Life In 19x19

Even pros are not immune to that disease: viewtopic.php?p=233171#p233171

In principle, one way to avoid that kind of accident is, at every stage of the endgame, read what happens when the opponent pushes in every hole, makes all possible ataris and fills all liberties. But that's theory...

thirdfogie wrote:In the 7 cases where I wedged, 2 were correct. In 2 of the other 5, the best move for white was actually a clamp. That discovery alone justifies the exercise.

Very good.

thirdfogie wrote:I don't regret spending time on the research, but it has now been overtaken by events. My opponent has access to these findings and has stopped playing wedges. He now favours lots of invasions on the first line, which are easier to read out. Meanwhile, I am blundering away won games by not counting liberties when tired near the end of the game. It is unclear how to cure that ill.

It doesn't hurt to start with the straightforward approach. Always count liberties. Even if that means doing less reading in the early and middle game. As a result you may make worse plays from time to time. But you won't throw away games from miscounting liberties late in the game. My guess is that you will win more games.

In addition, practice makes perfect. Your skill at counting liberties will improve, and will probably take less time as you get better at it.

Just had some thoughts on Uberdude's point about passive play. My thoughts are about defining such human concepts in terms of shape.

A definition of "passive" vs aggressive (or vs active) is probably about taking less risk with your own groups by playing close to them for safety, prioritising reinforcement as opposed to impact on the opponent or unoccupied areas). It is fairly independent of the component of quality/size of a move. But when it is a criticism, it generally means the opponent profits from it, either by taking a bigger move globally (since you didn't need to defend yet) or taking advantage locally. This case can be said to be that the descent allows black to seal off the upper right in sente, so the exchange seems timid.

Here I think thirdfogie describes the capture as passive since it removes the chance of the cutting stone escaping. Whereas descending plays more close to Black's area, which seems more confrontational at first sight. However, with some reading (since black playing on White's liberty shortage of L16 seems much less likely that using the N18 sente immediately), there is no chance of the cutting stone escaping if white plays descend.

In fact, compared to capturing, descending adds a second buffer zone between the cutting stone and Black's upper right (other than the capture move) making it more difficult for black to encroach.

Unfortunately this protection comes at a heavy price, namely the cost of another move given that white is forced to capture the stone anyway pretty much immediately.

Uberdude prefers to say the direct capture is not as passive. This is because the main line risks a ko, simply because Black's atari on the ko shape is not sente.

I'm sure this distinction between types of passiveness recurs throughout Go. It is related to concepts of gote no sente or sente no gote, or whether to defend a shape with one move or two.

.

Can this sort of analysis be done with other common words, such as light/heavy?

dfan wrote:

thirdfogie wrote:There is not enough material to draw any general conclusions. However, accurate reading always helps, and one should probably capture any cutting stone on the third line immediately if possible.

In these sorts of atari situations, I believe that in general stronger (let's say 1d) players are much more likely to just capture a stone, and weaker (let's say 5k) players are more likely to extend instead of taking the stone off the board, which looks more efficient but often leads to the opponent getting forcing moves later or having some aji still around. I think that it is a good instinct for players of our level to first consider making the capture, unless there is clearly zero aji.

The AI often plays on the 6th or 7th line instead of capturing a stone in a ladder because capturing is over concentrated

Yes, ladders are another story. All of my comments were referring to the decision between capturing a stone on the third line (by playing on the second line) or descending to the second line.