Why is the Cozio defense in the Ruy Lopez not played more often and what's white's best try to defeat it? The Cozio defense arises after these moves:

[FEN ""]

1.e4 e5 2.Nf3 Nc6 3.Bb5 Nge7

At first, this looks like just another dubious opening, but I found it surprisingly hard to prove an advantage with white.

[FEN ""]

1. e4 e5 2. Nf3 Nc6 3. Bb5 Nge7 4. O-O g6 5. c3 Bg7 6. d4 exd4 7. cxd4 d5 8. exd5 Nxd5 9. Re1+ Be6 10. Bg5 Qd6 11. Nbd2 O-O

It is not clear how white should proceed. There are many options, but black has several different ideas and can quite easily general counter-play. Going 12. Ne4 Qb4 13.Bxc6 bxc6 seems like the most principled approach, but black is just fine in these lines. He can drum up quite interesting play judging from the grandmaster games I looked at. This line:

[FEN ""]

1. e4 e5 2. Nf3 Nc6 3. Bb5 Nge7 4. Nc3 g6 5. d4 exd4 6. Nd5 Bg7 7. Bg5 h6 8. Bf6 Bxf6 9. Nxf6+ Kf8 10. O-O

is given by some FIDE-Master on YouTube, but I'm also not very convinced. I just fail to see white's advantage in this position. So, I have two questions:

Why is the Cozio defense played so rarely?
What is, in your opinion, the best way to secure an advantage against it as white?

The major reason is that it is played so rarely is that if white does not comply and take on c6, the Ne7 is poorly placed blocking the Bf8, and if the knight goes to g6, that just does not look like a good square either. In addition, it does not really help get in d5 since white gets there first with d4, or it just loses a pawn. Since that is not possible, the Bf8 must go to g7 where it just seems out of place with what most Spanish players are used to, and prefer. Also, most of the lines are still slightly better for white, even if they are subtle in nature.

There are three moves that are played on move four with a very high frequency: 0-0, c3, and Nc3. Nc3 seems like the best to me since it thinks very prophylactically, and stops d5 for a long time. In addition, the winning percentages for each move are 53.1%, 56.8%, and 62.6% respectively pre the Mega 2020 database.

I tend to like double e-pawn positions that white has more space because black has a d6 pawn. You can then eventually post the Nc3 on d5, cramping black further. I am going to propose that you play 4.Nc3, and aim for such a position since the plans for white are aggressive, and clear. In addition, I like positions with more space, in general, since I think that it makes it harder on your opponent in a practical game.

Despite my recommendation, I am going to add in some of the other lines so you can look at them, and decide if you prefer any of them. The other lines are also quite good, but they are also much more nuanced, and require very patient, and precise, positional play, compared to the main 4.Nc3 line I am proposing, which involves either a direct attack, or bringing the rooks to the center, and slowly advancing the kingside pawns.

 [FEN ""]

 1. e4 e5 2. Nf3 Nc6 3. Bb5 Nge7 4. Nc3 (4. c3 g6 5. d4 exd4 6. cxd4 d5 7. exd5 Nxd5 8. O-O Bg7 9. Re1+ Be6 10. Bg5 Qd6 {Transposes to 4.0-0.}) (4. O-O g6 5. c3 Bg7 6. d4 exd4 7. cxd4 d5 8. exd5 Nxd5 9. Re1+ Be6 10. Bg5 Qd6 11. Nbd2 O-O 12. Ne4 Qb4 13. Bxc6 bxc6 14. Qc1 Rfe8 15. Bd2 Qb6 16. Nc5 Bf5 17. b3 {With a very positional game revolving around the control of c5.}) 4... g6 (4... d5 $4 5. exd5 Nxd5 6. Nxe5 Nxc3 7. dxc3 Qxd1+ 8. Kxd1 $16) 5. d4 exd4 6. Nxd4 (6. Nd5 {Another main line.} Bg7 (6... Nxd5 $2 7. exd5 Qe7+ 8. Kf1 Ne5 (8... Qb4 $2 9. Qe2+ Ne7 10. Bg5 Bg7 $2 11. Re1 $18) 9. Qxd4 Bg7 10. Bf4 f6 11. Re1 $16) 7. Bg5 h6 8. Bf6 Bxf6 (8... Kf8 9. Bxg7+ Kxg7 10. Bxc6 Nxc6 11. Nxd4 $16) 9. Nxf6+ Kf8 10. Qd2 $14) 6... Bg7 7. Nxc6 $5 (7. Be3 O-O 8. Qd2 d5 9. O-O-O dxe4 10. Bxc6 Nxc6 11. Nxc6 Qxd2+ 12. Bxd2 bxc6 13. Nxe4 Bf5 14. Rhe1 Rfe8 15. Ng3 Be6 16. b3 $14) 7... Nxc6 8. Be3 O-O 9. Qd2 d6 10. O-O-O $14


How can chess be applied to other fields like politics or football tactics? I just think that a strategy game such as chess can be applied to the real world and in that chess can make you a better strategical person, but how so?

Here are some example areas I think can of (definitely not limited to just these):

Attacking your opponent at different parts of the board simultaneously. This can be translated to pressuring your real world opponent in different ways at the same time.
Identifying weaknesses.
A sense of danger. I don't know how well this would translate into the real world, but in chess you develop an intuition for what's really a danger and what's not.
Calculation skills, both for thinking far ahead (depth) and considering a number of options your opponent could go for (breadth). This has obvious applications when trying to figure out what your opponent will do in politics, football, etc.
Distributing and maximizing resources. In chess you need to figure out where to put your pieces, based on where they are most needed/can be most effective.

However, correlation doesn't necessarily imply causation. Getting good at chess might have given someone these real world skills; or, they could already have these skills and that's why they're good in both chess and certain real world activities. A likely possibility is that someone is already fairly strategical, and then playing chess amplifies their abilities.


The Black knight challenge [FEN "8/8/8/8/8/pNnbPPpN/RBppPbrP/pkKPrqQR b - - 0 1"]

I was introduced to a challenge a few weeks ago with the above position. The challenge is to move the Black Knight such that it must always be three squares in the third row from the right, the point is to capture all pieces with the Black Knight. The order of the other pieces doesn't matter.
While an answer is awesome, what I'm mainly interested in is, is this really a thing?

As @Glorfindel pointed out, this is a knight's tour.
One sequence is Nc3-a2-c1-b3-a1-c2-a3-b1-d2-f3-h2-f1-e3-g2-e1-d3-b2-d1-f2-h3-g1-e2-g3-h1.
[FEN "8/8/8/8/8/pNnbPPpN/RBppPbrP/pkKPrqQR b - - 0 1"]

1... Nxa2 2. null Nxc1 3. null Nxb3 4. null Nxa1 5. null Nxc2 6. null Nxa3 7. null Nxb1 8. null Nxd2 9. null Nxf3 10. null Nxh2 11. null Nxf1 12. null Nxe3 13. null Nxg2 14. null Nxe1 15. null Nxd3 16. null Nxb2 17. null Nxd1 18. null Nxf2 19. null Nxh3 20. null Nxg1 21. null Nxe2 22. null Nxg3 23. null Nxh1

How did I create the sequence? I used Warnsdorff’s Rule:

Always move to an adjacent, unvisited square with minimal degree.

Where the degree is:

the number of unvisited squares that are adjacent to a given square

In the case of ties, I calculated ahead and made sure that the knight didn't get stuck.


What is the fifth position in the KN vs. KR endgame with the knight mating? I can come up with 8 positions where the knight would deliver checkmate to a rook and king. However, on endgame tablebases, there are only 5 positions where a King knight wins against King rook. Why?

The positions are not unique if they are in some way symmetrical.
The five positions where KN wins vs. KR are:

White to play:  White Kc1 Nd2, Black Ka1 Ra2
White to play:  White Kc1 Nd4, Black Ka1 Ra2
White to play:  White Kc1 Nc5, Black Ka1 Ra2
White to play:  White Kc1 Na5, Black Ka1 Ra2
Finished game:  White Kc1 Nb3, Black Ka1 Ra2


Is it legal to hit the clock with piece, captured or otherwise? I have often seen in blitz games that when a player captures a piece and then hits the clock with the piece. Is that a legal move or is the player required to place it on the table and hit the clock with the hand?

Similarly, in the case of promotion, can a player hit the clock with the pawn after it is removed from the board after a promotion.

I also have seen players hold a piece in their hand during play, typically awaiting a promotion (with queen in hand) or just holding a piece?

Are there any official rules that govern hitting the clock with a piece or even holding a non playing piece during play?

Update: I know it is a bit late, but I the ultimate reason for asking relates to classic chess clocks where the buttons are somewhat small and stiff where pressing the buttons multiple times with your hand, especially in blitz games can get quite painful.
More recent clocks have bigger and softer buttons so it is not really an issue if using one of those.
This is where hitting the button with a piece is much easier on the hand. Does this have any affect on the final answer?

I feel this is legal. I'm using FIDE rules.

This is the rule that describes what happens with a capture:

  3.1.1 If a piece moves to a square occupied by an opponent’s piece the latter is captured and removed from the chessboard as part of the same move.

There's nothing there about what happens to the captured pieces, other than they are removed from the board.

Now, of course somebody will argue that this rule exists:

  6.2.3 A player must press his clock with the same hand with which he made his move. It is forbidden for a player to keep his finger on the clock or to ‘hover’ over it.

And there it says "with the same hand". But you also have to remove the captured piece with that hand, and once you've done that you have to press the clock, and there is no requirement to let go of the piece. I argue that this rule is intended to be used against people who move a piece with one hand and press the clock with the other, not against using the piece that you happen to have in your hand.

Of course, there is an opportunity for bad behaviour, by hiding pieces in your hand so that the opponent doesn't notice he is behind in material (IMO that's that opponent's fault, look at the board not at the removed pieces), or worse, hiding the piece that the opponent wants to promote to. Or by simple distracting the opponent by constant fiddling with pieces in your hands.

But there are already rules against distracting the opponent, there is also the umbrella rule against "bringing the game of chess into disrepute", and when you want to promote but don't immediately spot the piece it is always acceptable to stop the clock, call an arbiter and have him fetch the piece for you. That is enough ammo to use against bad behaviour.


Between chess and music Among the world champions, at least Capablanca and Tal have suggested that chessplayers sit closer to musicians than logicians.

Mark Taimanov, WC contender in 1971, was a world-class concert pianist.

Here is a duet he played in 1957.

One more. I don't know when it was played. This one shows he and his partner playing.


Why do some openings have Indian in their name? Why are a few chess openings named King's Indian Defense, Queen's Indian Defense, Nimzo-Indian defense, and so on?

What is the significance of Indian in all these opening names? What's India's contribution to it?

In Indian Chess, the game that was played in the 18th, 19th and early 20th centuries in India (not to be confused with its ancestor Chaturanga), the rules allowed no castle, but :

The king can make a knight's move once in a game, known as Indian castling.

As a consequence, g3 followed by Kg2 for White or ...b6 followed by ...Kb7 (the black king stands on d8 at the beginning of the game in Indian chess) were very common moves in the opening, since it was the fastest way to bring the king towards the corner where it will usually find the most safety.
Of course, playing g3, b3 or ...b6, ...g6 could also be followed by a "normal" fianchetto with the camel (our bishop).
When Indian players started playing western chess (during colonization), they quite naturally used a lot of fianchettoes, since they are common in Indian Chess. As explained in user1583209's answer, that was the case for Moheschunder Bannerjee in his games against Cochrane around 1850, and The Chess Player's Chronicle used the term "Indian defense" to refer to 1.e4 d6 2.d4 g6 after him, about 30 years later though (1884). This is the first documented use of the appelation about that kind of defense with fianchetto - although "Indian Opening" appeared earlier to refer to 1.e4 e5 2.d3.
The term "Indian Defense" as we understand it today (After 1.d4 Nf6, thus excluding Pirc-Ufimsev and other schemes with e4 and not c4 for White) established itself after WWI, its use being popularized by Savielly Tartakower and Hans Kmoch.


In Fischer-Petrosian 1971 game 7, why did Fischer give up his good knight for a bad bishop? Fischer played 22. Nxd7, which seems strange since the knight looked very good. Why did he play it?

 [Title "Fischer-Petrosian, Buenos Aires (7) 1971, 10/19/1971"]
 [FEN ""]
 [startply "42"]

  1. e4 c5 2. Nf3 e6 3. d4 cxd4 4. Nxd4 a6 5. Bd3 Nc6 6. Nxc6 bxc6 7. O-O d5 8. c4 Nf6 9. cxd5 cxd5 10. exd5 exd5 11. Nc3 Be7 12. Qa4+ Qd7 13. Re1 Qxa4 14. Nxa4 Be6 15. Be3 O-O 16. Bc5 Rfe8 17. Bxe7 Rxe7 18. b4 Kf8 19. Nc5 Bc8 20. f3 Rea7 21. Re5 Bd7 22. Nxd7+ Rxd7 23. Rc1 Rd6 24. Rc7 Nd7 25. Re2 g6 26. Kf2 h5 27. f4 h4 28. Kf3 f5 29. Ke3 d4+ 30. Kd2 Nb6 31. Ree7 Nd5 32. Rf7+ Ke8 33. Rb7 Nxf4 34. Bc4 1-0

This is a very famous position. Well, here are some reasons, and there are quite a few:

Since this was a Candidate’s Match to qualify to play Spassky, it comes down to exact calculation above all. Fischer calculated that it was good, and his judgement bore out since the game only lasted another 12 moves. Here are some things that probably contributed to this judgement.
It was clear that black had to take with the Ra7 so as not to lose d5, and after that, neither black rook remains well placed since the Ra8 cannot leave the Pa6 undefended, and either the Rd7 or the Nf6 is stuck defending d5. D5 also limits the scope of the Rd7, in particular.
It also leaves the Pa6 particularly weak since the Bd7 might have been able to defend it. GM Mikhail Suba is famous for saying "Bad bishops defend good pawns!" In addition, when you look at the minor pieces that are left, the Bd3 versus the Nf6 is clearly in favor of the B and its nice scope. It is of note that if black tries to liquidate the Pa6 weakness with a5, white can just push, creating a dangerous passer.
Lastly, and most importantly in this position, the white Ra1 immediately takes the only useful file, the c-file, with an immediate threat of Rc6, thus black played Rd6 stopping it, which allowed white to take the 7th rank.
In all fairness, the computer finds both 22.a4 and 22.Rc1 stronger by about half a pawn, but Fischer’s method is clear, and very straightforward.


Have we found every existing tactic? Is it possible that there are missing or unstudied tactics, waiting there to be found?

Maybe some of them have been played only by GMs and in so few times that they don't get to have a name on their own, maybe the rest of the world just see them as 'just another brilliant move'.

What I am saying is, if we were all geniuses and GMs, do you seriously think the number of known tactics would remain the same? Maybe they are so complex that they cannot be learned by books, but by experience.

Or, should I stop watching conspiracy movies?

The type of complex tactic you are thinking of is called a combination. A combination is a forcing series of moves to create some sort of advantage; some would also say that a combination must begin with a material sacrifice, but this is besides the main point. If you are interested in combinations, look at the games of Mikhail Tal, for one, who has been called "the wizard of combinations" for his daring, speculative sacrifices which often led to his opponent cracking under the pressure of searching out the one saving defensive resource; or Alekhine, "the genius of combinations", whose combinations, if not as daring as Tal's, were perhaps more sound.

Wikipedia gives the following example of a combination:

r1b2r2/p2p2kp/1pn1p3/8/1PP5/P2K1P2/2Q4P/R4B2 b - - 0 1

1... Rxf3+ 2. Ke4 (2. Ke2 Nd4+) (2. Kd2 Rf2+ 3. Be2 Rxe2+! Kxe2 Nd4+) d5+!! 3. cxd5 (3. Kxf3 Nd4+)  exd5+ 4. Kxd5 (4. Kxf3 Nd4+) Be6+ 5. Kd6 (5. Kxe6 Nd4+) (5. Kxc6 Rc8+) (5. Ke4 Bf5+) Rd8+ 6. Kc7 (6. Kxe6 Nd4+) (6. Kxc6 Rc8+) Rf7+ 7. Kxc6 Rc8+

In light of the impending disaster, White in fact resigned on move 3 (Move 22 in the actual game between G. Stepanov and Peter Romanovsky).


Analysis of chess by Philidor in PGN Where can I find games annotated by Philidor in his book in    a PGN file?

You can find Philidor’s 1790 book here in a free Google Books scanned eBook of it.


Unable To Communicate with UCI through Java Program I am writing a java program to connect to the Stockfish Engine and get the best move for some FENs.
My Connection code is :
public class connector {
    private Process engineProcess;
    private BufferedReader processReader;
    private OutputStreamWriter processWriter;
    private static final String Path = "path\to\stockfish.exe";

    public boolean startEngine() {
        try {
            engineProcess = Runtime.getRuntime().exec(Path);
            processReader = new BufferedReader(new InputStreamReader(
                    engineProcess.getInputStream()));
            processWriter = new OutputStreamWriter(
                    engineProcess.getOutputStream());
        } catch (Exception e) {
            return false;
        }
        return true;
    }

    public void sendCommand(String command) {
        try {
            processWriter.write(command + "\n");
            processWriter.flush();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    public String getBestMove(String fen, int waitTime) throws IOException, InterruptedException {

        sendCommand("position fen " + fen);
        sendCommand("go movetime " + waitTime);
        return getOutput(waitTime + 20).split("bestmove ")[1].split(" ")[0];
    }

    public String getOutput(int waitTime) throws IOException, InterruptedException {
        StringBuffer buffer = new StringBuffer();

        try {
            Thread.sleep(waitTime);
            sendCommand("isready");
            while (true) {
           String text = processReader.readLine();
           System.out.println("Text is " + text);
           if(text.equals("readyok"))
              break;
           else
              buffer.append(text + "\n");

          }
          catch (Exception e) { e.printStackTrace(); }

        return buffer.toString();
    }

    public void stopEngine() {
        try {
            sendCommand("quit");
            processReader.close();
            processWriter.close();
        } catch (IOException e) {
        }
    }

}

My Driver Code is as Follows :
connector con = new connector();
        boolean started = con.startEngine();
        if(started) {
            Thread.sleep(1000);
            String bestMove = con.getBestMove("1nbqkbnr/1ppppppp/p7/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1", 5000);

            System.out.println(bestMove);
        }else {
            System.out.println("Failed To Start Engine");
            System.exit(0);
        }

The Output I am getting is :
java.lang.ArrayIndexOutOfBoundsException: Index 1 out of bounds for length 1
at connectors.connector.getBestMove(connector.java:42)

I am having a hard time understanding what is wrong with my code. I understand that using processReader , I am reading the InputStream of the engine and appending it to String "text" until I encounter "readyok" , and finally returning this string. But when I output this , it gives me everything including info like
info depth 1 seldepth 1 multipv 1 score cp 539 nodes 83 nps 41500 tbhits 0 time 2 pv e5f6 info depth 2 seldepth 2 multipv 1 score cp 790 nodes 182 nps 91000 tbhits 0 time 2 pv e4d5 b7b6 e5f6
I am unable to get the Best Move. How can I do this?

info depth 1 seldepth 1 multipv 1 score cp 539 nodes 83 nps 41500 tbhits 0 time 2 pv e5f6 info depth 2 seldepth 2 multipv 1 score cp 790 nodes 182 nps 91000 tbhits 0 time 2 pv e4d5 b7b6 e5f6
obviously doesn't have any best move in it. Stockfish needs time to give you a move. Your program will need to filter out those principal variation lines.
Please don't use waitTime.  Did you ask for 20 seconds? Chess engine may not stop the search exactly after 20s. Do something like this:

Wait from Stockfish in real-time. In C++, it's something like read() (can't remember exactly without a Google search). Your worker thread waits for the next Stockfish output.
Check if "bestmove" is in the line, if not, do nothing

Pseudocode looks like:
f = ... // handler to Stockfish's standard output
while (true) {
    line = f.read() // Read Stockfish's next line. Blocked if nothing.
    if ("bestmove" in line) { // Best move?
        ... parse the move ...
    } else {
        print("Do nothing!")
    }
}


Easy variation to learn with White against Semislav with not many lines and avoiding the Slav at the same time if possible I'm looking for an easy variation to learn against the Semislav. Note that I play d4, c4, Nc3 against many openings. I tried to play the 5.Bg5 line but I felt that it was full of memorization:
[FEN ""]
1.d4 d5 2.c4 c6 3.Nc3 Nf6 4.Nf3 e6 5.Bg5

So I switched to playing the Bogolyubov line which avoids the Slav dxc4 because my Bishop can take it with temp:
[FEN ""]
1.d4 d5 2.c4 c6 3.e3 Nf6 (3...Bf5 4.Nf3 e6 5.Be2 Nf6 6.O-O) (3...e6 4.Nc3 Bb4 (4...f5)) 4.Nc3 e6 (4...g6)(4...Nbd7)(4...a6)(4...Bf5) 5.Nf3 Be7 (5...Nbd7)(5...Bd6)(5...dxc4) 6. Bd3 Nbd7 (6...O-O) (6...dxc4) 7. O-O O-O

Btw, I tried playing the slav with white before switching to the Bogolyubov line as
[FEN ""]
1.d4 d5 2.c4 c6 3.Nc3 Nf6 4.Nf3 dxc4 5.a4

But I didn't like them that much. Maybe because I haven't read about them a lot. As you can see, there are tons of variations in the Bogolyubov line, including the Meran. It's too much! I would really appreciate it if somebody can give me either an easy line against the Semislav that avoids the Slav, or two easy lines against Semislav and slav.

The easiest to learn is the exchange variation.  It leads to the persistent opening advantage, but doesn't offer much opportunity for a crushing win.  This is the line I played when I had to face the Slav.

[FEN ""]

[White "?"]
[Black "?"]

1. d4 d5 2. c4 c6 3. cxd5 cxd5 4. Nc3 Nc6 5. Nf3 Nf6 6. Bf4 Bf5 (6... a6 7. Ne5)
7. e3 e6 8. Bb5 Rc8 9. Qa4 Nd7 10. Bxc6 Rxc6 11. Qxa7 Qc8 12. Qa5 Ra6 13. Qc7
Qa8 14. O-O Bd3 (14... Rc6 15. Nb5) 15. Rfc1 Rc6 16. Nxd5 exd5 17. Rxc6 bxc6 18.
Ne5 Nxe5 19. Qxe5+ Be7 (19... Kd7 20. Qc7+ Ke8 21. Rc1) *


What Sicilian Defence variation has the most similarity to the Dutch? Given that in GM Simon William's book The Killer Dutch, Williams says that the Sicilian and the Dutch are mirror images of each other, as Williams states "If you look at the first move, you can see that the two openings are similar, due to the fact the initial pawn structures of both openings are actually mirror images of each other." (Williams, 32) What Sicilian Defence variation has the most similarity to the Dutch? In the sense of pawn structures, middlegame plans, and strategic ideas? From what I observe it seems to me like the Scheveningen is similar to the classical variation of the Dutch.

Which variation do you think is most similar?

"If you look at the first move, you can see that the two openings are similar, due to the fact the initial pawn structures of both openings are actually mirror images of each other."
That's one of the most patzerish things I've ever read in a book written by a strong player.
Flip the board around, and I don't think anyone (not even Simon Williams) would suggest the English and the Bird are similar, except that all four (Bird, English, Dutch, Sicilian) of them influence the center from the wing instead of through direct occupation, and none of them do as much for one's development as a central pawn move.


What is the opening value of 1. e4 in 2020? Bobby Fischer:

  e4 -- best by test.

What is the current theory or trend in theory behind this statement?

We have seen huge strides taken in chess AI in the past two years. How is this affecting opening theory regarding the "best first move"?

It's still one of the best moves White can play. There's no clear consensus on whether 1.e4 or 1.d4 is better, but it's played frequently at the top level. Due to advancements in theory, I'd say 1.e4 isn't regarded quite as highly as it was in the past, but again it's most likely White's best/second best move.

Advancements in AI aren't really affecting theory on the first move. Games from AlphaZero/Leela are good for new ways of thinking in the middlegame or late opening, but they're not changing our fundamental opening understanding.

EDIT - also, technically 1.e4 isn't "best by test" currently. In my database it scores 52.8%, while 1.d4 scores 54.4%. But to be fair, 1.e4 has been played in roughly 1.5 million more games, and the types of players who favour 1.e4/1.d4 may differ.


Why was the founder of chess killed? I have heard from many a story in which a man who introduced the game of chess was hanged or killed by his king. What was the actual story and the the reason for killing the founder of chess?

The exact origins of chess are not known, but there are several stories about it out there. At the top of my head I can think of at least four different ones that I've heard myself, and after reading your question I suspect that you've heard of one such story about the creation of chess.

One of these, which may or may not be the story you seem to have learnt about, is the one that follows:

A long time ago, a bored king asked one of his underlings to bring him some form of fresh entertainment. The underling thought for a while, and came up with the game of chess. After playing one game, the king was so pleased with what the underling had brought him that he said that the underling could ask for anything he desired as a reward for the invention of the brilliant game.

After contemplating for a while, the underling asked for a grain of rice for the first square of the chess board, two grains of rice for the second square, four grains for the third square, and so on for the remaining squares. The king agreed to the request, and when it was realized that the total amount of grains the underling had asked for was impossible for the kingdom to provide, the king got angry and ordered the execution of his underling for making a fool out of him.

It is important to note, however, that this story has no proven historical validity whatsoever.


What does it mean when a position is "complicated"? I have watched many of GM Daniel King's videos where he analyzes games. He is always saying "the position is complicated" or "the position is fantastically complicated".

But what does this mean?

If I, eg, put such positions into a chess engine (such as Stockfish) how do I see the complexity factor?  Normally all I see is a simple +.nn number that completely characterizes the best next move.

Well, according to Merriam Webster:

  difficult to analyze, understand, or explain

Unfortunately, you have to trust the GM on this (unless you are a strong player yourself). There is no way of using a chess engine to determine this. What is complicated for a human (positions with a lot of tactics, with a lot of possible capture sequences) might be very easy for a computer, and complicated positions for a computer (strategic battles) might be a lot easier for humans to judge.


Is this endgame position a theoretical win or draw? The following tactics problem comes from ChessTempo, and was taken from a game between Anatoly Karpov and Alexey Kuzmin. It's white's move.

The idea of the problem is to find white's best move from the shown position.

But my question is slightly different: If both players play perfectly from the position shown in the diagram, can white force a win, or can black force a draw?

[FEN "8/3Q2pk/5p1p/5P2/5K1P/p3r3/b2n2P1/8 w - - 0 1"]

I tried using a few chess engines to analyze the position, leaving them running for hours. White gets a very favorable evaluation (about +4 or +5 depending on the engine). I'd normally consider this to be enough for a certain win. But after looking at the computer's best line it seems that after initially winning some material, white's queen just goes round in circles without making any further progress while the black king sits safely behind the wall of pawns.

I guess either the position is a draw, or the computer isn't able to plan far enough ahead to find the winning line. I can't see an easy way for white to win, but I'm no expert and it's possible I've overlooked something.

So what do you think: is it a theoretical win for white or can black escape with a draw?

I think that the position is a theoretical draw.

While Freeman's answer is quite good, but I think he has overlooked that 1. Qxd2 leads to a clearly drawn position because of Black's amazing response 1 ...Rb3!!

[FEN "8/3Q2pk/5p1p/5P2/5K1P/p3r3/b2n2P1/8 w - - 0 1"]

1. Qxd2 Rb3!! 2. Qxa2 Rb2!! 3. Qxa3 Rxg2

Now I don't see any way for White to win. Black has created an impenetrable fortress and white's queen can do nothing.

The 2400+ rated player Alexey Kuzmin missed the move 1... Rb3 in the game, playing instead 1... Re5? which gives a theoretically losing position. All the engines I tried also miss the sequence 1... Rb3 and 2... Rb2 and instead play a losing move.

I suggest that if there is a forced win for White then we must start looking at 1.Kxe3. This move doesn't win as much material as 1. Qxd2, but it leads to a more dynamic position. White can prevent Black from promoting thanks to black's wrong-colored bishop that is unable to protect the a1 square. White can also threaten to advance the g-pawn to attempt to disrupt Black's wall of pawns.

However a computer analysis of 1. Kxd3 seems to show that despite White's material advantage Black can still get a draw.

I'm no expert, so there may be a mistake in my analysis, so please correct me if I'm wrong.


Another problem-Find color of the pieces Please help me to find solution of this next problem by the legendary composer Andrej Kornilow. It appeared in Shakhmatnaya Kompozitsiya 41 issue in 2001 and it was dedicated to A. Lobusow on his 50th birthday.
The colours of the pieces on the diagram is unknown. The diagram can be obtained in a legal game. One needs to find colou of each piece: Black or White.
[FEN "8/8/2NBQPN1/2QQKQQ1/2PPPPN1/2QPKPP1/2NPPPP1/8 w - - 0 1"]

It is easy to find colors of the most pieces:

 1. The kings should not be checkmated by pawns (otherwise what was the previous move?), so the upper ones are White.
 2. The knight on g4 makes a check to either king, so it made the last move.
 3. All other pieces should not give a check to any king, so we must find the colors of them.
 4. There are 12 pawns and 6 queens, so 4 queens were created, and all other pieces are original.
 5. There are 2 White knights on the top, so knight on g4 is Black.

But then one needs to consider different possibilities of the pawn placements, taking into account possible movements. It is hard for me to find a solid approach to it.

I'm going to start from scratch even though the OP posted a partial answer in the question, so I will be covering some familiar ground.

I began to break the problem down by assigning black to the upper king, then making every piece which attacked him black. Since the g4 knight attacks a king, no other piece can be giving check to either king.

[title "White to move"]
[fen "8/8/2nbqPn1/2QqkqQ1/2PpPpn1/2QPKPP1/2NPPPP1/8 w - - 0 0"]

Immediately I see a problem. The d4 and f4 pawns both give check no matter which color they are, so I inverted the colors:

[title "Black to move"]
[fen "8/8/2NBQPN1/2qQKQq1/2ppppN1/2qpkpp1/2npppp1/8 w - - 0 0"]

This time I painted all chessmen white who would otherwise be checking the white king. Now there are two questions: is the g4 knight white or black, and which other pieces are white?

Let's analyze the promotion situation. There are 12 pawns and 6 queens. The game began with 16 pawns and 2 queens, so this establishes that a) 4 pawns became queens, b) no other pawns were captured or promoted, and c) the original queens are still present.

Let's look at captures. There are 25 pieces, and the game began with 32, so there were 7 captures total. What were the captures? Well, there are no rooks. Also Black has no bishops and White only has one. So in total, 2 black rooks and 2 black bishops were captured, and 2 white rooks and one white bishop was captured. This establishes that there was a maximum of 4 "lane-changes" for white pawns and 3 "lane-changes" for black.

Also, in tallying up the promotions, you have hopefully been able to deduce the color of the g4 knight. Since there are two other white knights targeting the white king, and no pawns were promoted to knights, the g4 knight must be black.

The other three pieces whose colors we can ascertain are the c2 knight and the d2 and f2 pawns, which must be black:

[title "White to move"]
[fen "8/8/2NBQPN1/3QKQ2/6n1/4k3/2np1p2/8 w - - 0 0"]

Now back to the pawn capture analysis. Let's see the pawn skeleton:

[title "Pawn skeleton"]
[fen "8/8/5P2/8/2pppp2/3p1pp1/3pppp1/8 w - - 0 0"]

We know the color of only three, though we also know that at least 6 are black (since at least 2 white pawns promoted to queen), and that they got into their current position using 3 captures or fewer. First, look at the a column. Either that black pawn promoted, or it captured twice, leaving one capture left for the other pawns. Since one capture isn't enough to explain the state of the other pawns, Black's a pawn must have promoted. In that case, either White's a pawn must have changed lanes at least once to let Black's pawn by, or Black's a pawn changed lanes. Now, look at b. Either that pawn promoted, or it captured once. If it captured once, then either a black c-pawn promoted or again captured once (since there is at most one c-pawn left). And again, in order for Black's b pawn to promote, either it or White's b pawn must have captured so they could get past each other. So at least two captures are necessary for columns a and b. We have five captures left.

Let's try to eliminate the possibility that Black has 7 pawns and White has 5. Black promoted the a-pawn, so we're working with b through h. Again, since this analysis mandates that b didn't promote, it captured. After this, there are two c pawns, and in the diagram, there's only one c pawn, so one of those pawns must have captured, too. Remember Black only gets three captures, so he has one left. There are no h pawns in the diagram, so the h pawn must have captured. Out of the diagram, then, if Black has 7 pawns, then he has the c pawn, two d pawns, one e pawn, one f pawn, and two g pawns.

[title "Pawn skeleton"]
[fen "8/3pppp1/2pp2p1/8/8/8/PPPPPPPP/8 w - - 0 0"]

Now, White. If White has 5 pawns, then he promoted 3. Since Black cannot have captured with his a pawn, White must have. Now White has two b pawns. In the diagram, there are no b pawns, and Black has the only c pawn, and the 3 d pawns are accounted for, and the two e pawns are accounted for. So either both white b pawns promoted, or else they would have to capture at least 4 times each to find a spot that would make sense of the puzzle position. Even one such b pawn journey would use up more than the rest of White's 4 captures, so this is impossible. White's a and b pawns must have promoted, using up one capture.

[title "Pawn skeleton"]
[fen "8/3pppp1/2pp2p1/8/8/8/2PPPPPP/8 w - - 0 0"]

I am already beginning to seriously doubt this situation. In order not to use captures, either White's h pawn promoted, or the c pawn promoted (after Black's c pawn captured and before the b pawn captured). Either way, White still needs to end up with one d pawn, one e pawn, and three f pawns. Let's try promoting the c pawn. It would use up the rest of the captures (3) to get the g and h pawns to f. Now the pattern can be fulfilled, but there are no captures left for White's f pawn to get around Black's f pawn, which must be on f2.

[title "Pawn skeleton formation"]
[fen "8/pppppppp/8/8/8/8/PPPPPPPP/8 w - - 0 0"]

1. axb3 a5 2. d3 c5 3. b4 c4 4. b5 c3 5. b6 cxd2 6. c4 d5 7. c5 d4 8. c6 a4 9. c7 a3 10. c8=Q a2 11. b4 a1=Q 12. b5 bxc6 13. b7 c5 14. b8=Q c4 15. b6 e5 16. Qa8 f5 17. b7 e4 18. b8=Q f4 19. g3 f3 20. gxf4 g5 21. h3 h5 22. h4 g4 23. hxg5 g3 24. gxf6 hxg4 25. Qd8 g2 26. Qdc8 g3

But promoting the h pawn means we must cross with the c pawn all the way to the f file, using the remaining 3 captures, and leaving none for the f pawn to get around Black's f pawn, or for the g pawn to move over to f. And promoting any other pawns means moving both the c and h pawns, as well as getting around black pawns with the promoting pawn, as well as moving the g pawn over, as well as letting black's f pawn through. In short, White can't make it with 5 pawns in a setup with Black's only viable 7-pawn structure.

Therefore, since Black can't have 8 pawns, and Black can't have 7 pawns, and Black can't have fewer than 6 pawns (since White has at most 6), each side must have 6 pawns.

Now that I've established the number of pawns of each color, I can better analyze the distribution in the final skeleton:

[title "Pawn skeleton"]
[fen "8/8/5p2/8/2pppp2/3p1pp1/3pppp1/8 w - - 0 0"]

There are no a pawns, no b pawns, one c pawn, three d pawns, two e pawns, four f pawns, two g pawns, and no h pawns. Let's simplify this by counting the minimum lane-changes necessary if pawns are all the same color. We can eliminate the a and b pawns, assuming they promote (because otherwise another pawn promotes, and the a or b pawn uses unnecessary captures to move to that other pawn's file). The h pawns must move to f, making four captures, and a c pawn moves to d, for a total of five. Now from experience we also know that the a and b promotions don't come without a price. At least two additional captures are necessary to get them past each other, making 7. You may argue that another pawn could promote, but that would only increase the number of captures, since then the a or b pawn that didn't promote would need to make additional captures to get into the 5x5 square.

So far so good. We're getting in by the skin of our teeth. We have this:

[title "Pawn skeleton"]
[fen "8/2pppppp/8/8/8/8/2PPPPPP/8 w - - 0 0"]

We've used two captures to get the a and b pawns past each other to promote. They could possibly have been both black or both white, so I will leave that ambiguous. Basically we have 5 remaining captures, up to 4 for White and up to 3 for Black. Firstly we know the h pawns have moved to f (or h to g and g to f, but that comes to the same thing), and that a c pawn moves to d. We know the d2 pawn is black, the f2 pawn is black, and the f6 pawn is white. Sounds like the black c pawn moves to d2, so the c4 pawn would be white. So Black's c pawn comes to c3, White's d moves to d3, Black's c captures d2, White's c moves to c4, Black's d moves to d4. That footwork involves only one capture (black).

[title "Pawn skeleton"]
[fen "QQ6/2pppppp/8/8/8/8/2PPPPPP/qqB5 w - - 0 0"]

1. Qc8 c5 2. d3 c4 3. Bd2 c3 4. Qcb8 cxd2 5. c4 d5 6. Qc8 d4

The e2 pawn is presumably white, since otherwise, White's e pawn makes a capture to get out of the way, and we don't have room in our budget for such extravagance. So the e4 pawn should be black. For f, we know that Black has wormed into f2, and White got to f6. This can be attained by Black moving f to f4, White moving f to f3, Black moving g to g3, Black capturing gxf2 (two), White moving h to h4 then capturing twice (over to g5 then to f6), and Black moving h to h4 then making the final capture to g3 (three). It is also possible for White to move g to g3 and then Black capture h3xg2. But maybe this ambiguity can be ironed out later. In any case, the puzzle position has been attained.

[title "Pawn skeleton formation"]
[fen "8/pppppppp/8/8/8/8/PPPPPPPP/8 w - - 0 0"]

1. a4 c5 2. b4 c4 3. bxc5 b5 4. d3 b4 5. axb5 a5 6. b6 a4 7. b7 a3 8. b8=Q a2 9. c6 a1=Q 10. c7 b3 11. c8=Q b2 12. Qa8 b1=Q 13. Qab8 c3 14. Qa8 cxd2 15. c4 d5 16. Qab8 e5 17. Qa8 e4 18. Qab8 d4 19. Qa8 f5 20. Qab8 g5 21. f3 f4 22. Qa8 g4 23. Qab8 g3 24. Qa8 gxf2 25. h4 h5 26. hxg5 h4 27. gxf6 h3 28. g3 hxg2

Playing around with these pawns inspired me to the final breakthrough. The remaining white bishop is the dark-squared one, which means that Black captured the light-squared bishop, and since the capture didn't occur on the bishop's home square, then the bishop must have gotten out somehow. The e pawn can't move, so the g pawn must have.

We now know all the colors.

[title "White to move"]
[fen "8/8/2NBQPN1/2qQKQq1/2Ppppn1/2qPkPP1/2npPpp1/8 w - - 0 0"]


When was the term 'Super Grandmaster' first used? According to the following wiki link,

The unofficial title, "Super Grandmaster", is often used by players to refer to those with a 2700+ rating to distinguish the most serious world champion contenders

When was this term first used and by whom?

As pointed out in the comments, it's nigh impossible to pin down the very first usage, but since you're after a rough idea, I'll get the ball rolling with an initial answer of the oldest definite use I'm aware of; it's from within the last 25 years, so maybe others can improve on this with better answers.

In 1990, there was a tournament held in New Delhi called the Triveni Super Grandmasters Tournament. The joint winners were Kamsky (#8 with a 2650 rating on the July 1990 rating list) and Anand (#19 with a 2610 rating on the same list). I tried to find a full crosstable or participant list for the tournament, but have so far come up empty on such details.

I do know that Judit Polgar (then "only" #108 in the world, though she would crack the top 20 three years later, and the top 10 three years after that) and former champion Mikhail Tal both played. Additionally, it seems this wasn't a tournament exclusively for GMs, but rather one offering lesser lights the chance to play with some "super grandmasters," as Kamsky mentioned in an interview after the tournament that no participants had achieved any grandmaster norms.

Games

Anand-Kamsky, New Delhi 1990
Kamsky-Tal, New Delhi 1990


How do TWIC, chessgames.com, chessbase, etc. keep up to date with new games? Most players use these services to keep up to date on the latest chess results, but how do these services source their databases? It would seem like a prohibitive amount of work to scrape results from various tournament websites, so is there an official source that everyone uses? If it's FIDE, I wasn't able to find it on their site.

Tournaments often have a place to turn in your scoresheets, but what happens between that and the game showing up in one of these databases?

There's no official source for that. Someone just has to download the PGN games manually.

It is indeed a prohibitive amount of work, but we are talking about money here. They are not doing the collection for fun, they are trying to sell their services for something else such as paid membership or book advertisements.

Let's take a look at the TWIC homepage. Please note the paid ads by New In Chess. They're offering you PGN download as a business.


How to improve my early endgame / late middlegame? When I search for books on the middlegame versus the endgame, I usually find discussions about positions that have almost nothing to do with each other: the former being rich with strategies with upwards of five pawns on each side, and the latter being more precise and cut-and-dry, rarely with more than one or two pawns if there's a valuable piece on each side. Discussions of the latter sometimes include vague advice along the lines of "try to reduce to a winning cut-and-dry endgame" to extend the complexity a couple pieces/pawns more. Yet when I reach a point in the game like this:

6k1/5p1p/6p1/2Np1b2/1r1P4/7P/5PP1/3R2K1 w - - 5 28

I feel like I'm playing on nothing more than shallow tactical threats sometimes colored by old adages like Tarrasch's rule, the principle of two weaknesses, bishop and pawn colors, open files, etc. Can anyone recommend me sources of good theory/practice for this stage of the game?

It sounds like you are looking for strategic guidelines in non-theoretical endgames. Then a modern classic is Endgame Strategy by Mikhail Shereshevsky. Strong players tend to like this book, which should tell us something, but I'm not sure exactly what (causation? correlation?).

Another decent choice is Practical Endgame Play - beyond the basics by Glenn Flear. It focuses on so-called NQEs (Not Quite Endgames) where each side has a couple of pieces each, not counting kings and pawns. The chapter on Rook and Bishop against Rook and Knight contains 50(!) fragments from real games with this material balance, the one in your example. At least it should give you plenty of study material.


Is chess a solved game? Chess is a zero-sum game of limited decisions. The number of possible moves at any given point, and the number of possible states of the board, are all finite.

Tic-Tac-Toe, is one of the easiest examples of a solved game. I can't remember how many years it's been since I last lost a Tic-Tac-Toe match. Does any such "optimal strategy" exist for chess?

Is there any strategy that will guarantee the player would grasp victory or, at worst, a draw?

If there is, please shed some light on it.

Because of the observation you make, that the tree of possible game paths for chess is finite, chess is indeed solvable in exactly the same sense that tic-tac-toe is. So optimal strategies for chess do exist; however, no one has any idea what they are. Whereas tic-tac-toe is solved thanks to a quite small space of possible games, chess is nowhere near solved because its space of possible games far outstrips what could be dealt with by current computing technology.

As noted in another answer, endgame tablebases exhibit optimal play for all positions with limited numbers of pieces. So in those settings, we have solutions that are as explicit and concrete as are those for tic-tac-toe. But it's important to note that while one can easily teach/remember the optimal strategy for tic-tac-toe and swiftly become a perfect unassisted tic-tac-toe player, the amount of information behind, say, the 7-piece Lomonosov tablebases, is 140 terabytes. There is no concise description of optimal 7-man strategy that one could learn/remember and then play perfectly without assistance.


Do some chess players actively train moving the pieces on the board quickly? Having spent the last couple of days watching the Rapid and Blitz World Championships I became, once again curious about the following subject.

In some circumstances, especially in blitz games, it can be a slight but significant advantage to be able to perform the move as quickly as possible in a physical or mechanical sense. Now, playing a lot certainly gives confidence and ease, and there are some simple principles (such as short moves cost less time), but I was wondering if some players actively and in a structured way train this aspect of the game. To make this question answerable let me ask specifically:

Are there any  books or other sources that discuss ways to train and to improve carrying out moves quickly (in a physical or mechanical sense)?

However, I would also be interested in slightly more anecdotal answers on this subject. My primary intent was to ask this for over the board games, but I aspects specific to online games are also welcome.

I'm a FIDE master and in my experience I've never come across any material on how to physically move pieces faster. There's not a lot you have to do: pick up the piece, move your arm to where you want to move the piece, and let go. As you play more this becomes second nature, to the point where training wouldn't make much sense.

As for short moves costing less time, this usually isn't a factor in blitz/bullet games; the exception is when you're about to flag and just need to make moves quickly. Then moving a piece 1-2 squares can be better than moving it across the board. Also, if you move pieces that are physically closer to the clock, you can save very small (but possibly precious) amounts of time. So for Black it would be moving pieces on the right side of the board, and for White the left side. Again, such strategies would only be implemented when you're down to literally a few seconds.


Is castling bad in chess? One of my chess opponents said that he doesn't think castling is good because the king is in the corner and it is easy to checkmate. However, many articles and books suggest that I castle early when I get a chance. Why is castling a good move in chess?

Castling is generally a good move because it gets your king out of the center in the early and mid game. The center is contested in the early and middle game. The classical idea behind controlling the center is that with more space to place pieces and maneuver, that player has a positional advantage that can transform into a tactical advantage if their opponent plays imprecisely. Getting the king away from tactics and scary pieces is a good way to avoid getting checkmated.  Once those scary pieces have been traded off, the king is best placed in the center where it is often the most powerful piece of the endgame.
It's true that the king is easier to checkmate in the corner, but the king is also easier to defend in the corner.


Penalty for violating FIDE rule 8.1.2 - writing moves in advance At one of the chess league fixtures recently, one of the players was writing moves in advance of moving the pieces on the board.

As per the FIDE rule 8.1.2 it's forbidden to do so, but in practice what's the penalty for the player who does it? Should it be a verbal warning and loss of the game on a subsequent attempt or something else?

Should it be a verbal warning and loss of the game on a subsequent
  attempt or something else?

It depends entirely on the circumstances, although a player would never be defaulted for the specific reason of writing the move before playing it. (I will return to this point at the end)

A big part of the problem is that years ago young players were taught to write the move down, do a final blunder check and then make the move. If the blunder check revealed a problem or they just had second thoughts they changed what was written and made the new move. This is the nub of "making notes".

First, if as an arbiter, I'm observing a game and the player is consistently writing the move, pausing for reflection then making the move then I will step in and warn him.

If the player is just writing the move and then immediately playing the move then I will not intervene unless the opponent complains but I will speak to player after the game and tell him that what he is doing is against the rules and tell him not to do it again. This is a general principle for very minor infractions when the arbiter intervening would disturb the players unwarrantedly.

Coming back to what I said at the beginning, that a player would never be defaulted for this, we can look at what happened in the Wesley So case which is analagous. He wasn't writing moves down but writing advice to himself about how to play. He was defaulted after 3 warnings but he was not defaulted for writing notes.

He was defaulted for ignoring the instructions of the arbiter which is something different and, in the extreme case that a player continued writing moves down before making them after several warnings from the arbiter, this would also happen. The player would be defaulted for ignoring the instructions of the arbiter. It may look as if it is the same thing but it is not.


What prevents chess engines from being undetectable? I see accounts of people getting banned from sites like chess.com for using engines like Stockfish and Komodo (I admit I have used these engines before, but never in an actual match). Now, I believe there are certain characteristics of these engines that make them easy to detect.  One I heard is the way you move the King, as well as every move being the best move possible (This one could be wrong). But I was thinking... couldn't chess engines not do the things that make them detectable, like play Kings less randomly, play sub-optimal moves in between optimal ones, etc, and become basically, as far as I can notice, undetectable? Is there anything about the way they are programmed that make this impossible or is this because of legality and morality?

Engines have no concept of natural moves and they have no fear. An engine will play for the most advantage, not for the most manageable advantage, even if it allows a fierce attack, because it sees that the attack does not work, while a human would probably prevent an attack and settle with a smaller, but practical advantage.

"Randomly" picking good moves is not easy. The second best move may only be second best if you see a very hard ONLY MOVE which comes 15 moves after. And sometimes, the best move is very obvious, and playing the second best move would be very suspicious.

It is not very known how engine detections on chess websites work, but I have read that they also account for playstyle inconsistency (ultra-aggressive to defensive, even though an aggressive move is available and not much worse), mouse movement, time management.


Is there a method to efficiently generate moves for bishops? I currently have a function which returns the closed off squares for a piece in a particular position based on pieces blocking it. This function iterates over the rays of a piece and is sufficiently fast, but can use a lot of improvement since it accounts for most of the time taken in the move generation.

I have been recently researching on how I can optimise this function and came across this "trick":
https://www.chessprogramming.org/Subtracting_a_Rook_from_a_Blocking_Piece which conveniently uses a formula to instantly get all the moves for a rook. Is there a similar "trick" to generating moves for a bishop while accounting for the blocking pieces?

If you need any clarifications regarding the question, feel free to ask.

Move generators in modern engines do this with lookup tables, which are indexed by the square of the slider and a bitboard representing occupied (impassable) squares that might block the movement of the piece.

There are two main ways of compressing the huge set of possible occupancy bitboards into a reasonable size. Magic Bitboards are often used, which involve multiplying the occupancy bitboard by 'magic' numbers, which are chosen because they empirically map the set of possible occupancy bitboards into a dense range.

A more modern way depends on the PEXT instruction which is available in newer x86 processors. PEXT bitboards allow for the lookup table to be mapped to an even denser range, and also improves lookup times on processors which can run PEXT quickly. However, PEXT is very slow to emulate on older processors, and also seems to be particularly slow on Ryzen processors.


How to survive a Kingside Attack in Chess? When I play the game of chess, I feel that I am quite weak when my kingside is being subjected to attack.

I have two games to demonstrate as an example. I am black in both cases. Can someone place their annotations with analysis to determine my strategic mistakes, and what I should have done earlier to prevent the attack from happening in the first place?

Game 1

[fen "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1"]
1.e4 c5 2.Nf3 d6 3.Bc4 Nc6 4.d4 cxd4 5.Nxd4 Bd7 6.Nc3 Nf6 7.Be3 a6 8.h3 e6 9.Qd2 b5 10.Bd3 Be7 11.a3 Rc8 12.Nf3 Na5 13.Rd1 Qc7 14.Ne2 Nc4 15.Qc1 Nxe3  16.Qxe3 Bc6 17.Ng3 O-O 18.O-O Nd7 19.Qe2 Bf6 20.c3 g6 21.Rfe1 Rfe8 22.Qd2 d5 23.Nh2 Ne5 24.Ng4 Nxg4 25.hxg4 Rcd8 26.Qe2 Be5 27.Nf1 Qe7 28.g3 d4 29.f4 Bc7 30.c4 Bb6 31.Kg2 b4 32.Ra1 a5 33.Nd2 a4 34.Rh1 bxa3 35.Rxa3 Bc5 36.Ra2 Rb8 37.Bc2 Rb4 38.Nf3 f6 39.g5 f5 40.Ne5 Ba8 41.Rh6 Qg7 42.Kf1 Reb8 43.Bd3 Bd6 44.Nxg6 hxg6 45.exf5 Qxh6 46.Qxe6+ Kh7 47.gxh6   1-0

Game 2

[fen "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1"]
1.e4 c5 2.c3 Nc6 3.d4 cxd4 4.cxd4 d5 5.e5 Bf5 6.Nc3 e6 7.Nf3 Bb4 8.Bd3 Bxc3+ 9.bxc3 Nge7 10.O-O O-O 11.Bg5 Bxd3 12.Qxd3 h6 13.Bh4 Rc8 14.Rab1 b6 15.Nd2 Na5 16.f4 Qc7 17.Rbc1 Nf5 18.Bf2 Nc4 19.Nf3 Nb2 20.Qc2 Nc4 21.Qe2 Qc6 22.g4 Ne7 23.Qd3 Ng6 24.Bg3 Ne7 25.f5 f6 26.Nh4 fxe5 27.dxe5 Rcd8 28.f6 Nc8 29.Qg6 Rf7 30.fxg7 Rdd7 31.Qxh6 Rxf1+ 32.Rxf1 Rxg7 33.Ng6 Qc5+ 34.Kh1   *

1st game

As in the second game you gained a good position out of the opening, exchanging the strong dark-squared bishop for a knight. Around move 25 black just seems better having the bishop pair, dominating the dark squares and having no apparent weaknesses.

Around move 25 you seem to start playing without clear plan. A natural plan would be to play a5-b4 (after preparation) which would make white's queenside pawns very weak
around move 30/31 could think of playing bxc4 31 Bxc4 a5 and work against the b2 pawn, or alternatively think of closing the kingside by playing e5 or even g5.
32.. a5 You certainly do not want to recapture a5xb4 (since this would give white a protected passed pawn on c4 the open a file...). That's why perhaps 32.. bxa3 33 Rxa3 a5 (and work against the b2 pawn) or 33 bxa3 (and white has weak a and c pawns) might have been better.
around move 35: Black is still better. You created a weak pawn on b2 and nothing should happen on the kingside since the white king is rather weak. Not sure whether black can achieve much from here. Perhaps you need to create some tactical ideas with a3 later on. First of all I would try to close the kingside/center with e5 which would also make the white bishop even weaker than it is. After black's e5, because of the weak pawn on e4 white is basically forced to respond with f5 after which nothing dangerous should happen to you on the kingside. If needed you can always play f6, g5 and defend the h pawn with heavy pieces from the 7th rank.
36..Rb8!? allows 37 Nf3 which makes closing the center more difficult
around move 40: you allowed the white knight to get to e5. Compare this to the position after blocking the center with black pawns on e5, f6, g5 where white would have virtually no counterplay. With the pinned pawn on e4 black should still be better but now you need to be more careful with tactics compared to the blocked kingside variation.
41..Qg7 Using a queen for the only purpose of defending a pawn  is not something you want to do, but seems to be the only normal  defense. A better (but not that easy to see) choice would have been to play 41..d3 42 Bxd3 Bd4 which prevents the knight sacrifice on g6 because now the square h8 (which in some lines allows the white queen to enter) is covered by the bishop.
43..a3 works here and would allow your rooks to get very active. After 44 bxa3 you can play 44..Rb1+ and white is lost if playing 45 Bxb1
44..hxg6 loses. You could have tried fxe4, but even then white should be much better.

Summary: Out of the opening black had a good position and also created some targets (weak pawns) on the queenside. Intentionally or not intentionally (?) black chose to not close the kingside and to keep the pawn structure flexible. This is not necessarily a bad idea considering the weak white king. Basically you made a choice between: (a) closing the kingside and playing safely for a win (with admittedly decent drawing chances for white) or (b) Keeping the structure flexible allowing additional options in the center in case black cannot achieve anything on the queenside. Unfortunately, black then lost to a tactics (Nxg6). I would not really consider this game an example for a kingside attack, because basically you lost because of that tactics only.

2nd game

You achieved a quite decent position around move 12, having exchanged the strong white bishop on d3 and created a weak pawn on c3. There does not seem to be any attack on the king side threatened soon. Black should be slightly better at that point.

At move 13 you should consider how to continue your play on the queenside. Obviously a rook or two will go on the c-file, the knight seems to have a nice square on c4, but also you might want to use a knight to attack the pawn on c3 from b5 or a4. The queen would have a good square on a5 from where it attacks the pawns on a2 and c3. You started with 13 .. Rc8, which is certainly not wrong, but Qa5 might be more correct as it un-pins the knight on e7 and prevents being locking in the queen after b6.
14 .. b6 makes your play on the queenside much more difficult as your queen cannot go to a5 anymore. And also it prevents activating rooks via Rc6-Rb6 or Ra6. 14.. Na5 might have been better.
18 .. h5 could have been an idea in order to prevent white playing g4.
19 ... Nb2 seems useless unless you want to move the knight to a4.
Activating the queen via Qe7-Qa3 (this does not work yet because after g4 you'd lose the knight on f5, but could be prepared, with h5) or via Qb7-Qa6-Qa3 or Qa5 could be a long-term plan. But first of all you really need  to prevent white from playing g4-f5 here, which is basically the only way for white to gain any counter-play. 19 .. h5 seems like a logical move here, unless you want to go for a passive setup with g6, Ng7 which does not seem attractive to me.
23 ... Ng6!? does not seem like a good square to me. White will want to play f5 anyway and this just gives him an extra tempo since the knight will be attacked.
24 ... Ne7 You noticed your mistake, but as with the Nb2-Nc4 maneuver, you are wasting tempi in a position where you should either play very strongly on the queenside or think of defenses.
25 ... f6? Not a good move as it weakens the light squares and gives the bad bishop on g3 lots of squares if white plays  exf6. Your best option might have been to play with rook against two minor pieces after 25..exf5 26 gxf5 Nxf5 27 Qxf5 Ne3 With the weak white bishop and weak pawn on c3 chances might not have been that bad.
27 .. Tcd8? White is threatening f6 which does look pretty deadly. 27 ... Qc5+ with the idea to play Qe3 looks like an option since exchange of queens would be good for black. If white responds to the check with 28 Bf2 this would block the rook on f1 from supporting the f6 push and would give black another tempo to play Qc7 attacking the e5 pawn again. In fact white's only good option might be to return with the bishop to g3, making this a move repetition..
28 f6 Black is basically lost after this move, so there is no point analyzing further.

Summary: Out of the opening black had a good position. You did not really get anywhere on the queenside though (perhaps because of b6) and also you wasted a few tempi moving knights back and forth. White has basically only one plan in this position which is a kingside attack with g4-f5-f6... When breaking through on the queenside seemed impossible you should have focused on how to prevent white from carrying out this plan. You missed two defensive tactics which could have given you a draw.

A few ideas on what to do in general against this plan in positions like this:

Play h5 to prevent g4 and to strengthen the position of your knight on f5. If white plays h3 with the idea to play g4 sometimes you can play h4 or you can go for a setup (after g4 hxg4 hxg4) with knights on h6 and e7 and queen on d7 all working against f5
Put a rook on the 6th rank (c6 in your case) which could help to prevent f6 later
Escape with the king to the center
Open the center. This is kind of what you tried playing 25 .. f6. However this would have been more effective e.g. with the rook from c8 on e8 defending the knight and putting pressure on the center. Generally opening a center is a good response to a pawn storm.
Be faster on the queenside.

What should you do?

Looking at the two games, I would say that in the second you really encountered a kingside attack which is not easy to defend against and is perfectly possible to lose even with best play. There is no reason that you should lose to the first game's "kingside attack" though, because: you have very good counterplay (b2, e4 pawns), have the option of preventing any of white's activity by closing the center/kingside, don't have many threats to defend against.

Some ideas on how to improve your play against kingside attacks:

Work on your tactics, which is always a good idea. In game 1 you missed 41..d3 and 43..a3; in game 2 you missed 27..Qc5+ and the tactics around moves 25-27 (exchange of two pieces for a rook).
You could also think about changing your opening repertoire to playing for instance 1 e4 e5 which does not run into problems with such kingside attacks as easily. In many of the Sicilians you do run into such kingside pawn storms, similarly in many French and in the Modern/Pirc.
Study how masters handle kingside attacks for pawn structures that occur in your games.
Consider whether you can close the pawn structure on the kingside.
Be quicker with your queenside counterplay (don't fool around).


What is the reason for using gambits on defence? As I understand it, gambits are used in aggressive play, such as in the King's Gambit and Queen's Gambit ...

But:

  What is the reason behind playing gambits on defence, such as
  in the French Defence?

The fact that an opening has the word "Defense" in the name usually signifies nothing more than the fact that it is a move by Black that leads into that opening. For instance, if White plays 1.c4 it is simply called the English Opening. But if, after 1.e4, Black plays 1...c5, then we reach Sicilian Defense positions; or if Black plays 1...e6 instead it is a French Defense. But the only reason the latter two are called "defenses" is because it is Black who chooses to enter each one, and the first-move advantage for White means that in the early stages of the game, Black is "defending" to some degree. This is the same reason why, for instance, when Black plays a certain setup it is called the King's Indian Defense, but when White does the same it is called the King's Indian Attack. The word "defense" in the name of an opening generally means no more than that Black has the choice to enter into it.

But Black's motives when playing one "defense" instead of another vary as widely as chess players do, and many times Black is striving to take the initiative away from White immediately. The Sicilian Defense and the King's Indian Defense, for example, both have rather aggressive reputations. Given the above explanation regarding the word "defense" in the names of openings, your question as stated boils down to, "what reasons does Black have for gambit play?" And to that, I would just say that gambit play has the same pluses and minuses for either color.


pgn-extract suppress output I installed pgn-extract_17.38 and want to suppress the output of

$ FEN=$(echo "1.d4 Nf6 2.Nf3 e6 3. *" | pgn-extract -F)
Processing stdin

1 game matched out of 1.

I read about suppressing methods on the website. But till now it does not work for me. Has any one experience in that tool?

If you add the --quiet option that should do it:

FEN=$(echo "1.d4 Nf6 2.Nf3 e6 3. *" | pgn-extract -F --quiet)

kentdjb (author of pgn-extract)


Engine recommends a move that (I think) loses a pawn [FEN "rn2kbnr/ppp1pppp/8/3q4/3P4/8/PP2PPPP/1RBQKBNR w Kkq - 0 5"]

If white doesn't play Ra1 then black can play Qxa2. But the engine says this is an inaccuracy, and that the best line is e2-e3.

In short: White can sacrifice the pawn on a2 and will gain a quicker development of his pieces. The technical term for this is compensation.

In detail: In the current position, both sides have not developed their pieces. Getting out the minor pieces and castling should have priority.

There are no obvious weaknesses. In some lines (e.g. if white's bishop
 is on f4 or g5 and e3 has been played) white should watch out for Bb4+. Also black has an easy way to simplify/equalize the position further by playing Nc6 followed by e5 or alternatively to attack the center with c5.

Because of this it is essential to act quickly. The white dark-squared bishop probably wants to stay on c1 or d2 for the time being because of the potential threat of Bb4+ (or even Qa5+ exchanging the queens). So the most natural development moves in the position are Nf3 or e3 (making space for the bishop on f1). Either move is decent, but e3 has the advantage that the bishop can quickly go to c4 where it attacks the queen on d5 (or a2 if black takes the pawn).

Looking at the concrete line 1. e3 Qxa2 2. Bd2, you note that white has made two development moves while black has won a pawn but the black queen is somewhat far from the action and in fact is in danger of running out of squares: white is threatening for instance Qc2, Bc4 which would win the queen).  Likely black would have to make another queen move retreating the queen to d5 or e6, losing even more time for development.


Why is Qf3 better than Nf3? I am training with an app and have played about 10 games in my life, most years apart. However, now I became interested in the game.
I have this situation:
[FEN "4kbnr/p2npppp/1p6/4P3/q2N4/P6P/1PPP1P1P/RNBQ1RK1 w k - 0 1"]

I was going to move Nf3, thereby moving the knight to (temporary) safety, protecting the e5 pawn, and having the queen additionally protect knight. However, the app wants me to make the move Qf3.
The only advantages I see to that are d eveloping the queen and having a more versatile queen instead of a knight control centre
But it seems like this should easily cost me the knight. So, can you help me realise why the app is right?

It comes with the threat of Qa8+, which forces black to return the knight.
And white is up material, so exchanges are good.


What is wrong with f2-f4 against the French Defense? [fen ""]
[Startply "3"]
[Title "2.f4 against the French Defense"]

1.e4 e6 2.f4

What is so obviously wrong with this approach? I ask because it is not even mentioned in the complete Black repertoire book French Defense: The Solid Rubinstein Variation by Hannes Langrock http://www.russell-enterprises.com/images/frenchrubinsteinexcerpt.pdf which includes second move alternatives to 2.d4 such as 1.e4 e6 2.b3 or 2.Qe2.

Grandmaster Igor Glek wrote a survey about 1. e4 e5 2. f4 in Secrets of Opening Surprises, volume 8 (2008).
Some quotes:

With 2. f4 we return to the nineteenth century, when modern chess understanding made its first steps. The basic idea is clear I suppose - after 2... d5to play 3. e5! - gaining some space in the centre. So in principle we see the same ideas as in the popular Advance Variation (2. d4 d5 3. e5), but White doesn't permit Black to create immediate counterplay against pawn d4.
...
My opponents usually played in the same way as they would against 2. d4 d5 3. e5 line - ... c7-c5, ... Nb8-c6, ... Ng8-e7(h6)-f5. My reaction was Nb1-a3-c2and then not d2-d4 immediately, but first Bf1-d3. Interestingly, we can already see this manoeuvre in McDonnell's and Labourdonnais' games!

That's exactly the plan Nakamura followed in the game mentioned in the comments.
[FEN ""]
[Event "US Championship"]
[Site "Saint Louis USA"]
[Date "2012.05.19"]
[Round "11"]
[Result "1-0"]
[White "Hikaru Nakamura"]
[Black "Yasser Seirawan"]
[PlyCount "59"]

1.e4 e6 2.f4 d5 3.e5 c5 4.Nf3 Nc6 5.c3 Nge7 6.Na3 Nf5 7.Nc2 h5
8.Bd3 g6 9.O-O Be7 10.Bxf5 gxf5 11.d4 h4 12.dxc5 Bxc5+ 13.Be3
Be7 14.h3 b6 15.Qe2 Nb8 16.Rfd1 Ba6 17.Qe1 Nd7 18.b4 Nf8 19.a4
Bc4 20.Ncd4 Qd7 21.b5 Ng6 22.Nc6 Kf8 23.Nd2 Bd3 24.c4 Kg7
25.cxd5 exd5 26.Nb1 Bc4 27.Qc3 Qe6 28.Nd2 Rhc8 29.Nd4 Qd7
30.e6 1-0

So the answer is: There's nothing wrong with 2. f4 against the French Defense.


I wanted to understand the chess engine comparison. What does this result matrix show? For example in the first row and second column, Stockfish vs Houdini, the result is 27-25+7-3=-16. I understand that 27 signifies Stockfish's number of wins+ draws, similarly 25 signifies that of Houdini. But what does "7-3" signify? and how is the result -16?

And what does the blank in Row 1, column 7 mean? similarly in (6,11), (7,1), (7,10), (7, 12), (10,7), (11,6), (11, 12), (12,7), (12,11). Do they signify that those matchups have never happened? If so Where should I look for if I want comparison of such matchups?

This question may be weird, but please at least guide me where should I ask these questions if not the answer.

@muclux is right on the results. Check his comment. I'll answer what "16" mean.

Scroll further down on the page.

The number is the rating change. Stockfish lost 16 rating point to Houdini, similarly Houdini won 16 points from Stockfish (convince yourself by going to the Houdini vs Stockfish cell).


Longest chess game possible (maximum moves) What is the longest chess game possible in terms of chess moves? I read somewhere that there is a theoretical maximum of 5949 moves. But I don't see any proof and I don't think it is correct.

Can it be infinite?

Source

Some cleaning up is required, I think:

The number on the website you link to differs from the results published in     Bonsdorff et al., Schach und Zahl. Unterhaltsame Schachmathematik. pp. 11–13.
There they say that if the 50-move-rule is mandatory the longest possible game (i.e. where both players cooperate to achieve the weird goal of a game of maximal duration) lasts 5899 moves.
Possibly, the web site used a simpler upper estimate for the "gaps" between pawn moves and captures that cannot be achieved in all occasions.

However, the 50-move-rule (and also the position-repeated-three-times-rule) is not mandatory, i.e. whether or not a player demands remis by that rule is up to him! The players may decide to ignore the rule and play on, thus allowing for an eventually periodic sequence of moves, i.e. an infinite game.


How does the scid opening trainer work I'm trying to use the opening trainer in scid. I've set up a filtered database of master games in a particular opening, as described in the wiki. I was expecting some kind of interactive experience from there but, when I start the opening trainer, it just cycles through the moves in the database then offers me a report. What am I missing?

I'll give instructions for Scid 4.6.4. With this setup, I haven't seen any issues where it moves both sides:

Create a database of openings you want to study. Scid will select randomly from all variations of all games, so make sure you want to train on everything in that database. Open the database switcher and make sure your desired openings database is selected.
Database > Maintenance > Maintenance Window (Ctrl + M). You should see your database name at the top. Next to the name of your database, click the image to the right of "Type Icon:" and select either "Openings for White" or "Openings for Black". Note that this option decides your selection in step 4. Let's say you select "Openings for Black"; the only option you can select in step 4 is to play as Black. If you want to play White, you'll need to either reclassify the database in the Maintenance Window or rotate the board (after you've selected to play black) and it will let you play the White pieces. "Openings for either color" allows you to select playing both sides in the Openings Trainer, but from what I've seen it'll just play one side anyway.

If desired, add additional flags for White or Black openings here in the Maintenance Window. I don't think this does anything for the Opening Trainer.
You may need to restart Scid. Play > Training > Openings. Customize your options (such as which side you want to play) and hit Continue. Play a move and Scid should play the other side if you've selected either White or Black. Once it displays "End of variation" in the window that pops up, you can use the arrow keys to move back to move 1 (or select move 1 in the Notation) and it will randomly select another variation. If you're ever stuck on a move, click "Display candidate moves" in the pop-up and below that button it will show your options.


How does one play against 2. d4 cxd4 3. Nf3 in Sicilian? I'm wondering about the move order 2. d4 cxd4 3. Nf3 in Sicilian. If black does not try to protect the pawn and plays some normal move like 3... d6, 3... e6 or 3... Nc6, then 4. Nxd4 transposes into one of the usual lines. On the other hand,  3... e5 does not seem to be the option, as e. g. white can play 4. c3, and if black captures on c3, it's a Smith-Morra gambit which black has already messed up by playing d5 in one move.

So, are there any options for black that are better than transposing to the main lines? If not, I'm wondering why this move order is much less popular than 2. Nf3.

It seems you only give Black extra options compared to the usual 2.Nf3 and 3.d4

Black can reach whichever Open Sicilian he was aiming for. He has made no concession since ...cxd4 was part of the plan anyway.
As pointed by BlindKungFuMaster, 3...Nf6 will lead either to an Alapin, or to a harmless sub line of the Nimzo-Sicilian (1.e4 c5 2.Nf3 Nf6 3.e5 Nd5, and now 4.Nc3 is considered much better than 4.d4). The small plus side for you is if you want to play an Alapin yet avoid lines without ...cxd4, e.g. if your opponent likes to play 1.e4 c5 2.c3 e6 3.Nf3 Nc6 4.d4 d5: this interesting option is not available anymore for Black.
3...e5!? is actually perfectly playable. After 4.c3 Black doesn't have to take the pawn but can continue with 4...Nc6. This is actually one of Sveshnikov's recommendations for Black vs the Morra in his recently published repertoire against the anti-sicilians.


In the Queen's Gambit Declined, after 1. d4 d5 2. c4 e6, what is the difference between playing 3. Nc3 and 3. Nf3? Here are Chessbase's statistics after 1. d4 d5 2. c4 e6 :

Nc3 - N=116,000 - W=58.2% - Av=2152 - Perf=2176

Nf3 - N=54,000 - W=60.3% - Av=2239 - Perf=2264

.

N = The number of games played
W = White's score in %
Av = The average rating of players playing White
Perf = The average performance rating of players playing White

.

So clearly 3. Nc3 is two times more popular than 3. Nf3. But 3. Nf3 has a better score (though if we calculate Perf minus Av we find +24 for 3. Nc3 and +25 for 3. Nf3, which is pretty close).

.

There are four things you should know:

Firstly, I am an extremely positional player, I don't like sharp and crazy games full of tactics. I would prefer the move which in average leads to the most solid, positional, slow, closed, strategic and quiet positions. I don't know which move that would be.

Secondly, as White, I always develop my King's Knight to f3, not to e2. This is a plus for 3. Nf3, since if I'm going to develop it there anyway I might as well do it right away on the third move.

Thirdly, I like playing (as White) the Exchange Variation (of the Queen's Gambit Declined) very much. Not with Ne2, f3, e4. I play it with Nf3 and a minority attack on the Queenside. This is a plus for 3. Nc3, since it's impossible to get a good position in the Exchange Variation if you begin with 3. Nf3 which loses a tempo.

And lastly, against the Slav, after 1. d4 d5 2. c4 c6, I prefer to play 3. Nf3 over 3. Nc3, because I heard that 3. Nf3 was much more solid and quiet, and that 3. Nc3 can lead to very sharp positions. For example: 3... e5!? looks sharp and crazy, it's possible after 3. Nc3 but not after 3. Nf3. This is maybe a plus for 3. Nf3, since if I already play 3. Nf3 against 2... c6 maybe this means I should also play it against 2... e6.

In the Queen's Gambit Declined, after 1. d4 d5 2. c4 e6, what is the difference between playing 3. Nc3 and 3. Nf3?

With the 3.Nf3 move order your opponent can obtain a favorable position, almost entirely destroying your advantage.

Here is a small example:

[Title "Black dodges the Exchange variation"]
[fen ""]

1.d4 d5 2.c4 e6 3.Nf3 Nf6 4.Nc3 Be7 5.cxd5 ( 5.Bg5 O-O 6.cxd5 Nxd5! ) 5...exd5 6.Bg5 c6 7.Qc2 ( 7.e3 Bf5! ) 7...g6! 8.e4!? ( 8.e3 Bf5! ) 8...dxe4 ( 8...Nxe4? 10.Bxe7! ) 9.Bxf6 Bxf6 10.Qxe4 Kf8!? 11.Bc4 Kg7 12.O-O Re8 13.Qf4 Be6 14.Bxe6 Rxe6 15.Rfe1 Qd6! 16.Qxd6 Rxd6 17.Re8 Rd8 18.Rxd8 Bxd8 19.Re1 Nd7=

With the 3.Nc3 move order, you are on the correct path towards the Exchange variation, but Black has a choice to sharpen the game. He could play 3...c6 offering you the Marshall attack, and even if you decline the offer and try to steer into the Exchange line, he could play ...dxc4 ( immediately or in the next move ) sharpening the game. Do not forget that Black may decide to play ...Bb4 entering the Nimzo-Indian defense which leads to open, dynamic play in most cases.

Be aware that you can not dodge sharp battles with the Nc3 move order, but it is the only correct path to a solid Exchange variation for White.

  Firstly, I am an extremely positional player, I don't like sharp and crazy games full of tactics. I would prefer the move which in average leads to the most solid, positional, slow, closed, strategic and quiet positions. I don't know which move that would be.

You can't achieve what you ask for 100%, since Black has a say too. The best you can achieve is "healthy compromise" -> you can get a positional battle without crazy tactical sparks, but the game will still be dynamic and sharp.

  Secondly, as White, I always develop my King's Knight to f3, not to e2. This is a plus for 3. Nf3, since if I'm going to develop it there anyway I might as well do it right away on the third move.

With the 3.Nc3 move order you can just play Nf3 anytime you want. The point is that you have a choice, that is all...

  Thirdly, I like playing (as White) the Exchange Variation (of the Queen's Gambit Declined) very much. Not with Ne2, f3, e4. I play it with Nf3 and a minority attack on the Queenside. This is a plus for 3. Nc3, since it's impossible to get a good position in the Exchange Variation if you begin with 3. Nf3 which loses a tempo.

Again, the only correct path towards the solid Exchange variation is with 3.Nc3 move order. You can choose between Ne2 and Nf3, it is a matter of taste, but know that Ne2 is a critical line for Black in the Exchange variation.

  And lastly, against the Slav, after 1. d4 d5 2. c4 c6, I prefer to play 3. Nf3 over 3. Nc3, because I heard that 3. Nf3 was much more solid and quiet, and that 3. Nc3 can lead to very sharp positions. For example: 3... e5!? looks sharp and crazy, it's possible after 3. Nc3 but not after 3. Nf3. This is maybe a plus for 3. Nf3, since if I already play 3. Nf3 against 2... c6 maybe this means I should also play it against 2... e6.

Against the Slav move order, you have time before playing 3.Nc3 as he can't respond with a fast ...Bf5 so I would make an exception there and play 3.Nf3 to rule out any sharp play.

Still, I would go for other quiet lines against the Slav, instead of trying to enter the Exchange variation of the QGD. You should consult opening manual to see if there is a safe transposition, otherwise you might get tricked into an inferior position. This should not be a problem as far as I remember, since there are lots of quiet lines in the Slav for White that suit your style.

SUMMARY:

Against QGD play Nc3 and enter your favorite line, but against the Slav stop early sharp lines with Nf3, and do not attempt to transpose into the Exchange variation of the QGD. Instead, head for the lines with Qc2 or similar, these will suit your style.

If you have further questions leave a comment. Good luck and best regards.


What did Benjamin Franklin mean in this quote? I was reading thenarticle at http://www.chess.com/forum/view/general/benjamin-franklin-on-the-morals-of-chess, and in the last paragraph, Ben Franklin says "Snatch not eagerly at every advantage offered by his unskilfulness or inattention; but point out to him kindly, that by such a move he places or leaves a piece in danger and unsupported; that by another he will put his king in a perilous situation, etc."
But he also says "If you touch a piece, you must move it somewhere; if you set it down, you must let it stand." So if my opponent moves their queen to a spot where I could capture her, what would be the advantage of pointing out that his queen is in danger, since he cannot move his queen back to a safe spot (because once they set it down, and therefore must let it stand)?

You hold yourself to a higher standard than your opponent, for politeness' sake.

So you let him play an alternative move after you kindly point out that it was perhaps not the best available, but you are acquiring a habit of caution by adhering strictly to the laws of the game for your own moves.

The point is to be moral, polite and extremely smug at the same time.


Gambits out of Nimzowitsch Defense What are some aggressive gambits that White could use out of the Nimzowitsch Defense? 1. e4 Nc6 d4 d5

1.e4 Nc6 2.d4 d5:

  3.Nc3

scores best for White according to my database and it is the move I play.

3...dxe4

Your opponent can go into the French Defense with 3...e6, but this is not a good French with the N on c6 blocking the c-pawn.

4.d5 Ne5 is the most common.

5.Qd4 Ng6

Now White can consider Qxe4, h2-h4, f3... White has many aggressive options.

The safe 6.Qxe4 Nf6 7.Qa4+ Bd7 8.Qb3 continues to give Black problems.
The pawn sac offer of f2-f3 seems to have clear compensation based on the development advantage it gives.  But the problem with non-queen moves is that they allow Black to play e7-e5 which is close to equal.

  Alternatively 2.Nf3

a common line is 1.e4 Nc6 2.Nf3 offering Black to return to a standard opening with 2...e5.  If 2...d5 you get an odd Scandinvian/Center-counter.  Black usually plays 2...d6 and after 3.d4 Bg4 4.Bb5 a6 5.Bxc6 White scores better.


Engine vs Engine Database Does anyone know of engine vs engine databases? Like stockfish vs leela vs komodo pgns for 1000s of games with a lot of time per move? I want data for how draw rate changes as engine rating goes up, and am willing to sift through the data.
I see there have been tournaments recently, but I'm having trouble getting the data. The more variant the data (multiple engines, multiple ratings, multiple dates) the more useful.

If you go to this site:
https://ccrl.chessdom.com/ccrl/4040/games.html
You should be able to download pgns of games by month, or games played by any specific engine of your choosing.
Also on the home page:
https://ccrl.chessdom.com/ccrl/4040/
You can search around and find stats of how certain engines score against each other.


Is the Queen plus pawn versus Queen endgame always a draw? In a Queen + King versus Queen + King endgame (including zero or more pawns) these is a strong draw tendency due to the fact that a Queen can deliver multiple checks in a row to the opponents open King. My question concerns the Queen+pawn versus Queen endgame. Assuming that the pawn is on its initial square (second rank for white, seventh rank for black), are all these endgames objectively drawn? Second of all, what is the best strategy for the player with the material advantage to aim for a win?

My question concerns the Queen+pawn versus Queen endgame. Assuming that the pawn is on its initial square (second rank for white, seventh rank for black), are all these endgames objectively drawn? Second of all, what is the best strategy for the player with the material advantage to aim for a win?

Emphasis above are mine, and since you have 2 questions I shall answer both separately.

  are all these endgames objectively drawn?

No they are absolutely not!

  Second of all, what is the best strategy for the player with the material advantage to aim for a win?

Without seeing the exact position I can not answer that-your question is too broad-these endgames require thorough study as everything counts there ( the position of the kings, who moves first and so on ).

I can recommend you Yuri Averbakh-Comprehensive Chess Endings ( Volume 3 ) to learn how to win Q+P+K vs K+Q endgames. There you have described patterns for winning with the bishop/knight/rook/central pawn, queen and king vs king and queen.

I have just suggested the above book because it is written for all levels of play-from novice up to grandmaster-so with that knowledge you can not squander your edge, but if you find something else even better for you!

The key is just to learn how to recognize winning position and to learn how to win it.

All you have to do now, is to use this tablebase to see how can you reach the winning position.

If you have trouble finding exact winning moves you can always go through tablebase moves-just click on the notation.

SUMMARY:

Learn how to win Q+P+K vs K+Q endgames->input the position you are interested in into tablebase->if winnable, play through moves to see how to reach winning position.

I know that this might be too broad of an answer to you, but you ask for help in Queen endgames and these are the toughest to master. Just one imprecise move ( not to mention wrong one ) gives your opponent a draw and squanders your edge!

Hopefully this answer helped you a little.

If you have further question leave a comment and I will reply.

Best regards.


What is the draw frequency for 3 consecutive games (same players; amateur level)? In Mr. Robot (TV series) episode "eps2.2_init_1.asec", Elliot and Mr. Robot drew 3 consecutive chess games. They remark it's impossible.

  The odds of that are Impossible.

As far as TV shows go, Mr. Robot is known for its technical accuracy. I was surprised when I heard that line, so I fact-checked it:

From Wikipedia:

  [Frequency of draws] is currently "holding pretty steady around 50%, and is only increasing at a very slow rate".

I understand that figure is for top-level tournaments, not 3 consecutive games from the same 2 players. Is there are any accuracy to that statement in the show? If not, is it different from the 50% rate for top-level players?

Definitely not impossible! It is true that draws are less frequent in amateur chess, and it is also true that draws are less frequent for faster games (how fast was the game in the show?), but even so, let's say that for a blitz game between evenly matched amateurs the draw frequency were 5%, or 1/20. If you played three games, the odds of playing three draws would be 1/8000, which while unlikely, is hardly "impossible". This is assuming that the probabilities are independent, which may not be entirely true but I think is close enough for a rough estimate.

I don't have an academic citation, but if you want some stats for online games you can look at the Lichess opening book: https://lichess.org/analysis . Normally it shows master-level games, but if you click on the settings you can chose to look at Lichess games instead, and filter by rating and time control. For blitz games at rating 1600, the draw frequency is 4-5%, depending on the opening move (the draw is the small gray stripe without a percentage, so you have to compute it by difference):

For the highest ratings, it's closer to 10% for blitz. And for classical chess, as you know, it's about 50% for top-level chess. For amateur chess I'd say maybe 10-20% but it depends on which level of amateur we are talking about. I won't cite the Lichess stats here because even though they have a "classical" category, it's really what would called rapid in over-the-board tournaments (30 min games in Lichess; OTB classical is usually 2 hours or more).


Facebook Messenger Chess Have anyone here experimented the Chess of Facebook Messenger?
I've heard about this and would like to get the comands/ codes to play.

GM Smerdon has written a blogpost about this.

Some of the commands:

@fbchess play  (or @fbchess play white)
@fbchess help  (will give you a list of commands)

Case sensitive algebraic notation:

@fbchess Bg7
@fbchess e4

@fbchess undo
@fbchess resign


A word for the resulting piece of a promotion? I'm looking for a word that represents the piece after the promotion. In a chemical reaction there are the reactants and the products. Is there an equivalent word for product in promotion?
(In case I haven't make it clear: after a8=Q, is there a word for that queen?)

Edit: I was looking for a generic term (preferably one word) for the resulting piece, not a specific type like queen or knight.

Summarizing some suggestions
The following suggestions are from comments and answers (thank you all) at the time I'm editing this: "promoted piece", "promotee", and "new piece".

It is not clear what you are after, if you are looking for a generic term describing a piece that was added in the game during the play then you seem to be after something that is not embedded in the game. There is no such word and there cannot be any because if there was such a word it would suggest that the new piece is somehow different from an equivalent piece that was there at the beginning of the game. But that is not the case the piece into which the pawn is promoted is absolutely equivalent to another piece of the same name and colour.

Occasionally it may be useful to refer to a piece that has just been added (but this you seem not to want to do). There are several reasonable suggestions in the comments I will just add that the Laws of chess use "the new piece" for this purpose (as in "... and the effect of the new piece is immediate" or "...when the player's hand has released the new piece on the square of promotion...", articles 3.7.5.3 and 4.7.3, respectively).


What's my next move against this Caro-Kann variant? I'm a beginner with openings and Steinitz principles, and I'm in the interesting position where I can develop an artificial intelligence which is better than me in chess.

After the e4 c6, I have played the following variant against my machine, where I tried to refuse the Caro-Kann game to see if I can manage outside the commonly known combinations:

[Title "Caro-Kann refutation"]
[StartPly "36"]
[FEN "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1"]

1. e4 c6
2. c3 d5
3. Qc2 Be6
4. d4 Nbd7
5. h3 f6
6. Bd3 dxe4
7. Bxe4 g6
8. Bf4 g5
9. Bg3 Qa5
10. Nge2 h5
11. Bg6+ Kd8
12. Nbd2 h4
13. Nb3 Qb6
14. Bh2 Qb5
15. Bd3 Qa4
16. Kd2 Bd5
17. Rhg1 Rh5
18. Be4 Rh8

At this point I'm stuck and still haven't managed to gain a real advantage and every idea I get seems to lead to a draw.

Were my moves relevant or is my defense fragile? Can I still overthrow black at this point?

There are in fact quite a few mistakes on both sides, but I can't correct the AI, so this is for White:

3.Qc2 is already bad - it is does not contribute to the fight for the center (and this is a fast one, no time for slow moves). After pawns exchange on e4 black plays Nf6 with tempo and gains the "first move advantage".
6.h3 is slow in that it doesn't develop anything and doesn't stop any threat (Black's white bishop already chose a square which is not g4).
10.Nf3 is better than Ne2 - controls more critical square and looks over Black's weakened kingside.
13.Nb3 is a straight up blunder. 13...Bxb3 with threat on the queen forces 14.Qxb3 with time for Black's 14...hxg3 - up a piece.
15.Nc5 is winning. There are many variations here but after knights are exchanged you threaten 0-0-0 with check and some very strong tactics.
16.Kd2 is weak - centralizing the king while still in the midgame is risky and serves little purpose. Better is 0-0 at least.
17.Rhg1 while not a mistake seems uncalled for. The h rook seems better placed at e1 aiming at the half-open file and close to Black's king (with no castle rights). I think that Bxg2 for Black will be too slow as white has chances of trapping Black's Queen with moves like c4, Nc3 and a3 etc.
You have a better position, don't exchange pieces with 18.Be4. Something like c4 forces his bishop away, then follow with something along the lines of Rooks to e1 and d1, N to c3 (not necessarily in this order) and remember that if Black moves Q to a6 you have c5 with discovery of the bishop on the queen.


Is it still possible to develop new openings? I have been using this opening that I accidentally started using a lot and then got good results in Blitz games. I'm almost sure it won't last a chance in standard games but it made me curious about a bigger question:

If I can't find an opening variation (and it really is an opening, say it starts after 3-4 moves from the beginning of the game, not after 20!) in databases, does it mean that it hasn't been good enough to become famous? In other words, is the age of opening theory over with all the stronger ones already being developed and analysed?

Yes, it is still possible to find new openings. The combinatorial space after 3-4 moves is such large, that there are still many uncharted waters in opening theory.

Many of such openings probably violate learned principles and are pruned by experienced players before going deeper into the game tree, but there may be undiscovered gems among them.


How often do grandmasters fail to mate soon when mate in five or less is possible? The recent question, How often do grandmasters miss checkmate? , turned out to be a bit broad. This question asks about a simple subset of that one, which I hope can be answered with some precision.
How often do grandmasters miss an opportunity for a mate in five or less? Since it matters little if the exact move sequence is followed,I will allow a slightly longer series of moves to be considered not a miss. Consider it a "miss" if twice as many moves (ten) are played before the win,or if there is no win.
Consider classical, over-the-board games.

Let me count the reasons....
It all depends!
And there is no way  to answer your question exactly.
GMs do not play by your  arbitrary evaluation method. They play to win or possibly to not lose. While their tactics are  usually very good , missing a mate in 5 while winning the game is more important to them.
Depending on how they feel,  how much clock time they have,  whether they fear their might be a killer move by opponent they missed if they tried, they will go with what they see as the clearest win no matter how many moves (unless time pressure requires them to win faster as in a SD game with a long difficult endgame vs somehow winning it faster like that mate in 5).