Movatterモバイル変換


[0]ホーム

URL:


Jump to content
WikipediaThe Free Encyclopedia
Search

Go opening

From Wikipedia, the free encyclopedia
(Redirected fromGo opening theory)
Initial moves of a Go game
icon
This articleneeds additional citations forverification. Please helpimprove this article byadding citations to reliable sources. Unsourced material may be challenged and removed.
Find sources: "Go opening" – news ·newspapers ·books ·scholar ·JSTOR
(January 2021) (Learn how and when to remove this message)
Part of a series on
Go
Game specifics
History and culture
Players and organizations
Computers and mathematics

AGo opening is the initial stage of a game ofGo. On the traditional19×19 board the opening phase of the game usually lasts between 15 and 40plies.[citation needed] There is some specialised terminology for go openings. The precise meanings ofJapanese language terms are often misunderstood.

Ago whole-board opening refers to an opening sequence of plays, almost always laid out the standard19×19 go board. Because of the symmetry of the board (eight-fold), there are certain conventions about displaying opening moves traditional inJapan. These do not necessarily apply inChina orKorea, but naturally in speaking of an 'opening' one never needs to distinguish openings related by symmetry.

The Japanese term for the opening phase of the game isjoban, but this is not used in English. Instead it is very common to usefuseki, a Japanese term that has a literal meaning of 'scattering of stones'. This really refers, therefore, to the way the initial plays are distributed around the sides and corners. If the game begins just in one corner, which is rare for high-level play but more common with novices, this is not reallyfuseki. Also,fuseki may be commonly used as a description for the pattern adopted by Black, the first player, for example, for Black 1-3-5. This ignores White 2 and White 4, and so is really a name for a side formation (for example,Chinese opening) or perhaps a diagonal formation (for example,tasukiboshi, where Black 1 and Black 3 are at 4-4 points in the north-east and south-west corners). The Korean-language term equivalent tofuseki isposeok.

There are alsogo corner openings. There are many thousands of these standard variations known, related to developments in just one 10×10 corner of the board. In English, they are almost always calledjoseki;joseki is not asynonym ofcorner opening, but ofstandard sequence. The literal meaning in Japanese is ofset (i.e., fixed or settled)stones. There arejoseki in Go that do not relate to the corner openings. The Korean term equivalent tojoseki isjeongseok, often transliteratedjungsuk.

In Japanese the 10-10 point on the board (i.e. the center) is calledtengen. An opening play attengen is a kind of experimental opening, and has at times in history been controversial. It may lead to what is calledmirror go, in Japanesemanego, in which Black imitates White by playing diagonally opposite with respect to the centre stone. There is another style, also called mirror go, where from the beginning of the game White imitates Black in a diagonally-opposite way. The first kind was interesting, for strong players, before the introduction ofkomidashi, i.e. compensation points for second play. The second kind became interesting onlyafter the introduction ofkomidashi.Go opening strategy is the strategy applied in Go opening.

There are some conventional divisions that are applied. Firstly there is the distinction that may be drawn betweengo opening theory, the codified variations that resemblechess openings in the way that they occur repeated in games, andgo opening principles. Since there is great freedom of choice, the fundamental opening principles are more useful for all players before they reachdan player level.

Basic principles

[edit]

Examples of principles that are generally useful are comments such as 'corner-side-centre', which says that the corner areas of the board are more valuable than the sides (points near an edge but away from the corners). Occupying points in the centre may be good for early fighting, but these points are weaker from the aspect of developing one's territory.

Developments over the last century

[edit]

The opening strategy in Go can be said to have undergone some major changes in the twentieth century. Not only have newjoseki been developed, but some important shifts in thinking have occurred. For example:

  • from 1900 to 1930, the strategy was traditional, the so-calledShusaku style
  • in 1933 and for a few years afterwards, a very different and experimental style calledshinfuseki dominated professional go, at least for the younger players
  • from around 1936, there was a compromise of styles,sugou fuseki, which mixed some of the more successful ideas fromshinfuseki with older techniques for a more balanced approach, forming the basis of modern professional play
  • the introduction ofkomidashi of 4.5 points in most top tournaments of the 1950s led to a tighter, territorial style for Black, for example inSakata Eio, with greater use of the3-3 point for White also.
  • theChinese opening dominated thinking from the early 1970s, and many further ideas were tried, for example themini-chinese formation which is a side opening, rather than a corner opening or whole-board opening
  • the entry ofSouth Korean professionals into international competitions in the early 1990s saw the use of 'prepared variations' of whole-board openings, in a way not seen before.

Contemporary ideas

[edit]

Contemporary Go opening strategy is more complicated than the old corner opening/whole-board opening distinction suggests. The4-4 point is used by professionals in about 70% of corners. Corner openings for the 4-4 point are still being developed, but it is more accurate to say that almost all contemporary opening theory is implicated in the patterns around the 4-4 point.

Fuseki

[edit]
Main article:Fuseki

The Japanese termfuseki is sometimes taken as synonymous with 'whole-board strategy'. More accurately, it means the 'scattering' or thin distribution of stones that occurs in the early part of the game.In the game ofGo,opening theory is the strategy of where, why, in what order, and in whatshapes the first several moves are played in Go opening.[1] Themiddle game typically begins once the basic foundational areas calledframeworks[2] are established and "fighting" begins.[3]

The opening is conceptually and traditionally divided for study into the sequences that arewhole board openings[4] and those that arecorner openings.[5] Each type constitutes a series of plays which have been studied for their balance (with the other) as well as for countermoves.

For a standard board,[6] the most basic single concept for the opening is thatplays in the corners are more efficient for making territory than plays on the sides or in the center.

Only a relatively small proportion of openings have a recognised name. These include theThree stars opening (sanrensei),Two stars opening (nirensei),"Pinwheel" or Shusaku opening andChinese opening (Chinese fuseki). To be more precise, these are names for the moyo (framework) formations which Black makes on one side of the board. Since White has a choice of perhaps two dozen legitimate variations on the other side, these are in fact large complexes of openings.

The Chinese opening has an intricate history. According to several historical accounts (both Chinese and Japanese), it was actually first developed by Japanese players, but later was heavily researched and developed by Chinese players. It was very popular from about 1970 onwards, and has by Go standards a thoroughly-researched theory.

Jōseki

[edit]
Main article:Jōseki

Joseki are "sequences" of moves which have been

  • played and documented in high-level play, and
  • studied and deemed as consisting of optimal (balanced) moves for both sides.

Joseki is a Japanese word (定石) (Koreanjeongseok), wherejo (定) means "fixed" or "set", andseki (石) means stone(s). It thus literally means "set stones", as in "set pattern". Variations are shown to lead to different positional advantages and disadvantages for the two players in certain overall game situations. If Black and White both play thejoseki correctly, they should achieve a balanced result within that particular corner; neither should have a large advantage, unless the opponent makes a mistake.[7]

"Balance" typically refers to an equitable trade-off between securing territory in the corner versus making goodthickness toward the sides and center. The assessment also takes into account who started and ended the corner sequence: if Black has played one more stone than White in the corner, for example, Black's result should be objectively better than White's, to reflect the extra investment of a play.

In application these concepts are in fact very dynamic, and oftenjoseki are deviated from depending on the needs of the situation, and the opportunities available. While learningjoseki is a tool to defend against a local loss, players can seek to take advantage by deviating from thejoseki, or "pausing" it.

Usuallyjoseki as a term (in literature in English) is applied to a set sequence happening in one corner in the opening stage. These sequences are not the only set sequences in the game, however. There are alsojoseki seen in the middle game: these include standard follow-ups to earlierjoseki. Other examples are common techniques for invading or reducing frameworks. Learning to apply these so-called "middle game joseki" is one of the steps to becoming strong.[8]

The current body made up ofjoseki is not fixed, but consists of patterns that have gained acceptance in professional games. That is, they form a consensus judgement that might change in the future, or with certain caveats.

Hence the basic definition may be misleading for new players in that joseki can be misconstrued as foolproof and unalterable, and are otherwise optimal for all situations. Some joseki are in fact useful only for study within an artificially confined corner, and in real play are only considered good form when used in proper combination with other plays on the board (i.e. other joseki and fuseki moves).

Knowing a particularjoseki simply means that one knows a sequence of moves, resulting in a balance or fair trade-off between their positions. This is in practice much easier than appraising howjoseki relate to the rest of the board—henceknowledge of joseki is regarded as shallow, when compared with the ability to integrate a strategy into a complex game landscape.

There is ago proverb that states that "learningjoseki loses two stones in strength," meaning that rote learning of sequences is not advantageous. Rather learningfromjoseki should be a player's goal. Hence the study of joseki is regarded as a double-edged sword and useful only if learned not by rote but rather by understanding the principles behind each move.

Everyjoseki should be used as a specific tool that leaves the board in a particular shape. Just as using an improper tool in machinery can be devastating, choosing the wrongjoseki can easily be worse than improvising one's own moves.

In his bookA Way of Play for the 21st Century,Go Seigen compared choosing the proper joseki to choosing the proper medicine—pick the right one, and you feel better. Pick the wrong one and you die.(par.)Rui Naiwei similarly remarked thatplaying joseki is easy [but] choosing the right one [in a game] is hard.(par.)

Ajoseki may fall out of use for various reasons, some of which may often seem minor to the amateur player, and professionals may consider one variation suboptimal for a very specific reason.

There is no definitive guide to what isjoseki; the situation withjoseki dictionaries is similar to that of natural language dictionaries, in that some entries are obsolete and the listing is not likely to be complete. Studyingjoseki is only an important part of developing one'sstrength as a player at some levels; the study oflife and death and middle-game fighting are considered to be more important.

Concepts

[edit]

Opening theory is less dominant in terms of study for those wanting to reach a good amateurlevel, than inchess orshogi. It is, however, an important component of Go knowledge, though there is no single, codified source for it.[9]

The standard sequences for thejoseki in many cases come to a definite end, after which both players should move elsewhere. In some cases a sharp local struggle breaks out, which neither player should neglect. For those cases, the result of the opening may develop out of a 10×10 corner area into the rest of the board. Analysis without taking into account what other stones are in place then becomes somewhat meaningless. The longest 'book' corner openings are about 50-ply.[10]

Most corner openings do not have special or picturesque names. A few that do are known by Japanese names: thetaisha, thenadare (avalanche), theMagic sword of Muramasa. These are among the most complex, and are contraindicated for novices.

History

[edit]

Go openings have been studied in depth for many centuries, and center upon concepts of finding balance with the opponent. Because black moves first, opening moves for black are based on the concept of exploiting that first-move advantage (along withsente) to gaininfluence (or strength) and thus establish areas of territory.There is no complete theory of go, simply because the number of possible variations makes any literal study impossible. Hence even the opening is subject to changes of fashion, and also some notable periods of innovation.

Certain professional players are known for their use of specific or innovative types of openings, and their ability to combine their use of those openings with other strengths in competitive play.

The 10-10 point

[edit]
Main article:List of Go games § The Game of the_Century

Go Seigen played his third move (Black 5) ontengen, in a 1933 game againstHoninbo Shusai, the top player of the time. Go lost the controversial four-month game, which was played over 14 sessions in aryokan in Tokyo from 16 October 1933 to 19 January 1934.[11][12]

References

[edit]
  1. ^The opening is normally around 20ply long.
  2. ^Framework in English translates tomoyo in Japanese.
  3. ^This occurs when moves directly attack an opponent'sweak groups, with the serious possibility of killing it.
  4. ^The Japanese termfuseki is also current in English.
  5. ^Joseki in Japanese, meaning 'set pattern', is current in English usage.
  6. ^I.e. a 19x19 linegoban; essentially no theory for smaller boards gets into print.
  7. ^On the other hand, the evaluation of the result as fair has to take into account bothwho started in the corner, andwho ended the sequence. The first player in a corner expects some advantage; the last player loses the initiative.
  8. ^SeeSakata Eio,The Midde Game of Go: Chubansen for examples. "Middle game joseki" may not correspond to any definite concept translated from the Japanese technical vocabulary, however, since they may simply be classified as known "techniques".
  9. ^There are 'joseki dictionaries' and 'fuseki dictionaries'. The largest joseki dictionaries contain around 50000 variations; the usual estimate is that a professional player would know about 10% of that number of corner opening lines. Fuseki dictionaries have never been produced in any comparable degree of comprehensiveness; the Large Fuseki Dictionary (布石大事典) of theNihon Ki-in has around 1000 representative openings.
  10. ^There are some localised variations of this length in thekado variation of thenikkentakabasami, and in thetaisha, where in fact ako fight may arise.
  11. ^"Game of the Century at Sensei's Library".
  12. ^"Game of the Century Poster - Go Seigen vs Honinbo Shusai". Archived fromthe original on 2010-02-19. Retrieved2019-12-07.
Overview
Equipment
Terms
Strategy and tactics
History
Competition
Games and matches
Art and media
Computers
Organizations
Other
Retrieved from "https://en.wikipedia.org/w/index.php?title=Go_opening&oldid=1316098066"
Category:
Hidden categories:

[8]ページ先頭

©2009-2025 Movatter.jp