GO, Board Game
Go is a strategic board game for two players. It is known as Weiqi in Chinese (Traditional Chinese: 圍棋; Simplified Chinese: 围棋), Igo or Go in Japanese (Kanji: 囲碁 or 碁), and Baduk or Paduk (Hangul: 바둑), sometimes Gi (기;棋 or 碁) in Korean. Go originated in ancient China, centuries before its earliest known references in 5th century BC writing. It is mostly popular in East Asia, but has nowadays gained some popularity in the rest of the world as well. Go is noted for being rich in strategic complexity despite its simple rules.
Go is played by two players alternately placing black and white stones on the vacant intersections of a line grid. The standard size of this grid is 19 × 19, although the rules of Go can be freely applied to any size: 13 × 13 and 9 × 9 are also popular choices for more simple and tactic-oriented games as well as a way to introduce Go to new players. The objective is to control a larger part of a board than the opponent as a result of having placed one’s stones such that they form territories that cannot be captured by the opponent. A stone or a group of stones is captured and removed if it has no empty adjacent intersections, the result of being completely surrounded by stones of the opposing color. The game ends and the score is counted when both players consecutively pass on a turn, indicating that neither side can increase its territory or reduce its opponent’s.
Despite the fact that Go originated in ancient China, it is commonly known in the West by its Japanese name, Go or igo (囲碁). This stems from the fact that pioneers like Oskar Korschelt and Edward Lasker learned of the game from Japanese sources. The Japanese name itself derives from the Japanese pronunciation of the Chinese characters for its Chinese name Weiqi (Traditional Chinese: 圍棋, Simplified Chinese: 围棋, pinyin: wéi qí). The characters 棋/碁 are variants, as can be seen in the Chinese Kangxi dictionary. The Chinese name roughly translates as “encirclement chess“, “board game of surrounding“, or “enclosing game“. The game’s ancient Chinese name is 弈 (pinyin: yì).
The Japan Go Association (Nihon Ki-in) has long played a leading role spreading Go outside East Asia, publishing the English-language magazine Go Review in the 1960s, establishing Go Centers in the US, Europe and South America , and often sending professional teachers on tour to Western nations for extended periods. As a result, many Go concepts for which there is no ready English equivalent have become known elsewhere by their Japanese names. In recent years however, many Chinese and Korean players have also begun teaching Western students. With this development, terms from Chinese and Korean are starting to be introduced in common usage.
In order to differentiate the game from the common English verb “go“, the game is sometimes spelt with a capital G; this convention is not however followed in most of the technical literature on the game. An alternative but uncommon spelling is Goe, proposed by the late Ing Chang-ki, a wealthy promoter of Go (particularly in Taiwan and the US and Europe), for the same reason. This spelling is not widely used outside events sponsored by the Ing foundation.
In many East Asian cultures, Go was considered one of the most important skills a civilized person could learn. This screen showing Chinese Go players in the Ming Dynasty was made by Kano Eitoku (狩野永徳) in the 16th century.
Some legends trace the origin of the game to legendary Chinese emperor Yao (2337–2258 BC) who designed it for his son, Danzhu — supposedly of limited intellect — to teach him discipline, concentration, and balance. Other theories suggest that the game was derived from Chinese tribal warlords and generals who used pieces of stone to map out attacking positions, or that Go equipment was originally a fortune telling device.
The earliest written references of the game come from the historical annal Zuo Zhuan, which describes a man in 548 BC who likes the game, and Book XVII of the Analects of Confucius, compiled sometime after 479 BC.
In China, Go was perceived as the popular game of the aristocracy while Xiangqi (Chinese chess) was the game of the masses. Go was considered one of the four cultivated arts of the Chinese scholar gentleman, along with calligraphy, painting and playing the guqin.
Go had reached Japan from China by the 7th century, and gained popularity at the imperial court in the 8th century. By the beginning of the 13th century, Go was played among the general public in Japan.
In 1603, Tokugawa Ieyasu created Japan’s first unified national government. Almost immediately, he appointed the then-best player in Japan, Honinbo Sansa, head of a newly founded Go academy (the Honinbo school, the first of several competing schools founded about the same time). These officially recognized and subsidized Go schools greatly developed the level of play, and introduced the martial arts style system of ranking players. Players from the four houses (Honinbo, Yasui, Inoue, Hayashi) competed in the annual castle games for status and the position of Godokoro, or minister of Go. Players like Honinbo Shusaku became national celebrities. A very famous game from this period is the Blood-vomiting game played between Honinbo Jowa (white) and Intetsu Akaboshi (black) on 27 June 1835. The government discontinued its support for the Go academies in 1868 as a result of the fall of the Tokugawa shogunate.
Historically, as with most sports and games, more men than women have played Go. Special tournaments for women exist, but until recently men and women did not compete together at the highest levels. However, the creation of new, open tournaments and the rise of strong female players, most notably Rui Naiwei, has in recent years legitimised the strength and competitiveness of emerging female players.
In 1996, NASA astronaut Daniel Barry and Japanese astronaut Koichi Wakata became the first people to play Go in space; Barry was awarded a Nihon Kiin honorary ni (2) dan rank for his “achievement”. Released in Japan during 1998, the manga (Japanese comic) and anime series Hikaru no Go popularized Go among the youth and started a Go boom in Japan and the rest of the world.
Nature of the game
In game theory terms, Go is a zero-sum, perfect information, partisan, deterministic strategy game, putting it in the same class as chess, checkers (draughts), and reversi (othello), although it is not similar in its play to these. Although the game rules are simple, the practical strategy is extremely complex.
The game emphasizes the importance of balance on multiple levels, and has internal tensions. To secure an area of the board, it is good to play moves close together; but to cover the largest area one needs to spread out, perhaps leaving weaknesses that can be exploited. Playing too low (close to the edge) secures insufficient territory and influence; yet playing too high (far from the edge) allows the opponent to invade. Many people find Go attractive for its reflection of the conflicting demands of real life.
It has been claimed that Go is the most complex game in the world because of its vast number of variation in individual games. Its large board and lack of restrictions allow great scope in strategy and expression of players’ individuality. Decisions in one part of the board may be influenced by an apparently unrelated situation in a distant part of the board. Plays made early in the game can shape the nature of conflict a hundred moves later.
The game complexity of Go is such that describing even elementary strategy fills many introductory books. In fact, numerical estimates show that the number of possible games of Go far exceeds the number of atoms in the known universe. Go strategy and tactics gives a very brief introduction to the main concepts of Go strategy.
It is possible to play Go with a simple paper board, and coins or plastic tokens for the stones. More popular midrange equipment includes cardstock, laminated particle board, or wood boards with stones of plastic or glass. More expensive traditional materials are also still used by many players.
The traditional Go board (qi pan in Chinese and goban in Japanese) is solid wood, from 10 to 18 cm thick. In Japan it is preferably made from the rare golden-tinged Kaya tree (Torreya nucifera), with the very best made from Kaya trees up to 700 years old. More recently, the California Torreya (Torreya californica) has been prized for its light color and pale rings, as well as its less-expensive and more readily available stock. Other woods often used to make quality table boards include Hiba (Thujopsis dolabrata), Katsura (Cercidiphyllum japonicum), Kauri (Agathis), and Shin-Kaya (Spruce). So-called Shin Kaya is a potentially confusing merchant’s term: shin means “new” and thus “shin kaya” is best translated “faux kaya” — the woods so described are biologically unrelated to Kaya.
In the Japanese style, stones (go-ishi) are kept in matching solid wood bowls (go-ke), and are made of clamshell (white) and slate (black). The classic slate is “nachiguro stone” mined in Wakayama prefecture and the clamshell from the Hamaguri clam. However, due to a scarcity in supplies, clamshells are being harvested from Mexico. The natural resources of Japan have been unable to keep up with the enormous demand for the native clams and slow-growing Kaya trees; both must be of sufficient age to grow to the necessary size, and they are now extremely rare at the age and quality required, raising the price of such equipment tremendously.
In China the game is traditionally played with yunzi stones, which are single convex (i.e. flat on one side). The stone comes from Yunnan province. Historically, the most prized stones were made of jade; often given to the reigning emperor as a gift.
In clubs and at tournaments, where large numbers of sets must be maintained (and usually purchased) by one organization, expensive traditional sets are not usually used. For these situations, table boards (of the same design as floor boards, but only about 2–5 cm thick and without legs) are used, and the stones are made of glass rather than slate and shell. Bowls are often plastic if wooden bowls are not available. Plastic stones are also used.
Traditionally, the board’s grid is 1.5 shaku long by 1.4 shaku wide (455 mm by 424 mm) with space beyond to allow stones to be played on the edges and corners of the grid. This often surprises newcomers: it is not a perfect square, but is longer than it is wide, in the proportion 15:14. The reason for this is that when the players sit at the board, the angle at which they view the board gives a foreshortening of the grid; the board is slightly longer between the players to compensate for this.
Traditional stones are made so that black stones are slightly larger in diameter than white; this is to compensate for the optical illusion created by contrasting colors that would make equal-sized white stones appear larger on the board than black stones.
The bowls for the stones are of a simple shape, like a flattened sphere with a level underside. The lid is loose-fitting and is upturned before play to receive stones captured during the game. The bowls are usually made of turned wood, although small lidded baskets of woven straw are a cheaper alternative from China.
The traditional way to place a Go stone is to first take a stone from the bowl, gripping it between the index and middle fingers, and then place it directly on the desired intersection. It is best to take only one stone at a time as you decide where best to play. It is permissible to strike the board firmly to produce a sharp click. Many consider the acoustic properties of the board to be quite important. The traditional goban will usually have its underside carved with a pyramid called a heso recessed into the board. Tradition holds that this is to give a better resonance to the stone’s click, but the more conventional explanation is to allow the board to expand and contract without splitting the wood. In theory, the wood never fully dries, so fully sealing it threatens warping in varying conditions. The heso allows the board to breathe.
Their respective liberties are shown with dots. Note that liberties are shared among all the stones of a unit. If White plays where his two units share a liberty, they will be connected into one.
If white plays at A, the black unit loses its last liberty, and is captured and removed from the board.
Two players, Black and White, take turns placing a stone (game piece) on a vacant point (intersection) of a 19 by 19 board (grid). Black moves first. Other board sizes such as 13×13 and 9×9 may be used for teaching or quick games, but 19×19 is the standard size. Once played, a stone may not be moved to a different point.
A vacant point adjacent to a stone is a liberty for that stone.
Adjacent stones of the same color form a unit (also called a group) that shares its liberties in common, cannot subsequently be subdivided, and in effect becomes a single larger stone. Only stones connected to one another by the lines on the board create a unit.
Units may be expanded by playing additional stones of the same color on their liberties, or amalgamated by playing a stone on a mutual liberty of two or more units of the same color.
A unit must have at least one liberty to remain on the board. When a unit is surrounded by opposing stones so that it has no liberties, it is captured and removed from the board.
If a stone is played where it has no liberties, but it occupies the last liberty of one or more opposing units, then such units are captured first, leaving the newly played stone at least one liberty.
“Ko rule”: A stone cannot be played on a particular point, if doing so would recreate the board position that existed after the same player’s previous turn.
- A player may pass instead of placing a stone, indicating that he sees no way to increase his territory or reduce his opponent’s territory. When both players pass consecutively, the game ends and is then scored.
A player’s score is the number of empty points enclosed by his stones plus the number of opposing stones which he has captured. Points which are occupied by stones do not count for scoring purposes. The player with the higher score wins. (Note that there are other rule sets that count the score differently, yet almost always produce the same result.) For a more detailed treatment, see Rules of Go.
This is the essence of the game of Go. The risk of capture means that stones must work together to control territory, which makes the gameplay very complex and interesting.
Go allows one to play not only even games (games between players of roughly equal strength) but also handicap games (games between players of unequal strength). Without a handicap, even a slight difference in strength will generally be decisive.
Game 1 of the 2002 LG Cup final between Choe Myeong-hun (White) and Lee Sedol (Black) at the end of the opening stage; white has developed a great deal of potential territory, while black has emphasized central influence.
Optional Go rules may set the following:
compensation points, almost always for the second player, see komi;
compensation stones placed on the board before alternate play, allowing players of different strengths to play competitively (see Go handicap for more information);
- “superko”: the ko rule (a move must not recreate the previous position) is extended to disallow any previous position. This prevents complex repetitive situations (“triple ko”, “eternal life”, etc.) from cycling indefinitely.
Basic strategic aspects include the following:
Connection: Keeping one’s own stones connected means that fewer groups need defense.
Cut: Keeping opposing stones disconnected means that the opponent needs to defend more groups.
Life: This is the ability of stones to permanently avoid capture. The simplest way is for the group to surround two “eyes” (separate empty areas), so that filling one eye will not kill the group and therefore be suicidal.
Death: The absence of life coupled with the inability to create it, resulting in the eventual removal of a group.
Invasion: Setting up a new living position inside an area where the opponent has greater influence, as a means of balancing territory.
- Reduction: Placing a stone far enough into the opponent’s area of influence to reduce the amount of territory he/she will eventually get, but not so far in that it is cut off from friendly stones outside.
The strategy involved can become very abstract and complex. High-level players spend years improving their understanding of strategy.
Concepts and philosophy
Go is not easy to play well. With each new level (rank) comes a deeper appreciation for the subtlety and nuances involved, and for the insight of stronger players. The acquisition of major concepts of the game comes slowly. Novices often start by randomly placing stones on the board, as if it were a game of chance; they inevitably lose to experienced players who know how to create effective formations. An understanding of how stones connect for greater power develops, and then a few basic common opening sequences may be understood. Learning the ways of life and death helps in a fundamental way to develop one’s strategic understanding of weak groups. It is necessary to play some thousands of games before one can get close to one’s ultimate potential Go skill. A player who both plays aggressively and can handle adversity is said to display kiai or fighting spirit in the game.
Familiarity with the board shows first the tactical importance of the edges, and then the efficiency of developing in the corners first, then sides, then centre. The more advanced beginner understands that territory and influence are somewhat interchangeable — but there needs to be a balance. It is best to develop more or less at the same pace as the opponent in both territory and influence. This intricate struggle of power and control makes the game highly dynamic.
Often, a comparison of Go and chess is used as a parallel to explain western versus eastern strategic thinking (despite the fact that both Go and the original forms of chess have Asian origins). Go begins with an empty board. It is focused on building from the ground up (nothing to something) with multiple, simultaneous battles leading to a point-based win. Chess, one can say, is in the end centralised, as the predetermined object is to kill one individual piece (the king). Go is quite otherwise: individuals are only significant as they join or help determine the fate of larger forces, and what those are is worked out only as the game proceeds.
A similar comparison has been drawn among Go, chess and backgammon, perhaps the three oldest games that still enjoy worldwide popularity. Backgammon is a “man vs. fate” contest, with chance playing a strong role in determining the outcome. Chess, with rows of soldiers marching forward to capture each other, embodies the conflict of “man vs. man.” Because the handicap system tells each Go player where he/she stands relative to other players, an honestly ranked player can expect to lose about half of his/her games; therefore, Go can be seen as embodying the quest for self-improvement — “man vs. self.”
Psychology of Go
A recent review of literature by Gobet, de Voogt & Retschitzki (2004)  shows that relatively little scientific research has been carried out on the psychology of Go, compared to other traditional board games such as chess and mancala games. Given the large search tree, knowledge and pattern recognition seem to be more important than look-ahead search. A study of the effects of age on Go playing  has shown that decline is milder with strong players than with weaker players. According to the review of Gobet and colleagues, the pattern of brain activity observed with techniques such as PET and fMRI does not show large differences between Go and chess, probably due to the fact that both games engage pattern recognition mechanisms. On the other hand, a study by Xiangchuan Chen et. al.  showed greater activation in the right hemisphere among Go players than among chess players, which suggests that Go calls upon para-rational and intuitive functions more. There is some evidence to suggest a correlation between playing board games (including Go) and the prevention of Alzheimer’s disease and dementia. 
Go poses a daunting challenge to computer programmers. While the strongest computer chess software has defeated top players (Deep Blue beat the world champion in 1997), the best Go programs routinely lose to talented children. The best computer Go software manages to reach consistently only the range 4-6 kyu level. Many humans have achieved this level by studying and playing regularly for less than one year. Many in the field of artificial intelligence consider Go to be a better measure of a computer’s capacity for thought than chess.
The reasons why computer programs do not play Go well are attributed to many qualities of the game, including:
The area of the board is very large (more than five times the size of a chess board). Throughout most of the game the number of legal moves stays at around 150–250 per turn, and rarely goes below 50 (compare chess, where the average number of moves is 37 ). Because a computer must consider every possible legal move in each ply (player turn), its ability to think ahead is sharply reduced when there are a large number of possible moves.
Unlike most games based on capture, where the game becomes simpler over time as pieces disappear (e.g. chess, checkers) , in Go, the game becomes progressively more complex as a new piece appears every move.
Unlike other games, a material advantage in Go does not mean a simple way to victory, and may just mean that short-term gain has been given priority.
The non-local nature of the ko rule has to be kept in mind in advanced play.
- There is a very high degree of pattern recognition involved in human capacity to play well.
The computer is a useful tool to support Go learners and players. Many Internet-based Go servers allow access to competition with players all over the world. Such servers also allow access to professional teaching, with both teaching games and interactive game review being possible. Electronic databases can be used to study life and death situations, joseki, fuseki and games by a particular player. The Internet also contains Go websites with material on various topics ranging from instruction to historical/cultural/scientific essays, information about top players, song parodies and more.
There are many variations on the basic game of Go. Many of the modern variants are purely for fun, but some were invented with a specific purpose in mind. For example, capture Go is used for introducing the game to beginners, whilst rengo (paired Go) aims at the promotion of the game amongst women. There are also historical regional variations that have now fallen out of fashion, such as Sunjang Baduk and Tibetan Go. A slightly modified version of Go is played in school at the back of mathematic exercise book (using its grid) using no more than red and blue pen. It is called Kepong, meaning to surround/to siege in Malay.
Go played using people wearing hats (black or white) in place of stones (black or white) on a grid laid out in the grass.
There are some instances in modern culture where Go and its strategies have been used as a literary concept, such as theme. For example, the 1979 novel Shibumi by Trevanian, centers around the game and uses Go metaphors. Go symbolism is used in the Chung Kuo series of novels, and Rick Cook‘s Limbo System. Other novels that have centered on the game include the Prix Goncourt des Lycéens and Kiriyama Prize winner The Girl Who Played Go by Shan Sa, Nobel prize-winner Yasunari Kawabata‘s The Master of Go, Sung-Hwa Hong’s First Kyu, Scarlett Thomas’s PopCo, and Jean-Jacques Pelletier‘ s Blunt: Les Treize Derniers Jours.
Gilles Deleuze and Felix Guattari use Go in their work A Thousand Plateaus as a model of what they call the war machine, something that eradicates the intrinsic properties a state apparatus forces upon its subjects. They contrast Go with chess, the latter having pieces with inherent, coded structure while Go is liberated from these restrictions.
In Go, one’s rank indicates one’s playing strength. The difference between each amateur rank is one handicap stone or about a ten point difference in score while for the professional ranks the difference is roughly 1 stone for every three ranks. For example, if a 5k played a game with a 1k where the 1k gave four handicap stones, the game would be about even whereas if a 9p played a 3p, he would give two handicap stones for a game where both have equal chances. The professional grades partly overlap the amateur dan grades. If an amateur does not know his/her rank then he/she is probably no better than 10 kyu.
The rank system comprises, from the lowest to highest ranks:
|Rank Type||Range||Skill Level|
|Double-digit kyu (級,급) (geup in Korean)||30–20k||Beginner|
|Double-digit kyu||19–10k||Casual player|
|Single-digit kyu||9–1k||Intermediate amateur|
|Amateur dan (段,단)||1–7d (where 8d is special title)||Advanced amateur|
|Professional dan (段,단)||1–9p (where 10p is special title)||Professional|
 Time control
- For more details on this topic, see time control.
A game of Go may be timed, using a game clock. Formal time controls were introduced into the professional game during the 1920s, and were controversial. Adjournments and sealed moves began to be regulated in the 1930s. Time control systems adapted to Go are often called byoyomi, something of a misnomer. Amateur Go tournaments use a number of different time control systems. All common systems envisage a single main period of time for each player for the game, but they vary on the protocols for continuation (in overtime) after a player has finished that time allowance. The top professional Go matches have timekeepers so that the players don’t have to press their own clocks.
Two widely used time control methods that are associated with Go are:
Standard byoyomi: After the main time is depleted, a player has a certain number of time periods (typically around thirty seconds). Using up the last period means that the player has lost on time.
- Canadian byoyomi: After using all of his/her main time, a player must make a certain number of moves within a certain period of time — for example, twenty moves within five minutes. If the time period expires without the required number of stones having been played, then the player has lost on time.
 Top players
- Main article: Go players
Although the game was developed in China, the establishment of the Four go houses by Tokugawa Ieyasu at the start of the 17th century shifted the focus of world go to Japan. State sponsorship, allowing players to dedicate themselves full-time to study of the game, and fierce competition between individual houses resulted in a significant increase in the level of play. During this period, the best player of his generation was given the prestigious title Meijin (master) and the post of Godokoro (minister of go). Of special note are the players that were dubbed Kisei (Go Sage). The only three players to receive this honor were Dosaku, Jowa and Shusaku, all of the house Honinbo.
After the end of the Tokugawa Shogunate and the Meiji Restoration period, the go houses slowly disappeared and in 1924 the Nihon Kiin (Japanese Go Association) was formed. Top players from this period often played newspaper sponsored matches of 2-10 games . Of special note are Go Seigen (born Wu Qingyuan, China), who scored an impressive 80% in these matches, and Kitani Minoru, who dominated matches in the early 1930’s. These two players are also recognized for their groundbreaking work on new opening theory (Shinfuseki).
For much of the twentieth century, Go continued to be dominated by players trained in Japan. Notable names including Sakata Eio, Rin Kaiho (born Lin Haifeng, Taiwan), Kato Masao, Kobayashi Koichi and Cho Chikun (born Cho Ch’i-hun, South Korea) . As these names show, top Chinese and Korean talents would sometimes move to Japan because the level of play there was high and funding was more lavish. One of the first Korean players to do so was Cho Namchul, who studied in the Kitani Dojo 1937-1944. After his return to Korea, the Hanguk Kiwon (Korean Go Association) was formed and caused the level of play in South Korea to rise significantly in the second half of the twentieth century. In China, the game suffered from the Cultural Revolution (1966-1976), but quickly recovered in the last quarter of the twentieth century, bringing Chinese players like Nie Weiping and Ma Xiaochun on par with their Japanese and Korean counterparts
With the advent of major international titles from 1989 onward, it became possible to more accurately compare the level of players from different countries. Korean players like Lee Chang-ho, Cho Hunhyun, Lee Sedol and Park Young-Hoon dominated international go and won an impressive number of titles. Several Chinese players also rose to the top in international go, most notably Ma Xiaochun, Chang Hao and Gu Li. Japan currently lags behind in the international go scene.
The level in other countries has traditionally been much lower, except for some players who had preparatory professional training in Asia. Knowledge of the game has been scant elsewhere, for most of the game’s history. A German scientist, Oscar Korschelt, is credited with the first systematic description of the game in a Western language in 1880; A famous player of the 1920s was Emanuel Lasker, a former world chess champion during that time.. It was not until the 1950s that more than a few Western players took up the game as other than a passing interest. In 1978, Manfred Wimmer became the first Westerner to receive a professional player’s certificate from an Asian professional Go association. In 2000 a Westerner, Michael Redmond, finally achieved the top rank awarded by an Asian Go association, 9 dan. In total, as of 2007, only 8 non-Asian go players have ever turned professional.