I know there are such things as invasions and reductions (duh), but after reviewing several games I wonder if these are a blind spot in my mental framework? I haven't played nearly as many games as my opponents and make all types of big mistakes, but for other aspects of the game I tend to have some opinion and recognize the ideas during review. But with this I don't see it.

There's so many books and problems to study, but what should I read or practice to help specifically with my total obliviousness to the left side in the review below?
Is this a good time to read Attack & Defense?

https://online-go.com/review/670388

It's always a good time to read Attack and Defense. I'm sure you will learn lots of things from it.

Just glancing at your game, it looks to me like E7 is basically playing on dame and forcing White to complete their left side, at a time where there is a lot of open space (between C7 and C12) and White's lower-left stones can come under pressure if they become cut off.

Alright then, I see it recommended everywhere so I guess it's about time.
Chapter 7 in it is called "Reducing and Invading Large Frameworks" so that sounds good.

I'm also considering the book Reducing Territorial Frameworks.
Not looking to study patterns in detail for now, just an overview of the ideas.

Reduction, invasion, attack, defense, fighting and combinations thereof are rich topics, which any selection of few books does not do justice. A book recommended everywhere need not be the most informative book but is mentioned a lot also because it is ca. half a century old. Books mentioned so far do not give an overview of the ideas needed for the aforementioned topics but only give a SELECTION of such ideas. Better keep your mind open to various sources and plan to read everything you can find about those topics. Thereby, you can learn dozens of times as much as from the mentioned books alone.

https://senseis.xmp.net/?GoBooks#toc26
http://home.snafu.de/jasiek/isbn.html#TMiddleGame
http://home.snafu.de/jasiek/isbn.html#TFight

Invasions and reductions are a difficult topic since they're so complex. To get better at them you'll need to:

a) Get better at assessing the whole board.
Counting, in particular, is very important since it'll help you determine whether you need to invade, reduce or continue increasing your own territory. E.g. if you're ahead, reducing is often better while if you're behind on points you should generally invade.

b) Knowledge of key invasion and reduction points.
I've recently bought Reducing Territorial Frameworks but haven't had the time to read it yet so I can't say anything for sure but it does look useful. I've found analyzing my games with AI and watching reviews of professional games to be very useful as well. I'd also suggest playing some games on Pandanet since most players there have a moyo/framework style, so there's lots of opportunities to practice invading and reducing.

c) Sabaki
The right timing and invasion point don't matter much if your group meets a miserable end. Here I'd again recommend AI reviews and studying professional games. In terms of books, Tesuji by James Davies is another must-read. If you've already read it then any other books on tesuji or sabaki should provide some benefit.

Get Strong at Invading (https://www.amazon.com/Get-Strong-Invad ... 4871870553) was the very fist Go book I bought. As a 29 kyu, I had no idea what to buy and the title sounded cool. It was of course over my head, but I memorized patterns initially, then slowly started to understand them over time. Even though the book is at least 25 years old and AI may not like certain moves found in it, I still recommend as a general book of knowledge.

Yilun Yang also has principles books that provide nice heuristics on when to invade, when to reduce, when to run out, when to live. These may be helpful too.

In terms of your OGS game, My first comment would not be on how you dealt with white's low framework on the left side. Instead, my first comment is to say I feel you don't follow through on earlier moves. Example: move 43. If I played this move, it would be as a threat to white's N18 group. But white instead played passively, you responded passively, and forgot about move 43. Another one is move 57. If you play this, you are telling white "I'm going to attack you here if you don't fix yourself" but you then get distracted elsewhere.

I'm also struggling with invasions and reductions. What I'm trying to learn and apply (if correct) is:

An invasion is not merely taking away potential territory, it is also trying to unsettle one of the groups that surrounds the potential territory.
And if the surrounding structures are very strong, then it may be better to reduce.
Unless the moyo is so huge that there's really no other option.

Thank you! I'm looking for a suitable introduction rather than a rigorous treatment at this point, it doesn't mean I won't expand on that later down the road.
That makes sense about Attack & Defense, I wouldn't expect it to be the answer to this question but more something I intend read anyway if only because it's a meme in the go world.

No doubt, and I'm still at the level where my mind takes breaks during the later middle game and yose because it's too much data...

Yes this is what I'm looking for, just enough to have some basic ideas to pin observations from the next 250 games on.

Noted, thanks!

Great, it's even better to get feedback on things I'm not aware of!
I see your point. I wonder if this would be about a lack of game experience, or a character flaw, or if there is a term and/or antidote for it in go?

losipai

You seem refreshingly willing to think for yourself while being willing to learn from other sources. Could I therefore ask a favour before you start reading any books? (And I'm not going to ask you to read any of mine!)

You say you know of invasions and reductions, and so those words are already in your brain. Like every other word there, they must have various associations and nuances which will, of course, be peculiar to you. Would you be willing to share them with us?

If I use myself as an example, when I hear the word 'invasion' the first thing that tends to come into my mind is D-Day. Lower in the scale might be 1066. Exploring the associations further, I see in my mind's eye the result of an invasion being a takeover, of a country or metaphorically of an area of life. I don't really have an antonym for invasion in my brain, nor any close synonyms (e.g. I would never say D-Day Incursion). Any other associations are to do with go.

For reduction, I think normally only of things like reduced prices and weight loss, and it does have antonyms for me, such as 'increase,' and several alternatives. The go usage in my brain is entirely separate from that. It even feels a bit alien to me, perhaps because the first word I learnt for it was 'erasing.'

It would interest me greatly, in fact, if other people would do the same thing. I know from long experience what British speakers are likely to say, but here we have a truly multinational audience and so I would expect quite a few surprises.

If we can get enough responses to make the work worthwhile, I'm willing to offer some deeper thoughts from a linguist's point of view.

Invasions and reductions are not an easy topic. The AI are indicating, it seems to me, a possible third category, which for the moment I am calling shallow reductions. It is not like they are absent from pre-AI pro play, but today's top bots seem to like them quite a lot.



I am having difficulty with this file, both with Safari and Firefox. If it is a review, I don't see any comments or variations. If there is an sgf file embedded in it, I don't see it.

Are you Black?

and look quite skillful to me.
What about B-07?

Are you White?

Learn to sacrifice stones.

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

Visualize whirled peas.

Everything with love. Stay safe.

Maybe lack of game experience. There's the old proverb "Play the urgent point before the big point." It is in my opinion too often neglected. There's a lot of latent power sitting around waiting to be launched - you just need to find it. (easier said than done - ha!)

Uh-oh this linguist is up to no good

I'm not familiar with the forum culture but if it might be useful for the person asking it seems totally fair to mention one's own books!


Very well then, allow me to demonstrate my lack of insight
Invasion seems more general to me than uchikomi which I interpret as a more go-specific play into. Although utsu is also broad. The word invasion I understand as forcefully breaking into something one doesn't own with the intention of keeping it; capture and subsequent entrenchment of something that one considers valuable. I think one could either clearly have the ability to do so, or be in a situation where it's necessary to risk the invasion regardless.

Reduction sounds a bit different from keshi, I can't tell if there's any difference in attitude between the languages with regards to go, but I personally like keshi because it's short and feels more direct.
In go, I might initially assume that we're talking about erasing territory, but I don't know that. It could also be reduction of influence, or simply of "potential" (more abstract).
Additionally it's unclear whether the target of this already belongs to the opponent, or is neutral. It would make sense if there's a spectrum between the two, e.g. it's mostly neutral potential that we want to erase because the opponent is somewhat more likely to benefit from it.
To the extent that it's neutral one would want to eliminate it from the board to deny the opponent, and if it's considered to already belong to the opponent then it is after the fact that it can be erased.
The distinction between these might be irrelevant, because the tangibility of future potential should depend on the player's strength.

As a beginner, and I'm sure I'm oversimplifying, I would say that invading is about whether there is enough space and exploits to live inside an enclosed space, and reduction about limiting the value of something. But unless reduction is part of yose which I believe it generally isn't, reducing limits the value of something that is less clearly defined than territory. For instance a 2nd line kosumi is not considered a reduction. It is not clearly defined but one needs to form an opinion about its worth in order to reduce it. Apart from denying the opponent I guess a reduction might have constructive purposes as well in practice, but those would have to be secondary or we would use another term.

Finally it seems to me as if keshi could imply a relatively low risk of severe side effects if things go according to plan. Otherwise you'd not be erasing but, I don't know, trading, exchanging or fighting.

Whew that's a lot of semantics, is this what you were looking for?

Interesting.

That's weird, I was hoping OGS links were a good way to share games. I use Firefox too. There are no variations but there should be comments right under the uh... move map? for instance for move 97. If you hover the sidebar at the right edge of the window there are options for downloading as SGF or adding variations.

I am black!

I think I can manage that, at least if I don't need to profit from it...

Thanks. Things don't work the same way on my browser, but I have managed to find the comments and options.



That was in case you were White. In this game White was quite stubborn about saving his stones. But it is still good advice for invading. If you invade and try to save all your invading stones, that often invites disaster.

I like to study pro games. Doing so wih the help of today's AI can be quite instructive, but even without doing so their games can be inspirational.

Kitani Minoru made an art form of invading. He performed miracles in that department.

Sakata Eio was quite a fighter. He often got behind in the opening, but triumphed in the middle game.

Fujisawa Hideyuki (AKA Shuko) was a brilliant and flexible player who retained his strength into his later years. He is always worth reading and studying. He was known as a master of the opening. In this game you fell behind through making small plays. His books and games can help develop judgement.

Cho Chikun is an overall master who has also retained his strength.

Lee Changho dominated the go world for quite a while, but people eventually learned how to play against him. He is one of those players who showed great fighting skill in his early days, but whose judgement improved enough so that he did not have to rely upon fighting to take the lead.

Rui Naiwei is also quite a fighter. She milks positions for all they are worth. Good for inspiring follow through.

And, OC, there are more modern pros whom I expect you are more familiar with.

For inspiration about invading, I would definitely start with Kitani. He made magic.

For overall mastery, Cho Chikun is hard to beat.

For study, Fujisawa's Tesuji Dictionary and Reducing Territorial Frameworks are well worth getting.

Good luck!

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

Visualize whirled peas.

Everything with love. Stay safe.

Here is a game by Kitani well after his prime, where he beat one of the young stars of the day. It shows instructive fighting and invasion technique.

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

Visualize whirled peas.

Everything with love. Stay safe.

To John: although I am not a visual person, I have "visuals" for invasion/reduction rather than synonyms or any kind of taxonomy.

What I see is:

| \ O / |
| x-terr |

| / X \ |
| O-life|

A convex end result of a reduction, a concave one for an invasion.

As mentioned before, what I think is wrong about that is that I don't usually take into account the effect of an invasion on the surrounding structure.

So, whether verbally or visually, I think we need words or images that stimulate invasions in case of corrosive structure and encourage reductions in the solid case.

Just out of curiosity, what do you consider Kitani's prime? He was ranked number 5 in mamumamu's historical list for July 1964, which is where this game enters his data. He was behind only Sakata, Go, Fujisawa Hosai, and Takagawa. Hashimoto was ranked 12th in that list.

_________________
Dave Sigaty
"Short-lived are both the praiser and the praised, and rememberer and the remembered..."
- Marcus Aurelius; Meditations, VIII 21

I suppose that Kitani's prime came by 1954, when he fell ill.

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

Visualize whirled peas.

Everything with love. Stay safe.

In terms of title wins and appearances in title matches, Kitani's prime was clearly 1956-1961. He reached 9-dan in 1956.

In terms of when a significant number of people in Japan thought he might be No. 1. it would be around 1938, which perhaps matches his age prime best: he was born in 1909.

As regards illness, the first significant affect on his career was 1954 when he stopped playing in the Oteai, though it had appeared well before then. It ended his career (and school) only in 1974. He died in 1975.

FWIW, my definitions of invasion and reduction are:

An invasion is a stone which is placed in an area which is almost surrounded by enemy stones, which aims
(1) either at living locally (i.e. living while being surrounded)
(2) or at escaping while splitting the opponent into two groups.

The invader may sometimes change his mind, invading stones may be sacrificed in order to get a strong outside influence.

A reduction is a stone placed close to or inside the enemy's sphere of influence, which achieves neither (1) nor (2), and which must escape to the center in order to survive.