wasn't about what term you, as a western amateur, use. It was, making the assumption that the different choice that we and old pros appear to have made was likewise not random and therefore had meaning, what is the meaning behind the choice? For example, we might say that a player who calls it a pincer is attacking, trying to keep the initiative, or whatever. Or he may have just read too many joseki books. Pincer is a very common word in such books. Tsume is very rare. Does that tell us that pincer is more tactical and tsume more strategic? For example, the meaning of a tsume may be prophylaxis, patience, setting up miai. Or what? That is what I'm asking. I'm suggesting the old pros saw something 'theoretical' we amateurs miss, and the clue to the difference may be in the words.

Let me go off on a bit of a tangent now so that I can reinforce that core issue.

We, modern pros included, have all been surprised by many of the moves played by AI bots. One example is the early or frequent shoulder hit. Whenever we adopt a term, we take on board a lot of associations. These associations can differ markedly from person to person, but there tends to be a common core. In the case of shoulder hits, I think the common core includes the idea that a shoulder hit is an erasing move. That is why we evince so much surprise when we see a shoulder hit on move 4. How can that be erasing anything?

We have the same bafflement about early contact plays. We've been taught to use these only for making sabaki and so on, and to avoid them elsewhere as they strengthen the opponent and produce ajikeshi. But bots happily commit these 'sins' and instead of saying the bottle is half empty, take the positive half-full view that the effect is to overconcentrate the opponent.

I would speculate that, over time, terms will evolve to distinguish these different uses of shoulder hits and contact plays, and I am further wondering whether something like that has happened with pincer and tsume, but we just haven't noticed it yet, and the reason we haven't noticed is because commentaries by old pros in English are still rather rare. I notice it because I am working on masses of such old commentaries, but I don't yet understand the putative difference. So, again, that is what I am asking about.

Can you have a tangent to a tangent? Well, I don't care if you can't, I'm going off on one anyway. I want to explore the notion that terms matter.

Imagine a language where there was word for half-full and all bottles that were, er, half-full would have to be described as half-empty. That would mean we'd lack an easy way to spot optimists. Does that matter? Well, the same thing happens in real life and people buck against it. For so many things we have either a single term or a preponderant term, and that means we lack ways to spot another point of view. For example, masses of people are just lumped together as black, disabled, female, or whatever, and the core associations linked with that preponderant word dominate any discussions about the people themselves, usually in a deprecatory way. That is why some people try to change the terms, or introduce new ones (e.g. not black but person of colour, not disabled but physically challenged, and so on). They hope to shift the whole tone of debate over their particular issue. Whether you agree with it as 'woke' or just label it as political correctness, at least the level of awareness (i.e. knowledge) is increased.

So, for the third time (or is it the fourth? Who cares? They're only numbers!) I am asking whether there is something to be learned from noting a possible semantic dichotomy between pincer and tsume in those situations where one or other could be used? Whichever side of the question you choose to come down on, or whether you think it's all a non-issue anyway, you might find that it will act like an ear-worm, and in future games you will be thinking about pincers and tsume more than ever before. And in this process of 'effortful practice' your level of awareness will increase! Your knowledge may thereby increase, too.

How would have a Chinese pro called this move ? And a Korean one ? Do the words they use have the exact same meaning ?

So what is the exact definition of a checking extension?

For instance, the link https://senseis.xmp.net/?TsumeDiscussion says:

Why isn't it a checking extension? Because is overextended, so an invasion at "a" is possible? Contrary to the example 4 below?

Click Here To Show Diagram Code

[go]$$B Checking extension
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . X O O . . . . O . 1 . . X . . . . . |
$$ | . . X , O . . . . , . . . . . , X . . |
$$ | . X . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |[/go]

Good question!

Well, I'm the happy owner of the newly published Chinese-English Dictionary of WeiQi Terms.

I found two entries that relate to this discussion.





拆兼夹 is similar to the example given by the OP. There is one difference in that the move in the OP example could be seen as more of a defense.

逼 kind of coincides with the sensei library entry (there is 拆逼 and 拦 on senseis but I won't say more because my Chinese is crap), block is a synonym of check in English when used as a verb.

These are obviously simplified characters but anyone who is interested can look up Japanese or traditional versions on Wiktionary.

Yes, it is sometimes useful to reflect if a glass is half full or half empty.

And there is already a lot of thinking going on related to pincers/claws/tsume moves because of the original post. So the dichotomy proves to be quite helpful.

I for one am intrigued and if it's just from a student point of view. When there is a difference between pincer and tsume then I imagine there must be different concepts behind it and understanding them could lead to a greater understanding of go. I'd like that.

Right now, in my limited understanding, I recall my early misconceptions of josekis leading to an "equal" result. They do - on an empty board (although quite a lot of them are undergoing change right now...). In practical play (certain) joseki moves are often at least strategically invalid and in some situations even no joseki move was called for. AI now tenukis mid-joseki leaving behind an aweful local result but still profits globally from getting two moves elsewhere.

So for me the concept of joseki is increasingly meaningless now. What's left is a hole filled with questions: When to tenuki? How to judge/evaluate positions after tenuki? What's the goal globally by accepting "a loss" locally?

But then again, when there are no fixed sequences anymore, maybe there are no fixed concepts as well : D

_________________
My "guide" to become stronger in Go

Actually I tend to lean the other way: I question language so much that it's hard to get attached to specific names! On the one hand I do agree with Ursula LeGuin that names can have power in the right context; but the power isn't absolute, and an awful lot happens inside our heads that's not attached to language. The Sapir-Whorf hypothesis has been pretty controversial, and I've never found it awfully convincing.

That said, there's great value in a conversation that motivates us to look at lots of go positions and think carefully about the difference between them! Thanks John for raising such a fascinating question.

We don't seem to be making any progress on getting to the meaning behind the relevant words. I didn't want to steer the talk so didn't give my own impressions, but I'll do that now.

I think fundamentally the difference between the mindsets of playing a pincer and a check is to do with the difference between sente and the initiative.

When you look at (Japanese) commentaries on old games you see much discussion of which is the right pincer to play, and we can discern that the old players themselves were asking the same question. They experiment with each pincer and if they think they've found a key point, that pincer can become the fashion for a whole generation. But then they end up confused again.

I think the confusion is inherent in the position. A pincer is essentially a tactical move. It is a sente move. It expects a response (the gote move) and then sente follows that gote, another sente/gote follows that, and so on remorselessly. What we fairly typically end up with is a running fight into the centre. Put it another way, we end up with unpredictability. Worse, for the sente player it's very often a predictable unpredictability in that it ends up with having chased his opponent's group into a strong position (eyes or connection) while his chasing stones end up swimming in a sea of weaknesses. He has become the victim of amarigatachi. His opponent has duped him with amashi. Amashi was commoner and/or more obvious in Edo times than in modern times because the rank differences were greater then. Even weakfish players could see the poor results of their play, but didn't have much idea how to improve it. So, try another pincer! What they should have been doing was: try another strategy - maybe a tsume.

Let me go back over some of that paragraph. Nearly everyone reads forum pages far too quickly (the boss might walk in!), and misses the real points. I want to slow things down. My "another strategy."

Sente means making the first stroke as in a sword fight. Gote means making the responding stroke. They go hand in hand, walk in step, cancel each other out, etc. etc. There is thus no inherent real advantage in having sente. We saw that with Muhammad Ali's rope-a-dope against Sonny Liston. Liston took sente, Ali had gote. Liston tried pincering Ali between his massive paws. Ali parried and ran away. Liston ended up a spent force. Ali ended up with the initiative and victory.

A sword fight is mostly about sente and gote. Victory likewise depends on something else: the initiative. Imagine a totally different kind of sword fight. You have a prisoner strapped to a chair. Above him, by a thread, hangs the Sword of Damocles. If he doesn't cooperate, that thread might be snapped. Boy, do you have the initiative - sente is irrelevant.

How might that translate into go? One common way is that you have a sente-gote skirmish, marching step in step, until you decide it is safe to break off and play a move elsewhere where there is a sente but no gote. You have stolen a march. Instead of thinking about keeping on attacking in the skirmish you grab the tedomari (the last available move, where there is a sente but no gote) in another position. This is often described in commentaries by way of phrases such as being the first to get to some move (e.g. a shimari in the last still-open corner). You are now ahead in the balance of territories. You have the initiative. You have real control. You are no longer playing protagonist and deuteragonist in a Greek tragedy. You are now a god on Mt Olympus.

If you are a real god, like an AI bot or Go Seigen, and have Ali's speed of foot, you can even dispense with the skirmish to settle a local position and just tenuki straight into the tedomari.

I believe that many old players understood all that at the results end of the process. They mostly just couldn't see how to get there. Great players like Shuei did see ways, such as proper use of miai. But those insights are what made them great. They were individual, not mainstream.

Eventually, though, the tributary did flow into the main river, and I think there were two main impulses. One was the use of tsume. It might be the same move as a pincer as regards being a point of the board, but the best old players (led by Honinbo Shusai) eschewed the pincer mindset and shifted allegiance to the tsume party. They shifted from sente to initiative.

So why is a tsume initiative-rich rather than sente-rich? I would say the difference lies in the fact that a pincer attacks the opponent whereas a tsume pressurises the opponent. On the surface the difference is actually wafer-thin, and the term 逼 both illustrates and implies that. Japanese pros (amateurs only rarely) use that character in the term 'semaru' = press/approach right up, which - as you can easily see - is related to 'semeru' = attack.

But the difference in mindset can be enormous. With tsume, your subconscious mind is now thnking about safety, prudence, honte, keeping options open (miai), control, the initiative. The pincer player's subconscious is instead looking forward to the roller coaster ride and all the fun of the fair - and it lets your stomach worry about the effects of feeling queasy after guzzling too much candy floss and hot dogs.

A more mundane analogy? You have £100 to spend and walk into an antiques shop. You are the pincer type. You don't want to waste time asking the price of each item one by one, so you say to the dealer: I've got £100 to spend - what can you recommend. He shows you a £5 vase, only it just happens to be on sale now at £100. You buy it. You have been duped. You have been rope-doped. You have suffered amarigatachi. Serves you right. But you learn your lesson and next day you become a tsume player. You do some preparation. You put on a tatty jacket, practise your shrugs in a mirror, and only then go to the shop. You don't tell the dealer anything. You just pick out a piece you like - maybe a £5 vase. You ask what it might cost. Dealer looks at you, decides you could barely afford a coffee, but that vase has been hanging around for quite a while, so he decides to shift it - £5 to you, sir" You delve into your shrug repertoire. The dealer either relents and knocks another couple of quid off the price, or he sticks to his guns. But even then you have lost nothing. You pay £5, not £100.

While I think this process is going on all the time in high-level go, it is not easy to see and even harder to copy - even for other pros. That is why I think another approach to keeping control of the game (i.e. the initiative) was tried.

Everyone who's looked at more than a few Edo games will have noticed an absence of high pincers. What I think was behind the actually rather slow development of high pincer play (I am not counting taisha as a true pincer BTW) was not an attempt to try yet another pincer of the sente-gote tactical type. Rather it was to do with kurai - a position relatively higher than your opponent's. Typically a fourth-line play as opposed to a third-line play. I think Edo players avoided this because the centre was just too hard to control. Too speculative. But modern players had the benefit of the experimentation in the centre of Shin Fuseki and became more comfortable with early centre-facing plays. They also had the benefit of Shuei's games in which he demonstrated control of the game via control of the centre, especially using his favourite L shapes (magaris). Shuei was not quite in the modern category because even he found control of the centre early on a tad too difficult, although with his frequent use of star point corner moves he was moving that way. I think we can safely say that the player who brought the kurai mindset to full fruition was Takagawa Kaku. He referred to it as 'balance'. (And guess who his favourite player was.)

But go is so rich that we could have players like Takagawa's great rival, Sakata Eio, who didn't have much truck with kurai and instead and so often sharpened his razor to cut at the jugular of opposing groups on the second line. Sakata was like the bantam cock in the Corries' famous song:

He was a fine upstanding bantam-cock
So brisk, and stiff, and spry...
With a springy step, and a jaunty plume
And a purposeful look in his eye
In his little black laughing eye!

So I took him to the coop and introduced him to
My seventeen wide-eyed hens
And he tupped and he tupped as a hero tupps
And he bowed to them all, and then
He up and took 'em all again!

Well then upon the peace of my ducks and geese
He boldly did intrude
And with glazed eyes and opened mouths
They bore him with fortitude...
And a little bit of gratitude!

He jumped my giggling guinea-fowl!
He thrust his attentions upon
Me twenty hysterical turkeys,
And a visiting migrant swan!
And the bantam thundered on!

He groped my fan-tail pigeon doves
And my lily-white Columbine
And as I was a lookin' at me budgerigar
He jumped my parrot from behind!
He was sittin' on me shoulder at the time!

But all of a sudden, with a gasp and a gulp
He clapped his wings to his head!
He lay flat on his back with his feet in the air;
My bantam-cock was dead!

And the vultures circled overhead!

What a noble beast!
What a champion cock!
What a way to live and die!
But as I dug him a grave to protect his bones
From those hungry buzzards in the sky
The bantam opened up a sly little eye!

He gave me a wink, and a terrible grin
The way that rapists do....
He said, "Do you see them silly daft buggers up there?
They'll be down in a minnit 'er two!
They'll be down in a minnit 'er two!"

I suspect that bantam Sakata had more influence on go after him than did buzzard Takagawa, and high pincers, therefore, while still common enough in modern play, can't really be said to rule the roost. Although... evolution is like an underground moving river - one of Takagawa's favourite images - and maybe AI is shifting the balance back towards the daft buggers

But to get back to Maître Pathelin's yowes rather than the birds: pincers and tsumes. My conclusion is that they are both useful tools but belong in different toolboxes. They form part of separate nexus. For me, the associations of pincers include sente/gote, tactics, attack, lack of bases, danger of being bitten in the bum, confusion, fashion, joseki books, amateurs. Tsume associations for me are safety, bases, prudence, patience, creating options, strategy, blocking, true control, initiative, pros but not just any pros - top ones and Shusai especially. YMMV.

There! That's filled in a coffee break and a half for you better than work ever does!

If you've still got any energy after that diatribe, or leisure to spare, you might like to listen to the Bantam Cock brilliantly sung. Try https://www.youtube.com/watch?v=B5wXb9XJicM

Click Here To Show Diagram Code

[go]$$Bcm15
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . O . . . . . . X . X X . . . |
$$ | . . O , . . . . . , . . . O O , . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . 2 , . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . 1 . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . 4 . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . X , X . . . . , . . . . . , . . . |
$$ | . . . . . . . . . X . . . 3 . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

= hiraki
= tsume
= hirakizume

???

Click Here To Show Diagram Code

[go]$$Wcm16
$$ ---------------------------------------
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . 6 4 X . X X . . . |
$$ | . . O , O . . . . , . 5 3 O O , . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . 2 . X . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . X . . . . . , . . . . . , . . . |
$$ | . . . . . . . . . . . . . . . . 1 . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . O . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . X , X . . . . , . . . . . , . . . |
$$ | . . . . . . . . . X . . . . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ ---------------------------------------[/go]

= hirakizume ?

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

Visualize whirled peas.

Everything with love. Stay safe.

Bill

I don't expect everyone always to use the same term because it's like trying blindfolded to pin a tail on the donkey.

But I think intent answers a lot. In your first example I'd agree it's a hiraki because the main intent is to stress expanding so as to make a base. (However, in practice I think it's more likely to be called specifically a nikenbiraki as that is so often seen as a building block for bases, and so it stands out from run-of-the mill extensions.)

Your tsume I agree with (though might expect it to be called tsumeyori to distinguish from the tsume where you hold back one point). I think a big part of the intent behind this move is prudence. It inhibits invasion of the group to the left, prophylactically blocking White from himself making a tsume in the area which would demand a response. It may superficially be an extension but what is it expanding? Nothing.

Judgement on the hirakizume in the first example I would hold in abeyance. If further play shows White was trying to expand his moyo, I'd say hirakizume is fine. If White is just trying to inhibit invasion of the left upper side, just tsume seems more appropriate.

In your second example, I see White 16 as defending the corner with no real idea of expanding so it is tsume to me. It's not really a pincer because it lacks vigour in that regard, but I wouldn't quibble much if someone wanted to stress Black's predicament that way. I would quibble more , but not totally, about calling it hirakizume. Following both Japanese grammar and famous go editor Hayashi Yutaka, I'd say the meaning of hirakizume is hiraki + tsume (precisely that, says Hayashi, and precisely that much is all he has to say about it!). The two elements are equal. This position looks more like hiraku tsume: a tsume which has some attributes of a hiraki about it. Again, though, I'd want to see how White's future plans unfold before committing myself fully.

Many thanks, John.

I was hoping that at some point you might reference Hayashi.

BTW, these examples come from variations of a Genjo-Chitoku game, 1800-02-12a. According to Elf, they made it through the first 50 moves with only a few minor errors. Over the past several weeks I have gone over scores of openings in the GoGoD database commentaries by Elf, and have not seen other players do so well before the AI era.

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

Visualize whirled peas.

Everything with love. Stay safe.

IIUC, by saying that a pincer is sente you do not mean that the player who pincers starts a sequence of play ending with the opponent's move, but that the opponent replies locally to the pincer, regardless of who ends the sequence. Another way of putting that is to say that the pincer raises the local temperature.

I beg to differ about the opponent replying to the pincer. OC, we know that he does not have to. But beyond that, I have long thought that ignoring the early pincer marked the beginning of modern understanding of the opening. I was, OC, aware of such play in the games of Dosaku in the 17th century. This morning I looked at games around 1600 in the GoGoD database, and indeed, in the games that I looked at the players, notably Sansa and Rigen, replied to the early pincers. But by around 1650 players were not replying to the early pincers. And, OC, even later the opening pattern, Black 3-4, White 5-3 approach, Black pincer, White tenuki, was common.

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

Visualize whirled peas.

Everything with love. Stay safe.