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Keshi Is Worth As Much As An Invasion
Path: GoProverbs   · Prev: PlayKikashiBeforeLiving   · Next: DontAttachWhenAttacking
Path: InvasionItinerary   · Prev: KeshiAndUchikomiReductionAndInvasionInGo   · Next: ErasureOrInvasion

    Keywords: Proverb

A keshi play, or "erasure", is a move made on the edge of an opponent's framework (moyo) or just outside it. The idea is to allow him some territory, but not that much. Typical keshis are the shoulder hit, the cap (boshi) and a play on the border of a central moyo.

An erasing move is often the smart choice for several reasons:

  • First, it is less risky than an invasion, especially when you don't have support in the area.
  • Second, while an invasion often permits the opponent to get outside thickness in exchange for losing some territory, a keshi move can help to build influence or contribute to a central moyo while keeping the opponent's area to manageable proportions. Look at it this way: if your keshi move reduces the enemy position by 7 points and gives you the chance to make central territory of about 8 points, then it is worth 15 points, which I'm sure you'll agree is not too shabby!
  • Third, many keshi moves such as the shoulder hit and boshi have more severe potential follow-ups, should opportunity arise.
  • Finally, it's often quite amazing just how much an enemy territory can be reduced by keshi.

I hope this helps :-) Tamsin (BGA 2 kyu)


(moved from TwoEyesCanDie: )

Jan de Wit: I've read somewhere (not on this site) that you need about twenty points of open space for an invasion to succeed. Is that true?

Stefan: It's among the proverbs on Jan van der Steen's site, as follows: "To invade, need 20 points in open area; otherwise, keshi is best." -- Yang Yilun, 7 dan pro


RafaelCaetano: Is the title really a proverb? Fujisawa says that a reduction is worth as much as a jump (i.e., an expansion), in the same way as a kakari is worth as much as a corner enclosure. And Yang's proverb seems to contradict the title.

Bill: Rafael, I have encountered many proverbs in English that I never heard of in Japanese. I usually take them cum grano salis. This one addresses a common failing of untutored amateurs, which is to invade too often. Actually, OC, sometimes a keshi is worth more than an invasion, sometimes an invasion is worth more.

Bob McGuigan: I think the title advice is also aimed at players who tend to over-estimate the value of a moyo and hence invade when erasing moves could be as or even more effective. As was pointed out earlier, erasing moves are often multi-purpose while invasions tend to have only one purpose. Another important point is that invasions tend to end in gote for the invader while erasure usually ends in sente.

Rafael: Bill, let me rephrase it. I don't care so much for the original language of the proverb, as long as it is sound advice. I'm too weak to say for sure but this "proverb" seems doubtful. I understand that when kakari and shimari are possible, usually both are good moves. Apart from Kajiwara, I've never heard "oh, this kakari is the losing move! Black must play shimari". Could you say the same about reduction vs. invasion?

Bill: No, Rafael, I can't say the same, because the invasion or kikashi of a moyo are (usually) mutually exclusive options for the same player. Typically one is better than the other. By contrast, when a player has the option of a kakari in one corner or a shimari in another, they are not mutually exclusive and are often miai. Still, the overall board position may make one better than the other. The difference can be fairly small. Kajiwara seems to have a tendency to exaggerate. ;-)

Bob, I like the page, my question is about the title and its promotion to a proverb.

Bob: I understand your point, Rafael. It makes me wonder how something gets the status of a proverb. We're aware that so-called proverbs have exceptions, so they aren't infallible guides to correct play. I guess something becomes a proverb if it is terse, conveys a useful guide to correct play, and has just a hint of wit. If it has had this status for decades it helps, too.

Calvin: I don't understand Bob's comment on how keshi moves are more likely to be multi-purpose. Can you provide an example that illustrates this flexibility? Are you referring to the fact that a cap, for example, can also threaten a group sometimes, or is it more than that?

Bob: Erasing moves on the edge of a moyo often help develop your own position while invasion moves create a weak group which must defend itself and are usually aimed just at destroying, not creating. That's the sort of thing I had in mind. As usual there are many example that contradict this but it is a useful way to think about things, in my opinion.



Path: GoProverbs   · Prev: PlayKikashiBeforeLiving   · Next: DontAttachWhenAttacking
Path: InvasionItinerary   · Prev: KeshiAndUchikomiReductionAndInvasionInGo   · Next: ErasureOrInvasion

This is a copy of the living page "Keshi Is Worth As Much As An Invasion" at Sensei's Library.
(OC) 2004 the Authors, published under the OpenContent License V1.0.