Originally posted by vipiuNo kidding that was deep. A home PC would need a week to see that - I'll ask the guys with NASA like computers for playing chess in the playchess engine room how long their machines take.
I think I have just finished my best chess game ever (still, I need to recheck it wit a computer to see if my sacrifices were correct)...anyway, the Q sack is for sure winning:
Game 3967407
On the other hand I'm not surprised because nearly every chess site you go to now has a tactics puzzle and users have a sacing mentality. Even a 1500 can now play a sac (all they need to do is stop players dropping pieces while being sharp tactically).
I've been a 1800-1900 player for long (ICC/FICS/OTB), trust me, I don't think it's a double sacrifice I would ever think up myself.
Actually if this game was played by Fischer, it probably would be mentioned in many chessbooks and even acclaimed as "Game of the Century" . IMHO, this double combination is even harder to find out than that famous "Game of The Century" moves, since the latter had a clear pattern ahead after sacrifice which would at least gaurantee a perpetual check. I think if I am desperate to play some "killer move" in the same position, I probably would find out Fischer's move myself.
But for this double sacrifice we are discussing, I don't think anyone of our level could find it out alone. There's no recognizable tactic pattern follow the Rxg2 sacrifice, and black was not in a position he really needed to sacrifice (In "Game of the Century", Fischer's must find out that move to save his game). I cannot imagine a player below master level would think of and really go ahead the rook sacrifice, only real genius would do.
As far as engine analysis is concerned, first it's extremely hard for a player to find out a winning sacrifice even Fritz would take 10 minutes to even point to it. Yes the human might be better than Fritz strategically, but again, only a master or even a genius can draw the conclusion that for that position a Rxg2 sacrifice is possible even without forseeable tactical compensation.
Second, for correspondances games like played here, it's not strange for an engine user to leave his Fritz running for 10 minutes or more. some might leave engine running while doing other things, only to come back and fine the "killer move". Some might even have the habit to always analyze longer. Some people even input canditate moves themselves and let the engine do the calculation, in which case Fritz might be forced to calculate Rxg2 and took much less time to justify it. Anyway, the fact that even Fritz takes 10 minutes to find a perfect sacrifice does not mean the player thought it up himself at all.
Of course that Rook sacrifice could still be possible to be made by the player all by himself, but it almost certain was a result of "miscalculation went lucky". For the Queen sacrifice that followed, itself still required a master's chess power to calculate, however, I could not exclude the possiblity that the player made that move was just lucky again even if he didn't know what he's really doing then.
Originally posted by Red Night
I would guess, and this is just a guess, that if an engine was involved, that vipiu fed the engine Rxg2 and then saw that it worked rather than the other way around. This is based primarily on the statements from the thread saying that it took Fritz a long time to find the sac on it's own.
I just tried my Fritz 10 on a Core 2 Duo 6400 PC with 1G RAM (not a bad machine but definately not rare at all). If I input Rxg2 myself, Fritz 10 IMMEDIATELY told me that it would at least guarantee black a draw (0.00 score), and in less than 1 minute, Fritz told me that Rxg2 followed by Qb7 would let black win by -2.90.
This just showed us that if black inputted Rxg2 (not a difficult guess) himself, then he would certainly be told by Fritz it's a good move.
Yes, if Rxg2 is not inputted manually, it took much longer for Fritz 10 to find this BEST move. However, other moves would also achieve at least -1.50 for black, which means black was already winning in that position and only a genius or a patzer would think he really need to sacrifice like Rxg2 there.
After 21 Bg3, The Qxf3 sacrifice is the ONLY move for black according to Fritz (Fritz took no time to find it). This is even more interesting since it tells us that black must see Qxf3 sacrifice clearly before he's able to execute the Rxg2 sacrifice! Otherwise Rxg2 just gave away all black's previous advantage.
Also, if white didn't play Bg3 and gave black Qxf3 opportunity, then black's advantage would NOT be that bigger. After 21 Kg1, black would be forced to Qxf3 and then exchange queens... then black is still winning, but only positionally (passed D pawn) with even less major pieces! Even if an 1800 player could calculate that deep, I wonder if he would be confident that his rook sacrifice is justified. Remember, black actually did NOT have to sacrifice a rook, complicate the game in a winning position, while only improve black's score about a pawn's worth!
This is the very reason why I said Rxg2 is much more difficult to find out even than Fischer's "Game of the Century". Fischer's "killer move" is the only move which could save Fischer from trouble, and as long as you started to think about that move, it's very easy to see that you would at least be guarateed a perpetual check in a farmiliar training pattern. So tactically and psychologically, Fischer's famous move is much, much easier to find that Rxg2 followed by Qxf3.
Actually I wonder if a GM would play Rxg2 even if he already saw the Qxf3 refute to 21Bg3. The reason is if white didn't play Bg3, then black must calculate a lot and have a clear understading of whether or not he is enough compensated. Most GMs would rather not take that risk since black is already winning.Only if you use Fritz 10, then it would clearly tell you that Rxg2 is the best move then no matter what follows.
Yeah - I agree with this too. I looked at the game with Fritz 6 (the only engine I own) and it doesn't have any trouble finding this stuff after Rxg2, but it seems to have no clue about Rxg2. This could easily be a computer assisted anlaysis rather than pure computer analysis.
Some engine users might just leave the engine to run continuously for long (due to their habit or just having other things to do then) so Rxg2 could still be found completely by an engine.
Remember, the games playing here are not realtime, they are actually correspondence games, so there's no need to be in a hurry if you use an engine.
The reason why Fritz 10 took more than 10 minutes to find out the Rxg2 move is because the consequence is too complicated, not just tactically (you have to find out the queen sacrifice to refute 21 Bg3), but also strategically (if white choose a different move and the queen is exchanged, then black must be confident it has enough compensate for less major pieces). This fact cannot prove (not a bit) that black is not using an engine, it actually increased the possiblity that black is not using his own mind since that is way beyond his capability.
Lets face it, for all the buzz that this game has generated, it took the opponents "bad" moves to make it happen. So lets not throw too many accolades. For a brilliancy to happen someone has to make a mistake!! The rook sac was speculative, without merit and it happened to work out in the end. Why are the computers not finding this, because of the very fact that it was speculative. Tal may have said there are sacrifices and mine, but this is CC and against a resonably strong player, that sac wouldn't have worked out !! I say toss that game as a one off, it is not a brilliant game it just happened to work to the winners favor !
Originally posted by Fat LadyMaybe vipiu is a CT-Art addict?
Strange how the vast majority of stronger players come to the same conclusion about this game. Must be jealousy I guess.
It does look rather like some of the convoluted Studies with difficulty 90 or more
😉
Originally posted by SquelchbelchHave you ever studied CT-Art?
Maybe vipiu is a CT-Art addict?
It does look rather like some of the convoluted Studies with difficulty 90 or more
😉
I did it thoroughly, so I know only Qf3 sacrifice theme could be in CT-Art. But the Rxg2 sacrifice is definitely beyond CT-Art difficulty or even topic. Rxg2 is more a positional sacrifice than a tactical one, as I found by Fritz
Originally posted by TomBabyYes. Mostly the first 500-600 (up to level 40) but a few of the higher problems.
Have you ever studied CT-Art?
As a 1550-1650 player, virtually all of the CT-Art puzzles on 40 upwards are a severe case of hit & hope especially if I try to solve them with any speed.
I could see vipiu's being there in the 90+ section.
Originally posted by SquelchbelchI use CT-Art 3.0 and my rating there is 2100+, I would solve many 2400 puzzles, though normally with some incomplete/incorrect calculations.
Yes. Mostly the first 500-600 (up to level 40) but a few of the higher problems.
As a 1550-1650 player, virtually all of the CT-Art puzzles on 40 upwards are a severe case of hit & hope especially if I try to solve them with any speed.
I could see vipiu's being there in the 90+ section.
Yes, sometimes I could "sense" the solution even before I could calculate all the variations. This is common when you KNOW you MUST solve a tactical puzzle. However, in real games you definitely will not and cannot play like solving puzzles since most of the time the position is not "ripe" to be a puzzle yet and if you force a sacrifice, you would probably be refuted without second solving chance. If you always know it's high time you started solving CT-Art like tactical puzzles, then you must be extremely strong positionally and tactically.
In this actual game we are talking about, black is already positionally winning and had initiative, so he didn't need to find a "killer move" desperately. If that position is a CT-Art puzzle, yes, even I would probably choose Rxg2 as my first choice. But it is NOT so if you said black would try that Rxg2 move like solving a CT-Art puzzle, then black must be a positional genius or just a careless but lucky patzer.
Actually that position itself is not even appropriate for CT-Art puzzles: although in one variation black could sacrifice the queen and win, it did NOT have forced winning line which would greatly increase black's winning chance (it only increased Fritz 10 score of a pawn) in other variations and the final position is still enough complicated.
I myself would also think about that Rxg2 move since I also have a CT-Art intuition🙂, but I would give it up very soon since it's not solid unless I could see that queen sacrifice (after a wait queen move!). So unless I don't care about my game and just wanted to try sacrifice for fun, I will never have the enough reason to play Rxg2 myself. I think only a GM could find that enough reason to play Rxg2, though I could not exclude the possiblity that in this world some weird people just tried some crazy,unimaginable thing and get lucky, like point a place unreasonably and really dig out a rare treasure.🙂
Please note I never said anybody is cheating, I just pointed out (through chess reasoning) that he must be either a real genius or just a lucky patzer if he is not using engine. What I will NOT believe is he is just a normal 1800 player like me. No, I will NEVER be able to find that sacrifice even if I solved many difficult tactical puzzles in CT-Art.