Anything other than a 1 moku is a loss.

[DrStraw]

Since writing this post, I've become an even firmer believer in the concept. ....

Well, if you were trying to win by a small margin then you played some pretty strange moves. Had your opponent not been so generous you would have lost by a lot. You played inferior moves and got away with them. If you really want to win my one point you need to make sure you are comfortably ahead entering the endgame and then count thoroughly enough to allow the opponent to make it close.

[Joelnelsonb]

It's a theoretical concept that is obviously very difficult for even the best to apply practically. None the less, I would imagine that if two of the best players in the world sat down to play, their thinking would be something like this:

Black moves...
White moves...
Both think: the games even good, so far so good.

Black moves...
White moves...
Both think: the games even good, so far so good.

etc...

Until:
Black moves...
White: Hey, he left a weakness (in the form of an over OR an underplay). I shall punish without leaving a weakness as well.
Black: Crap! he's got me... My only chance now is if he screws it up.

Black moves...
White moves...
Both think: white still wins by one...

Black moves...
White moves...
Both think: white still wins by one...

Eventually:
Black: Thank you for the game; well played!
white: Thank you.

[A game between to slightly weaker players would involve a moment when black says to himself " I will lose this game if I don't do something desperate".
Black moves...
White thinks "nice try, I could now blow you off the board, BUT, I'm already winning..."
White plays on as if black played normally in the best possible way.]

Oh and please don't interpret me as talking down to a 5 Dan! I'm simply putting forth an idea for scrutiny and correction as needed.

[DrStraw]

More likely:

Black: If I play this move then 20 moves later I will be in trouble so I better no play it.
White: Yes, just as I thought, he read the same 20 move sequence I did.

[skydyr]

A couple things:

First off, it's not necessarily due to overplay that you might be ahead by more than 1. Your opponent could have made a mistake, which happens quite frequently. More hypothetically, komi could be wrong..

Second, if you are in endgame, and you are losing, and playing the normal good endgame still results in your losing, the normal 'correct' move is wrong. Playing the normal move means that you have already conceded, and should resign. You need to play something different and complicated to give yourself a chance before you have none left. You may still lose, but at least you tried.

[quantumf]

The principle is perfectly sound, and I would say that's the way I play, and I speculate that that is how most players stronger than me play: balance aggressive attack with solid defence to ensure a win by a reasonable margin. The stronger you get the smaller a reasonable margin has to be. If sufficiently strong, then one point (or half a point) is probably enough.

The practical difficulty is that when we're weak, that margin has to be pretty enormous given the terrible moves we make. As a 2d, I'd probably aim for a 30 point margin in the early part of the game, reducing to about 10 as we enter endgame, and as an 8k, I'd suggest aiming for a 100 point margin, reducing to 50 in the endgame. Having said that, I do recall losing enormous groups as liberties ran out in then endgame when I was 8k, so this is a very rough heuristic. Playing for a 1 point win as an 8k is not meaningful, and probably not viable until you're at least 7d.

[Mike Novack]

This is silly, a misunderstanding of the goal. Let me restate what the correct goal should be:

If ahead, make the move with the greatest probability of ending up AT LEAST ONE move ahead at the end of the game.

That is NOT the same thing as "exactly one move ahead", and the probability for "at least one move ahead" can never be less than that for "exactly one move ahead" << because "at least one" contains "exactly one" >>

Understand? The probability of winning the game by exactly one move has to be inferior to winning by one move OR by two moves (etc.)

[Polama]

[A game between to slightly weaker players would involve a moment when black says to himself " I will lose this game if I don't do something desperate".
Black moves...
White thinks "nice try, I could now blow you off the board, BUT, I'm already winning..."
White plays on as if black played normally in the best possible way.]

To me, that's just hubris on White's part. Sacrificing points for simplicity is an important skill. But failing to take advantage of an error like that is sacrificing points and increasing complexity. When ahead, we balance gaining further advantages against making the game simpler. Sometimes we can increase the probability of a win by accepting a little more complexity but improving our margin, sometimes the opposite is true. But a move that gives up an opportunity for a better margin and a safer position is just a bad move. It may be a sociable move, to let the opponent save face or to keep our spouses from despairing and not playing with us anymore, but it's not a good Go move.

As for the trade-off between complexity and margin, Margin is more important when the uncertainty is high, complexity when the uncertainty is low. A professional with a lead late in the middle game can afford to sacrifice most of his lead for simplicity, because he can be confident in his ability to win a won game. When I have a lead late in the middle game, I have to be much more greedy about my advantages than the professional. Am I really leading? I've seen enough crazy tsumego to know that what I perceive as safe may be no such thing.

I feel like you're putting the cart before the horse. Because a professional can read accurately further and is surprised by less, the win-maximizing move will often be more conservative for them (although a move that gains points and simplifies is always worth taking). But I think that means we should work on our win-maximization and our reading so we approach the professionals skill, not play for 1 point wins as if we knew our leads in the middle game to that accuracy. A top professional can give an 1 dan 9 handicap stones, and I strive for that, but it doesn't mean I should give them 9 handicap stones now.

[Joelnelsonb]

I thought about this a lot today (while doing the most mundane, mind-numbing task ever at work) and I think I might be pushing a principle beyond it's limits. Think of this: if you were playing a game where its was coming into the endgame and you were ahead by around 20 points, you look over your position and see that there's not really anywhere for your opponent to break in and get something going. You feel safe that its in the bag, even if you wanted to let your ddk friend take over and finish it up. You then see that your opponent makes a slight endgame error that leaves one of his groups open to an attack. After reading it out a little, your next to certain you can kill him. However, you're also aware that on the off chance that he doesn't die, the failed attack would leave the board in such a position that you would now be vulnerable and at risk of losing the game. Do you attack? Why on earth would you, right? You've already won the game, no need to risk anything (Rich men shouldn't pick fights). So push this to the full extent and think about if you're ahead at anytime in the game by even a slight advantage, why be greedy and try to get more when you could play it safe the rest of the way and win by a small margin? The whole point isn't that you deliberately make "bad" moves in order to make it close but rather that you're sort of dancing with you opponent, playing off of whatever he goes for, just staying a little ahead the whole way. In making this a goal, my motivation is to better understand the whole concept of "exchange" and how to make even exchanges whenever needed, even when the advantages being exchanged are completely different from each other.

More theoretically speaking, I'll repeat what I've already said in the thread: The easiest and most fool-proof plan you can come up with to win is the one that allows your opponent as much as you can possible allow him to have, short of letting him win. Your opponent wants control of more than half the board. Your plan should be to let him have 180 points, while erring on the side of less than that.

[Bill Spight]

After reading it out a little, your next to certain you can kill him. However, you're also aware that on the off chance that he doesn't die, the failed attack would leave the board in such a position that you would now be vulnerable and at risk of losing the game. Do you attack? Why on earth would you, right?

For fun.

For honor.

To see if you are right.

[Shenoute]

I thought about this a lot today (while doing the most mundane, mind-numbing task ever at work) and I think I might be pushing a principle beyond it's limits. Think of this: if you were playing a game where its was coming into the endgame and you were ahead by around 20 points, you look over your position and see that there's not really anywhere for your opponent to break in and get something going. You feel safe that its in the bag, even if you wanted to let your ddk friend take over and finish it up. You then see that your opponent makes a slight endgame error that leaves one of his groups open to an attack. After reading it out a little, your next to certain you can kill him. However, you're also aware that on the off chance that he doesn't die, the failed attack would leave the board in such a position that you would now be vulnerable and at risk of losing the game. Do you attack? Why on earth would you, right? You've already won the game, no need to risk anything (Rich men shouldn't pick fights). So push this to the full extent and think about if you're ahead at anytime in the game by even a slight advantage, why be greedy and try to get more when you could play it safe the rest of the way and win by a small margin? The whole point isn't that you deliberately make "bad" moves in order to make it close but rather that you're sort of dancing with you opponent, playing off of whatever he goes for, just staying a little ahead the whole way. In making this a goal, my motivation is to better understand the whole concept of "exchange" and how to make even exchanges whenever needed, even when the advantages being exchanged are completely different from each other.

In your example, there is a risk of losing the game while in your theoretical development you only envision "playing safe and win by a small margin". I don't see how these two situations can be compared.

More theoretically speaking, I'll repeat what I've already said in the thread: The easiest and most fool-proof plan you can come up with to win is the one that allows your opponent as much as you can possible allow him to have, short of letting him win. Your opponent wants control of more than half the board. Your plan should be to let him have 180 points, while erring on the side of less than that.

While this might be true at the start of the game, I fail to see why this is the "easiest and most fool-proof plan" for us amateurs, whose games are riddled with mistakes on both sides*. There will be one (and probably more) moment during the game where you will end up being 20 points behind or 20 points ahead. What do you do then, resign in both cases?
Plus your plan presupposes that you are able to count the game very precisely, something that is incredibly hard to do in the middle game.

I followed this thread and, while I (think I) understand what your point is in theory, I also don't think it is applicable to real life go games.

*Even pros make mistakes that put them "many" points behind, what are their opponents supposed to do?

[Polama]

...You feel safe that its in the bag, even if you wanted to let your ddk friend take over and finish it up. You then see that your opponent makes a slight endgame error that leaves one of his groups open to an attack. After reading it out a little, your next to certain you can kill him. However, you're also aware that on the off chance that he doesn't die, the failed attack would leave the board in such a position that you would now be vulnerable and at risk of losing the game. Do you attack? Why on earth would you, right?

Of course. But on the other hand, if I win the attack and kill his group all my surrounding stones are now trivially alive. If I hold back my hand, it's entirely possible I miss some amazing tesuji as we fill in the dame and lose the game that way. I don't believe that the move that minimizes the margin is inherently the safest move. In your example of risky attack vs. safe defense, safe defense is better. But I think that's particular to the example, not a truism. There are plenty of cases where you have an easy kill, or a tortuous road to a single point victory.

...The whole point isn't that you deliberately make "bad" moves in order to make it close but rather that you're sort of dancing with you opponent, playing off of whatever he goes for, just staying a little ahead the whole way.

Exactly, you're playing off of what your opponent goes for.

http://senseis.xmp.net/?YiChangHo

Lee Changho is an interesting example. He rose to the top of the Go world using the style you advocate: Earning small advantages while conceding to the opponent's desires and simplifying, and then playing a precise endgame for the win. Then he switched to a tighter, more fighting style. Why?

The next generation of players came up studying him, and they figured out how to force the game into fights: how to create situations where a big fight was necessary. Lee Changho probably would have preferred his approach of conceding small battles and winning the war, but it wasn't working. So he adapted, and started preparing for the fight from the start of the game, because that's where it was headed.

Conceding points for simplicity when ahead is a powerful concept, I just don't think it's a universal. An opponent may very well be able to force you into a game deciding fight, where your advantage becomes a better position for the fight rather than a point lead. Whether a move decreases your margin, and whether a move simplifies the game, can be orthogonal.

[Mike Novack]

Look, this is analogous to a sailboat match race (race between two boats).

If the boat that is at the moment behind veers away from the most direct course the leading boat will also veer in the same sense aiming to stay in between the trailing boat and the next mark. That guarantees still being in the lead no matter how the wind might change direction. Notice that on average this costs time.

Of course in go, not that clearly obvious who is in the lead. That is a skill that needs to be developed, but in some cases even very good players might dispute the situation when not so straightforward (when it is just potential territory)

[Bill Spight]

http://senseis.xmp.net/?YiChangHo

Lee Changho is an interesting example. He rose to the top of the Go world using the style you advocate: Earning small advantages while conceding to the opponent's desires and simplifying, and then playing a precise endgame for the win. Then he switched to a tighter, more fighting style.

Lee Changho may have risen to the top by nailing down won games, but as a young pro he made his bones by fighting.

[Anzu]

Well, I for one disagree that Jesus would always strive to win by one point. I think he would ask for a round number for komi, like 5 or 6 and try to make the game a draw every time.

[topazg]

"No b*** ever won a war by dying for his country. He won it by making some other poor dumb b*** die for his country."

If you have a group you clearly kill in Go without equivalent compensation, you kill it. If you're playing to play the best Go you can, you're also implicitly playing to win. If you're 20 points ahead and he self ataris a group, capture it.

The alternative is to play deliberately bad moves, which IMO can never be considered an attitude with which perfect Go is all that likely