In any problem domain, the definition of "solution" is exactly that, a definition. People can respectfully differ on their definition. In support of your definition, my previous posts have pointed out that recognition of "a winning position" depends on the observer's skill. I generally carry my analyses to a P advantage as the standard for a won position.

As an aside, you might be surprised at how many Sunday puzzles can be "solved" to that standard. (On Sunday, I do most of my computer-assisted analysis after I post.) The only consistent exceptions to complete solution are the monster two-piece sacrifices to make a K walk a tightrope on the third rank with a R cutting off the second rank. It just depends how determined you are and how much time you are willing to spend.

Actually, my claim is doubtful, as I didn't look further than the first two Black moves. However, OTB, I probably would've seen the required combo before saccing the Knight, and I certainly would have after Be5. Take note that the pawns are too far apart to make the Bishop stop one and the King the other, so the sac itself was obvious, and that it won was also obvious.

61....Nxg3
Neat, but Ne3 seems to win easily as well, even in a piece endgame.

62.Bxg3
What else, really? The two pawns pose the same threat, White only has the other option of defending a3.

--a--62.Bg8 Ne4+ with g3
Any other move allows White to win a tempo, either with the same check or by threatening the Bishop.

62....Ka3
As obvious as it is. The square is free now.

63.Be5
Well, yeah, I actually kinda stopped at Ka3. That there is a win is obvious: the pawns are on white squares, so they cannot be threatened. However, if White's King gets too close to the g-pawn, he has the remaining option to sac the bishop into b2 with a draw. So Black should be consistent by using an overworked piece with:

63....g3

64.Kd3

64....g2

65.Bd4

I am afraid I have contributed to a grave psychological problem.

You've <got> to see that g3 is the only winning move after the sac to collect full credit IMO. The first move is very easy (*as someone has pointed out there aren't many possibilities to begin with) ... so accuracy in the line is _required_.

Almost everyone is going to get the first move today, so the puzzle provides a test of character more than anything else.

Here, we have just heard from a guy with a great sense of humor, perhaps a touch obsessive, with just a hint of occasional self-flagellation...

Are you talking to yourself, <dzechiel>? :)>

Well, kinda. After making my original post last night, I saw a number of people proclaim that after 61...Nxg3 that the play would go "62 Bxg3 Ka3 then ...Ka2 and the b-pawn could not be stopped."

I thought this was an over simplification in that the b-pawn can always be stopped (but at the expense of having the g-pawn promote). I set out to compose a message to this effect and demonstrate that the position wasn't as simple as some people thought.

I tried to use my original analysis to show that the b-pawn COULD always be stopped, and during that I noticed that the g-pawn could be stopped as well! This was when I realized that my original post was flawed.

We have already seen that

61 ... Nxg3

and

61 ... Ne3

win. (There are actually two variations to 61 ... Ne3, depending on which pawn promotes.)

The question is whether a third line

61 ... Nh2

also wins. After some analysis, it looks drawn but I can't prove that yet.

Or, <I ♥ endgames...> :-)

Have you seen this endgame puzzle? (I've shown it before, but it's one of my favorites):

click for larger view

Hey, <youRang>! Nobody likes a ❢❣❤❤❥ing smart-❦❧❧!

you cannot move the King (doing so you lose the pawn)

you cannot move either of the two pawns...

It looks to me like 1 Bb1 is the solution. If black charges the pawns, then the white king can prevent black from building a fortress. If black takes the bishop with then 2 Kb3 to trap the black king against the board. Walk the black king over to the g-file (if black pushes his own pawn, then the white king can capture it outright). When ever the black king moves away from the g-file, then white can push his own pawn and capture the black pawn with his king.

So it might go

1 Bb1 Kxb1 2 Kb3 Kc1 3 Kc3 Kd1 4 Kd3 Ke1 5 Ke3 Kf1 6 Kf3 Kg1 7 Kg3

now black must move "away" from the g-file or push the pawn.

7...Kf1 8 g6 Ke2 9 Kf4 10 Kd3 Ke5 11 Ke3 12 Ke6 Ke4 13 Kf7 Kf5 14 Kxg7 1-0

Thank you for your appreciation of my pointing out that the Pawn move ... g3 is necessary to finish matters off. Since many regard your careful analyses as setting the standard for this site, a word of appreciation from you is to be prized.

Hi <Once>,

And yes, after the 2 kings walk together, the key point is when the black king gets to f1, and then white plays g6! and can now get to the black pawn before black has a chance to defend it.

Material: N vs. dark B engame. Black has 2 P's, one passed. Key feature is to look at the color of the B and promotion squares. The b-pawn promotes on light and g-pawn on dark. The b-pawn is on the 6th rank, and is very powerful.

Wish List: The d6 B prevents the Black K from going to a3-a2 where it would protect the b3 pawn promotion. Is there way to deflect the dark-squared B?

Idea: With 61...Nxg3, Black creates a second passed pawn far from the defending K. If White does nothing, Black has won, since the second pawn will march down, be traded for the B and then it will be K+N+P versus K. So White's response is forced.

61...Nxg3 62.Bxg3 Ka3 63.b2

The White K obstructs the B from defending b2. The Black K can go to a2 safely and the dark B cannot prevent promotion on b1.

The antecedent of your second "it" is unclear. I took it to mean that "a computer" managed to lose. Actually is was chessgames.com that did so: