title: Battling the London System

text:
# Question
Title: Battling the London System
I seem to have fairly good success against the London system and the Colle using the Queen's Indian defense. Has there been any games at the Senior master level where the Queen's Indian has been used?

# Answer
If you click yourself through the opening moves at http://chessok.com/?page\_id=352 you'll find that after 1. d4 Nf6 2. Bf4 e6 3. Nf3 b6 there are still 1907 games, the highest white rating is 2724 and the highest black rating is 2815.

So the queen's indian setup against the London is completely respectable and was even played by Kasparov (in some kind of internet blitz games, but still …).

This is not particularly surprising, after all it is a very solid setup vs a very solid setup. Nobody is trying to refute anybody's opening play, hard to imagine anybody would be much better/worse already.
> 0 votes

# Answer
I set out to answer my own question with the help of two computers. A Dell desk top using Windows 7 and a Dell laptop using Windows XP. The desktop used Deep Fritz 12 and Fritz 11 was used on the laptop. I played the London opening against Deep Fritz 12 and it appeared to use the Semi-Tarrasch. After I set-up the opening in Fritz 11, Deep Fritz 12 lost to Fritz 11. I wanted to try the Queens Indian. The second time I played the London system against Deep Fritz 12 Deep Fritz wanted to play the Grunfeld. I had to force it to play the Queens Indian. After 51 moves Fritz 11 resigned.

```
[Event "Blitz 45m"]
[Site "Independence"]
[Date "????.??.??"]
[Round "?"]
[White "Gyr_man/Fritz 11"]
[Black "Deep Fritz 12"]
[Result "*"]
[PlyCount "80"]
[TimeControl "2700"]
[fen ""]

1. d4 {0} Nf6 {0} 2. Nf3 {0} e6 {0} 3. Bf4
{0} b6 {0} 4. e3 {0} Be7 {0} 5. h3 {16} Bb7 {3} 6. Be2 {166} d5 {217} 7. Nc3 {
154} O-O {0} 8. O-O {134} c5 {0} 9. Ne5 {186} Nc6 {0} 10. Bb5 {151} Rc8 {0} 11.
a3 {70} cxd4 {83} 12. Bxc6 {90} Bxc6 {0} 13. Nxc6 {167} Rxc6 {0} 14. exd4 {97}
Bd6 {21} 15. Qd2 {61} Bxf4 {171} 16. Qxf4 {14} Qc7 {275} 17. Qg5 {155} Ne8 {123
} 18. Rfd1 {63} Nd6 {179} 19. Qg3 {6} Rc8 {60} 20. Ra2 {66} b5 {87} 21. Qf4 {52
} a5 {131} 22. Raa1 {10} Qd8 {122} 23. Rab1 {70} h6 {39} 24. Ra1 {70} Rc4 {177}
25. g3 {12} g5 {26} 26. Qf3 {63} Kg7 {0} 27. Kg2 {39} b4 {1} 28. axb4 {63} axb4
{0} 29. Na2 {53} Rxc2 {18} 30. Nxb4 {39} Rxb2 {0} 31. Nd3 {105} Rbc2 {0} 32.
Nc5 {100} Nf5 {45} 33. Qd3 {33} Rc4 {0} 34. Rdc1 {20} Ra8 {11} 35. Rxa8 {23}
Qxa8 {0} 36. Nb3 {34} Qa4 {34} 37. Ra1 {22} Qb4 {57} 38. Ra7 {11} Qb6 {40} 39.
Ra2 {20} Qc7 {5} 40. Qd2 {0} Nxg3 {29} (40... Nxg3 {7} 41. fxg3 {41} Rc3 {0}
42. Qf2 {59} Rxb3 {0} 43. Rd2 {22} h5 {38} 44. Rb2 {39} Rxb2 {2} 45. Qxb2 {19}
h4 {17} 46. gxh4 {8} gxh4 {27} 47. Qf2 {11} Qg3+ {7} 48. Qxg3+ {33} hxg3 {0}
49. Kxg3 {14} Kg6 {1} 50. Kf3 {26} Kg5 {4} 51. Kg3 {27} Kh5 {4}) *

```
> 1 votes

# Answer
Here is another example of how to win against the London, using the Queen's Indian defense. I played the following game on line a couple of weeks ago. His rating was 1342 but I think he was better than that. I saw no blunders on his part. I will be using Deep Fritz 12 in full analysis mode, 30 seconds/move. This was a Game 30. Deep Fritz 12 did call my 22nd move a blunder, and I agree, but in my defense I was simply buying time. I wanted to stay a few minutes ahead of him on time and then begin my attack when he had less than five minutes to play.

\[Event "?"\] \[Site "?"\] \[Date "????.??.??"\] \[Round "?"\] \[White "New game"\] \[Black "?"\] \[Result "0-1"\] \[Annotator "Deep Fritz 12 (30s)"\] \[PlyCount "74"\]

{A46: 1 d4 Nf6 2 Nf3 e6: Torre, London and Colle Systems} 1. Nf3 Nf6 2. Nc3 e6 3. d4 {last book move} b6 (3... d5 4. g3 $11) 4. h3 {Covers g4} (4. e4 $5 $16) 4... Bb7 $11 5. a3 {Controls b4} Be7 6. Bf4 d5 7. e3 O-O 8. Bd3 c5 9. dxc5 (9. O-O Ne4 $11) 9... Bxc5 (9... bxc5 10. O-O $11) 10. b4 Bd6 11. Bxd6 (11. Nb5 Bxf4 12. exf4 Nc6 $11) 11... Qxd6 $15 12. Nb5 Qd7 (12... Qe7 13. Ne5 $15) 13. Ne5 {White threatens to win material: Ne5xd7} Qe7 14. O-O Nc6 15. Nxc6 Bxc6 16. Nc3 (16. c4 dxc4 17. Bxc4 Rfd8 $11) 16... Rac8 17. Rc1 Rfd8 18. Bb5 $4 { further deteriorates the position} (18. Qe1 e5 $17) 18... Bb7 (18... Ne4 $142 { and Black has prevailed} 19. Nxe4 Bxb5 $19 (19... dxe4 $6 20. Qe2 $15)) 19. Ne2 $17 a6 20. Bd3 b5 (20... e5 21. c3 $17) 21. f3 {Prevents intrusion on e4+g4} ( 21. c3 e5 $15) 21... Qc7 (21... e5 22. Bf5 Rc7 23. h4 $19) 22. c3 (22. f4 $5 $15) 22... Qb6 $17 23. Qd2 (23. Nd4 $17) 23... Qd6 $4 {releasing the pressure on the opponent} (23... Ne4 $142 {a shame that Black overlooked this excellent chance} 24. fxe4 dxe4 $19) 24. Qe1 Qb6 {Black threatens to win material: Qb6xe3 } 25. Qf2 (25. Qd2 Ne4 26. fxe4 dxe4 $19) 25... Qc6 (25... Rc7 26. Bc2 $15) 26. Rfd1 (26. Nd4 Qd6 $11) 26... Rd7 27. Nd4 {White threatens to win material: Nd4xc6} Qb6 28. Re1 Rdc7 29. Qd2 e5 {Black threatens to win material: e5xd4} 30. Ne2 (30. Nb3 $5 $15) 30... e4 31. fxe4 dxe4 32. Bb1 Rd7 33. Qc2 $4 {solves nothing} (33. Nd4 $142 $17) 33... Qxe3+ $19 34. Kh1 Qg5 (34... Rd2 $142 {makes it even easier for Black} 35. Nd4 Rxc2 36. Bxc2 $19 (36. Rxe3 $4 {White will choke on his greed} Rxc1+ 37. Kh2 Rxb1 $19)) 35. g3 (35. Rcd1 {otherwise it's curtains at once} Rd3 $1 {a fitting end to a beautiful game} 36. Ng1 $19) 35... e3+ 36. Kg1 Qd5 37. Nf4 (37. Qe4 {cannot change what is in store for ?} Nxe4 38. Nf4 Qd2 39. Rf1 e2 40. Nd5 exf1=Q+ 41. Rxf1 Bxd5 42. Rf3 Qe1+ 43. Kg2 Ng5 44. Bxh7+ Kxh7 45. h4 Bxf3+ 46. Kh2 Rd2#) 37... Qh1# 0-1
> 0 votes

---
Tags: opening, colle-system, queens-indian, london-system
---


title: Eligibity prediction

text:
# Question
Title: Eligibity prediction
I am from Pondicherry and I want to become a world class player. I have the following background:

* Tech (electrical & electronics eng) graduate.
* Have won in chess with friends but have not contested in any tournaments.
* Good at maths

Do I need to go for coaching? What is the progression of a chess player from beginner to world champion? How long does it take? Where can I find more information about tournaments and how to enter them?

# Answer
The current world champion Magnus Carlsen needed around 15 years to go from beginner to world champion. He was probably one of the fastest ever because he started to play quite late (at the age of eight) and was the second youngest classical world champion (if I remember correctly).

He received professional training from a strong GM almost from the beginning. He played tournaments almost constantly. His parents took a year off work, to accompany him to tournaments. Due to his tight tournament schedule he didn't finish school, although it was a special sports school, where he received more chess training.

So, if you are 8 years old or younger, and you can afford to concentrate on chess for the next 10 years, you do have a shot at being world class some day.

Otherwise, not so much …

Anyway, I would advise you to go to a local chess club. Google tells me that there are chess clubs in Pondicherry. There you will find out, whether playing tournament chess is actually enjoyable for you. I believe that was a necessary step for every chess world champion.
> 2 votes

---
Tags: tournament
---


# Question
Title: Elo rating of the best player from the 19th century, if he played today?
Take the best player from the 19th century, at his prime, and imagine he started playing tournaments today. He can't learn new stuff. What Elo would he achieve?

# Answer
Ken Regan's research (e.g., Understanding Distributions of Chess Performances \- PDF link) suggests that the best players of the 19th century were playing at a level in the 2400-2500 range (see the table on page 9 of that paper).
> 5 votes

---
Tags: history, rating, elo
---


title: Is it possible to play vs bots on FICS?

text:
# Question
Title: Is it possible to play vs bots on FICS?
I was playing a 15 min game vs some 2300 guy. He doesn't take any time to think about his next move, not even a second, not even against a c4 opening. When i offered him to play, he accepted immediately, instantly.

He blunders or should I say, he plays slow moves, but he's strong, so no obvious blunders.

Is it possible that bots play on FICS servers? Like you run a bot client, connect it to the server and that's it? since there's no CAPTCHA or anything to make sure that you're a human? And since you can connect to FICS in so many ways?

# Answer
To answer your question: There are computer accounts in FICS, with handles ending in (C). Also guests may be computers. There might be computers also behind other players, but that's against the rules of FICS. Engines can be connected to FICS using icsDrone, XBoard/WinBoard with Zippy, or similar tools.
> 4 votes

# Answer
There are some computer accounts that are on the site, so if you see one ending in (C), abort the game or resign. Another website is chess.com, which is really good.
> -1 votes

---
Tags: online-chess, cheating
---


# Question
Title: Where can I find a list of mutual zugzwangs from Queen vs Rook?
Is there a list of mzugs from KQKR?

# Answer
In this particular endgame, there are no mutual-zugzwang-positions.

An overview over the positions is at

http://chess.jaet.org/cgi-bin/mzugs
> 2 votes

---
Tags: rook-endgame, queen-endgame, zugzwang
---


title: Frequency of resigning in won positions

text:
# Question
Title: Frequency of resigning in won positions
The most terrible blunder is to resign in a won position.

How can I systematically search for such games ?

How often does this happen if both opponents have, lets say, at least ELO 2400 ?

# Answer
> 7 votes
There is a comprehensive list on Tim Krabbé's page The Ultimate Blunder.

---
Tags: blunder, resigning
---


title: "Dead-draw" endgame lost?

text:
# Question
Title: "Dead-draw" endgame lost?
Are there examples of games between notable players where "dead-draw" endgames were lost ?

For examples : Both players had three connected pawns on the f-g-h-file (or a-b-c file) without free pawns and the king were near the pawns and material was level.

Such positions are generally considered to be "dead-draw".

# Answer
This game between Ponomariov and Carlsen was quite a sensation in 2010. Especially because there is no single outrageous blunder - Ponomariov is just outplayed very systematically. Alas, one has to keep in mind that it was a rapid game.

```
rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1
1. d4 Nf6 2. c4 g6 3. Nc3 d5 4. cxd5 Nxd5 5. e4 Nxc3 6. bxc3
Bg7 7. Bc4 c5 8. Ne2 Nc6 9. Be3 O-O 10. O-O Qc7 11. Rb1 Rd8
12. Bf4 Be5 13. Bxe5 Nxe5 14. Bb3 Ng4 15. Ng3 Qf4 16. h3 Nf6
17. e5 Nd5 18. Ne2 Qe4 19. Ng3 Qf4 20. dxc5 Be6 21. Qd4 b6
22. Ne2 Qf5 23. cxb6 Nxb6 24. Qf4 Rac8 25. Qxf5 Bxf5 26. Rbd1
Bd3 27. Rfe1 a5 28. Nf4 Bc4 29. Rxd8 Rxd8 30. Re4 Bxb3 31. axb3 Rd1
32. Kh2 Rb1 33. c4 Rxb3 34. c5 Nd7 35. c6 Nb6 36. Rd4 Rc3
37. Nd5 Nxd5 38. Rxd5 Rxc6 39. Rxa5 Rc4 40. Kg3 e6 41. f4 h6
42. Kf3 Rc3 43. Kf2 g5 44. fxg5 hxg5
45. Ra4 Kg7 46. Rg4 Kh6 47. g3 Kh5 48. Ra4 Kg6 49. Ra5 Rd3
50. h4 gxh4 51. gxh4 Rd7 52. Ke3 Rb7 53. Kf4 Rb4 54. Kg3 Kf5
55. Ra7 Rg4 56. Kf3 Rg7 57. Ra5 Rg1 58. Rb5 Ra1 59. Rc5 Ra3
60. Kf2 Ke4 61. h5 Ra8 62. Kg3 Kf5 63. Kh4 Ra4 64. Kg3 Rg4
65. Kf3 Rf4 66. Kg3 Kg5 67. h6 Rg4 68. Kf3 Rh4 69. Rc7 Kg6
70. Rc8 Rxh6 71. Kg4 Rh1 72. Rg8 Kh7 73. Ra8 Rf1 74. Ra2 Kg6
75. Rg2 Rf5 76. Re2 Kg7 77. Kg3 Kf8 78. Re4 Ke7 79. Kg4 Kd7
80. Rd4 Kc6 81. Rd6 Kc7 82. Rd1 Rxe5 83. Rf1 f5 84. Kg5 Kd6
85. Kf6 Re4 86. Rd1 Kc5 87. Rd8 f4 88. Kg5 e5 89. Kg4 Re3
90. Rd1 Kc4 91. Rd2 f3 92. Kg3 e4 93. Kf2 Rd3 94. Ra2 Kd4
95. Ra4 Ke5 96. Kg3 Rd2 97. Ra5 Kd4 98. Ra4 Ke3 99. Ra3 Ke2
100. Kf4 f2 0-1

```
> 4 votes

---
Tags: endgame, blunder
---


# Question
Title: Recent full-point-blunder in a pawn-endgame?
Does anyone know a game since 2014 with both players at least ELO 2400 containing at least one move losing a full point in a pawn endgame ?

In the encyclpopedia for chess endgames, I remember only two examples : Eduard Lasker - Moll , Berlin 1904 and Stahlberg - Tartakower , Paris 1934

# Answer
> 4 votes
Here's an example between players rated 2565 and 2498. I haven't checked this against a tablebase due to the number of pawns, but the move Kb5 changes the Stockfish 6 evaluation from below -100 (at depth 60) to above +11 (at depth 43), which is pretty convincing.

Black has a straightforward win here by first pushing his a-pawn to distract the White king, then capturing White's queenside pawns, then driving his own b-pawn forward to push the White king back, and finally capturing White's kingside pawns and queening one of his own.

But instead Black played Kb5, and White responded by sacrificing a pawn to get his king to d5 to help queen a pawn. At first sight White's sacrifice may not look too promising, as Black queens first and still has an extra pawn. But in fact Black is lost due to the advanced position of White's pawns.

```
[Site "Prague"]
[Date "2014.11.29"]
[Round "3.3"]
[White "B. Heberla"]
[Black "Z. Pakleza"]
[Result "1-0"]
[FEN "8/1p3p2/pPk1pPp1/2P3P1/3K1P2/8/8/8 b - - 4 54"]

1...Kb5 2.f5 exf5 3.Kd5 f4 4.Kd6 f3 5.c6 f2 6.c7 f1=Q 7.c8=Q Qd3+ 8.Ke7 Qd5 9.Qe8+ Kxb6 10.Kf8 Qxg5 11.Kxf7 Qh6 12.Kg8 g5 13.Qe3+ Kc6 14.Qe4+ 1-0

```

---
Tags: blunder, pawn-endgame
---


# Question
Title: how to evaluate the position inside the search function
using PVS Algorithm with Quiet search and zero window search what should the range of the score be (-infinity, infinity ) could it be as small as (-16000,16000) and what should the search return if it's a stalemate or checkmate for me or for the other side ? I tried reading the source code of different engines but there is too much addition(heuristics and such) that make it too difficult for me to understand anything.

the question in another for given this PVS algorithm how and where should I place checking for chaeck/stale mate and what score should I return ?

```
int PVS(alfa,beta,depthleft) {
   if( depthleft <= 0 ) return qsearch(alpha, beta);

// using fail soft with negamax:
make first move
bestscore = -PVS(-beta, -alpha, depthleft-1);
unmake first move
if( bestscore > alpha ) {
   if( bestscore >= beta )
      return bestscore;
  alpha = bestscore;
}

for( all remaining moves ) {
  make move
  score = -PVS(-alpha-1, -alpha, depthleft-1); // alphaBeta or zwSearch
  if( score > alpha && score < beta ) {
     // research with window [alpha;beta]
     score = -PVS(-beta, -alpha, depthleft-1);
     if( score > alpha )
       alpha = score;
  }
  unmake move
  if( score > bestscore ) {
     if( score >= beta )
        return score;
     bestscore = score;
  }
}
return bestscore;
}

```

I wasn't sure where to post this question here or on stack overflow so please migrate it as you see fit

# Answer
> where should I place checking for chaeck/stale mate

Right before `make first move`: there is no first move!
> 1 votes

# Answer
You're supposed to return a negative value based on the ply to the mate. You should place it after the loop for scanning moves. If there's no move, it must be a stalemate or checkmate. Refer to the code in Stockfish as listed below:

```
   // Step 20. Check for mate and stalemate
    // All legal moves have been searched and if there are no legal moves, it
    // must be mate or stalemate. If we are in a singular extension search then
    // return a fail low score.
    if (!moveCount)
        bestValue = excludedMove ? alpha
                   :     inCheck ? mated_in(ss->ply) : DrawValue[pos.side_to_move()];

```

and

```
inline Value mated_in(int ply) {
  return -VALUE_MATE + ply;
}

```
> 0 votes

---
Tags: engines, checkmate, evaluation, programming
---


# Question
Title: Matrix representation of piece position for a chess engine
Looking into a source code of a chess engine, I noticed matrices that represent position of some pieces.

```
knightPos = [
   -200, -100, -50, -50, -50, -50, -100, -200,
   -100, 0, 0, 0, 0, 0, 0, -100,
   -50, 0, 60, 60, 60, 60, 0, -50,
   -50, 0, 30, 60, 60, 30, 0, -50,
   -50, 0, 30, 60, 60, 30, 0, -50,
   -50, 0, 30, 30, 30, 30, 0, -50,
   -100, 0, 0, 0, 0, 0, 0, -100,
   -200, -50, -25, -25, -25, -25, -50, -200
]

```

There are more matrices like this there (also I found the same matrices in other chess engine). It looks like they decode the quality of the piece based on it's position.

Is there any place, where I can read about it, how it is used and how people came up with these numbers?

# Answer
> 1 votes
This is a very common data-structure in chess engine - Piece-Square-Tables.

Refer to https://chessprogramming.wikispaces.com/Piece-Square+Tables for more details.

Basically, it gives a score for a piece on a particular score and it's almost always symmetry (white and black have the same score but flipped).

For example, if I modified the score for knight in the table on d4 to positive infinity. The engine will believe placing a knight is very important, it'll sacrifice it's queen, rooks, bishops just to permanently position a knight on the d4 square.

The values are usually determined by trials-and-errors. Stronger engines such as Stockfish learn the values by playing hundreds or thousands of games, this is known as parameter calibration or automatic tuning.

Refer to https://chessprogramming.wikispaces.com/Automated+Tuning for more details.

CLOP and Texel are two common tuning methods.

---
Tags: engines, evaluation
---


# Question
Title: How to configure scidb to use ChessBase files like ChessBase?
I've just installed scidb, hoping that it would read my ChessBase Fritz Trainer collection.
It was able to read the .CBH files but no video appears. I don't know if that is even supported.
If it is, how can I use it ? If it isn't, how can I mimic this behavior ?

# Answer
> 2 votes
Scidb does not support videos, and I don't think that videos will be supported before the second alpha version is released. Currently Scidb is still a beta (test) version. Whether it is really possible to read the ChessBase videos - this includes also the associated timing data - is still an open question.

---
Tags: software, chessbase, scidb
---


# Question
Title: What is the gnuchess 5.60 "real" rating?
Anyone can say me what is the gnuchess 5.60 "real" rating with a Atom 1.2GHZ and 2GB RAM 32Bits? or something approximate...

According to CCRL, gnuchess 5.60 elo is 2822 ! this website inflate the elo rating of chess engines.

# Answer
Computer rating is relative and has no relation to the Human FIDE. It's over 2800 in CCRL, it could be something else on the FIDE scale. The rating reported is only valid for the specific conditions used by CCRL. Nobody knows for sure the "real" rating on your machine.
> 1 votes

---
Tags: engines
---


# Question
Title: In the Caro-Kann Panov-Botvinnik Attack 5... e6 6. Nf3, what are the differences between 6... Be7 and 6... Bb4 ? Which one is more solid and quiet?
In the Caro-Kann Panov-Botvinnik Attack 5... e6 6. Nf3, I am hesitating between 6... Be7 and 6... Bb4

```
  [StartPly "11"]

  [FEN ""]
  1. e4 c6 2. d4 d5 3. exd5 cxd5 4. c4 Nf6 5. Nc3 e6 6. Nf3 Be7 (6... Bb4)

```

I would like to know all the differences between these two moves.

Which one of these two moves tends to lead on average to the most solid, positional, boring, strategic, slow and quiet positions?

# Answer
As surprising as it sounds, `6...Bb4` is probably going to lead to the quieter game. The reason is that with the bishop on b4, pieces will get traded off on c3.

As an example, the game Najdorf-Portisch 1-0, from 1962 shows some of these ideas. Although the game begins as a `1. d4` game, the position transposes directly to the Panov Botvinnik.

```
[FEN ""]
[Event "Varna"]
[Site "Varna"]
[Date "1962"]
[EventDate "?"]
[Round "3"]
[Result "1-0"]
[White "Miguel Najdorf"]
[Black "Lajos Portisch"]
[ECO "B14"]
[WhiteElo "?"]
[BlackElo "?"]
[PlyCount "43"]

1.d4 d5 2.c4 e6 3.Nc3 Nf6 4.Nf3 c5 5.cxd5 Nxd5 6.e3 cxd4
7.exd4 Bb4 8.Qc2 Nc6 9.Bd3 Nxc3 10.bxc3 Nxd4 11.Nxd4 Qxd4
12.Bb5+ Ke7 13.O-O Qxc3 14.Qe2 Bd6 15.Bb2 Qa5 16.Rfd1 Rd8
17.Qh5 f6 18.Qxh7 Kf7 19.Be2 Qg5 20.Bc1 Bxh2+ 21.Kxh2 Qe5+
22.f4 1-0

```
> 2 votes

---
Tags: opening, theory, strategy, positional-play, caro-kann
---


# Question
Title: What is the Elo rating of a chess computer that can only look 1, 2, 3, ... moves ahead
Has anyone calculated the average Elo rating of a chess computer as a function of the number of half moves or plys ahead it can look. I realise that the Elo is also a function of the choice of move then taken which may differ from engine to engine.

# Answer
There is a paper, which examines this relationship for Houdini 1.5.

http://web.ist.utl.pt/diogo.ferreira/papers/ferreira13impact.pdf

On page 77 you get the relevant table:

```
depth (ply): elo:

20    2894

19    2828

18    2761

17    2695

16    2629

15    2563

…

8     2099

7     2033

6     1966

```
> 13 votes

# Answer
This is an area that academic can write papers on it. The relationships is complicated and might not be quantified.

Essentially, it's a non-linear relationship where the improvement is most obvious in shallow depth. The benefit diminishes as the engine go deeper and deeper in the search.

Reference: https://www.chessprogramming.org/Depth

Look for the "Diminishing Returns" section and you'll know more.
> 4 votes

---
Tags: engines, rating, ply
---


# Question
Title: What happened in this shootout from Houdini?
What happened in this shoouout from Houdini ? Why did the program take so long to mate with the queen and why did it make such unlogical moves. Considering the valuations, I conjecture that the program used precalculated variations, but I am not sure. Beginning with a position king + queen against king, Houdini mates fast even at a very low level.

```
[Event "Stellung ausspielen (Houdini15aw32, 15p"]
[Site "?"]
[Date "????.??.??"]
[Round "?"]
[White "Neue Partie"]
[Black "Houdini 1.5a w32"]
[Result "0-1"]
[SetUp "1"]
[FEN "8/8/8/3ppk2/8/3K1P1P/8/8 b - - 0 1"]
[PlyCount "135"]

1... Kg6 {[%eval -160,15] [%emt 0:00:04]} 2. Kd2 {
[%eval -175,15] [%emt 0:00:00]} d4 {[%eval -227,15] [%emt 0:00:00]} 3. Kd3 {
[%eval -271,15] [%emt 0:00:00]} Kh5 {[%eval -78,15] [%emt 0:00:06]} 4. Ke4 {
[%eval -91,15] [%emt 0:00:00]} Kg5 {[%eval -111,15] [%emt 0:00:00]} 5. f4+ {
[%eval -115,15] [%emt 0:00:07]} exf4 {[%eval -115,15] [%emt 0:00:00]} 6.   h4+ {
[%eval -115,15] [%emt 0:00:06]} Kg4 {[%eval -109,15] [%emt 0:00:01]} 7. h5 {
[%eval -109,15] [%emt 0:00:00]} f3 {[%eval -109,15] [%emt 0:00:00]} 8. h6 {
[%eval -109,15] [%emt 0:00:00]} f2 {[%eval -109,15] [%emt 0:00:00]} 9. h7 {
[%eval -109,15] [%emt 0:00:00]} f1=Q {[%eval -109,15] [%emt 0:00:00]} 10. h8=Q
{[%eval -120,15] [%emt 0:00:00]} Qe2+ {[%eval -130,15] [%emt 0:00:00]} 11. Kd5
{[%eval -130,15] [%emt 0:00:00]} d3 {[%eval -130,15] [%emt 0:00:00]} 12. Qg7+ {
[%eval -130,15] [%emt 0:00:00]} Kf3 {(Kh4) [%eval -141,15] [%emt 0:00:00]} 13.
Qf7+ {(Df6+) [%eval -141,15] [%emt 0:00:00]} Kg2 {
[%eval -141,15] [%emt 0:00:00]} 14. Qg7+ {[%eval -141,15] [%emt 0:00:00]} Kf2 {
[%eval -141,15] [%emt 0:00:00]} 15. Qh6 {[%eval -141,15] [%emt 0:00:00]} Qe3 {
[%eval -142,15] [%emt 0:00:00]} 16. Qh2+ {[%eval -142,15] [%emt 0:00:00]} Ke1 {
[%eval -225,15] [%emt 0:00:01]} 17. Kc4 {(Dh1+) [%eval -244,15] [%emt 0:00:00]}
d2 {[%eval -448,15] [%emt 0:00:01]} 18. Qh1+ {[%eval -448,15] [%emt 0:00:00]}
Kf2 {[%eval -448,15] [%emt 0:00:00]} 19. Qh2+ {[%eval -436,15] [%emt 0:00:00]}
Kf1 {[%eval -440,15] [%emt 0:00:00]} 20. Qh1+ {[%eval -440,15] [%emt 0:00:00]}
Kf2 {(Ke2) [%eval -436,15] [%emt 0:00:00]} 21. Qh2+ {
[%eval -434,15] [%emt 0:00:00]} Kf1 {[%eval -420,15] [%emt 0:00:00]} 22. Qh1+ {
[%eval -434,15] [%emt 0:00:00]} Ke2 {[%eval -434,15] [%emt 0:00:00]} 23. Qg2+ {
[%eval -414,15] [%emt 0:00:00]} Kd1 {[%eval -414,15] [%emt 0:00:00]} 24. Qc6 {
[%eval -414,15] [%emt 0:00:00]} Qg3 {[%eval -414,15] [%emt 0:00:00]} 25. Kb4 {
(Da8) [%eval -425,15] [%emt 0:00:00]} Qd3 {[%eval -420,15] [%emt 0:00:00]} 26.
Ka5 {[%eval -420,15] [%emt 0:00:00]} Qd4 {(Db3) [%eval -998,15] [%emt 0:00:21]}
27. Ka6 {[%eval -1117,15] [%emt 0:00:24]} Ke2 {[%eval -1103,15] [%emt 0:00:03]}
28. Qe6+ {[%eval -1130,15] [%emt 0:00:11]} Qe3 {[%eval -1095,15] [%emt 0:00:01]
} 29. Qa2 {[%eval -1125,15] [%emt 0:00:03]} Kf2 {
(Ke1) [%eval -1163,15] [%emt 0:00:10]} 30. Kb7 {[%eval -2104,15] [%emt   0:00:30]
} Qe2 {[%eval -32695,15] [%emt 0:00:02]} 31. Qa7+ {
[%eval -32685,15] [%emt 0:00:02]} Kf1 {[%eval -32680,15] [%emt 0:00:00]} 32.
Qa3 {[%eval -32678,15] [%emt 0:00:00]} d1=Q {[%eval -32678,15] [%emt 0:00:00]}
33. Qh3+ {[%eval -32678,15] [%emt 0:00:00]} Qg2+ {
[%eval -32678,15] [%emt 0:00:00]} 34. Qxg2+ {[%eval -32676,15] [%emt 0:00:00]}
Kxg2 {[%eval -32672,15] [%emt 0:00:00]} 35. Kc6 {
[%eval -32670,15] [%emt 0:00:00]} Qd4 {(Kf2) [%eval -32671,15] [%emt 0:00:00]}
36. Kb5 {[%eval -32674,15] [%emt 0:00:00]} Kf2 {
[%eval -32674,15] [%emt 0:00:00]} 37. Kc6 {
(Ka5) [%eval -32674,15] [%emt 0:00:00]} Kf3 {
(Ke2) [%eval -32667,15] [%emt 0:00:00]} 38. Kb5 {
[%eval -32683,15] [%emt 0:00:00]} Kg3 {[%eval -32684,15] [%emt 0:00:00]} 39.
Kc6 {[%eval -32686,15] [%emt 0:00:00]} Kf2 {[%eval -32686,15] [%emt 0:00:00]}
40. Kc7 {[%eval -32688,15] [%emt 0:00:00]} Qd5 {
[%eval -32688,15] [%emt 0:00:00]} 41. Kb6 {[%eval -32688,15] [%emt 0:00:00]}
Qc4 {[%eval -32687,15] [%emt 0:00:00]} 42. Ka5 {
[%eval -32687,15] [%emt 0:00:00]} Qb3 {[%eval -32687,15] [%emt 0:00:00]} 43.
Ka6 {[%eval -32688,15] [%emt 0:00:00]} Qb4 {[%eval -32684,15] [%emt 0:00:00]}
44. Ka7 {[%eval -32684,15] [%emt 0:00:00]} Qd4+ {
(Db5) [%eval -32680,15] [%emt 0:00:00]} 45. Kb8 {
(Ka8) [%eval -32679,15] [%emt 0:00:00]} Qc3 {
(Dc5) [%eval -32677,15] [%emt 0:00:00]} 46. Ka7 {
[%eval -32678,15] [%emt 0:00:00]} Qb2 {(Dd4+) [%eval -32679,15] [%emt 0:00:00]}
47. Ka8 {[%eval -32677,15] [%emt 0:00:00]} Qc3 {
[%eval -32677,15] [%emt 0:00:00]} 48. Kb7 {
(Ka7) [%eval -32677,15] [%emt 0:00:00]} Qc5 {[%eval -32676,15] [%emt 0:00:00]}
49. Ka6 {(Kb8) [%eval -32677,15] [%emt 0:00:00]} Qb4 {
[%eval -32678,15] [%emt 0:00:00]} 50. Ka7 {[%eval -32675,15] [%emt 0:00:00]}
Kg1 {(Db2) [%eval -32675,15] [%emt 0:00:00]} 51. Ka6 {
[%eval -32677,15] [%emt 0:00:00]} Kf1 {[%eval -32677,15] [%emt 0:00:00]} 52.
Ka7 {[%eval -32678,15] [%emt 0:00:00]} Qb5 {[%eval -32679,15] [%emt 0:00:00]}
53. Ka8 {[%eval -32680,15] [%emt 0:00:00]} Kg2 {
(Kf2) [%eval -32672,15] [%emt 0:00:01]} 54. Ka7 {
[%eval -32673,15] [%emt 0:00:00]} Kf2 {[%eval -32672,15] [%emt 0:00:00]} 55.
Ka8 {[%eval -32672,15] [%emt 0:00:00]} Qd3 {
(Dd5+) [%eval -32672,15] [%emt 0:00:00]} 56. Kb7 {
(Ka7) [%eval -32672,15] [%emt 0:00:00]} Qf3+ {[%eval -32671,15] [%emt 0:00:00]}
57. Ka7 {[%eval -32672,15] [%emt 0:00:00]} Qc6 {
(Db3) [%eval -32672,15] [%emt 0:00:00]} 58. Kb8 {
[%eval -32672,15] [%emt 0:00:00]} Qc4 {(Dc5) [%eval -32672,15] [%emt 0:00:00]}
59. Ka8 {[%eval -32672,15] [%emt 0:00:00]} Qc3 {
(Db3) [%eval -32672,15] [%emt 0:00:00]} 60. Kb7 {
(Ka7) [%eval -32672,15] [%emt 0:00:00]} Qc5 {[%eval -32672,15] [%emt 0:00:00]}
61. Ka6 {[%eval -32659,15] [%emt 0:00:00]} Ke2 {
(Ke1) [%eval -32650,15] [%emt 0:00:00]} 62. Kb7 {
[%eval -32654,15] [%emt 0:00:00]} Kf3 {[%eval -32650,15] [%emt 0:00:00]} 63.
Ka6 {[%eval -32661,15] [%emt 0:00:00]} Qb4 {[%eval -32761,15] [%emt 0:00:00]}
64. Ka7 {[%eval -32762,15] [%emt 0:00:00]} Qb5 {
[%eval -32762,15] [%emt 0:00:00]} 65. Ka8 {[%eval -32763,15] [%emt 0:00:00]}
Ke4 {[%eval -32763,15] [%emt 0:00:00]} 66. Ka7 {
[%eval -32764,15] [%emt 0:00:00]} Kd5 {[%eval -32764,15] [%emt 0:00:00]} 67.
Ka8 {[%eval -32765,15] [%emt 0:00:00]} Kc6 {[%eval -32765,15] [%emt 0:00:00]}
68. Ka7 {[%eval -32766,15] [%emt 0:00:00]} Qb7# {
[%eval -32766,15] [%emt 0:00:00]} 0-1

```

# Answer
> 1 votes
How did you run the game? Did you run it by a fixed-depth? How much time did you give to the engine? I assume that you gave the engine either too little time or a fixed depth. In this case, the engine might not know the shortest way for a mate, because to the engine any move that doesn't lose the queen is the same. It only starts moving the king, when it sees a mate in its search horizon.

---
Tags: software, houdini, queen-endgame
---


# Question
Title: Looking for the complete game Sibilio-Mariotti, Ravenna 1982
Tim Krabbe shows this game on his record site.

```
[Title "Sibilio-Mariotti, Ravenna 1982"]
[FEN "5k2/1p4pp/4p3/3pP1q1/3P4/7K/7P/8 w - - 0 1"]

```

The game has a stalemate after only 27 moves. I would like to know the complete game. I did not find in chessgames.com, chess365, or my database. Does anybody know the full game?

# Answer
> 3 votes
All games from Tim Krabbe's website are available in the little player on the right side of the page (there is a chessboard, game navigation bar and a box from which the games can be chosen). For the sake of the question and since it is quite an entertaining game, though:

```
[White "Sibilio"]
[Black "Mariotti"]
[Event "Ravenna 1982"]
[fen "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1"]

1. e4 e6 2. Nf3 d5 3. e5 c5 4. b4 cxb4 5. d4 Nh6 6. a3 bxa3 7. c3 Nf5 8. Nxa3 Nc6 9. Nb5 a6 10. g4 Bd7 11. Bg5 Be7 12. gxf5 axb5 13. fxe6 fxe6 14. Rxa8 Qxa8 15. Rg1 Qa3 16. Bxb5 Bxg5 17. Rxg5 Qxc3+ 18. Kf1 O-O 19. Bxc6 Bxc6 20. Kg2 Ba4 21. Qe2 Bc2 22. Ne1 Bxe4+ 23. f3 Rxf3 24. Nxf3 Bxf3 25. Qxf3 Qd2+ 26. Kh3 Qxg5 27. Qf8+ Kxf8 1/2-1/2

```

---
Tags: draw, stalemate, famous-games
---


title: Best chess theory books for beginners

text:
# Question
Title: Best chess theory books for beginners
What are the best chess books regarding theory and such for beginners?

# Answer
> 11 votes
A book often recommended to beginners is Logical Chess: Move by Move by Irving Chernev. It contains 33 games with text explanations for every single move.

Dan Heisman also recommends other books in his web site, here are a few:

* Chess: The Art of Logical Thinking - Neil McDonald
* A First Book of Morphy by del Rosario
* Most Instructive Games of Chess Ever Played - Irving Chernev
* Chess Master vs. Chess Amateur - Euwe and Meiden

\[edit\] Here's a PGN file of Logical Chess that you can play through using a game viewer like Scid vs. PC while you read the book. Or you can just use a regular chess set.

# Answer
> 7 votes
It's a bit old, but I cut my teeth on "Chess Fundamentals" by former world champion JR Capablanca. Moreover, it's one of the few books in the public domain, so you can access it online.

# Answer
> 2 votes
To take the beginner up a notch "My System" by Aron Nimzowitsch ... it goes over basics of theory like open files which even a beginner can get a feeling for. This book will move the person to an advance beginner or to intermediate (with practice). The skills in the book are essential. Here is a link to download the classic: http://www.taflfelag.is/assets/files/Nimzowitsch,.Aron.My.System.(21st.century.ed).pdf The sort of companion to "My System" is "Chess Praxis" which gives games to see the applications of the concepts in "My System". That would probably be a next book. If you want something for the total beginner then something like "A Primer of Chess" by Capablanca Be sure to learn all the basic endgame mating combinations (queen, rook, bishop-bishop, bishop-knight) as well.

# Answer
> 1 votes
Agree with others regarding Nimzowitsch - I would not recommend that to beginners for many reasons. I would add to retrodanny's recommendations, I would also add

* Best lessons of a chess coach by Sunil Weeramantry and Ed Eusebi - joy to read

I would start with Logical Chess Move by Move and then move to Best Lessons (above) and then to others.

# Answer
> 1 votes
I recommend the following :

1. CHESS FOR CHILDREN by Murray Chandler & Helen Milligan
2. WINNING CHESS STRATEGY FOR KIDS by Jeff Coakley
3. THE CHESS KID'S BOOK OF TACTICS by David MacEnulty
4. CHESS OPENING FOR KIDS by John Watson & Graham Burgess
5. THE STEPS METHOD (Learning Chess Step 1 to 6) by Rob Brunia and Cor van Wijgerden

read more click

http://newchessbasics.blogspot.com/2015/03/5-great-chess-books-for-kids.html

# Answer
> 0 votes
A little indirect of an answer here *but* because you mention that you are looking for books strictly for *beginners* I thought this point might be of use to you:

No real theory is needed in the beginning stages of chess. The most rapid chess improvement to be gained for the beginning chess player will come in the form of chess tactics. Studying chess tactics alone will result in huge rating gains. Once you reach an ELO of about 1800 then it becomes necessary to start studying positional theory.

It really is a Maslow's hierarchy type of dynamic. If you match two computers against each other, one with high tactical knowledge and low positional knowledge and the other with high positional knowledge and low tactical knowledge - simulate it 100 times -- the computer with tactical knowledge will still win all the games.

Hope this makes sense :D

# Answer
> 0 votes
Learn Chess by John Nunn is a fantastic book for beginners, do not be fooled by the title

Build up Your Chess 1: The Fundamentals (Yususpov's Chess School) by Artur Yusupov will definitely make you shed your beginner skins!

50 Essential Chess Lessons by Steve Giddins, a very easy book to read, fantastic

# Answer
> 0 votes
*My 60 Memorable Games* is a great book on so many levels. There's something in it for everyone, from beginner to grandmaster. If you want to learn the Ruy Lopez, go over the Ruy Lopez games. (While Fischer was known for the Sicilan, Sicilian opening theory has changed more than Ruy Lopez since the 70's.) It's especially fun to go over Fischer's analyses with an engine, to see if his opinions about his games where really correct or not.

While it isn't the only book on chess to read, it is one of the great classics. If it is the only one you read, you'll still find that it improves your game.

I've seen recommendations for Chernev's *Logical Chess*. That is indeed a good book, one of the few that explains every move. When I was a beginner, I often found it frustrating to go through books and have no idea why a particular move was chosen. If you can get past his gushy style, there's a lot of good insight in there.

---
Tags: learning, books
---


# Question
Title: What openings provide "mini-objectives" in the early game?
As a beginner I've found that it is psychologically really nice playing QGA as white simply because I have a clear task at hand in the early game - namely recapture that pawn. Similarly, hedgehog for black is satisfying because you are aiming for a layout rather than a sequence.

I often find it quite hard to stumble through the early game when there is no clear objective - many openings the objective is simply to "develop pieces onto good squares". I'm not yet good enough to visualise that task so play pretty aimlessly.

What other openings should I look at that have clear, understandable, short term objectives to get you to the mid-game?

# Answer
> 5 votes
Technically speaking ALL openings have an objective other than developing your pieces. For example

Italian Game/Italian Opening goes like so:

```
[fen ""]

1.e4 e5 2.Nf3 Nc6 3.Bc4

```

From this position you would think it's simply development of pieces however that's not the case. In the Italian game, the opening itself for white is pin pointed on the f7 weakness in black's structure, when black played e5 in response to white's e4 it opened up a weakness in the structure which is the f7 pawn. That f7 pawn ends up being a pinned pawn in many cases if the player castles on the king side normally, or even sometimes turns in to a bishop sacrifice if you have a good rook lift and an attack going on (however that's too complicated for a beginner in chess). In short Italian Opening's objective is simple, attack the king side's weaknesses and is an aggressive opening most of the time when it goes into the mid game phase.

You also have the Ruy Lopez one of the most famous openings in the history of chess. The opening focuses on ruining the pawn structure for Black and gaining a potential advantage with the pin on Knight on c6.

You also have the French Defense which is also a famous opening

```
[fen ""]

1.e4 e6 2.d4 d5

```

The entire purpose and reputation of the French Defense is based on defense and counter play. Usually players of the french prefer a closed game, however that's a conversation for another thread. In the french black's objective is usually counter attack on the queen side while white usually focuses his attack on the king side. French defense also a solid pawn structure which upholds its reputation for defense.

I truly can't give you a list since almost every single opening out there has an objective or a reason for every move. Posting more openings and their objectives + explanation would definitely take too long. However I will leave you with these 3 openings that I was able to mention in this long post and hopefully I helped. If you have any further questions feel free to ask and I will attempt to answer as best I can

**Edited part to answer the questions in the comments section :)**

King's Gambit (Polerio/Villemson Gambit line is shown below, not the classic line)

```
[fen ""]

1.e4 e5 2.f4 exf4 3. d4

```

This opening focuses more on offense, with white's move of 2.f4 he is hoping to accomplish mostly 2 things, 1.) ruin the pawn structure (doubled pawns on the f file) and 2. Clear the way to push down the middle. However King's Gambit has 2 variations, Accepted and Denied gambit (accepted is when black takes the f pawn and accepts the sacrifice, Denied is when black continues and ignores the pawn).

If black takes the pawn (which is mostly what white wants) white will in most cases sieze the opportunity and push down the middle with d4 hoping to occupy space and make space for his pieces to enter the game. However in response black usually focuses on the f2 spot weakness where the pawn was sitting before it was sacrificed. Black's objective after the sacrifice is usually have his black bishop hitting that diagonal and unless white can somehow defend it will become a problem (that's why it's called a gambit). From white's point of view however that open f column is also a weapon, it is basically a semi opened column (unless black's f pawn was taken back which would make it a completely open column) for the king side rook. And since King's gambit is usually an open game with bishops this is a dangerous combination.

Here is also the Queen'g Gambit, however instead of me typing the explanation here, you might have a more enjoyable time reading and listening to this http://www.thechesswebsite.com/queens-gambit/

Hope I helped :) If you have even more questions feel free to ask :)

# Answer
> 4 votes
I think this question divides into two parts:

* Openings with "mini objectives" early in the game.
* Openings that go for a layout instead of a sequence.

The second part is easier to tackle: There are a lot of openings, usually called "systems", that go for a certain structure without bothering too much with what the opponent is doing. Some examples:

* The London System
* The Colle-Zukertort
* The Stonewall-Dutch
* The Stonewall with white

Also in many sicilian lines (most notably the dragon) white just castles long and starts to march his kingside pawns --\> sac,sac,mate as Bobby Fischer famously said. But these are much more dependent on move order issues and concrete tactics. You could interpret "long castles" as a mini-objective for white in the English attack, which is almost always achieved by playing f3, Be3, Qd2.

Mini-objective vary from variation to variation, but I think there is one mini-objective that is almost always relevant, especially when playing black: pawn levers.

For example if you play the black side of a QGA, you might go for the pawn lever c5. In a King's Indian black prepares the pawn lever f5, and sometimes c6 (whereas white goes for c5). In a Benoni he goes for b5 and sometimes f5. In a Meran you will always play c5 or e5 at some point, while white usually plays e4, in a Italian or Spanish game white prepares e4, in a French black goes c5 and white hopes for f5 … they are all over the place!

So my advice would be to look out for pawn levers in the openings you play. They should very often provide the mini-objective that gets you from the opening into the middlegame.

---
Tags: opening, strategy, beginner
---


title: Advanced Middle Game Attacking Tactics

text:
# Question
Title: Advanced Middle Game Attacking Tactics
Before I get into the details of my questions, I already know the f, g and h pawn attack tactics, bishops sacrifices such as the greek gift and Lasker's double bishop sacrifice among a few others and of course things such as the isolated queen pawn positions(which is usually something that ends up in the end game part).

So what I am looking for are some advanced middle game tactics, be it from books, online teachers or anything of the sort. I do not have the money to buy the rest of Daniel King's power play series and I already exhausted the few books I have. Any help would be appreciated.

# Answer
The attacking manual by Jacob Aagaard might be just what you are looking for. I enjoyed it a lot. It contains instructive games and exercises.

Other good books on attacking: Spielmann, The Art of Sacrifice, Vukovic, The Art of Attack, Christiansen, Storming the barricades.
> 2 votes

---
Tags: learning, strategy, tactics, middlegame, sacrifice
---


# Question
Title: How can the moves from this pawn endgame study be found without a computer?
```
[FEN "8/1p5k/1P1p4/3p4/3Pp2p/2K1P2p/7P/8 w - - 0 0"]
[PlyCount "21"]

1. Kb2 Kg8 2. Ka1 Kf8 3. Ka2 Ke7 4. Kb3 Kd7 5. Kb4 Kc6 6. Ka5
Kd7 7. Kb4 Ke6 8. Kc3 Kf6 9. Kc2 Kg5 10. Kd1 Kg4 11. Ke2

```

In this great study from Ebersz, white can reach a draw, but only with extreme accurate play. The given variation is one possible. All white moves are forced, any other king move would lose. Suppose, white is in such a position in a practical game, of course without access to electronic topics. Can the correct squares be found out manually ? I know the theory of countersquares, but it seems to be extremely difficult.

How can white save this game without too much efforts ?

# Answer
> 11 votes
Some of the corresponding squares are quite easy to work out, especially if you write things down (not allowed in a real game).

First of all, it is clear that

`a5` corresponds to `c6`.

Black can move from `c6` to `g4` in 4 moves. The only square that stops black's invasion and is 4 moves away from `a5` is `e2`, so

`e2` corresponds to `g4`.

The squares on the paths in between need to correspond, so

`b4` corresponds to `d7`,

`c3` corresponds to `e6`,

`d2` corresponds to `f5`.

It then follows that

`b3` corresponds to `e7`,

`c2` corresponds to `f6`,

`d1` corresponds to `g5`.

Hence,

`b2` corresponds to `f7`,

`c1` corresponds to `g6`,

`b1` corresponds to `g7`.

The trickiest part is to show that `a3` corresponds to `e8`. When the black king is on `e8`, it threatens to go to `d7`, `e7` or `f7`, corresponding to `b4`, `b3` and `b2` for white. Therefore the white king needs to be on `a3` or `c3`, but `c3` is the wrong square. Why? Because after a subsequent `Kd8` move form black, white would be in zugzwang. Black can still go to `d7`or `e7`, so white needs to go to a square adjacent to `b4` and `b3`. Such a square is not available from `c3`.

So,

`a3` corresponds to `e8`,

and therefore

`a4` corresponds to `d8`,

`a2` corresponds to `f8`

`a1` corresponds to `g8`.

Now the solution can be explained. In the diagram position Black can go to `g6`, `g7` or `g8`, so white needs to have `c1`, `b1` and `a1` available. Therefore `1. Kb2!`

---
Tags: endgame, pawn-endgame, studies
---


title: Soundness of the King's Indian Defence

text:
# Question
Title: Soundness of the King's Indian Defence
It is rarely seen at top level nowadays, but in the times of Fischer and Kasparov vs. Karpov matches, it was a very popular opening for Black.

I heard that Kramnik made Kasparov stop playing KID and that the Bayonet attack is one of the main reasons that KID is not played so often anymore.

Is the KID considered to be unsound at the top level today? What are the key games that caused this shift in popularity of the KID?

# Answer
> 2 votes
Actually the King's Indian has seen a recent rise in popularity. For a few years now, players like Nakamura and Radjabov have revitalised the opening. And if you take a look at the very recent top level games it is striking how many top players gave it a try: Nakamura, Jobava, Grischuk, Giri, Radjabov, Kasimdzhanov, Bacrot and quite consistently Ding Liren, just to name a few.

Those are all games from 2015 and the list reads like a who's who in top level chess. So there certainly is no big theoretical issue, that would dissuade black from playing the King's Indian.

One of the hottest lines right now is the 6.h3 line (white's choice in most of the games I linked), apparently Aronian introduced some tricky ideas for white in this variation (according to Seirawan).

I have heard this Kramnik-Bayonet-story before, but I'm not sure how close it is to the truth. Kasparov himself said, that he stopped playing the King's Indian because it became too much work to keep up with two ultra-sharp black defences (The other being the Najdorf). A few years ago the Bayonet-variation was still widely played (Nakamura scored some impressive wins against it), but for now the focus seems to have shifted to 6.h3.

# Answer
> 1 votes
The King's Indian is very non-symmetric agressiv opening. It was popularized by player like Kasparov or Fischer always looking for big complication even with Black.

In today's chess, players with black are more looking for very solid opening play and try to win a long run game. But still many top level grandmaster are playing it like Nakamura, Giri, Ding Liren, Bacrot, Vachier-Lagrave ... Of course most of the time to avoid preparation they have other weapons than King's Indian like Grunfeld, Benoni or Dutch.

Also the KID doesn't seem unsound as "Quality Chess", which is an editor reknowned for the quality of the books they publish, is publishing a series by GM Vassilios Kotronias on the King's Indian.

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Tags: opening, theory, kings-indian
---


# Question
Title: Is it the right choice to lose the queen for two rooks?
Is it the right choice to lose the queen for two rooks for this situation?

# Answer
If it is white to move, he should probably play c3, Qb2 and only then Rxb7, not even allowing black the choice to trade the queen for two rooks. I don't see how black can defend against this and the resulting position should be winning for white. Maybe a computer will tell you that immediately taking on b7 is even stronger, but for a human this entails a certain amount of risk, whereas c3,Qb2,Rxb7 keeps complete control.

If it is black to move, he should probably play Kb8 with idea of playing Ka7 and Rb8, defending against c3, Qb2, Rxb7. In that case Rxb7 might be whites best choice and it looks indeed like a strong continuation. Something like 2.Rxb7 Qxb7 3.Rxb7 Kxb7 4.Qb4 Ka7 5.c6 Rb8 6.Qc5+ Ka8 7.Qxc4 Ka7 8.Qc5+ Ka8 9.Qe7 Rc8 would also result in a position where white is in complete control and can push his extra pawns with c4, d5 and maybe intrude with the king h4, Kh2,Kg3,Kf4,Kg5,Kf6.

Not taking the rook after Rxb7 is not really a choice for black. In that case he would just be lost without any counterchances.
> 4 votes

# Answer
The answer is IN THIS position NO (if you're black) However it's a forced win anyways

http://en.lichess.org/jEK9MC3O#10

Here is the game's result against a lvl 6 stockfish (I played against it) which is just over 2000 rating. It's a won game due to the pawn structures. Keep in mind stockfish rating goes up and down depending on people's wins and loses so it might not be 2000 it may be more like 2100 or even lower like 1900.

Of course you can ignore the latter part of the game since the AI on the site doesn't resign :)

Also, for the most part trading 2 rooks for a Queen is considered as material loss instead of gain. Mathematically speaking, a Queen is worth 9 points, a rook is worth 5, meaning both rooks are worth a total of 10.

And you have a lot of proof for this, a very simple example is King + 2 rooks vs King + Queen... This is a draw, and I am talking about a fully empty board just these pieces on, it's a forced draw...

However just like in this position, sometimes the location of rooks and pawn structure of the game makes this sacrifice a game winner... Black can't really defend against anything white throws at him, unless white blunders heavily.

And as you can see from the game link you have the explanation of the advantage of each move played after the sacrifice.

Hope I helped.
> 1 votes

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Tags: queens, rooks
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# Question
Title: In the Caro-Kann Panov-Botvinnik Attack which move tends to lead to the most solid, positional, slow, closed, and quiet positions: 5... e6, Nc6 or g6?
In the Caro-Kann Panov-Botvinnik Attack, after 1. e4 c6 2. d4 d5 3. exd5 cxd5 4. c4 Nf6 5. Nc3, which move tends to lead (on average) to the most solid, positional, slow, closed, quiet and strategic positions (the less sharp positions, the positions which contain the less tactics) : 5...e6 or 5...Nc6 or 5...g6 ?

What are all the differences between these three moves? What are the advantages and disadvantages of each of them?

# Answer
> 5 votes
Let me quote very strong GM ( taken from *Lars Schandorff-Grandmaster Repertoire 7 The Caro-Kann* ) :

> The famous Panov variation has always attracted aggressive players with White, and it is easy to understand why. With an active pawn move, White immediately creates tension in the centre and shows that he values the initiative more highly than mere positional matters, such as pawn structure. The Panov often leads to double-edged positions where White has isolated queen's pawn in exchange for fluid piece-play and general activity.

Please note the *The Panov often leads to double-edged positions...* part. I told you this before, and sadly here is the same case : White chooses here whether the struggle will be sharp tactical encounter or quiet strategical "debate".

That being said, let us examine all 3 moves and let us start from `5...g6` :

This is not entirely correct, but may be playable. Black struggles to draw by regaining the sacrificed `d-pawn`. So far White has pleasant advantage in the main lines, but maybe somebody will invent some novelty that will make Black's play fully equal ( I still have my doubts but who knows... ).

As for `5...Nc6` :

This move gives White lots of options to sharpen the game. He can go into Endgame variation where he has small initiative and better piece placement, or he can go into sharp lines with `6.Bg5`. Here lines are very sharp. **You can transpose to more solid lines with `6...e6`** which may be what you want but be warned that *Schandorff* still believes White is slightly better there. Playing **similar** positions as Black, I must agree with him -\> these are very tough to play as Black, at least they were for me. He prefers `6...dxc4` instead.

As for `5...e6`, it might be exactly what you look for, but you really need latest theory here. *Schandorff* says that in the moment of him writing the book ( 2010 ) the Nimzo-Indian plan Karpov invented that starts with `5...e6` lost its appeal. Still, if I were you, I would look thoroughly for these positions as they were solid before. I doubt White can improve the game, so all you will probably need are good opening moves and you will be ready to go! 90% of the time you should be battling against Isolated Queen's pawn which is easier to play as Black... Just "do your homework" first!

I wish I was able to offer you some sample lines with `5...e6` but I have no up-to-date books on that :(

Good luck!

# Answer
> 2 votes
Im fairly new to caro kann myself, and am searching for the exact same answer as the original poster.... looking for a quiet continuation. I think, Nc6 is the best option. After that white can play Nf3 or the sharp Bg5. The main blunting move for black here is Be6, played quite commonly these days at the top level, and kind of unusual at the club/amateur level... so I doubt your opponent would know the best continuations for white thereafter.

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Tags: opening, theory, strategy, positional-play, caro-kann
---


# Question
Title: What are the differences between the major online chess sites that allow to play?
I'm thinking of dedicating some of my free time to learn and play chess in a systematic and serious way and try to participate in a non-Internet tournament in a few months. I will take this activity as a hobby, but still want to keep it serious, cos I know that my progress will determine how much fun the thing will be.

I know that there are many websites that allow you play chess online, but I'm interested in what experienced users have to say about them taking in care my goals. I'm looking for a place that allows me learn, play and test myself giving me a kind of rating from which I could infer with more or less accurateness my FIDE ELO and then decide when I'm ready to spend time participating in a non-Internet tournament.

# Answer
> 1 votes
Nowadays there is really a abundance of good chess servers. And they are all relatively similar. I think you need a site where you can:

* Play blitz chess
* Play correspondence chess
* Do tactics training
* Learn via articles and/or videos

If you want everything on one site, www.chess.com is probably your best bet. As far as I know ICC, chess24, playchess and FICS don't have correspondence games. For beginners it is often hard to play blitz, and even later you might learn more from longer games.

The downside of chess.com is that the players are relatively weak. But if you are just starting out, this is not going to bug you for a few years.

# Answer
> 1 votes
I recommend http://chesstempo.com with all my heart. It is free with no advertisements. The interface allows a large choice of board sizes and figurine fonts. You can play online against other people or against computers of various strengths even when people are not available. You can also do tactics training - the best site for this.

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Tags: learning, tournament, elo, training, online-chess
---


# Question
Title: How many possible positions are there in chess?
How many possible positions are there in chess? Please be exact.

# Answer
Shannon estimated the number of possible positions roughly 10^43. This includes some illegal positions (e.g., pawns on the first rank, both kings in check) and excludes legal positions following captures and promotions.

Taking these into account, Victor Allis calculated an upper bound of 5×10^52 for the number of positions, and estimated the true number to be about 10^50.

Recent results improve that estimate, by proving an upper bound of only 2^155, which is less than 10^46.7 and showing an upper bound 2×10^40 in the absence of promotions.
> 1 votes

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Tags: theory, game-complexity
---


# Question
Title: Did black have a chance to save the rook endgame?
```
[Event "FIDE Women's World Chess Championship"]
[Site "Sochi RUS"]
[Date "2015.03.24"]
[Round "3.2"]
[White "Natalia Pogonina"]
[Black "Marie Sebag"]
[Result "1-0"]
[ECO "D46"]
[PlyCount "134"]
[EventDate "2015.03.17"]
[FEN ""]

1. d4 d5 2. c4 c6 3. Nf3 Nf6 4. Nc3 e6 5. e3 Nbd7 6. Qc2 Bd6 7. Bd3 O-O 8. O-O
e5 9. cxd5 cxd5 10. e4 exd4 11. Nxd5 Nxd5 12. exd5 h6 13. Rd1 Nf6 14. h3 Nxd5
15. Bh7+ Kh8 16. Rxd4 Nf6 17. Bf4 Nxh7 18. Bxd6 Re8 19. Qb3 Kg8 20. Ne5 Qf6 21.
Rad1 Ng5 22. h4 Ne6 23. Re4 Nf4 24. Qa4 b5 25. Qxb5 Be6 26. Qa4 Ng6 27. Nxg6
Qxg6 28. Rde1 Red8 29. Be5 Rac8 30. a3 Kh7 31. Bc3 Bd7 32. Qxa7 Bc6 33. h5 Qg5
34. Qxf7 Bxe4 35. Rxe4 Rd1+ 36. Kh2 Rc5 37. Qg6+ Qxg6 38. hxg6+ Kxg6 39. Re7
Rh5+ 40. Kg3 Rg5+ 41. Kf3 Rd3+ 42. Ke2 Rxc3 43. bxc3 Rxg2 44. Re3 Rh2 45. c4
Rh4 46. Kd3 Rf4 47. c5 Kf7 48. Re2 Ra4 49. c6 Rxa3+ 50. Kd4 Ra1 51. Rc2 Rd1+
52. Ke5 Re1+ 53. Kd6 Rd1+ 54. Kc7 Re1 55. Kc8 h5 56. c7 Re7 57. Kd8 Rxc7 58.
Kxc7 Kf6 59. Kd6 Kf5 60. Rc5+ Kg4 61. f3+ Kxf3 62. Rxh5 Kf4 63. Rh4+ Kf5 64.
Kd5 g5 65. Rh8 Kf4 66. Kd4 g4 67. Rf8+ Kg3 1-0

```

The position after 58.Kc7 is won for white and white did not allow a draw position afterwards. Could Black have saved the rook ending somewhere ?

# Answer
> 3 votes
Yes, Black had a chance to save the game on moves 45, 46, and 48. Her entire plan from 45 to 49 is wrong. She needed to bring her king and leave the rook uncommitted (in various positions) for as long as possible. See the analysis below (thanks to Stockfish 6 x64 in Deep Fritz GUI).

```
[Event "FIDE Women's World Chess Championship"]
[Site "Sochi RUS"]
[Date "2015.03.24"]
[Round "3.2"]
[White "Natalia Pogonina"]
[Black "Marie Sebag"]
[Result "1-0"]
[ECO "D46"]
[PlyCount "134"]
[EventDate "2015.03.17"]
[FEN ""]

1. d4 d5 2. c4 c6 3. Nf3 Nf6 4. Nc3 e6 5. e3 Nbd7 6. Qc2 Bd6 7. Bd3 O-O
8. O-O e5 9. cxd5 cxd5 10. e4 exd4 11. Nxd5 Nxd5 12. exd5 h6 13. Rd1 Nf6
14. h3 Nxd5 15. Bh7+ Kh8 16. Rxd4 Nf6 17. Bf4 Nxh7 18. Bxd6 Re8 19. Qb3
Kg8 20. Ne5 Qf6 21. Rad1 Ng5 22. h4 Ne6 23. Re4 Nf4 24. Qa4 b5 25. Qxb5
Be6 26. Qa4 Ng6 27. Nxg6 Qxg6 28. Rde1 Red8 29. Be5 Rac8 30. a3 Kh7 31.
Bc3 Bd7 32. Qxa7 Bc6 33. h5 Qg5 34. Qxf7 Bxe4 35. Rxe4 Rd1+ 36. Kh2 Rc5
37. Qg6+ Qxg6 38. hxg6+ Kxg6 39. Re7 Rh5+ 40. Kg3 Rg5+ 41. Kf3 Rd3+ 42.
Ke2 Rxc3 43. bxc3 Rxg2 44. Re3 Rh2 45. c4 Rh4 (45... Kf7 46. Rf3+ (46.
c5 Rh4 (46... Rh5) 47. Kd3 (47. Kd2 Ra4 48. c6 ( 48. Kc2 Ra5 49. c6 Ra8
50. Kb3 Rc8 51. a4 Rxc6 52. a5 Rf6 53. Re4 Rxf2 54. a6 Rd2 55. a7 Rd8
56. Rg4 Ra8 57. Ra4 Ke6 {0.00/19}) 48... Ra8 49. Rd3 Ke6 50. Rd7 g5
51. Rh7 Kd6 52. Rxh6+ Kc7 53. Rh3 Kxc6 54. Rd3 Ra4 55. Ke3 Kc5 56. Ke2
Re4+ 57. Kf1 Ra4 {0.60/19}) (47. Rc3 Ke7 48. c6 (48. Rg3 g5 49. Rd3
Ra4 50. Rd6 Rxa3 51. Rxh6 g4 52. f3 Rxf3 53. Rg6 Rc3 54. Rxg4 Rxc5 55.
Rg6 Rc3 56. Rb6 Ra3 57. Rc6 Rg3 {0.00/0}) 48... Kd8 49. Rd3+ Kc8 50.
Rd6 Rg4 51. Rd7 g5 52. Rh7 Re4+ 53. Kd1 Re6 54. f3 Rxc6 55. a4 Rf6 56.
a5 Rxf3 57. Rxh6 Ra3 {0.00/ 19}) 47... Rf4 (47... Ra4 48. Kc2 (48.
Re5 Rxa3+ 49. Kc4 Kf6 50. Re8 Kf7 51. Re2 h5 52. c6 Ra1 53. Kc5 h4 54.
f3 h3 55. f4 Rc1+ 56. Kd5 Kf6 57. Rh2 Rc3 {0. 00/19}) 48... h5 49. Kb3
Ra6 50. Kb4 Re6 51. Rh3 g6 52. a4 Ke7 53. Kb5 Kd7 54. Rd3+ Kc8 55. a5
Re2 56. Rd6 g5 57. f3 Kc7 {1.56/19}) 48. Re2 (48. Re1 Rf3+ 49. Kc4 Rxf2
50. a4 h5 51. Kb3 Rf5 52. Kb4 Rf2 53. a5 Rb2+ 54. Kc4 Rc2+ 55. Kb5 Rb2+
56. Kc6 Ra2 57. Kb6 Rb2+ {0.67/19}) (48. a4 Rxa4 49. Re2 h5 50. f3
h4 51. c6 h3 52. f4 Ra6 53. Rc2 Ra8 54. f5 Kf6 55. c7 Rc8 56. Ke4 h2 57.
Rxh2 Rxc7 {0.00/19}) 48... h5 49. c6 Ra4 50. c7 Ra8 51. Rc2 Rc8 52.
Ke4 Ke6 53. Kf4 g6 54. Kg5 Kd7 55. Kxg6 h4 56. Kg5 h3 57. Rc3 Rh8
{1.37/19}) (46. a4 Rh5 47. Ra3 (47. Kd2 Rf5 48. Kc3 (48. Ra3 Ke7 49. f3
Kd6 50. a5 Rf7 51. Rd3+ Kc5 52. Kc3 Rf5 53. a6 Rf7 54. f4 Rxf4 55. a7
Rf8 56. Rd1 Ra8 57. Rd7 g6 {0.00/ 19}) 48... Rxf2 49. c5 g5 50. Kb3
Rf6 51. Kc4 g4 52. a5 h5 53. Kb5 h4 54. c6 Rh6 55. c7 Rh8 56. Rd3 Rc8
57. Rd4 Rxc7 {0.00/19}) (47. Rf3+ Ke6 48. Rg3 ( 48. Rb3 Ra5 49. Rb6+
Kf7 50. Rb4 h5 51. Kd3 h4 52. Ke4 g5 53. Rb7+ Ke6 54. Rb6+ Ke7 55. Rb7+
Ke6 56. Rb6+ Ke7 57. Rh6 Rxa4 {0.00/19}) 48... Kf6 49. Ra3 Ra5 50.
Kd3 Ke7 51. Kc3 Rf5 52. Ra2 Kd6 53. Kb4 Rf7 54. Rd2+ Kc6 55. a5 Rb7+ 56.
Kc3 Ra7 57. Ra2 Kc5 {0.34/19}) 47... Ra5 48. Kd2 (48. Kd3 Ke7 49. Kc3
Rf5 50. Ra2 Kd6 51. Kb4 Rf7 52. a5 Rb7+ 53. Kc3 Kc5 54. a6 Ra7 55. f4
Kb6 56. Kd4 Rxa6 57. Rg2 Ra7 {0.29/19}) 48... Ke6 {0.50/29} 49.
Kc3 Kd6 50. Kb4 Ra8 51. c5+ Kc6 52. Re3 h5 53. Re6+ Kd5 54. Rd6+ Ke5 55.
Rd1 h4 56. c6 h3 57. Kb5 Rb8+ {2.55/19}) (46. Rb3 Rh4 47. Rb4 (47.
Rc3 Rh1 48. Ke3 (48. Kd3 g5 49. Ke4 Ke6 50. a4 Kd6 51. a5 Kc5 52. Rf3
Ra1 53. Rf6 Ra2 54. f3 Kxc4 55. Rxh6 Rxa5 56. f4 gxf4 57. Kxf4 Ra8
{0.00/0}) 48... Ke7 49. Kd4 Kd6 50. Rf3 Rd1+ 51. Rd3 Ra1 52. Rg3 Rd1+
53. Kc3 Rc1+ 54. Kd3 Rd1+ 55. Kc2 Rd4 56. Kc3 Kc5 57. Rxg7 Rxc4+
{0.24/19}) (47. Rf3+) 47... Rh3 48. f3 (48. Rb7+ Kf6 49. f3 Rh1 50. Ke3
Ra1 51. Ra7 h5 52. Ra6+ Ke7 53. Kf4 Rc1 54. Rc6 Kd7 55. Rc5 Kd6 56. Rxh5
Rxc4+ 57. Ke3 Rc3+ {0.00/19}) 48... h5 49. a4 Rh2+ 50. Kd3 Ra2 51.
c5 Ke6 52. Kc4 g5 53. Kb5 h4 54. c6 Rc2 55. Rb1 Kd6 56. Rd1+ Kc7 57.
Rd7+ Kc8 {0. 93/19}) (46. Re5 Rh3 47. f3 (47. a4 Rc3 48. Rc5 (48. c5
Ra3 49. f3 Rxa4 50. Kd3 Ra1 51. Kc4 Kf6 52. Re8 Rc1+ 53. Kd4 h5
{0.00/19} 54. Rf8+ Ke6 55. Re8+ Kf6 56. Rf8+ Ke6 57. Re8+ Kf6 {0.00/19})
48... Ke6 49. a5 Kd6 50. Kd2 Rf3 51. Rd5+ Ke6 52. Rd8 Rf5 53. a6 Rxf2+
54. Kc3 Ra2 55. Ra8 Kd6 56. Kd3 Kc6 57. a7 h5 {0. 00/19}) (47. Ra5
Rc3 48. Ra7+ (48. a4 Rxc4 49. Ra7+ Kf6 50. a5 Ra4 51. a6 Ke5 52. Ra8 Kd5
53. a7 Kc6 54. Rc8+ Kb7 55. Rg8 Kxa7 56. Rxg7+ Kb6 57. f3 Kc6 {
0.00/19}) 48... Kf6 49. a4 Rxc4 50. a5 Ra4 51. a6 Ke5 52. Ra8 Kd5 53. a7
Kc6 54. Rc8+ Kb7 55. Rg8 Kxa7 56. Rxg7+ Kb6 57. f3 Kc6 {0.00/19})
47... Kf6 48. Re3 (48. Re8 Rh1 49. a4 Ra1 50. Ra8 h5 51. f4 Ra3 52. c5
Ke6 53. Re8+ Kd5 54. Re5+ Kc6 55. Rxh5 Rxa4 56. Kf3 Rc4 57. Kg4 Rxc5
{0.04/19}) 48... h5 49. c5 Rh2+ 50. Kd1 Rb2 51. c6 Rb8 52. a4 Rc8 53.
Rc3 Ke6 54. Rc5 g6 55. a5 Kd6 56. Rg5 Rg8 57. Ke2 Re8+ {0.18/19})
(46. Rc3 Rh1 47. c5 (47. Ke3 g5 48. Kd4 ( 48. c5) 48... h5 49. Ke5 g4
50. c5 Ke7 51. Kf4 Kd7 52. f3 Rh3 53. a4 Kc6 54. a5 Rxf3+ 55. Rxf3 gxf3
56. Kxf3 Kb5 57. a6 Kxa6 {0.00/1}) (47. f4 Ke6 48. Re3+ (48. Kf2 Kd6
49. a4 Ra1 50. Rg3 g5 51. fxg5 hxg5 52. Rxg5 Rxa4 53. c5+ Kc6 54. Ke3
Rc4 55. Rg1 Kxc5 56. Ra1 Kd6 57. Kd3 Rg4 {0.00/0}) 48... Kf5 49. Rc3
Ke6 50. Kf2 Kd6 51. Rg3 g5 52. Rd3+ Ke6 53. a4 Ra1 54. fxg5 hxg5 55. c5
Rxa4 56. Rg3 g4 57. Re3+ Kd5 {0.00/19}) 47... Ke7 48. Rg3 (48. Rb3)
48... g5 49. a4 Ra1 50. Rh3 Rxa4 51. Rxh6 g4 52. Kf1 Rc4 53. Rh7+ Kd8
54. f3 gxf3 55. Rh2 Rxc5 56. Rh7 Rd5 57. Kf2 Rf5 {0.00/0}) 46... Ke6
47. Rg3 (47. a4 Rh5 48. Re3+ (48. Rg3 Ra5 49. Rxg7 Rxa4 50. Rg4 Kf5 51.
Rh4 Kg5 52. Re4 h5 53. Kf3 Kf5 54. Rd4 Ra3+ 55. Ke2 Rc3 56. f3 Kg5 57.
Kd2 Rxf3 {0.00/19}) 48... Kd6 49. Rg3 Ra5 50. Rxg7 Rxa4 51. Kd3 Ra3+
52. Ke4 Rc3 53. Rg6+ Kd7 54. Kd5 Rf3 55. Rg7+ Kc8 56. Rg2 Kd7 57. Ke4
Rc3 {0.06/19}) (47. Rf8 Rh3 48. f3 (48. a4 Ra3 49. Ra8 Kd6 50. a5
Kc5 51. a6 Kb6 52. Rb8+ Kc5 53. Rc8+ Kb6 54. Rg8 Rxa6 55. Rxg7 Kc5 56.
f4 Kxc4 57. f5 Kd5 {0.00/19}) 48... Rh2+ 49. Ke3 Ra2 50. Ra8 h5 51.
a4 Ra3+ 52. Kf2 Ke5 53. a5 Kf4 54. c5 Ra2+ 55. Ke1 h4 56. c6 h3 57. c7
h2 {0.00/19}) 47... Kf6 48. Ke3 (48. a4 Rh5 49. Ra3 Ra5 50. Kd3 Ke7 51.
Ra1 Kd6 52. Kd4 Rf5 53. Rd1 Kc7 54. Rd2 h5 55. Re2 h4 56. Ke4 Rc5 57.
Rc2 Kc6 {0.10/19} ) 48... Rh1 49. Ke4 h5 50. c5 Rc1 51. Kd5 h4 52. Rf3+
Ke7 53. Rh3 g5 54. f4 Kf6 55. c6 gxf4 56. Rxh4 Kg5 57. Rh2 f3 {2.56/19})
(45... Kf6 46. a4 (46. c5 Rh4 47. Kd3 Ra4 48. Re8 Rxa3+) 46... Rh5 47.
Ra3 Ra5 48. Kd3 Ke6 {0.63/29}) (45... Rh1 46. Kd2 Rb1 (46... Kf6 47. c5
Rb1 (47... Rh5 48. c6 Ra5 {2.01/29}) 48. Kc3 h5 {1.07/29}) (46... Kf7
47. c5 Rb1 (47... Rh5 48. c6 Ra5 {1.75/29}) 48. a4 h5 {1.40/29}) 47. c5
Kf7 (47... Kf6 48. Kc3 h5 {1.11/29}) 48. Kc3 g5 {0.60/29}) 46. Kd3 Rf4
({Stockfish 6 64:} 46... Kf7 47. Kc3 (47. Rf3+ Ke7 (47... Ke6 48. a4
(48. Kc3 Rh1 49. a4 g5 50. a5 h5 51. Kb4 g4 52. Ra3 Kd6 53. a6 Rb1+ 54.
Kc3 Rb8 55. Ra5 h4 56. Rg5 h3 57. Rxg4 Rh8 58. Rg1 h2 59. Rh1 Kc6 60.
Kd4 Kb6 61. f4 Kxa6 62. f5 Kb7 63. f6 Kc6 64. Ke4 Kc5 65. f7 Kxc4
{0.57/37}) 48... Rh1 {0. 68/29}) 48. a4 Rh1 {0.56/29}) (47. c5 Rf4 48.
a4) 47... Rf4 (47... Rh2 48. Rf3+ Ke6 {1.17/29}) 48. c5 g5 {0.69/29})
(46... Kf6 47. a4 Rf4 (47... h5 48. Kc3 Rh1 {2.19/29}) 48. Kc3 Rxf2
{1.61/29}) (46... h5 47. c5 Kf7 (47... Ra4 48. c6 Kf7 { 1.26/29}) 48. c6
Ra4 {1.25/29}) 47. c5 Kf7 (47... h5 48. c6 Rf8 {7.31/29}) 48. Re2 Ra4
(48... Rf6 {2.98/29}) 49. c6 Rxa3+ (49... Ra6 50. Rc2 Ra8 $18) 50. Kd4
Ra1 51. Rc2 {0} Rd1+ 52. Ke5 Re1+ 53. Kd6 Rd1+ 54. Kc7 Re1 (54... Rb1
55. Kd7 Rd1+ 56. Kc8 Rb1 57. c7 Ke7 58. Ra2 g5 59. Ra7 Kf6 60. Rb7 Rc1
61. Kb8 Kf5 62. c8=Q+ Rxc8+ 63. Kxc8 h5 64. Rb5+ Kf4 65. Kd7 h4 66. Ke6
g4 67. Rh5 h3 68. Rf5+ Ke4 69. Rf6 Kd3 70. Kf5 h2) (54... h5 55. Rb2
(55. Kc8 h4 56. c7 h3 57. f4 (57. f3 g6 58. Kb7 h2 59. Rxh2 Rb1+ 60. Kc6
Rc1+ 61. Kd7 Rd1+ 62. Kc8 Rb1 63. f4 Rb4 64. Rd2 Ke7 65. Rd7+ Ke8 66.
Rd6 {123.44/19}) 57... g6 (57... Kf6 58. Kb8 Rb1+ 59. Ka8 (59. Ka7 Ra1+
(59... h2 60. Rc6+ Kf7 61. c8=Q Ra1+ 62. Kb6 Rb1+ 63. Ka5 Ra1+ 64. Kb4
Rb1+ 65. Ka3 Ra1+ 66. Kb2 {123.47/19}) 60. Kb7 Rb1+ (60... h2 61. Rxh2
Rb1+ 62. Kc8 g6 63. Rc2 Ke7 64. Re2+ Kf6 65. Re5 Kg7 66. Kd7
{123.44/19}) 61. Kc6 h2 62. Rxh2 Rc1+ 63. Kb7 Rb1+ 64. Kc8 Ke7 (64...
Kf5 65. Rg2 Rd1 66. Rxg7 {123.45/19}) 65. Rg2 (65. Re2+ Kf7 66. Re5
{123.44/19}) 65... Kf7 66. Rg5 {123.44/19} (66. Rd2 Ke8 67. Rd8+ Kf7 68.
Rd7+ Ke8 69. Rxg7 Rd1 70. Rg6 Rb1 71. Re6+ Kf7 72. Re5 Kg7 73. Kd7 Rd1+
74. Kc6 Rc1+ 75. Rc5 Rh1 76. c8=Q Rh6+ 77. Kb7 Rf6 78. Rc7+ Rf7 79.
Rxf7+)) 59... Ra1+ 60. Kb7 h2 61. Rxh2 Rb1+ 62. Kc8 Rc1 63. Rh5 g6 64.
Re5 Rc4 65. Kb7 Rb4+ 66. Kc6 {123.48/19}) 58. Kb7 Rb1+ 59. Kc6 h2 60.
Rxh2 Rc1+ 61. Kd7 Rd1+ 62. Kc8 Rb1 63. Rc2 Ke7 64. Rc5 Ke8 65. Re5+ Kf8
66. Kd7 {123.45/19 White checkmates Black in nine moves}) 55... h4 56.
Kb8 (56. Kb7 h3 57. f3 Rc1 58. c7 Kf6 59. Rh2 Rb1+ 60. Kc8 g6 61. Rxh3
Kg7 62. Rh4 Kf6 63. Rd4 Ke7 64. Rd7+ Ke8 65. Rd6 Ke7 66. Rxg6 {123.44/19
White checkmates Black in fifteen moves}) 56... h3 57. Rb7+ Kf6 58. c7
Rc1 59. c8=Q Rxc8+ 60. Kxc8 g5 61. Rb3 g4 62. Rb5 Kg6 63. Kd7 Kh6 64.
Kd6 Kg6 65. Ke6 Kh6 66. Kf6 { 123.50/19 White checkmates Black in eleven
moves}) 55. Kc8 h5 56. c7 Re7 57. Kd8 Rxc7 58. Kxc7 Kf6 59. Kd6 Kf5 60.
Rc5+ Kg4 61. f3+ {deflection} Kxf3 62. Rxh5 Kf4 63. Rh4+ Kf5 64. Kd5
g5 65. Rh8 Kf4 66. Kd4 g4 67. Rf8+ Kg3 1-0

```

Probably GM Sebag calculated that she could win the outside a-pawn, but did not consider that this plan would lead to a lost rook and pawn endgame. Or, she got to that point, saw that 49...Rxa3+ was losing either way, so she opted to go for tactical chances.

---
Tags: endgame, rook-endgame
---


# Question
Title: When a pawn promotes, does the new piece go to the promotion square, or the home square of piece type it promoted to?
When a pawn promotes, does the new piece go to the promotion square, or the home square of piece type it promoted to? In other words, if a pawn promotes to a queen, does the queen go back to the square where the queen starts?

# Answer
> 5 votes
The promoted piece replaces the pawn on the square that the pawn moved to (the 8th rank for White, the 1st rank for Black).

From the FIDE Laws of Chess, (emphasis mine):

> 3.7.e. When a player, having the move, plays a pawn to the rank furthest from its starting position, he must exchange that pawn as part of the same move for a new queen, rook, bishop or knight of the same colour **on the intended square of arrival.**

---
Tags: rules, pawn-promotion
---


# Question
Title: Why doesn't the black bishop just capture the white knight?
In a game of mine, the below position emerged.

```
[FEN "r1bqkb1r/2pp1ppp/p1p2n2/4N3/4P3/2N5/PPPP1PPP/R1BQK2R b KQkq - 0 1"]

```

It is Black to move. The computer suggests the move 6... Bd4, and then it suggests 7. O-O for White. Why doesn't the black bishop just take the white knight on e5?

# Answer
Black could take the knight on e5, but then after d4 the bishop doesn't have any good squares. If he tries to retreat to d6, knight and bishop will be forked with e5. In the end white will have better development and better central control, it definitely looks like a ready-made attacking position for white.

```
rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1
1.e4 e5 2.Nf3 Nc6 3.Bb5 a6 4.Bxc6 bxc6 5.Nxe5 Nf6 6.Nc3 Bc5 7.a3 Bd4
8.O-O Bxe5 9.d4 Bd6 10.e5

```
> 6 votes

---
Tags: analysis, positional-play
---


# Question
Title: King's Indian Attack plans for White after Black plays ..dxe4 and ..e5
I always play the King's Indian Attack against the French Defense. Most of the time, I get the position below and I couldn't think of good plans. What are the best ways for White to continue? I don't know where to put my Queen, the d2 Knight, and the Dark-squared Bishop. I am also afraid of the a- and b-pawns of Black when Black starts to move them forward.

I play the KIA because I like closed or semi-closed positions. I don't really like open games. But my opponent has started to open the game by playing this position always.

```
rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1
1. e4 e6 2. d3 d5 3. Nd2 c5 4. g3 Nc6 5. Bg2 Nf6 6. Ngf3 Be7 7. O-O O-O 8. Re1 dxe4 9. dxe4 e5

```

# Answer
> 7 votes
This is my first time answering a question, so i hope that will be all right :)

First of all, the position appearing on the board is also reached via this move order: **1. Nf3 d5 2. g3 c5 3. Bg2 nc6 4. O-O e5 5. d3 Nf6 6. Nbd2 Be7 7. e4 dxe4 8.dxe4** and it's a tempo up for black, and the extra move might be important. And secondly we might reach this position with colors reversed: **1. d4 Nf6 2.c4 g6 3. Nc3 Bg7 4.e4 d6 5. Nf3 O-O 6. Be2 Nbd7 7. O-O e5 8. dxe5 dxe5** etc. And it's very important to notice that the examination of similar positions provides complete understanding of ideas.

Bypassing the move order and transposition issues, I would like to mention the related article named "The King's Indian Attack (from White's Viewpoint)" (page 142) on the excellent book Opening Preparation by Dvoretsky (1996), Dvoretsky came to the conclusion that this exchange (**...dxe4** and **...e5** by Black) is dubious. The reasoning behind Dvoretsky's assessment is:

> *"Not a good exchange. White now has a clear plan for playing on the weaknesses c4, d5 and f5."*

In the game (which cannot be found in databases) **Dvoretsky - Rogozhnikov, Moscow 1965** White executes his plan by playing, **c3**, **Qc2**, **Nf1** and exchanging the defender of d5 square by **Bg5-Bxf6** and after **Ne3**, **Bf1** and **Bc4**, and exchanging the best defender, the light-squared bishop on e6. It should be noted that Dvoretsky's opponent defended weakly and lost after a beautiful positional squeeze. But it's not clear how White will react after the correct a timely **...h6** and countering the White's plan by trying to push **...c4** by **...b5** or **...Na5** Maybe the answer is the mixture of the whole ideas given, let's say, **Nc4(Nf1)-Ne3** and **Nf5** and after an exchange on f5 to take with exf5 and play with the strong bishop g2 and full control on the light squares. There are many typical master games with both colors. You might want to search the other transpositional options in order to achieve complete understanding of the ideas, because there are hundreds of master games beginning from those positions with both colors. I hope I might be able to help you.

---
Tags: strategy
---


title: Mate Prevails - Chess Rule

text:
# Question
Title: Mate Prevails - Chess Rule
Is "Mate Prevails" not an FIDE rule? I couldn't see it in the FIDE website but I heard about it from many players.

**UPDATE:** "Mate Prevails" is a claim some players make that they win the game after 'flag fall' if they can force a checkmate in one move.

# Answer
If you make a checkmating move *before your flag falls*, but then your flag falls before you press the clock, you win. The relevant FIDE rules (emphasis mine) are:

> 5.1.a. The game is won by the player who has checkmated his opponent’s king. **This immediately ends the game**, provided that the move producing the checkmate position was in accordance with Article 3 and Articles 4.2 – 4.7.
>
> 6.2.a. During the game each player, having made his move on the chessboard, shall stop his own clock and start his opponent’s clock (that is to say, he shall press his clock). This “completes” the move. **A move is also completed if the move ends the game** (see Articles 5.1.a, 5.2.a, 5.2.b, 5.2.c, 9.6a, 9.6b and 9.7).
>
> 6.3.a. When using a chessclock, each player must **complete** a minimum number of moves or all moves in an allotted period of time.
>
> 6.9 Except where one of **Articles 5.1.a**, 5.1.b, 5.2.a, 5.2.b, 5.2.c applies, if a player does not complete the prescribed number of moves in the allotted time, the game is lost by that player.
> 11 votes

# Answer
It's not a real rule in FIDE rules. Seems like an anachronism.
> -3 votes

---
Tags: chess-variants, online-chess, correspondence-chess
---


# Question
Title: Should playing chess against yourself always end up in a draw?
You play against yourself, using your own opening repertoire. Thus by playing both White and Black, you reach positions that should be fairly equal, and then you continue to play both sides, obviously knowing each sides' plans. Should the game always end in a draw? How often is White expected to win?

# Answer
> 5 votes
No.

When you are playing seriously against yourself, you still have to commit to moves. After making the move you start analysing again and see things you previously have not seen, and you may discover an error in the moves you have already made and the game becomes a win for one of the sides you play.

Or you may find a winning way without really catching an error in the previous moves.

Note that there are no secret plans in chess, the full truth is always on the board. It is up to you to read the board and draw the best consequences of that reading.

# Answer
> 1 votes
I could probably beat myself because sooner or later I'd make a blunder that I'd spot the second I'd played it. That would allow me to exploit the blunder with the other pieces.

# Answer
> 0 votes
It depends on how good you are. (The worse you are, the more likely that you could make a mistake as one side and then later see how to exploit it as the other.) Almost all skilled players believe that the game of chess is a draw given best play by both sides.

---
Tags: draw
---


# Question
Title: Can Grandmasters beat computers when given time-odds?
For eg., if a grandmaster is given 10:1 time odds, will he be able to beat a computer? For eg, if the GM is given 120 minutes for the entire game and the computer is given 12 minutes? If not 10:1 times odds, then please mention what time odds would be required for a GM to beat a computer.

# Answer
Yes. A grandmaster or a team of grandmasters can hold a draw or win against an engine when given time odds.

I think that there is a minimum time control at which an engine can perform equally good or better than a grandmaster (without time odds). I guess this number is somewhere around 2 or 3 minutes for the whole game.

Let's say for simplicity that it is 5 minutes. So the engine needs 5 minutes for the whole game to perform at a decent level. Now, how many minutes does a grandmaster need to match an engine that has 5 minutes?

It depends. In the opening, the human player needs to be well prepared. Otherwise, it doesn't matter too much if the player has 5 or 50 minutes for the opening part. In the middlegame, my guess is that the player should avoid sharp positions and go for calm waters to reach an equal or slightly better endgame. Try to keep a healthy pawn structure and find long term advantages.

The endgame is where the player has a good chance of holding a draw or winning the game. In general, the more time for middlegame and endgame, the better. I would say that around 20 minutes for the opening, 40 minutes for the middlegame and 40 minutes for the endgame should give the human player a fair chance. That gives a 20:1 ratio (engine has 5 minutes).

This is a rough guess and it needs to be tested in practice. Such a test would be interesting! If the player has a chance to practice against the engine, then the player will of course be even better prepared for a match. I guess such a preparation is pretty normal for human versus machine matches.

My guess would be that the engine's strength grows faster per additional minute than the human strength per additional 20 minutes. When the engine has 15 or 20 minutes for the whole game, it might already be difficult for the human player to match its strength, despite having extra time. Yet, a team of grandmasters should cope pretty well (given time odds).
> 8 votes

# Answer
Yes, at some ratio. But that ratio changes every day, in favor of the computer. Grandmasters are getting very slightly better over the years, while computers double in speed every few years. Maybe a GM could win with 100:1 time odds today, but they would need 1000:1 soon, and 10000:1 soon thereafter.
> 3 votes

# Answer
Your question is stated in such a way, that the answer **Yes** is almost certain. And I will explain why.

First of all, from mathematical (game theory) point of view, chess is an extensive-form game, which means that it has a Nash equilibrium. Taken these hard words away, this means that from a theoretical point of view, with a perfect game if a game is not a draw, than one of the players have a sure win (think about it as a forced sequence of X moves from starting position to win). So here is where certainty in my first sentence comes from. If computers will be all-powerful, no matter how small the gap will be, they will be able to draw the match (thus grandmasters would not be able to win with any gap).

This was theoretical, but with a current situation, one can always find time-odds to be able to win. For example even I would be able to win the best machine with the following timing: me 240 minutes - machine 10 seconds (try it by yourself). Note, that Sparr correctly stated that ratio will be increased every day, till may it will come to my theoretical conclusion stated in paragraph 1.

Note, that Rauans' answer does not take into account one important thing - computer is not sitting and doing nothing while you are thinking! The engine evaluates all possible positions during that time as well. So you can not really sit and wait for a lot of time, thinking that you will overwhelm the machine with your strange move.

Another important addition is to see the progress of machines and the progress of humans. Take Carlsen Magnus (the strongest human) and check his progress: from Jan 2011 to Mar 2014 he reached from **2814** to **2881**. So **67 points in more than 2 years**.

Take Houdini from its 1.5a release in Jan 11 to current 4 release it gained from **3200** to **3313** points. So during the same time **113 points** (and you know that the higher you stand, the harder to get additional points). Also it was not running on supercomputer (but rather on an average machine : Athlon 64 X2 4600+ (2.4 GHz)). Also note that chess logic is easy to parallel and check current speed of some of the most powerful distributed hashing network running on specific dedicated hardware: 30 Peta hashes per second (30 million Gh/s)

I also advice not to listen to Fischer's comments, because Elo define a probability of winning and based on the history, it shows pretty nicely who is stronger then who on a high level. So this is not really such a stupid number.

Computers are better than us not only in middle game, they have all opening repertuar (some openings goes far than 17 moves in depths) and can include also vast amount of precalculated theoretical novelties, which non of the humans can remember, also they have all up to 7 pieces endgames (and even for a good GM it is not as easy to win queen+king vs rook+king.

No computer can be better than capablanca|fisher|kasparov? A game in 1996 showed otherwise, and this is ancient age in terms of computers (note that currently even PC on mobile phone HTC in the example is better/on the same level as Carlsen)
> 3 votes

# Answer
**Nope**

Time odds are irrelevant on the computational side. Computation of chess positions is easily parallelized, meaning additional computational resources can be brought to bear independently of time constraints. The linear component of the processing will be trivially small compared to the time controls.
> 2 votes

# Answer
Absolutely not, a human has no chance whatsoever to win against supercomputers these days, even at 10 to 1 ratio on time. Chess engines on supercomputers are so sophisticated these days that they can calculate up to 200 million moves per second, versus a human's ability to calculate 2 moves per second at most. Besides, the computer -- just like a human -- doesn’t wait for the opponent to make his move to start thinking; it is constantly weighing all the options even before the opponent makes its move. So I think the time ratio is irrelevant in this case.
> 2 votes

# Answer
I'd like to address a slightly different question: would a grandmaster be ***favored*** to win over a computer given time odds? I say this because even a weak player has some statistically significant probability of beating a world champion eventually, even if it took the rest of time. The answer to my modified question, I believe the **answer is no**.

Programs and people evaluate their opponents moves in different fashion. People can be surprised by their opponents moves, and need time to rethink the consequences. However, a computer, if left to ponder a position during its opponent's move, has already considered all meaningful replies up to its search horizon. In the limit, you essentially cut its ponder time in half, if it immediately makes its move, and only thinks on its opponents time. Now the difference in time to calculate one ply (one half move) deeper means about a 40 fold increase in processing time (the search tree grows exponentially by the branching factor, which is ~40 new moves). The additional lost time wouldn't even be able to search a single move deeper! You essentially gain **1 ply** because the computer must search all your possible replies rather than the one you eventually make.

So how much is that one ply of additional search worth to the computer? In the 1980s, when search depth was small, experiments showed a program searching at a depth of 6 was 159 elo points better than one searching at a depth of 5. Later research in self play experiments went on to show that as seach depth increased, there was a diminishing return in elo gain... a single ply increase from a depth of 11 to 12 resulted in an elo gain of 84 points. Note this research is about 16 years old. Note the ratings gap between Stockfish and Magnus Carlsen is already around 450 points. Almost counter intuitively, it would seem reducing the time control could give humans the best advantage (unfortunately, assuming a human's rating doesn't also drastically decrease with less time).

I could see two possible factors that would make me change my mind.

1. If diminishing returns were only a property of computers, and not humans (or the rate of change was significantly different). Suppose you matched a computer against a postal player. Perhaps the strategic decisions a human is capable, given enough time, outweigh the computer's tactical abilities. Then, with enough time, a human could potentially be favored.
2. If the time odds exponentially changed per move. Give the human 1 second on the first move, one minute on the next, one hour on the following... etc etc, we could effectively force a computer to be at a perpetually greater disadvantage than 50% time odds. If the human capacity for discovering improvements truely could scale to those limits, then a computer would eventually be overwhelmed by the time advantage.

However, my final analysis puts my two caviots as unlikely scenarios, and I believe that with any time odds, **a computer would likely be the favorite**.
> 2 votes

# Answer
With sufficient hardware and parallel processing, it would be possible to process the positions from all of the human's possible replies, in his time, then use the results immediately for his chosen move. So through programming and hardware, it would be possible to overcome virtually any time odds.
> 0 votes

# Answer
Sorry to state the obvious but you do realise human engineers designed the computers and human programmers and chess experts wrote the programs.when a computer writes and designs a chess program that it cannot itself defeat then the machine awakes!
> -3 votes

---
Tags: engines, grandmaster, human-versus-machine, handicapping, time-control
---


# Question
Title: Bizarre pin rule: pinned pieces do not attack
I found this guy who likes playing chess, but not enough to bother reading the rules; he only plays using a physical board with his sister (she doesn't know the rules either).

The made up rule was this:

> A pinned piece is *not* attacking the squares he can't reach the next move without exposing the king.

Which means, a lot of things can happen:

* A king can move to an 'attacked' square if the piece is pinned.
* By removing the pin, the piece now attacks the squares he wasn't (this can result in discovered checks if the king was in one of these squares).
* You can remove a check by pinning the attacking piece.

If you think about it, it requires much more thinking process to play like this. I was at a disadvantage because it is really hard to see these new threats and tactics if you never played like this before.

My questions:

* Does anyone know if this is some kind of known chess variant?
* Should I tell them the correct rules even when I know they are not that serious about playing?
* Are these rules more complex to understand than the official pin rules?

# Answer
Well, it's a variant (since it's played by your friend and his sister, and probably at least some others), but not a well-known one. I used to think this idea would be only logical until I realized that a King moving into a square attacked by a pinned piece could still be captured by the pinned piece, and even though the opposing King would then be exposed to attack, the first side would already have lost. Note that though Black leaves himself in check with his move, he still wins because he theoretically captures the King first:

```
[FEN "8/8/5k2/4r3/8/2B5/8/5K2 w - - 0 1"]

1.Ke1 Rxe1 2.Bxf6

```

Compare with a position in which it's a mate in one for whichever side moves first. Say White checkmates, then Black has lost *even though he can checkmate in one move*. This is due to the same reason that Black won in the previous diagram. Theoretically, White wins because he can capture the opposing King first:

```
[FEN "6k1/5ppp/6r1/8/8/1R6/PPP5/1K6 w - - 0 1"]

1.Rb8# Rg1# 2. Rxg8 Rxb1

```

To your second question, I see no reason why you should not let them know the real rules. You are the best judge of whether he'd be open to learning them. Don't be overbearing and certainly be willing to play his variant if he obviously doesn't care for the standard rules. Games are for fun.

And to the extent that it requires consideration of more possibilities, it *is* more complex tactically.
> 18 votes

# Answer
This post is in response to RemcoGerlich's request for a source for Annunuki's claim that the rule discussed here is an old rule.

From *A History of Chess* by H. J. R. Murray, chapter 5, "Chess in the Malay Lands", page 103:

"This leads to a still greater anomaly, a piece which is covering a check is deemed to have no power of giving check to the opposing King: e.g. White, Kg5, Bg4; Black, Ke2, Rf3, Pd3; White can calmly play Kf4 and draw the game."

The surrounding text offers no additional insight. In the above example, I do not see the draw, but this is part of a section that discusses chess as played by the Bataks, and likely involves other rules that differ from modern chess. Nonetheless, the reference seems relevant.

Source: Murray, H. J. R. A History of Chess (Northampton, MA: Benjamin Press, 1985)

As an aside, Murray's 900 page book from 1913, long out of print, was reprinted last year by Skyhorse Publishing for a reasonable price.
> 14 votes

# Answer
### Answers

* It sure **is a chess variant**, and now that you brought it up, it just became of the *known* kind. I take good note of it, even though I never heard of it before. It does sound illogical, as Daniel's comment highlight, so I don't think regular players would come up with it.
* Tell them or not : *does it really matter ?* Don't be authoritative about the standard ruleset, that would be pointless. If you can see a way to lightly mention the official rules, do it, maybe they care, but if they don't, that's it.
* These rules are illogical once one understands it's all about capturing the king, as Daniel very well points out. **Yes, they are more complex to understand.**

---

## Strange things happening

Here's a position where I think this ruleset allows strange things to happen :

```
[FEN "8/8/2Rr1k2/4n3/3B4/3K4/8/8 b - - 0 0"]

1... Nxc6 {Is moving an actually pinned piece out of it's pinning direction legal ?}

```

Here, the white rook pins the black one, so the bishop is not pinned, but the knight is. Altogether, white pins black. Black to play, capturing the rook would lead to a legal position, because it indirectly pins the bishop, *a posteriori* freeing the knight, for there is no check from the just-pinned bishop. I argue this being a legal move is dubious, for the knight **is** pinned, for the time being.

It could be in this ruleset, but I found that to make these rules highly paradoxical. Somehow, you shouldn't be able to get a pinned piece out of its pinning direction — even if later on, it comes back on the board to legitimate it had the right to go away. I feel there's a “meantime” in which the position isn't legal, hence the move shouldn't be.

Let's develop on that “delay” thing :

```
[FEN "8/3rPK2/2k5/8/8/8/8/8 w - - 0 1"]

1. e8=P {what now ?} (1. e8=B {legal}) (1. e8=R {promoting to a non-bishop-behaving piece is illegal})

```

If the newborn consensus is right — a move ending up with a legal position is legal — then this promotion can only be made to a bishop-behaving piece. Again, I'm not liking the time during which the pawn lets the king vulnerable, but I'm more and more convincing myself that that's just my pinning intuition getting in the way.
> 11 votes

# Answer
To answer the subquestion: "Does anyone know if this is some kind of known chess variant?"

Yes, it is a known chess variant. It goes under several names including PMDNC (Pinned Men Do Not Check), Pin chess, Superpin, or Stevens Principle. Its written history dates back at least to a publication by SJ Stevens in Westminster Papers in 1875.
> 11 votes

---
Tags: rules, chess-variants, pins
---


# Question
Title: What is the best opening that i should learn
What is the best opening that i should learn , And how much time should be spent on learning an opening?

# Answer
If you're a beginner in chess I advise you to start off with opening that help develop your chess as they can evolve into multiple type of positions (90% of the time I advise beginners to start off with the Italian Game/Italian Opening).

If you're playing as black however, something like the French Defense would be advised... The Sicilian is too advanced for a beginner to learn cause most likely you won't be able to understand everything that is going on even if you know the lines of the Sicilian.

According to your comment, you like Queen's Gambit and the Ruy Lopez... Surprisingly enough both have very different play styles, Ruy Lopez being extremely offensive type of opening while the Queen's Gambit more tactical. However if you truly want to stick with either of those openings I suggest you stick to Ruy Lopez as it is not as complex as Queen's Gambit.

Here are other openings you might want to check out: Ponziani Opening, Scandinavian Defense(although I don't advise it since it breaks one of chess' principles, which is : don't bring the queen too early in the game).

However if you're more advanced you can go ahead and explore the Sicilian, King's Gambit, Queen's Gambit and King's Indian.

How much time you should spend on studying openings? **Minimal**... Openings are mostly a memorized sequence of moves which you understand better as you reach higher levels in chess, with somewhat solid knowledge of some openings you will won't have issues starting a game... But the moment you go into the middle game or if your opponent doesn't play according to the book (basically doesn't follow the normal lines of an opening) then your opening knowledge will help you very little in here, if not at all.

Most of your time in chess should be devoted to middle game and end game (the latter requiring most of your time as it is the hardest to master).

If you have any questions feel free to comment and I'll answer to the best of my abilities.
> 2 votes

---
Tags: opening
---