3 edits
Originally posted by XanthosNZPerhaps you should analyse it better. A forced mate it is.
That's not a nitpick. A forced mate is a forced mate, and a forced mate that is not.
1. e4 e5 2. f4 exf4 3. Nf3 g5 4. Bc4 g4 5. O-O gxf3 6. Qxf3
Qf6 7. e5 Qxe5 8. Bxf7+ Kxf7 9. d4 Qxd4+ 10. Be3 Qf6 11. Bxf4 Bg7 12. Nc3 Ne7
13. Nd5 Nxd5 14. Qxd5+
So the starting position from Korchnois book, at the point I realised I was following a lost line.
The main line is-
14. ... Ke8;
(14... Kf8 15. Rae1 Qd4+ 16. Be3+ Qf6 17. Rxf6+ Bxf6 18. Bh6+ Bg7 19. Qf3+ Kg8 20. Re8+ Bf8 21. Rxf8 mate)
(14... Ke7 15. Bg5 d6 16.Rae1+ Kd7 17. Bxf6 Bxf6 18. Rxf6 Kd8 19. Qf7 Nc6 20. Qg7 Be6 21. Rfxe6 a5 22.Qxh8+ Kd7 23. Qxh7+ Ne7 24. Rxe7+ Kc6 25. Rxc7+ Kb5 26. Qd3+ Kb6 27. Qxd6+ Ka7 28. Qd5 Rb8 29. Qxa5 mate)
15. Qh5+ Ke7;
(15... Kd8 16. Bg5 Rf8 (16... Re8 17. Rxf6 Re7 18. Rf7 c6 (18... Bd4+ 19. Kf1 c6 (19... c5 20. Bxe7+ Kc7 21. Qd5 Nc6 22. Bd6+ Kb6 23. c3 Ka6 24. cxd4 b6 25. dxc5 h6 26. cxb6 axb6 27. b4 Bb7 28. b5+ Ka7 29. bxc6 Ba6+ 30. Kf2 Rd8 31. Bc5 Bb5 32. Rxd7+ Ka6 33. Rxd8 bxc5 34. Qxc5 Bxc6 35. Qxc6+ Ka5 36. Ra8+ Kb4 37. Rb1 mate) 20. Bf4 d6 21. Rxe7 Kxe7 22. Re1+ Be6 23. Qxh7+ Kd8 24. Rxe6 Nd7 25. Bxd6 Bf6 26. Rxf6 b5 27. Rf8+ Nxf8 28. Qe7+ Kc8 29. Qc7 mate) 19. Bxe7+ Kc7 20. Rxg7 b6 21. Qe5+ Kb7 22. Rxh7 c5 23. Qe4+ Nc6 24. Rd1 Rb8 25. Bd6 Ra8 26. Bf4 a5 27. Rdxd7+ Ka6 28. a4 Rb8 29. Bxb8 Bxd7 30. Qxc6 Bxc6 31. Ra7 mate)
(16... Nc6 17. Rxf6 Ne7 18. Rf7 Bd4+ 19. Kh1 c6 20. Qh4 Bc5 21.
Bxe7+ Bxe7 22. Qxe7+ Kc7 23. Qe5+ Kb6 {and mate will follow} 24. Qxh8)
(16...d6 17. Rxf6 Bxf6 18. Bxf6+ Kd7 19. Bxh8 {and mate soon follows})
(16... c6 17. Rxf6 Bxf6 18. Bxf6+ Kc7 19. Bxh8 {is equally fatal for black})
(16... c5 17. Rxf6 Bxf6 18. Bxf6+ Kc7 19. Qxc5+ Nc6 {leads to an early mate}))
16. Bg5 Rf8;
17. Bxf6+ Rxf6;
18. Qg5 Bh8;
19. Qe5+ Re6;
20. Qxh8 d5;
21. Qf8+ Kd7;
22. Rf7+ Kc6;
23. Qxc8 Kc5;
24. Qxe6 Nc6;
25. Qe3+ Nd4;
26. b4+ Kb5;
27. a4+ Ka6;
28. Qxd4 c6;
29. Qd3+ b5;
30. axb5+ Kb6;
31. Ra6 mate
In some lines black can delay things by throwing pieces away but the end result is always the same. After move 14 there are a relatively small number of lines for black all ending in mate.
That by my definition, shared by most people, is a forced mate
Originally posted by Dragon FireA forced mate has a depth attached to it. What's the depth in this case (i.e. given best play on what move will mate occur)?
Perhaps you should analyse it better. A forced mate it is.
[b]1. e4 e5 2. f4 exf4 3. Nf3 g5 4. Bc4 g4 5. O-O gxf3 6. Qxf3
Qf6 7. e5 Qxe5 8. Bxf7+ Kxf7 9. d4 Qxd4+ 10. Be3 Qf6 11. Bxf4 Bg7 12. Nc3 Ne7
13. Nd5 Nxd5 14. Qxd5+
So the starting position from Korchnois book, at the point I realised I was following a lost line.
[fen]rnb4r/pppp1k ...[text shortened]... mate.[/b]
That by my definition, shared by most people, is a forced mate[/b]
Originally posted by XanthosNZIn the longest line I have given above the mate seems to be in 16 moves. If you can find a defense for black be my guest but you are missing the whole point of this, which is, that sometimes by blindly following a book (or database) as I did in this game you can just as easily stumble into a lost game as you can a won game and that one should be a bit more circumspect when using both.
A forced mate has a depth attached to it. What's the depth in this case (i.e. given best play on what move will mate occur)?
I think I'll make this my last post on this. I don't wish to debate what is (or is not) a "forced" mate any further as it is irrelevant. A decisive material win is good enough for most people and mate usually follows even if it is not immediately obvious.
Originally posted by Dragon FireI hate to be tedious, but as I've pointed out before in another thread, this line of the Muzio is refuted by 9...Qf5!
Perhaps you should analyse it better. A forced mate it is.
[b]1. e4 e5 2. f4 exf4 3. Nf3 g5 4. Bc4 g4 5. O-O gxf3 6. Qxf3
Qf6 7. e5 Qxe5 8. Bxf7+ Kxf7 9. d4 Qxd4+ 10. Be3 Qf6 11. Bxf4 Bg7 12. Nc3 Ne7
13. Nd5 Nxd5 14. Qxd5+
So the starting position from Korchnois book, at the point I realised I was following a lost line.
[fen]rnb4r/pppp1k ...[text shortened]... mate.[/b]
That by my definition, shared by most people, is a forced mate[/b]
Originally posted by Northern LadI realise that but that line was not given in my book. I posted this just to indicate that blindly following a book can lead you up the wrong alley as it did to me in this game.
I hate to be tedious, but as I've pointed out before in another thread, this line of the Muzio is refuted by 9...Qf5!
Of course I learnt from it and would never follow it to that extent again and now am much more circumspect when following book / database lines always making sure I know where I am heading and it is somewhere I want to go.
Originally posted by Dragon FireDon't get me wrong, I agree entirely with the general point you are making. Korchnoi and Zak's book (apparently 99% Zak) in the seventies was quite a good book at the time, but like virtually all opening books, after 30 years or so it is hopelessly out of date.
I realise that but that line was not given in my book. I posted this just to indicate that blindly following a book can lead you up the wrong alley as it did to me in this game.
Of course I learnt from it and would never follow it to that extent again and now am much more circumspect when following book / database lines always making sure I know where I am heading and it is somewhere I want to go.
The ironic thing about the refutation I mention above is that it was known back in the 19th century (the heyday of the King's Gambit), but for some reason, the clearly unsound Muzio double-piece sac became quite popular in the eighties and nineties, presumably because people had 'forgotten' the established refutation.