Lyudmil Tsvetkov wrote:beram wrote:Lyudmil Tsvetkov wrote:beram wrote:Lyudmil Tsvetkov wrote:pilgrimdan wrote:Lyudmil Tsvetkov wrote:I will post this here, as it has some relevance to computer chess and human-engine competition.
After doing an extensive study of the Fischer game collection, with the help of Stockfish, I just published a book on the theme:
While going through the positional test suite, including 112 test positions, I had to ascertain that Stockfish still fails to solve around one third, but maybe even close to half of the puzzles. With the tactical set, Stockfish has no problems at all, all solved.
Make the conclusions yourselves how weak actually Stockfish is and how strong Fischer.
So, you might just want to forget anything about alleged engine superiority in chess.
sounds interesting Lyudmil ... may buy and take a look ...
[d]r4rk1/2q1bpp1/pn3n1p/1pp1pP2/6P1/1BP4P/PP1N1P2/R1BQR1K1 w - - 0 17
One of the positions from the positional suite my SF does not see(I don't know about the latest version on big hardware).
17. h4 wins
Does any engine see this easily wins?
Why would SF fail to see that?
It's not you Dan, I guess SF developers need the book.

The move h4! doesn't win Lyudmil
You bet!
Any analysis?
I will give you this testposition after 17 h4
Which black move equalizes here?
A Nfd5
B c4
C Nh7
D Ne8
E Nfd7
I will give you the analysis if you choose the right one
[d] r4rk1/2q1bpp1/pn3n1p/1pp1pP2/6PP/1BP5/PP1N1P2/R1BQR1K1 b - - 0 17
None.
Just give me your best line of play(you are probably using the alternative Houdini), and I will tell you why that su*ks.
White is winning that, not the slightest doubt about it.
The only drawing move here is answer D 17..Ne8!
Black threatens to win h4 and 18 g5 doesn't work here
The best way white can try now is to play 18 Ne4 leaving black h4 but after 18 ..Bxh4 19 Qf3 black plays Nf6 (or even Nd6) to fully equalize after 20 Qh1 Nxe4 21 Qh4 c4!
The ‘big three’ all give 0.00 than at enough depth
Another white line leading to same position is 18 Qf3 because after again 18..Bxh4 whites best move is Ne4 and than black plays Nf6 leading to same variation
The only other plausible move which white has here than is 18 Nf3
But after e4! 19 Nd2 Bxh4 20 Nxe4 Nf6 21 Qf3 Rfe8 22 Qh1 Nxe4 23 Qxh4 this leads to a position where white has nothing special and again here the ‘big three’ all gave 0.00 after not that long time and depth
Latest Stockfish 171226 has Ne8 as best line at mv 5 at dept 43 this after about 1 hour thinking time on my AMD Ryzen 1800 with 14threads
1: Fisher - Benko
[d] r4rk1/2q1bpp1/pn3n1p/1pp1pP2/6PP/1BP5/PP1N1P2/R1BQR1K1 b - - 0 1
Analysis by Brainfish 261217 64 POPCNT at depth 43 after about 1h 30m on AMD Ryzen 1800 14t 8Gb Hash:
1. = (0.08): 17...Pf6-e8 18.Dd1-f3 Le7xh4 19.Pd2-e4 Pe8-d6 20.Df3-h3 Pd6xe4 21.Dh3xh4 c5-c4 22.Te1xe4 c4xb3 23.f5-f6 Dc7-c6 24.g4-g5 Pb6-d7 25.g5xh6 g7-g6 26.h6-h7+ Kg8-h8 27.a2xb3 Pd7xf6 28.Te4xe5 Ta8-e8 29.Lc1-g5 Pf6-h5 30.Lg5-e7 f7-f6 31.Te5-e3 Tf8-f7 32.Ta1-e1 Kh8xh7 33.Dh4-g4 a6-a5 34.Le7-c5 Te8xe3 35.Lc5xe3 Tf7-d7 36.Le3-d4 Kh7-g7 37.Dg4-e6 Dc6xe6 38.Te1xe6 Ph5-f4 39.Ld4xf6+ Kg7-f7 40.Te6-a6 Td7-d2 41.c3-c4 b5xc4 42.b3xc4 Pf4-d3 43.Lf6-c3 Td2xf2 44.Ta6-a7+ Kf7-e6 45.Ta7xa5 Tf2-c2 46.Ta5-a6+ Ke6-f7 47.Ta6-d6 Pd3xb2 48.Lc3xb2 Tc2xb2 49.c4-c5 Kf7-e7
2. +/= (0.54): 17...Pf6-h7 18.g4-g5 h6xg5 19.Pd2-e4 c5-c4 20.Lb3-c2 g5xh4 21.Dd1-g4 Ph7-f6 22.Dg4xh4 Pf6xe4 23.Dh4xe4 Le7-f6 24.Te1-e3 Tf8-d8 25.Te3-h3 Ta8-c8 26.b2-b3 Dc7-d6 27.De4-f3 e5-e4 28.Df3-g4 Pb6-d5 29.Lc1-d2 Pd5-b4 30.Ld2-f4 Dd6-c6 31.Dg4-h5 Kg8-f8 32.Lc2xe4 Dc6xe4 33.Th3-e3 De4xe3 34.f2xe3 Pb4-d3 35.b3xc4 Tc8xc4 36.Ta1-d1 Tc4xc3 37.Lf4-g5 Kf8-e7 38.Lg5xf6+ g7xf6 39.Dh5-f3 Pd3-e5 40.Df3-b7+ Td8-d7 41.Td1xd7+ Pe5xd7 42.Db7xa6 Tc3xe3 43.Da6xb5 Te3-e5 44.Db5-d3 Pd7-c5 45.Dd3-b1 Ke7-f8 46.Kg1-g2 Kf8-e7 47.Db1-b4 Te5xf5
3. +/= (0.60): 17...Pf6-d5 18.g4-g5 h6xg5 19.Pd2-e4 c5-c4 20.Lb3-c2 g5xh4 21.Dd1-g4 Pd5-f6 22.Dg4xh4 Pf6xe4 23.Dh4xe4 Le7-f6 24.Te1-e3 Tf8-d8 25.Te3-h3 Ta8-c8 26.b2-b3 Dc7-d6 27.De4-h1 Dd6-d1+ 28.Lc2xd1 Td8xd1+ 29.Kg1-g2 Td1xh1 30.Th3xh1 Pb6-d5 31.Lc1-d2 e5-e4 32.Ta1-c1 b5-b4 33.b3xc4 Pd5xc3 34.Th1-h3 g7-g6 35.f5xg6 f7xg6 36.a2-a3 a6-a5 37.a3xb4 a5xb4 38.Tc1-a1 Tc8-d8 39.Ta1-a6 Td8xd2 40.Ta6xf6 Kg8-g7 41.Tf6-b6 Pc3-d1 42.Kg2-f1 Pd1xf2 43.Th3-g3 Pf2-d3 44.Tg3xg6+ Kg7-h7 45.Tg6-f6 Td2-c2 46.Tb6-b7+ Kh7-g8 47.Tf6-g6+ Kg8-f8
4. +/- (0.79): 17...Pf6-d7 18.g4-g5 h6xg5 19.Pd2-e4 g5xh4 20.Kg1-h2 Pd7-f6 21.Te1-g1 Tf8-d8 22.Dd1-f3 Pf6xe4 23.Df3xe4 Le7-f6 24.Lc1-h6 Kg8-f8 25.De4-g4 c5-c4 26.Lh6xg7+ Lf6xg7 27.Dg4xg7+ Kf8-e7 28.Dg7-g5+ Ke7-d7 29.Lb3-c2 Kd7-c8 30.Ta1-d1 Ta8-b8 31.Td1xd8+ Dc7xd8 32.Dg5-h6 Kc8-b7 33.Tg1-g7 Dd8-c7 34.Dh6xh4 Kb7-a7 35.Dh4-f6 Tb8-b7 36.Lc2-e4 Dc7-e7 37.Df6xe7 Tb7xe7 38.f5-f6 Te7-c7 39.Le4-f3 Pb6-c8 40.Tg7-g5 e5-e4 41.Lf3xe4 Pc8-d6 42.Le4-g2 Pd6-e8 43.Tg5-f5 Tc7-d7 44.Lg2-c6 Td7-d8 45.Kh2-g3 Ka7-b6 46.Lc6xe8 Td8xe8
5. +/- (0.82): 17...c5-c4 18.Lb3-c2 Pf6-d5 19.g4-g5 h6xg5 20.Pd2-e4 g5xh4 21.Dd1-g4 Pd5-f6 22.Dg4xh4 Pf6xe4 23.Dh4xe4 Le7-f6 24.Te1-e3 Tf8-d8 25.Te3-h3 Ta8-c8 26.b2-b3 Dc7-d6 27.De4-f3 e5-e4 28.Df3-h5 Kg8-f8 29.Dh5-e2 Kf8-g8 30.De2-g4 Pb6-d5 31.Lc1-d2 Pd5-b4 32.Ld2-f4 Dd6-d5 33.b3xc4 Tc8xc4 34.Ta1-d1 Pb4-d3 35.Lc2-b3 Pd3xf4 36.Td1xd5 Pf4xh3+ 37.Dg4xh3 Td8xd5 38.Lb3xc4 b5xc4 39.Dh3-e3 Td5xf5 40.De3xe4 g7-g6 41.De4xc4 Kg8-g7 42.Kg1-g2 Tf5-g5+ 43.Kg2-f1 Tg5-h5 44.Dc4xa6 Lf6xc3
78: Fisher - Benko, 1965
Analysis line after 17...Pf6-e8 18.Dd1-f3 Le7xh4 19.Pd2-e4 Pe8-d6 20.Df3-h3 Pd6xe4 21.Dh3xh4 c5-c4
[d] r4rk1/2q2pp1/pn5p/1p2pP2/2p1n1PQ/1BP5/PP3P2/R1B1R1K1 w - - 0 1
Analysis by Brainfish 261217 64 POPCNT:
22.Te1xe4
= (0.26 ++) Diepte: 34/44 00:00:14 245MN
22.Te1xe4 c4xb3 23.f5-f6 Dc7-c6 24.g4-g5 h6-h5 25.a2xb3 Tf8-e8 26.f6xg7 Dc6-g6 27.Te4-e3 Ta8-d8 28.Te3-h3 Td8-d1+ 29.Kg1-g2 Pb6-d5 30.Ta1xa6 Dg6-b1 31.Dh4xh5 Pd5-f4+ 32.Lc1xf4 Td1-g1+ 33.Kg2-h2 Tg1-h1+ 34.Kh2-g3 e5xf4+ 35.Kg3-h4 Th1xh3+ 36.Kh4xh3 Db1-h1+ 37.Kh3-g4 Dh1-g2+ 38.Kg4xf4 Dg2xf2+ 39.Dh5-f3 Df2-h2+ 40.Kf4-g4 Dh2-g1+ 41.Kg4-h4 Dg1-h2+ 42.Kh4-g4
= (0.00) Diepte: 34/48 00:00:18 308MN
22.Te1xe4 c4xb3 23.f5-f6 Dc7-c6 24.g4-g5 h6-h5 25.a2xb3 Tf8-e8 26.f6xg7 Dc6-g6 27.Te4-e3 Ta8-d8 28.Te3-h3 Td8-d1+ 29.Kg1-g2 Pb6-d5 30.Ta1xa6 Dg6-b1 31.Dh4xh5 Pd5-f4+ 32.Lc1xf4 Td1-g1+ 33.Kg2-h2 Tg1-h1+ 34.Kh2-g3 e5xf4+ 35.Kg3-h4 Th1xh3+ 36.Kh4xh3 Db1-h1+ 37.Kh3-g4 Dh1-g2+ 38.Kg4xf4 Dg2xf2+ 39.Dh5-f3 Df2-h2+ 40.Kf4-g4 Dh2-g1+ 41.Kg4-h4 Dg1-h2+ 42.Kh4-g4
= (0.00) Diepte: 35/42 00:00:26 436MN
22.Te1xe4 c4xb3 23.f5-f6 Dc7-c6 24.g4-g5 h6-h5 25.a2xb3 Tf8-e8 26.f6xg7 Dc6-g6 27.Te4-e3 Ta8-d8 28.Te3-h3 Td8-d1+ 29.Kg1-g2 Pb6-d5 30.Ta1xa6 Dg6-b1 31.Dh4xh5 Pd5-f4+ 32.Lc1xf4 Td1-g1+ 33.Kg2-h2 Tg1-h1+ 34.Kh2-g3 e5xf4+ 35.Kg3-h4 Th1xh3+ 36.Kh4xh3 Db1-h1+ 37.Kh3-g4 Dh1-g2+ 38.Kg4-h4 Dg2xf2+ 39.Kh4-g4 Df2-g1+ 40.Kg4-f5 Dg1-c5+ 41.Kf5-g4 Dc5-g1+
= (0.00) Diepte: 36/41 00:00:32 544MN (Bram, 02.01.2018)