Introducing Three Methods to Analyze Board Positions (Part 2 of 2)

*This article was updated for length and clarity on certain cultural references. For the original article, please refer to https://www.1200igosharing.blog/en/post/analyzing-methods-in-go

Continuing from Part 1 of the previous article ( https://www.1200igosharing.blog/en/post/threemethodstoanalyzeboardpositions), we now introduce two more methods to analyze board positions.

Method 2: Tewari (i.e. What if the sequence of moves was rearranged?)

Returning to Board Position #1, let’s analyze it using the second method.

Black’s move: If we imagine that Black’s stone at A is at B (star position) instead...

We can easily see that the bottom right corner can be invaded at 3-3 point, so Black would need an extra stone to reinforce the corner and prevent the invasion.

However, returning to Board Position #1 where black has a stone at the komoku (3-4 point), can white can still invade at △? Check out the variations after black responded at A and B. (After choosing A or B on the board, press > button)

In both variatins, white can manage to live in the corner comfortably. What does this all mean?

Regardless of having a black stone at star or komoku, the corner is still open for invasion, so the value of defending the 3-3 invasion is high.

Thus, while black’s extension at point B may not seem efficient at first glance, the Tewari Method can help players understand its value.

Lastly, we discuss the third analysis method:

Method 3: Stones’ Efficiency

Returning to Board Position #1, by reinforcing the lower right corner at B, Black can also weaken White’s stone at R6. In other words, Black's extra move in the lower right corner serves a dual purpose of reinforcing the lower right while weakening the White stone. In contrast, reinforcing the upper right corner serves only one purpose. It does not weaken any White stones, and the right side is still open for invasion at Q12. Therefore, the move on the lower right is more efficient.

Board Position #3:

White played an unconventional opening. White invaded the 3-3 point at top right corner, but decided to ignore black’s extension (Q16) and play elsewhere. Black’s move: Which is larger, A or B?

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A, black’s move at A can significantly limit the effectiveness of White's 3-3 point invasion, making it valuable and efficient, in spite of forming an empty triangle.

Board Position #4:

Black to move:  Which is larger: A (knight’s move) or B (nobi)?

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The answer is B, but here comes a trickier question. Let’s move the Black stone at N17 (large knight) to O17 (small knight).

Board Position #5:

Same question: Which move is now larger for Black, A or B?

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This time the answer is A! The small knight (O17) can secure the corner more effectively than a large knight’s move or a jump against a 3-3 invasion (Check out the variations after A by the > button !) . Thus, judgment in Go can change depending on many factors, and we can only do our best to consider each board position independently.

Moreover, the analysis methods introduced above show that sometimes a seemingly slow and solid move (e.g. nobi, bend, or kosumi) can be more effective than an “efficient” move (small or large knight’s move or jump). This is a key point.

Please feel free to share screenshots from your recent games that show how these three methods would apply.