Author: Vincent Diepeveen
Date: 07:08:23 06/01/04
Go up one level in this thread
On May 31, 2004 at 08:54:13, Uri Blass wrote:
>On May 31, 2004 at 08:37:47, Mike Byrne wrote:
>
>>On May 31, 2004 at 07:20:39, Uri Blass wrote:
>>
>>>On May 30, 2004 at 23:48:26, Mike Byrne wrote:
>>>
>>>>This is semi-follow up to Jorge post regardng Game 6 of the first match between
>>>>Kasparov and Deep Blue , but not directly so I started a new thread.
>>>>
>>>>I witness this game live in Philadelphia with my brother-in-law. If anybody is
>>>>interested in a program from the match . e-mail me privately. There was
>>>>laughter after Nh5, it certainly did look like a computer move at the time..
>>>>
>>>>Annotations Copyright by Chessbase
>>>>
>>>>[Event "Philadelphia m"]
>>>>[Site "Philadelphia"]
>>>>[Date "1996.02.17"]
>>>>[Round "6"]
>>>>[White "Kasparov, Garry"]
>>>>[Black "Comp Deep Blue"]
>>>>[Result "1-0"]
>>>>[ECO "D30"]
>>>>[WhiteElo "2795"]
>>>>[Annotator "Friedel"]
>>>>[PlyCount "85"]
>>>>[EventDate "1996.02.??"]
>>>>[Source "ChessBase"]
>>>>
>>>>1. Nf3 {Keene Borik} d5 2. d4 c6 3. c4 e6 4. Nbd2 Nf6 5. e3 c5 {a tempo-losing
>>>>move to deviate from game four. The Deep Blue team has prepared a line that
>>>>should open up the position.} 6. b3 Nc6 7. Bb2 cxd4 8. exd4 Be7 9. Rc1 O-O 10.
>>>>Bd3 Bd7 11. O-O Nh5 $2 {
>>>>A very strange move which absolutely nobody at the site liked.} 12. Re1 Nf4 13.
>>>>Bb1 Bd6 14. g3 Ng6 15. Ne5 Rc8 16. Nxd7 Qxd7 17. Nf3 Bb4 18. Re3 Rfd8 19. h4
>>>>Nge7 20. a3 Ba5 21. b4 Bc7 22. c5 {Four consecutive pawn advances which drive
>>>>back all the black pieces, which are stumbling over each other on the
>>>>queenside.} Re8 23. Qd3 g6 24. Re2 Nf5 25. Bc3 h5 26. b5 {Keene calls this
>>>>"Kasparov's strategy of strangulation" and points out that 26.b5 doesn't just
>>>>attack the knight but establishes "a giant, crawling mass of white pawns,
>>>>rather resembling a colossal army of soldier ants on the move."} Nce7 27. Bd2
>>>>Kg7 28. a4 Ra8 29. a5 a6 30. b6 Bb8 {# Kasparov has shut the black bishop and
>>>>rook out of play to the end of the game. Black's position is lost.} 31. Bc2 Nc6
>>>>32. Ba4 Re7 33. Bc3 Ne5 {actually accelerating the end.} 34. dxe5 Qxa4 35. Nd4
>>>>Nxd4 36. Qxd4 Qd7 {IM Otto Borik that other variations also lose:} (36... Qxd4
>>>>37. Bxd4 {and Rb2, c6 wins, e.g.} Re8 38. Rb2 Rc8 39. c6 Rxc6 40. Rxc6 bxc6 41.
>>>>b7 Ra7 42. Bxa7 Bxa7 43. b8=Q Bxb8 44. Rxb8) (36... Qc6 37. Bd2 Rd7 38. Bg5 Kf8
>>>>39. Bf6 {and now f3, Rg2 and g4 wins.}) 37. Bd2 Re8 38. Bg5 Rc8 39. Bf6+ Kh7
>>>>40. c6 $1 bxc6 (40... Rxc6 41. Rec2 Rxc2 42. Rxc2 Qe8 43. Qc5 {wins}) 41. Qc5
>>>>Kh6 42. Rb2 Qb7 43. Rb4 $1 {And the Deep Blue team reseigned for the machine.
>>>>Why did Black resign? IM Malcolm Pein explained this on the Internet: "Black
>>>>has four pieces left plus his king. The rook on a8 and the bishop on b8 cannot
>>>>move. If the queen on b7 moves it allows b7, winning a rook. If the rook on
>>>>c8 moves White can play Qxc6, forcing an exchange of queens. After that there
>>>>are many ways to win, the most prosaic being double on the c file and play Rc8.
>>>>So we are left with Kh7! The simplest way then is Qe7 Qxe7 Bxe7 threatening b7
>>>>and if Rc8-e8 then b7 Ra7 Bc5 etc. Note that had Kasparov left his rook on b2
>>>>Black would have ...Bxe5 gaining a tempo."} (43. Rb4 Qd7 (43... Re8 44. Qxc6
>>>>Qxc6 45. Rxc6 Kh7 46. b7 Ra7 47. Rbb6 Rg8 48. Rc8 d4 49. Rbc6 g5 (49... d3 50.
>>>>Rxg8 Kxg8 51. Rc8+ Kh7 52. Rh8#) 50. Rxg8 Kxg8 51. Rc8+ Kh7 52. Rh8+ Kg6 53.
>>>>Rg8+ Kf5 54. f3 {Threat: Rxg5#} Bxe5 55. Bxe5 {Threat: ditto} Kxe5 56. b8=Q+ {
>>>>and mate.}) (43... Kh7 44. Qe7 Qxe7 45. Bxe7 Re8 46. b7 Ra7 47. Bc5 Rd8 48.
>>>>Bxa7 Bxa7 49. Rxc6 Bb8 50. Rc8 {winning}) 44. b7) 1-0
>>>>
>>>>[d]2rr2k1/pp1qnppp/2n1p3/3p4/1bPP3P/1P2RNP1/PB3P2/1BRQ2K1 w - - 0 20
>>>>
>>>>There was much disussion in the audience about 20.Bxh7! - Yasser indicating
>>>>that against a human , Kasparov most definitely would have played that move.
>>>>After the game, Kasparov indicated as such - but he did not play it because he
>>>>saw no reason to take the chance against Deep Blue. He was confident that he
>>>>had a "won" game at this point and the was no reason to take unnecceary risks.
>>>>Hsu also confirmed later that Deep Blue also like Bxh7 as the best move and it
>>>>saw white with a winning score.
>>>
>>>
>>>I remember that I read that it saw only a draw score for that move.
>>>I never read that it saw winning score for Bxh7.
>>>
>>>Where did you read about the claim that deep blue saw Bxh7 with a winning score.
>>>
>>>Uri
>>
>>I do not remember reading it and I did not claim I read it in my post above. I
>>was there and I heard it spoken the same day. Dr Hsu spoke after Kasparov. As
>>I remember, Dr Hsu said Deep Blue thought Bxh7 was the best move with a "plus
>>score" or "winning score" - I cannot remember exactly which words he used - but
>>the advantage was with white. Perhaps later analysis showed that it was nothing
>>more than a draw - I do not know. I do remember the position, and Shredder 8,
>>the strongest program available for the PC today finds the move within a
>>reasonable time on my machine with a plus score for white.
>>
>>6 years later , on ICC , Saturday, October 19, 2002, after game 8 of Kramnik vs
>>Deep Fritz, there was a short discussion with Dr Hsu about that position.
>>
>>His recollection is a tad more fuzzy than my recollection but he did not rule
>>that Bxh7 was perhaps favored by Deep Blue. But as Kasparov indicated, Kasparov
>>saw that a3 and the his pawn push was going to immobilise balck's pieces and he
>>had a "won" at that point - so why take the chance with Bxh7 that decidedly less
>>clear.
>>
>>==================================================================
>>
>>Moderator is SJLIM.
>>Feng-Hsiung Hsu is CrazyBird.
>>
>>
>>SJLIM(* DM) kibitzes: I think we have only one more tech question for
>>now..
>>SJLIM(* DM) kibitzes: I have a question - it's about Game 6 in the
>>1996 match. Did DB think that 20 Bxh7+ was a draw? And if so, what
>>does CB think about Berliner's analysis showing that this move would
>>win?
>>CrazyBird(DM) kibitzes: game 6? Kasparov was winning all the time. are
>>u sure that was the game?
>
>I think that there is no contradiction between saying that kasparov was winning
>all the time and saying that DB expected 20.Bxh7+ with a draw score.
>
>The question was simply if DB evaluated Bxh7+ as a draw and not about the
>objective evaluation of the position.
>
>It is a pity that Hsu did not answer the question and escaped by doubting if it
>is the relevant game.
>
>Uri
Bob is right here. Deep Blue did evaluate it as a draw and it is logical why.
It was getting like 10 or 11 ply or so i guess and the tactics to see Bxh7
winning is way way deeper.
It involves another trick. After bxh7 you get a position where white can win by
pinning another piece. However to see that in search is not so easy as you can
of course nullmove after h4.
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