Just a thought on this.

Perhaps a bit late? Perhaps just a symptom of not yet having learned to watch liberties?

I think it makes sense for a strong player giving a beginning player a game at high handicap to warn "atari". Possibly also for a couple of beginners playing, say 20k or worse.

But probably out of place 10k or better.

The situation is different than chess because "check" isn't a warning as much as an announcement that only a move that deals with this would be legal. In go you are allowed to let the group be captured.

I'm not such a huge fan of this, it's probably the main thing that makes it difficult for beginners to learn to spot atari on their own.

In the long run, not being able to spot an atari is not going to remain one's biggest difficulty (and if it does, maybe it's time to take up something else). Most of us find it natural to want to save a stone, yet many of us initially find it a stretch to envision what could happen if the choose not to. Sure, beginners should learn to look for themselves, but there is quite a lot to look at, and it's good that they are looking in other places. To me, the niceness of informing a beginner not to overlook the atari outweighs the potential damage done.

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Patience, grasshopper.

I also don't like saying “Atari!” lest ppl believe this is a duty like saying “Check!” in Chess.

But sometimes I ask beginners who have just played a move while obviously not having seeing an Atari, “are you sure you want to place your stone there?”, without telling why (yes, I apparently have some sadistic facettes). If they insist, I ask “did you see that Atari?” w/o showing them where it is. If they don’t see it, I show them. Then I offer them to take back that move, if they wish to do so. Sometimes, if necessary because the situation is already unavoidable then, and if we can and wish, we go back a few moves to where it can be avoided, and usually we both learn something then.

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“The only difference between me and a madman is that I’m not mad.” — Salvador Dali ★ Play a slooooow correspondence game with me on OGS?

Okay, but how often is it a case of players being unable to spot the atari, versus not really looking for it in the first place?

It seems to me that only complete newcomers to the game have genuine difficulty seeing stones that are in atari (even when actively looking for them). I have to believe that most of the time, it is simply a case of a player not taking the time to look. A kind of carelessness that perhaps comes from trying to over-optimize one's play?

I believe(from my blunders, at 6k) that it's a matter of not actively looking for them. I don't agree with the phrase "over-optimize one's play", though. I think it's more of a case of cutting corners in reading, or a failure in pattern matching.

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a1h1 [1d]: You just need to curse the gods and defend.
Good Go = Shape.
Associação Portuguesa de Go

I meant over-optimizing in the sense that a player "cuts corners", as you say, on purpose in an attempt to save clock time by focusing on areas of the board believed to be more important. If this pruning of one's whole-board evaluation is an attempt at saving time, yet leads to missing or inadvertantly neglecting stones in atari, then I think the term over-optimizing is quite apt.

And failures of pattern matching seem irrelevent to me. One need not know a single thing about complex group patterns to count liberties and determine if any stones are in atari. After all, the definition of atari is that a stone or group has only one liberty remaining. How hard is it to count to one?

I think I see what you mean. My post was not that different from that, no.

Here, I disagree. One of the shortcuts that helps you improve is good pattern matching, to shortcut reading. Pattern matching doesn't always mean there's a complex group pattern around. Do you always read the Chapel?
If you do pattern matching well, you can skip a lot of lines in reading a position. However, if that pattern matching happens to fail to match a possible move as self-atari, only seeing a cut, or some other advantageous position, you might play it without reading/counting, and self-atari yourself before you've realized what you're doing.
I say "you" above in general. It's happened to me too much for my level, it might not happen to others.

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a1h1 [1d]: You just need to curse the gods and defend.
Good Go = Shape.
Associação Portuguesa de Go

I also don't like saying “Atari!” lest ppl believe this is a duty like saying “Check!” in Chess.[/quote]

The difference isn't so much that in chess a "duty". The difference is that in go one may allow a stone to be captured but in chess one may not ignore the king in check. Any move leaving the king in check is illegal. There are other fundamental differences. In chess there is no pass and having no legal move available is a draw (stalemate).

One way of learning to see the atari is from the beginning to develop the good habit of asking yourself every move: "What was the purpose of my opponent's last move?" This makes it pretty hard to miss an atari, and will also give you a better idea of what's going on in general on the board.

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Patience, grasshopper.

Just to make clear who said what

_________________
“The only difference between me and a madman is that I’m not mad.” — Salvador Dali ★ Play a slooooow correspondence game with me on OGS?

Sorry. That was an error in editing the nested quote. I was of course intending the line about saying "check" a duty in chess. Trying to say that not so much a duty as a necessity of the (other) rules of the game.

I perhaps should have made clearer for the benefit of those who were not at least fairly good chess players that the inability to pass determines the outcome (who wins) in many end game situations (chess end games). Not just "stalemate".

Okay, but even if one can't discern a strategic or tactical "meaning" behind an opponent's move, surely it takes nothing more than simple observation to determine if said move has put any stones in atari.

The problem seems to be what happens as stones in atari are left in atari, and as the game progresses, players forget about them and do nothing to refresh their memory. Or when they do try to refresh their cache (understanding of the board state), they take over-ambitious shortcuts and miss things. I can't help but think that many of these players just need to slow down and be more careful/attentive.

Seeing atari is the key to something like 50% of tsumego (and that percentage gets higher as the tsumego gets more difficult). "Shortage of liberties", which is a sort of fancy theme in tesuji/tsumego, happens when you cannot make the move you need because it puts your stones in atari.

Doing lots of tsumego helps cure this blindness. Even a lot of 30 kyu tsumego is about seeing obvious ataris 0 or 1 moves ahead. I wish I knew about this when I first started playing.

EDIT: Okay, to be honest, there is no complete cure.

I got the impression that the problem being described by the OP was failing to see stones currently in atari, not stones that could be in atari in the future. If I misunderstood him on this point, then that might explain why I am so puzzled by the phenomenon.

maybe you're so puzzled because you don't remember what it was like to be a beginner

The general phenomenon is not noticing (or having trouble seeing, or forgetting, or however you want to put it) that a certain string has N liberties in M moves... (1, 1) is just a special case of the general pattern, and is not necessarily more puzzling than (2, 1) or (1, 2).

I understand why beginners fail to see stones in immediate atari. They aren't accustomed to evaluating the entire board. How does this happen to anyone SDK or higher, except under extreme time pressure?

It happens to me on occasion still, as a mid SDK, usually because I have become overly focused on a specific goal and lose my objectivity for a moment. When my opponent doesn't respond as expected, I move to capitalise without taking the time to evaluate their move. It doesn't happen often, and usually is when I am tired, but I can't deny that it does.

I remember a recent game where I traded a 50 point centre away in exchange for a 10-15 point move on the edge in the endgame. At that point I couldn't resign for a while because I was too busy laughing at myself.

Yeah, stronger players never fail to spot ataris ...

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