What’s [in] a “moyo”?

I have been teaching youth to play GO for a while now… One perennial question that inevitably comes up is “What’s a ‘moyo'”—usually during a game review, at move 37 in the example below—and I try to tailor my answer to the student and his current understanding of the game.


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Simply put, a ‘moyo’ is a territorial framework of stones on the goban (game board). There is a lot that can (and has) be(en) said about implementing a ‘territorial’ strategy to gain advantage when playing Go. Several of the strongest professional players’ styles center (those in-the-know please excuse the pun) around this principle, viz. Takemiya-Masaki, Cho Chikun, Kato-Masao, Fujisawa-Shuko, and to a lesser extent the San-Ren-Sei (SRS) formation in the early stage of the game, by the player taking Black, in particular.

The most effective moyos tend to be formed as natural by-products of relatively conventional probing moves at the opponents’ positions rather than simply for their own sake; but, I fear that a discussion of ‘why’ that may be, would digress too far away from the topic at hand to discuss that in particular right now.

I think that many beginners, in an honest effort to play ‘properly’, tend to focus too much on local positions and tactics at the expense of seeing the whole board and adopting a global strategy… The most obvious example of this is the junior player, taking Black, who deftly repels all assaults against his corners, only to discover that White has (from Black’s perspective) inexplicably enclosed a vast unassailable tract of territory (moyo) in the center of the board! “But you said, ‘Playing in the center [at the beginning of the game] is inefficient!'” they complain… I then have to remind them that I probably gave that advice in response to their first play at the Tengen (center star point); and point out that their opponent hadn’t actually done that… at least not until much later in the game. At that point I usually trot out the mathematical analysis of the standard 19×19-line goban; and, explain the Line of Victory as lying between the 3rd and 4th lines from the edge of the board, since if each line is occupied by only one colour (concentric squares), the center-territory is 11×11=121 points, while the outside edge yields 136 points: a difference of only 15; so, that if the colour occupying the center had expanded by only 8 stones into the outer territory, it would win 129 to 128.

Beyond this, I encourage my students to consciously consider the configuration of the stones on the whole board before every move, and especially the ‘opportunity cost’ of playing locally vs. tenuki (‘playing away’), and conversely the worst-case-scenario of ignoring one’s opponent’s last move.  The motivation behind this is to foster a sense of ‘global awareness’—this has become easier in the 21st century with ecological rhetoric becoming an expression of Go Wisdom: “Think Globally, Act Locally.” The case in point is when ignoring a kakari (approach move) may cost you 15 points; but, by playing elsewhere you can secure a moyo of 50 points against meaningful reduction: when one is aware of the consequences, the choice becomes an easier one.

In my opinion, even if you are a Fighter rather than a Builder on the goban, you have to understand the principles that support both approaches to the game to be most effective. The Fighter needs to know where to attack a Builder so that he may not secure a large moyo; and conversely, the Builder needs to understand where an attack might be most detrimental to securing his moyo so that a compensatory or mitigating move may be made. The added advantage of understanding both basic strategic approaches is that you may be able to employ diametric tactics to great effect against another player who is more specialized.

“What’s in a moyo?”:  A microcosm of the fundamental thought processes necessary to foster optimal play. “How can I grasp those concepts?”: look for unbalanced decisions by both sides in games you review—you do review your games, don’t you?—and observe how badly things can go wrong… Experiment with alternatives, and weld the lessons learned into your brain with the searing pain of those failures, but have compassion for your opponents who have generously demonstrated such weaknesses  on your behalf.

©2010 Tyler Reynolds, GO for All Non-Exclusive Publication Rights granted to AllAboutGo.com

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4 Responses to “What’s [in] a “moyo”?”

  1. Paul says:

    I think this lesson is totally cool, and I especially like that mathematical example about 121 vs 136! Looking at the final game diagram, I think the moyo can be invaded, and lived in, especially by someone like Cho Chikun. I was just reading Yuan Zhou’s book on the style of Takemiya (from Slate and Shell). He points out that you have to be a really strong fighter to play moyo style, and you have to be willing to sacrifice all the easy territory in the corner and sides, in order to win with this style. For years I have been playing moyo style, without any clue what I was supposed to be doing. Recently I started learning about territorial style, and have been working on improving at that. Ultimately, you need to know both styles. Learning territorial first is probably a lot easier though, so I think I would recommend that for newer players ^_^

  2. Tyler says:

    Thanks, Paul! I’ve also been reading “Master Play: The Style of Takemiya” by Yuan Zhou lately… It will be the third book I review on my site from the Slate & Shell stable. I’ve just finished “The Go Consultants” by John Fairbairn & T. Mark Hall… but I digress.

    Of course my moyo could probably be invaded successfully by a professional (or even an advanced amateur, for that matter) 😀 However, I *do* tend to give player-specific advice, though; hence, my broad statement to the 20-kyu-rated player 😉

    I also have a soft-spot for moyo-style (“Builder”) play… I got a very high (245/300) San-ren-sei suitability score from Alex’s site, even though his other test evaluates me as “Flexible”. Coincidentally, I’ve previously been mistaken for Alex Dinerchtein at tournaments on more than one occasion—quite flattering, if somewhat embarrassing (because I don’t play as well)—he’s my Go ‘doppleganger’. 😉

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