# Question
Title: Is it ethical to force a draw via perpetual check?
I was playing this game. I was white. We reached a point where my opponent could checkmate me in one move (by moving Rook to C1) but I forced him to a draw by stating that I would constantly check him to all eternity using my two rooks.

He agreed to a draw but after a while it didn't *feel* right to me. I regretted forcing him to draw, I felt it was cheap of me to do so, and I think that he deserved a win.

So my question is: **Is it ethical to force a draw like this one?**

# Answer
> 15 votes
There is a rules in chess called **Threefold repetition rule**. This rule states that you can claim a draw if you are about to repeat the the position for a third time. This subsumes a situation called **perpetual check** which also leads to a draw.

So what you did in your game wasn't a case of extortion or abusing a flaw in the game - it was completely by the rules and everyday thousands of games are drawn in exactly that fashion.

PS: You also could have stopped the mating threat by playing Rc7, this would have given you a winning position as far as I can see. So by resigning you actually would have turned a winning position into a loss.

# Answer
> 4 votes
This really is a very interesting question. Chess is a game, a social activity, and like other social activities it has developed conventional manners players are expected to follow.

However, the rules of chess have been purposely constructed and refined so that by playing to win—or, if one cannot win, at least to draw—you support rather than contradict the conventional manners of the game.

In your case of perpetual check, the *implicit* question regards which of the two of you, whether the checker or the checked, has the responsibility to yield. In chess, the long-settled convention is that the checked has the responsibility to yield. Indeed, as another answerer has noted, the very rules of the game have evolved to support the view that the checked must yield. Indeed, the *explicit* rules are even better than that, for the checked need not do anything but respond to checks a few times, after which the threefold-repetition rule comes into effect and the game is a draw.

This is normal, perfectly conventional play in chess. Actually, like the pin and the fork, the perpetual check is kind of a cool maneuver; you have to be aware that a losing opponent might do it to you, and you have to guard against this if you can. Perpetual check (formally, a threat of threefold repetition) has already been done this very year in the FIDE Candidates tournament, and was also done in recent years during a World Championship match. No one thought anything of it: each perpetual check was just a normal, polite, standard draw.

# Answer
> 3 votes
Perpetual check is a chess tactic, like any other. And there is nothing unethical to apply a tactic obviously.

# Answer
> 2 votes
In a game of chess you always try to find the best move(s). If you are threatened to be mated, you are allowed to do whatever is possible to avoid this. By forcing eternal chess you make the best move(s) in this situation. From an ethical view this is not condemnable, since you haven't used a trick to gain the draw. Your opponent should have checked if eternal chess is possible before threatening mate and giving you the chance to eternally check him.

# Answer
> 2 votes
There are standard draw protocols, and some of them benefit the player with the lesser, sometimes much lesser material.

One of them is stalemate. The weaker player aims for a position where he cannot make any legal move (meaning that he's probably way behind in material), but is not in check. Draw.

Another is perpetual check. Usually, the weaker player has sacrificed one or more pieces, but if he can check the opposing king between the same two or three squares forever, it's a draw.

A third method is just a variation of the second. If a player can force a position to be repeated three times, with the same player to move, it's a draw. This is usually done by threats against an opposing king, sometimes by threatening to gain a material advantage, and usually by the weaker player.

As long as these draws are forced within the rules of the game, it's ethical for the weaker player to do so. That's just part of the game.

---
Tags: checkmate, online-chess, check, perpetual
---


title: Engame trainer software

text:
# Question
Title: Engame trainer software
I am learning chess endgames, and I am looking for a software/website, where I can just practice end games with a computer having limited pieces.

For example, if I want to practice queen mate with a lone king. I should have only my queen and my king along with the opponent lone king, and the computer should play the opponent move.

Is there any software or website which have this functionality?

# Answer
For Android you have the 7-piece chess endgame training App, with sets of exercises against Lomonosov tablebases and classified by remaining material per side.
> 1 votes

# Answer
You should be able to set up the position in almost any chess playing program. You would likely get the best competition from programs that have access to the endgame tablebases.
> 0 votes

# Answer
Fritz has a mate training function for this. But you can use any chess engine, with any chess GUI to setup a mate exercise position, and play against the engine. You don't need something special.

Stockfish is the best free engine at the moment.

And depending on your operating system, you can find a GUI to use Stockfish.
> 0 votes

# Answer
Chessgym has that option.

You can just log in as guest, chose among a number of standard endgames and play it out against tablebases.
> 0 votes

---
Tags: software, endgame
---


# Question
Title: How do players "see" several moves ahead?
How can you predict what your opponent will play in the next 5 turns, 7 turns, 10 turns?

If the game is like a tree, then the more the turns the more it will branch out.

How can a player accurately predict what their oppoent will play several moves into the future when the number of possible combinations of moves to get ten moves ahead can be ridiculously large?

Please give a detailed explanation.

How do I learn/acquire this skill?

# Answer
> 15 votes
The answer is that you only consider the most sensible and most critical options. This prunes the tree down to manageable proportions.

One easy example would be the fact that retreats are usually not threatening and therefore less likely to be critical. (Of course the downside is that actually dangerous retreats are often overlooked.)

To learn how to recognise potentially critical moves you have to play through master games, solve puzzles and play games. Over time your brain will store typical moves and manoeuvres in certain position. This ability is called pattern recognition. The more patterns your brain stores the stronger its intuitive move suggestions will be, you will be able to prune the tree more.

Another aspect is called "forcing moves". A forcing move is a move that requires a certain response, i.e. severely restricts the opponent's choices. For example checks, threats of checkmate and other kinds of strong threats. If your moves are very forcing the tree will resemble a path, because every step from this path is either illegal or results quickly in very bad things. If GMs calculate very long variations, these usually contain very forcing moves. In positions without forcing moves even the best players don't look very far ahead.

There is also a non-intuitve conscious part to "seeing ahead". Even if your brain provides you with only the most likely good moves, you still have to visualise the outcome of every variation in your head. That requires training as well, for example solving studies or tactical puzzles with long variations.

# Answer
> 2 votes
I would recommend Dan Heisman for detailed explanations of how effective analysis is done in Chess.

http://www.danheisman.com/main\_chess/chess.htm

Unfortunately, many of his articles have gone behind a membership wall now (at chesscafe.com), but not all:

https://www.chess.com/article/view/good-tactics-requires-analysis-and-pattern-recognition

To answer your question in short: you don't (predict 5,7,10 moves ahead); instead you find dangerous moves (of your opponent, then of your own) then look further ahead only on critical moves for stopping/minimizing the opponent's danger while maximizing your own danger.

(Note that in both of Dan's examples at the second link, you only need to "look ahead" at most 2 moves.)

# Answer
> 1 votes
Other answers are also good. But I would explain it simpler.

You just take account of few best moves, you don't care others because you know that they are inferior you can refute them easily. You keep calculating positions which are unclear for you, until you assess them.

For example, if something lets you win a queen in a middlegame position, you know that is almost always winning for you(you assess it winning), and you stop calculating.

Forcing moves let's you go deeper because if there are forcing moves it means there are less options(generally only one option, think about checks for example).

So to conclude, it's generally easy get 5 moves deep, some positions lets you easily calculate 30 moves ahead, it really depends complexity of the position, and experience you have. Crucial thing is, who is calculating deeper and who is selecting candidate moves more correctly, that's the thing that decides the winner in a game.

Think Like a Grandmaster by Kotov is an excellent book which covers thinking processes in chess. I strongly recommend you to read this book.

# Answer
> 0 votes
forced moves and pattern recognition simplify doing combinations

the risk is that some rare move that was overlooked may be better than the obvious 'forced' one or that the pattern has some tiny difference this time and so fails

but for a quick move selection it works well however for postal chess you might want to put more effort into ensuring the moves are truly forced (or at least best for the other side)

# Answer
> 0 votes
One way to see a lot of moves ahead is to play postal chess.

That is a variant that allows both players to work out multiple variations following each move.

# Answer
> 0 votes
Deep chess requires the player to filter out a set of plausible moves given an infinite series of permutations. The filtering, in effect, is dependent on both the player's strength and tactics.

Dependent on both time and position, considering the relative value of a branch down the tree of moves is typically calculated by a human as cumulative "face value" listing each move considered. The best position in a game, however, is most certainly NEVER the sequence of "best moves" looking 2-3 moves deep per turn, for example.

Truly strong players will consider most options beyond the obvious, yielding subtle and deep moves that support underlying tactics and combat human psychology. Check out Mikhael Tal's games -

---
Tags: analysis, strategy, calculation
---


title: Assigning Engines in Arena

text:
# Question
Title: Assigning Engines in Arena
How does one assign a specific engine to a specific color in Arena? I load a PGN file and move to a specific point in the game. At that time I want to assign Engine A to play black and Engine B to play white. Then when I hit the calculate or demo buttons the game proceeds (after selecting "New Variation"). I've spent half the day searching for the answer with no luck. Any guidance would be greatly appreciate.

# Answer
Are you looking for setting up two engines playing against each other? In that case you can use the following in Arena 3.5: Engines \> Tournament.
> 2 votes

# Answer
In Arena 3.5.1, go to **Engines**, load the engine that is playing on engine 1 first (by selecting the engine 1 Radio button at the bottom left of the dialogue box) then load the second engine on engine 2. To Play The engines against each other, click the analyse button
> 2 votes

---
Tags: arena
---


title: Is this position lost for White?

text:
# Question
Title: Is this position lost for White?
```
8/8/8/5kp1/p7/P4K2/1P6/8 b - - 0 1

```

White just played Kf3, thereby gaining the opposition.

If there were no queenside pawns, what is on the kingside would be a "book" draw. That's because the White king can maneuver himself into a stalemate position on his first rank.

But in this position, if the White king can't move, White has to move the b pawn to b3, or to b4 via b3. In either event, Black's a pawn takes it, queens, and wins for Black.

Or does it?

# Answer
Black wins.

Black has a distant passed pawn and Blacks pawns are more advanced. White is bound to defend against g-pawn, while Black can do anything with a and b pawns. And White cannot win a pawn race, because Black is more advanced.

```
[Event "Original Position"]
[Site ""]
[Date ""]
[Round ""]
[White ""]
[Black ""]
[Result "0-1"]
[FEN "8/8/8/5kp1/p7/P4K2/1P6/8 b - - 1 2"]
[Setup "1"]

2... g4+ 3. Kg3 { Option 1, defending against g-pawn, fails.}  ( 3. Ke3 { Option
2, counter attack on the other side, which fails also, because Blacks pawns are
more advanced, Black wins the race.}  3... Ke5 4. Kd3 Kf4 5. b4 axb3 6. a4 g3
7. a5 g2 8. a6 g1=Q ) 3... Kg5 4. Kg2 Kf4 5. Kf2 g3+ 6. Kg1 Kf3 7. Kf1 g2+ 8.
Kg1 Kg3 9. b4 axb3

```

However, if Black wouldn't have a-pawn that advanced, White could catch Black and avoid promotion after dealing with g-pawn.

For example:

```
[Event "Queenside Pawns Shifted"]
[Site ""]
[Date ""]
[Round ""]
[White ""]
[Black ""]
[Result "1/2-1/2"]
[FEN "8/8/8/p4kp1/P7/1P3K2/8/8 b - - 1 3"]
[Setup "1"]

3... g4+ 4. Kg3 Kg5 ( 4... Ke5 5. Kxg4 Kd5 6. Kf4 Kc5 7. Ke5 ( 7. b4+ axb4 8.
Ke3 b3 9. Kd2 Kb4 10. Kc1 Kc4 11. Kb2 Kb4 12. a5 Kxa5 13. Kxb3 ) 7... Kb4 8.
Kd4 Kxb3 9. Kd3 Kxa4 10. Kc4 { Black king is trapped. Draw.}  ) 5. b4 ( 5. Kg2
$2 $19 Kf4 6. b4 axb4 7. a5 b3 8. a6 b2 9. a7 b1=Q 10. a8=Q Qc2+ 11. Kg1 Qd1+
12. Kg2 Qe2+ 13. Kg1 Qe1+ 14. Kg2 Qg3+ 15. Kf1 Qf3+ { And black takes
opposition, which is necessary to promote g-pawn.}  16. Qxf3+ Kxf3 17. Kg1 Kg3
18. Kh1 Kf2 19. Kh2 g3+ 20. Kh1 g2+ 21. Kh2 g1=Q+ ) 5... axb4 6. a5 b3 7. a6 b2
8. a7 b1=Q 9. a8=Q { This is a bit complicated, but according to tablebase,
this is draw.}

```
> 4 votes

# Answer
**The position is definitely lost for white.**

You can convince yourself about this by checking in an endgame tablebase. White either has to allow the g-pawn promotion or let his king be "stalemated", forcing him to push the b-pawn and be checkmated soon thereafter.

```
[Title "Best play according to an endgame tablebase"]
[fen "8/8/8/5kp1/p7/P4K2/1P6/8 b - - 0 1"]

1... g4+ 2. Kg3 Kg5 3. Kf2 Kf4 4. Ke1 g3 5. Ke2 Ke4 6. Kf1 Kf3 7. Ke1 g2 8. Kd2 g1=Q 9. Kc3 Qc5+ 10. Kd3 Qd5+ 11. Kc2 Ke4 12. b3 Qxb3+ 13. Kc1 Qa2 14. Kd1 Kd3 15. Ke1 Qe2# 0-1

```

Or...

```
[Title "Example scenario without g-pawn promotion"]
[fen "8/8/8/5kp1/p7/P4K2/1P6/8 b - - 0 1"]

1... g4+ 2. Kg3 Kg5 3. Kg2 Kf4 4. Kf2 g3+ 5. Kg2 Kg4 6. Kg1 Kf3 7. Kf1 g2+ 8. Kg1 Kg3 9. b3 {or b4; forced, since the king cannot move} axb3 10. a4 b2 11. a5 b1=Q# 0-1

```
> 1 votes

---
Tags: analysis, endgame, pawn-endgame
---


title: Initial position with board "reflected"

text:
# Question
Title: Initial position with board "reflected"
The rule says that the a1 (and consequently the h8) square must be black, in other words, the leftmost square of the first row of each player must be black. With this the kings stay at the right side of the players at the initial position.

I was wondering if there are any significant changes in the game if we start it by reflecting the official initial position. With this the a1 and h8 squares would be white and the kings would stay at the left side of the players.

My thoughts are that there won't be any significant changes, because there is a bijection between all the positions with the two initial positions. In other words, for each position with respect to the official initial position there is an equivalent position with respect to the new initial position (we just have to reflect the board), and *vice versa*.

What you guys think of it?

# Answer
There would be no changes. It's very easy to prove.

Let's start with a board with a1 and h8 are black, and play some moves. After that, imagine that white squares turned into red ones. And keep playing. Then imagine black squares turned into white. And then finally red squares turned into black squares. Would there be any difference in the game? No.

Colors are just for our eyes, not about game mechanics.
> 2 votes

---
Tags: rules, chess-variants, chessboards
---


# Question
Title: What is the best structured resource for self training?
I have been playing and studying chess for quite some time. I have tons of books but it all seems very haphazard. I was looking for some resource or course where things are lined up as sequence of well structured lessons.

My current USCF rating is 1451 and I am unable to break above 1500.

# Answer
I'm reading the Artur Yusupov training course and I can tell you it's really great! But I don't have so many books.

The series is supposed to be a three years training course (but I think it will take a bit longer to me): Fundamentals (1600-1800 FIDE), Beyond the basics (1800-2000 FIDE) and Mastery (2000-2200). Every year is made of three books: Build Up Your Chess, Boost Your Chess and Chess Evolution.

Every book have several lessons (the first one, 24 lessons), each lesson on one topic (Tactics, Strategy, Positional Play, the Endgame, Calculating Variations, Openings, all of them mixed up), and each lesson ends with 12 short exercises (10' each one at most), and it usually takes to me 1:30 to 2:00 hours to finish each lesson with its exercises.

If you want to take a look, at Quality Chess webpage you can find an excerpt with the contents and one complete chapter.
> 4 votes

# Answer
GM Daniel King has a Power Play Training set. It's a Fritztrainer, so very easy to study, better than books. And covers pretty much every aspect of chess. And it's very suitable for your level. If you study it well and complete it, I guess you get +300 USCF in 1-2 year.

I think this is the best resource. I studied it myself as well.
> 3 votes

---
Tags: training
---


# Question
Title: How to handle resignations from unlost positions when learning?
I played a game against bemeurer, a friend of mine who's learning chess. He's only got me to play against but he's learning quite quick.

Of the 8 games we played so far, I won all of them. Most quite easy, but this last one was a tough fight. We play on Chess.com, which has a chatbox.

```

[fen ""]
[Site "Chess.com"]
[Date "2016.03.25"]
[White "bemeurer"]
[Black "Pimgd"]
[Result "0-1"]
[WhiteElo "741"]
[BlackElo "1259"]
[TimeControl "1 in 3 days"]
[Termination "Pimgd wint door opgave"]

1. Nc3 e5 2. a3 Nc6 3. e4 Nf6 4. Nf3 d6 5. Bb5 a6 6. Bxc6+ bxc6 7. d3 d5 8. Bg5 dxe4 9.dxe4 Qxd1+ 10.Kxd1 Ng4 11.Rf1 h6 12.Bh4 g5 13.Bg3 Be6 14.h3 Nf6 15.Nxe5 c5 16.h4 gxh4 17.Bxh4 Be7 18.b4 cxb4 19.axb4 Nd7 20.Bg3 Bxb4 21.Ne2 Rg8 22.c3 Bd6 23.Rg1 f6 24.Nxd7 Bxd7 25.Bxd6 cxd6 26.Nd4 h5 27.Ke1 h4 28.Kf1 h3 29.gxh3 Bxh3+ 0-1

```

Upon making 29. ... Bxh3+, I said "haha, now I get a free rook". My opponent expected that it would have been a rook trade, like 29. ... Rxg1 30. Kxg1. With 29. ... Bxh3+, I expected that he'd be forced to play 30. Ke1, leaving me to play 30. ... Rxg1+, 31. Ksomewhere, Rxa1. Seems like I actually get 2 rooks. After that exchange, the game is obviously lost for White.

So upon 29. ... Bxh3+ and my exclamation, he resigned. Whenever a game ends, we talk about it in a chatroom here on stackexchange, so that I may explain to him how he played and why I am doing what I am doing. To me, it seems he's growing quite well, but I'd like to be able to hand him a fair victory one day.

During the analysis, it seemed that we had actually missed 30. Ke2, and as a result, my opponent resigned even although the reason for resignation was not true.

In a competition, I'd happily take the win, but here, it's not useful for me to take wins - right now I am the better player, and me winning doesn't change that. I've been wanting to play a fair endgame against him to train his skills in that area, but this resignation throws that idea out of the window.

With the game resigned, however, I went and tried to take an analytical look at the game.

```

[fen ""]
[Site "Chess.com"]
[Date "2016.03.25"]
[White "bemeurer"]
[Black "Pimgd"]
[Result "1/2-1/2"]
[WhiteElo "741"]
[BlackElo "1259"]
[TimeControl "1 in 3 days"]
[Termination "Pimgd wint door opgave"]

1. Nc3 e5 2. a3 Nc6 3. e4 Nf6 4. Nf3 d6 5. Bb5 a6 6. Bxc6+ bxc6 7. d3 d5 8. Bg5 dxe4 9.dxe4 Qxd1+ 10.Kxd1 Ng4 11.Rf1 h6 12.Bh4 g5 13.Bg3 Be6 14.h3 Nf6 15.Nxe5 c5 16.h4 gxh4 17.Bxh4 Be7 18.b4 cxb4 19.axb4 Nd7 20.Bg3 Bxb4 21.Ne2 Rg8 22.c3 Bd6 23.Rg1 f6 24.Nxd7 Bxd7 25.Bxd6 cxd6 26.Nd4 h5 27.Ke1 h4 28.Kf1 h3 29.gxh3 Bxh3+ 30. Ke2 Rxg1 31. Rxg1 Rc8 32. Kd2 Rc5 33. Rb1 Bc8 34. f4 Ra5 35. Rb6 Kd7 36. Rb1 Kc7 37. Rg1 f5 38. Rg7+ Kb6 39. exf5 Bxf5 40. Re7 Bg4 41. Rf7 Bh3 42. Rg7 Bf5 43. Re7 Bg4 44. Rf7 Bh3 45. Rg7 Bf5 46. Re7 Bg4 47. Rf7 1/2-1/2

```

It gets stuck on positional repetition with an online chess engine called "GamboChess JS 6.0". Given that the positional repetition is made by white I guess black is playing the stronger position, although it does seem like White is in control, black is just responding to that and white can't break through so they just decided to repeat forever.

Now that I have run a chess engine on the game, though, I can't really go back and offer to play from the last position. I already know my moves based on the chess engine's suggestions, and either my opponent will play the chess engine moves leading to a boring draw, they will slip up letting me win, or the chess engine isn't seeing all the moves it should and the analysis is useless.

---

I have three main questions:

1. How to handle situations like this, where the person you're teaching resigns, and you think it was okay, but afterwards in analysis it turns out it had gone either way?
2. Was the position after move 29 actually lost for White?
3. How to convert a position into a score using chess engines, so that there's a measure we could quickly use to decide who had the advantage?

I can split the questions up into several questions if needed (if that's the case, then please answer just question 1).

# Answer
> 8 votes
1) Unwarranted resignations happen on occasion even in tournament play, sometimes even in a won position. If your student does this in an instructional game, it's a teachable moment. In the present game, you might learn too: saying "haha, now I get a free rook" during the game is distracting the opponent, which is against the rules whether or not you in fact do win a free rook; if you hadn't said that then your student might well have found 30 Ke2 and defended the resulting endgame, rather than resigning out of an abundance of trust in the teacher.

2) Looks like an inferior endgame for White: material is equal, but Black has a distant passed pawn already supported by the Ra8, and also the Knight, though centralized, may have trouble against the Bishop and the a-pawn. 31...Kf7 seems like a better try than 31...Rc8, but I can't judge whether it's actually winning.

---
Tags: analysis, evaluation, resigning, teaching
---


title: What system do DGT boards use?

text:
# Question
Title: What system do DGT boards use?
DGT boards allow it to be connected with a computer, and thus sending it the moves. WHat algorithm does it use to verify the moves pieces?

# Answer
This page contains a lot of information about DGT boards, including the patent, detailed description of technologies and algorithms used. Many additional references are provided, too. It is definitely an interesting read!
> 6 votes

# Answer
The board does not verify the moves played at all. It does not even recognize the concept of a "move" - it just tells you where every piece is when you ask for it.
> 3 votes

---
Tags: software, chessboards
---


# Question
Title: How to play a Grandmaster in a simultaneous?
Would you play well known Opening theory, or avoid it? What other strategies would you employ to beat a GM in a simultaneous? I have my own strategies which I've used. See link in my profile. But what is best?

# Answer
> 10 votes
I've answered a very similar question here

My take is that GM try to avoid calculating, and try to rely on their superior positional understanding. So striving for a tactical position, seems like a good bet. Your game seems to support this hypothesis.

Here is interesting story, that involved somebody I used to know over the internet and Kasparov:

> \[Kasparov\] rather nervously asked me if I had a rating. I replied 2084 and he, not looking very happy, asked why I didn't write it down in front of the board next to my name. I replied that no one asked me too and that the Belzberg people knew my rating and only today OK my playing since I am a client. He then stated that if he had known I was rated that highly he would have played differently rather than getting into a very theoretical line. Being aware of the 2000 cutoff I again appologized for the misunderstanding and we quickly realized that the Belzberg staff had erred in not telling people to write down their ratings (these were different people than from the NYC event). I simply stated "I'm sorry for the confusion, I won't play" and started to get up and Garry, reiterating that he'd have played differently vs a rated expert, started resetting the pieces to the starting position and said we can restart. Being rather shocked by this and what was over a minute of commotion and confusion I knew the gentlemanly thing for me to do was to step away and let someone else under 2000 play.

source

The position was a very sharp double-edged Scandinavian. Something even Kasparov wouldn't want to play against a high-rated player.

# Answer
> 3 votes
A GM that had many simultaneous games experience is the best man to answer your question. But as a chess fan, this is my idea. The best strategy is playing your best game. Play the opening which you know it thoroughly.

Usually GMs avoid positional variants and they try to play tactical and open games in simultaneous matches. I heard from one GM, they force the weaker opponent make a blunder to lose one or two pawns then they simplify the game to reach to an endgame.

So, you can make the game closed and play positional strategies. Avoid simplifying the game and also don't forget a GM always can find a tactical combination just in a few seconds.

# Answer
> 1 votes
Its hard to say how to prepare because you can only play to your strengths and what you really know.Just because Kasparov will find difficulty against the Berlin doesn't mean you should play it against him if you don't understand the subtle nuances yourself.However having said that I've always felt that certain grandmasters are more at home in certain positions than others and it pays to prepare for them as if it was a 1 v 1 game.For e.g When Nigel Short came over to Sydney to give a lecture and play in a simul I did some quick analysis of his games and he doesn't seem to do really well against strong aggressive tactical players like topalov, kasparov, polgar, shirov etc(Relatively speaking of course). He is however a midlegame positional maestro and his feel for shall we say taking care of the pieces (esp the king)in the middlegame are insanely good. So if he had played e4 a sveshnikov would have been played and if he played any other opening other than e4 I would have played a KID set up which in the end was successful but only for a draw.To be honest players at my level only have a good forehand shall we say and any deviation will be inferior for e.g I have played KID and Svesh for the better part of 10years and only 2 years ago have started incorporating e5 berlin/QGD Ragozin setups.It also depends on your own rating (mine at the time was low 2000s)for a 1500 I would recommend just treat it as 1v1 and play to your strengths and incidentally Short did draw to 2! 1500-1600 players in a 30 game simul.He won quite convincingly btw 28.5-1.5(3 draws) and completely routed North Sydney.The point I am trying to make is you have to encapsulate all your experience and knowledge into that one game so really try to play to your strengths as opposed to your opponents weaknesses.I was just lucky that my style matched well to Shorts'. (BTW he is quite the charismatic character)

# Answer
> 1 votes
Some psychologists hypothesized that grandmasters were better at recognizing chess positions that other people. When they ran the experiments, they were proven "half" right.

That is, grandmasters were better at recognizing *standard* chess positions, because of greater practice, and playing them all the time. On the other hand, they were no better than amateurs at recreating random "chess" positions with pieces dumped randomly on the chess board in defiance of chess logic: e.g. White King at e4, Black king at a1, White pawn at h6, Black pawn "behind" it at h4, etc.

So a trick for an amateur is to steer the game into "unconventional" lines that the grandmaster may not be familiar with, and then use the extra time to "think through" these unusual positions, hopefully better than the grandmaster.

To take one example, playing as Black, Queen's gambit accepted is not as well understood as Queen's gambit declined. This is particularly true if the grandmaster is *not* Russian. The Russians have produced a whole set of literature on Slav defenses and other variations of QGA, meaning that if you master the literature better than the grandmaster, you may have a chance.

---
Tags: grandmaster, simultaneous
---


# Question
Title: Static Exchange Evaluation (SEE) without move undo
I read about a SEE without move/undo but they didn't share any simple pseudo code. If the next ply isn't calculated, cant see the recursive nature, Any speculators how this would work without move/undo?

```
int see(int square, int side)
{
   value = 0;
   piece = get_smallest_attacker(square, side);
   /* skip if the square isn't attacked anymore by this side */
   if ( piece )
   {
      make_capture(piece, square);
      /* Do not consider captures if they lose material, therefor max zero */
      value = max (0, piece_just_captured() -see(square, other(side)) );
      undo_capture(piece, square);
   }
   return value;
}

```

# Answer
The pseudocode you copied from the wiki is just the easiest way to make you understand SEE. It is **NOT** used in a real chess engine, because building a `swap list` would be more efficient.

You should check Stockfish. I'll give you some hints here.

1. Goto position.cpp.
2. Find the function `Value Position::see(Move m) const`. This is where SEE is implemented
3. Check this loop:

```
do {
  assert(slIndex < 32);

  // Add the new entry to the swap list
  swapList[slIndex] = -swapList[slIndex - 1] + PieceValue[MG][captured];

  // Locate and remove the next least valuable attacker
  captured = min_attacker<PAWN>(byTypeBB, to, stmAttackers, occupied, attackers);
  stm = ~stm;
  stmAttackers = attackers & pieces(stm);
  ++slIndex;

} while (stmAttackers && (captured != KING || (--slIndex, false))); // Stop before a king capture

```

Stockfish doesn't do exactly what your pseudocode does. It loops for all for possible attackers from the least powerful (`min_attacker`). For each attacker, the engine checks it's value (`PieceValues[MG]`) and add it to the swap list. The swap list will then be looped over for nega-max:

```
  // Having built the swap list, we negamax through it to find the best
  // achievable score from the point of view of the side to move.
  while (--slIndex)
      swapList[slIndex - 1] = std::min(-swapList[slIndex], swapList[slIndex - 1]);

```

Don't be afraid of the while loop, all it does to check if an exchange is good or not. In fact, the wikipedia you stated has the reasoning:

*This uses a trick, equivalent to negamax in tree search, where the loss for the current side is the gain for the opposite side. This can be seen in the expression piece\_just\_captured() - see(square); which is the value of the piece captured (piece\_just\_captured()) minus the gain that the opponent might make after the move by recapturing. If that term becomes negative, one would better choose standing pat rather than to capture, which can be done by a conditional assignment, or by a max function with zero as second argument.*
> 2 votes

---
Tags: engines, programming
---


title: Help me with this puzzle

text:
# Question
Title: Help me with this puzzle
Look at this puzzle:

```
[FEN "r3q3/1pb1rbk1/2pn1p1p/p1Qp1Bp1/3P4/4P1NP/PP3PPB/3RR1K1 b - - 0 1"]

```

The aim of the puzzle is: Black to play and attain a good position. But I can't find a good position here. Then I looked at the solution, which was 1... Nc4!! . But I can't understand what happens after this move. I think both sides are equal. Can anyone help me?

# Answer
> 7 votes
Black will trap the queen on the next move, either with Bd6 or b6. For example:

```
[FEN "r3q3/1pb1rbk1/2pn1p1p/p1Qp1Bp1/3P4/4P1NP/PP3PPB/3RR1K1 b - - 0 1"]

1... Nc4 2. b3 Bd6 3. bxc4 Bxc5 4. dxc5 dxc4

```

and with a queen and a (passed) pawn for two minor pieces, Black will have no problems to win this game.

# Answer
> 2 votes
Wait it is not over yet :)

The queen trap from ..Nc4 can be avoided. White can give a check `1. ..Nc4 2. Nh4 ..Bxh4 3. Bxc7.`

You can also prevent the knight trapping the queen by giving that check beforehand. Thats another way around.

Apologies i am just a beginner, not good with chess notations, but he point is queen can be saved using Whites black bishop. I may be wrong.

---
Tags: puzzles
---


# Question
Title: How to read score from stockfish - inconsistent response every call?
I was setup stockfish with:

```
uci
setoption name hash value 128
setoption name threads value 4

```

That I try to evaluate my first moves to learn how it works (I am programmer) but I received random results.

```
go depth 20

```

First result cp = 16

```
info depth 20 seldepth 30 multipv 1 score cp 16 nodes 1327846 nps 1074309 hashfull 585 tbhits 0 time 1236 pv e2e4 e7e6 d2d4 d7d5 e4d5 e6d5 f1d3 g8f6 g1f3 f8d6 e1g1 e8g8 b1c3 c7c6 f3e5 f8e8 c1f4 f6g4 f1e1 d6e5 f4e5 g4e5 e1e5
bestmove e2e4 ponder e7e6

```

Second result cp = 20.

```
info depth 20 seldepth 29 multipv 1 score cp 20 nodes 4912037 nps 1040685 hashfull 986 tbhits 0 time 4720 pv e2e4 e7e6 d2d4 d7d5 e4d5 e6d5 f1d3 g8f6 g1f3 f8d6 e1g1 e8g8 b1c3 b8c6 c1g5 c6b4 c3b5 h7h6 b5d6 d8d6
bestmove e2e4 ponder e7e6

```

Why each time Stockfish produce something else for 20 depth - different **scores** \- same move **e2e4**?

# Answer
> 3 votes
The reason is simple - `hashing`. The first time you run the analysis, the engine stored the computed positions in a hash-table. This table was not **clear** the next time you run the analysis. Next time, when you ran the same analysis, the engine could search further and thus returned a different score for it's principal variation.

Evidence? Note the node counts was: `1327846` for your first attempt and `4912037` for your second attempt. The NPS (nodes per second) was very close (`1074309` vs `1040685`). Clearly Stockfish used the existing hash-table to skip moves it had already computed in your first attempt.

Note that this is an expected behaviors, clearing hash-table after each move would dramatically reduce the engine strength.

---
Tags: engines, stockfish, uci
---


# Question
Title: chess win expectancy by material difference table or calculator
Houdini Chess engine is said to have a calibrated evaluation in which engine scores correlate directly with the win expectancy in the position. A +1.00 pawn advantage gives a 80% chance of winning the game against an equal opponent at blitz time control. At +2.00 the engine will win 95% of the time, and at +3.00 about 99% of the time. If the advantage is +0.50, expect to win nearly 50% of the time.

Looked around the net but couldn't find a table? Ideally I'd like to see material difference calculator where I would plug in "1 pawn and 1 knight" down.. what is my win/loss expectancy.

# Answer
> 1 votes
There is no such calculator, that's why you couldn't find any.

About Houdini: It's not a fact. They are saying roughly, Houdini evaluation is correlated with win expectancy against the same engine same hardware, in blitz time control. It doesn't have to be the same for other engines, and it's not the same for humans of course.

# Answer
> 0 votes
I believe that 1 pawn is equivalent to 100 ELO points. So if you are playing a 2000 rated player, and you are rated 1500 rook odds makes the game even.

---
Tags: statistics, database, evaluation, psychology
---


title: Positional play: Slav the way to go?

text:
# Question
Title: Positional play: Slav the way to go?
I'm working on my positional play. Exclusively playing correspondence chess at the moment.

For white I play D4 and try for C4 after that.

For Black I play Caro Kann against E4 but am not sure what's most positional against D4.

I'm thinking of Slav, Semi Slav, QGD

For solid long term positional play which one is best investing time in learning in depth?

# Answer
> 2 votes
I recommend to play Stonewall Dutch, quite closed, yet quite active.

```
[Event "Stonewall Dutch"]
[Site ""]
[Date ""]
[Round ""]
[White ""]
[Black ""]
[Result ""]
[FEN "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1"]

1. d4 f5 2. c4 Nf6 3. g3 e6 4. Bg2 Be7 5. Nf3 O-O 6. O-O d5 7. Nc3 c6

```

# Answer
> 2 votes
The Caro-Kann and Slav share similarities, as discussed in the question: What are all the possible combinations of openings which work well together? (like the Slav+Caro-Kann combo).

I play the 2 myself and find that the 2 openings appeal to players who:

1. Prefer endgames with a superior pawn structure, particularly playing against an isolated d-pawn or hanging c- and d- pawns
2. Don't mind exchanging the light square bishop, as in both openings this piece tends to be exchanged for a knight
3. Want a low maintenance repertoire, as the 2 have solid responses to 1. Nf3 and 1. c4
4. Have good defensive abilities, as both have a solid reputation. So, if you play against attacking maniacs or computers often then these 2 openings work well together

---
Tags: correspondence-chess
---


title: Win an exchange vs winning a piece

text:
# Question
Title: Win an exchange vs winning a piece
I'm black. I took the rook and ended up winning the game. Did I make the right choice? Instead of winning a bishop, and after queens are exchanged, i would have got tripled pawns.

The Lichess engine says to take the bishop, then Qxc6 Bxf1, but I'm not convinced by that line. I mean, everyone would save the rook, as mentioned above. I think if I were to take the bishop, queens would be exchanged and white would save the rook.

And says if I took the bishop I'd have 3.6 points advantage, whereas taking the rook is 0.4 only. Again I'm not totally convinced by engines so I'm asking humans. I don't like having tripled pawns. Maybe the computer approach is best, but I don't think humans would play what Lichess suggested.

# Answer
I agree that tripled pawns are not the greatest, but you're getting a piece for those pawns. If you lost them all, you'd more-or-less be even, depending on the position. What a deal!

Here's the position where the queen trade is avoided. Black ends up with a Rook for three pawns. White's doomed, but as long as he can keep the Queens on the board he has hopes for a swindle. He needs to get those K-side pawns rolling! Stockfish rates this at -4.68. Extremely unpleasant indeed.

```

[FEN "2r4r/1k3p1p/p1p2p2/1q2pQ2/5B2/bP6/P1P2PPP/1KR4R b - - 0 1"]

1... exf4 2.Qxf6 Bxc1 3.Rxc1 Qc5 4.Qxf4 Rhe8 5.Qxf7+ Re7 (-4.68)

```

Here's a varation where the Queens come off. White's counter-play simply evaporates. If the first variation is desperate, this one is hopeless. What's the plan for White? I can't see one. Try this - every time Black moves a Rook, think "nu uh" in your head. White has nothing. Stockfish says Black's up by 5.5

```

[FEN "2r4r/1k3p1p/p1p2p2/1q2pQ2/5B2/bP6/P1P2PPP/1KR4R b - - 0 1"]

1... exf4 2. Qxb5 cxb5 3.Rce1 Rhe8 4.c4 bxc4 5.Kc2 Bc5 6.bxc4 Bxf2 7.Rxe8 Rxe8 (-5.5)
```
> 3 votes

# Answer
It is a typical beginner's mistake to overvalue the importance of having a good pawn structure. A friend of mine once gave a whole piece away to avoid getting doubled pawns, and you argue similarly in this position. That is very understandable if you have just learned about hanging, isolated and doubled pawns and want to adhere to this newfound wisdom.

BUT: It is very, very rare that an advantage in pawn structure is worth a full piece. The disadvantage from having doubled or even tripled pawns usually varies between zero and one pawn.

General advice: Don't worry too much about structure or pawns in general, having active pieces is much more important. Also: Having more material is more important, if only because a piece that your opponent doesn't have, cannot become active.
> 5 votes

# Answer
After 1... Bxf1 2. Bxf1 it seems that White can draw the game because of superiority on white squares (White has white-square bishop and Black has a lot of weaknesses on white squares, king is also exposed) and Black's cramped queenside.

But I would go for 1... Bxf1 too in a blitz game, because these lines are too complex for humans, at least for non-masters.

```
[Event "Analysis with Stockfish 6 after Bxf1, depth 30"]
[Site ""]
[Date ""]
[Round ""]
[White ""]
[Black ""]
[Result ""]
[FEN "r4r2/p1p3k1/2p2p1p/2Qp2q1/8/6P1/PPP2P1P/R4BK1 b - - 0 2"]
[Setup "1"]

2... Qe5 ( 2... h5 3. Qxc6 Qe5 4. Rd1 Rad8 5. Qc5 h4 6. Qxa7 hxg3 7. hxg3 Rh8 8.
Qc5 Qh5 9. Qxc7+ Kg6 10. Bd3+ f5 11. Qb6+ Kf7 12. Qc7+ Kf6 13. Qc6+ Kf7 14.
Qc7+ { 0.00}  ) ( 2... Rad8 3. Qxc6 ( 3. Qe7+ Kh8 4. Qxc7 Qe5 5. Qxc6 Rc8 6.
Qa4 Qxb2 7. Re1 Qxc2 8. Qxa7 Qf5 9. a4 Rfe8 10. Rxe8+ Rxe8 11. a5 Re1 12. Qf7
Qe6 13. Qf8+ Kh7 14. Kg2 Qe4+ 15. Kh3 Rxf1 16. Qf7+ Kh8 17. Qf8+ Kh7 { 0.00}  )
3... Qe5 4. Qc5 Rf7 5. Rb1 h5 6. Qxa7 h4 7. Bg2 hxg3 8. hxg3 Re7 9. a4 d4 10.
b4 Qf5 11. Rc1 Qg5 12. Rb1 Qf5 { 0.00}  ) ( 2... Rab8 3. Qxc6 Qe5 4. Rd1 Rb6 5.
Qd7+ Rf7 6. Qg4+ Kf8 7. Qc8+ Kg7 8. Qg4+ { 0.00}  ) 3. Qxc6 d4 4. Bd3 Rab8 5.
b3 Rbd8 6. f4 Qe7 7. Qb7 Rd7 8. Qxa7 Qe3+ 9. Kg2 Qd2+ 10. Kg1 Qe3+ { 0.00}

```
> 1 votes

# Answer
I would take the piece. As a rule of thumb, it is easier to fight up a piece instead of fighting between two pieces. That is with a Bishop on d3 versus a Rook on e8, you can see it is harder to penetrate than if White had no pieces to defend the entry points.

The triple pawns do look horrible but are helpful. Rb8 to try and eliminate one of the pawns is a bad idea as it gives White a half-open files to attack your pawns. A rook will go to d8 then to d6/5. The pawns will be undoubled(untripled) or you will get total control over the open file. The king and a rook on d7 will prevent any play on the e file.

The Bishop is restricting the King, even if it's only for a couple of moves.

```

[fen "r4r2/p1p3k1/2p2p2/6p1/2p5/6Pb/PPP2P1P/R4RK1 b - - 0 1"]

1...Rad8 2. Rad1 Rd6

```

I skipped a White move just to illustrate the point.
> 0 votes

---
Tags: analysis
---


# Question
Title: Proven ways to improve calculation speed
I've been working on my tactics using on-line resources like Chess Tempo. I found my improvement (as measured by my CT rating) over the last few months to be encouraging, but I struggle to translate this into significant OTB results. I *do* find that I make far less obvious tactical errors when not in time pressure, but when the clock starts going low (as it usually does by the end of the middle game stage for me) I still tend to make mistakes that I can only describe as shocking.

I'm in a stage where I can more or less understand the tactical motifs presented to me *eventually*, but not in the time frames that are typically useful for real OTB play.

Are there proven or known methods for speeding up tactical evaluations and calculations? Things like

* Do blitz-style puzzles. The way blitz mode seems to work on sites like CT is that you have a limited amount of time to solve the puzzle - but my fear is that this will simply cause me to fall back on intuition rather than actually improve calculation speed.
* Do the same puzzles over and over? I'm worried that once I've memorised a puzzle, then I'm not doing so much calculation as memory retrieval.
* Just continue doing normal puzzles and calculation speed will improve by itself? Seems like this could take some time ...

Any other/novel ideas that I need to consider?

# Answer
> 18 votes
You say: *"Do the same puzzles over and over? I'm worried that once I've memorised a puzzle, then I'm not doing so much calculation as memory retrieval."*

Memory retrieval is **exactly what you should be doing**! The brain improves recall not by repeated input, but by repeated output. This is why reviewing notes is a terrible way to study for a test, and why memorizing and recreating your notes from scratch is what top performers do.

The concept that should be driving your improvement is **chunking**. Chunking is the process whereby you are able to immediately recognize more complicated concepts **without thinking**. You still calculate during a live game, but instead of spending 60 seconds working out a tactic, you should learn to see that tactic immediately so that you can spend that 60 seconds on something important. If you cram tactical patterns into your brain, and learn to see them in less than 1 second, while your opponent is spending 30-60 seconds reinventing the wheel, you are going to crush your opponent. On the flip side, if you are trying to calculate everything at the board, you are going to lose. You improve when you are away from the board. Once you are at the board, you only play. You only have the skills you developed away from the board.

An example of chunking is when you learned to read. First you learned letters, then small words, then bigger words, then phrases, and sentences. Now when you read, you do not look at some writing and say, "there is an H, there is an I", nor do you even look at it and say, "there is the word Hi". You see the word "Hi" and you immediately understand the meaning without thinking.

Learning to walk is another example. As an adult, you do not think, "move the left foot, catch your balance, now move your right foot". No, you walk down the street without thinking. If a car is going to hit you, you run as fast as you can without thinking. Your body and mind learned how to handle these more complex situations and they know what to do without thinking. The same happens with chess improvement.

For chess, you want to reach the point where a simple tactic presents itself on the board, and it pops off the board at you without thinking. Once you can do this, you can move on to more complex tactics and combinations that require deeper calculation, but until you can recognize simple tactics without thinking, your mind is moving far too slow to attempt deeper calculation during a live game. As long as you are trying to do difficult tactics problems involving 5-move combinations, before you can see simple tactics instantly, you are never going to improve.

The approach I have seen recommended by masters (NM Dan Hesiman, GM Rashid Ziatdinov, among many others), is to get a simple set of tactics problems such as John Bain's *Chess Tactics For Students*, and you do the same tactics problems over and over. Your goal is not to figure out the tactic on your own. The goal is to get as many patterns into your brain as you can, so that when you see a similar pattern during a live game, it is immediately clear to you without thinking. Doing tactics problems is not about achievement and getting a good percentage correct. It is only about cramming patterns into your brain. That means, if you do not see the answer quickly, look at the answer and move on.

The plan is:

1. Do simple tactics problems over and over, until you can fly through all of them without making a mistake.
2. If you don't see the answer after 30-60 seconds, look at the answer and move on. Come back to the problems you missed later.
3. Stick to one tactical theme at a time. Once you have mastered one tactical idea, only then start another.
4. GM Ziatdinov recommended this approach: Number your list of tactics problems. Start doing problems 1-10 until you can do them all perfectly. Then do problems 11-20 to perfection. Then repeat problems 1-20 to perfection. Now do problems 21-30, then repeat 1-30. Repeat this until you can do all problems perfectly. He had a list of over 3000 tactics problems on his website, and he said if you followed this approach you would have the tactical ability of a grandmaster.

# Answer
> 6 votes
I'd just note that pattern recoginition is only one element of calculation. Yes, drilling lots of simple tactics repeatedly is useful and I'm not disputing the importance of that (I've done 7 circles myself).

But that's not the entirety of calculation, and there is a problem with believing that it is. For one, most tactical exercises have a very clear conclusion -- you use some tactical device to win a piece, deliver checkmate, or say promote a pawn. But often in real positions you won't know when to stop calculating a forced line, and you have to develop your intution a bit to know if you have calculated enough. Also, those clear conclusions (winning material or delivering mate) don't help you learn how to evaluate positions -- you win a piece, and move on to the next puzzle.

Calculation is a broader more difficult process with its own logic, like which candidate to calculate first, how to 'trim' branches, how to choose from several good evaluations (or the opposite problem -- the least bad), and learning your calculation blind-spots like residual images, or geometric motifs like backwards piece moves. The patterns that you learn through drilling tactics will help you immensely with calculation, since you'll be able to see things quickly like ("If I play move A, he can't play move B because of \[insert tactical theme here\]").

Learning the basics of calculation is rather simple, but implementing it is really hard. Try writing out your analysis of complicated positions, and then comparing your lines against the author's. Do this with/without a time limit, and with/without moving the pieces. If you actually attempt this you will find at first that you are very bad at calculating, and will become disheartened...well, at least I did! But over time you will get better and better, and you'll learn lots of calculation shortcuts. Most importantly you'll learn what your true weaknesses are and can focus on them. I kept a running list of my mistakes, and over time have reduced the number of mistakes I make. For example I learned that I had problems calculating accurately when there were captures for both sides in different parts of the board, so I focused on them until I felt I totally understood them...now I actually get excited when I see these positions!

To make it easy on yourself, you can try writing out your analysis of mate-in-2 problems. The evaluation at 4-ply (not 3-ply!) must always be checkmate, and you get to focus on finding lots of good candidate moves (a common calculation pitfall is not searching for enough candidates). Then move on to more and more complicated positions, like king hunts! Eventually you will be able to calculate complicated positions fast.

So please do keep drilling those patterns, but also try learning and practicing real calculation!!

# Answer
> 4 votes
I strongly believe that doing tactical exercises is exactly the way to go. In my experience you will realize the improvements very soon. I think that is really a good idea to also redo puzzles you already solved. Of course you will memorize parts of the puzzles. However, if you have sufficiently many puzzles available, this is not such a big issue and you will actually absorb the underlying patterns, which is a good thing as it will allow you to spot critical ideas more quickly.

For me it is often the case with puzzles I have solved before that I remember the puzzle after I have found the correct first move. I think it is then a good idea to actually go through all the variations again to really hone your calculation skills. If you stop after finding the right move without verifying it, you will likely not train much more than your memory.

I would argue against using Blitz puzzles or games for improvement. After all, if you have trouble finding the right tactical shots under time pressure, then why should it help to constantly put yourself under time pressure? In particular, when playing Blitz games, it is quite likely that you will continue to miss tactical opportunities and thus not learn as much as you would from slower games or tactics puzzles. Of course you can gain the same from Blitz games if you are willing to analyze them afterwards... but who does that seriously?

# Answer
> 2 votes
You may find the combination quicker by looking for these moves (in this order):

* Checks
* Captures
* Attacks
* Other move

You may also need to improve your time management.

# Answer
> 1 votes
Intuition is what makes you good at calculation. Intuition tells you what to think first. The best way to decrease blunders and mistakes in time trouble would to play blitz. This way you get to experience a lot of time pressure scenarios in a relatively short amount of time. Also, playing blitz really helps with spotting simple tactics quickly. It trains your intuition. Bullet chess is also useful in helping chess players familiarize with how the pieces move and train the chess player to avoid hanging pieces. Of course bullet chess is not the primary means of improvement but in that area it may be helpful.

# Answer
> 0 votes
A great way to get out of logical mind is: to hold a pencil upside down and draw with it.

It's like looking from right to left in army cadets: because when you learnt to read from left to right you also learn to skip bits visually as an externality when looking from left to right also.

Basically, slow down. Be confident and be organised.

Don't play blitz chess if you want to win- but we all play for different reasons.

---
Tags: tactics, training, calculation
---


# Question
Title: Exchanged Slav defense. Gambit the c6 pawn. Why not?
\[Update:\] It's called "Tan gambit" after an Alekhine game. Analyzed below. White should dicline the pawn, since. It can be played as a drawing line for black (no queens).

1. d4 d5 2. c4 c6 3. cxd5 Nf6!?

This seem to me a good gambit line. I think it's a good way of playing but no one does according to www.365chess.com Some people find exchange variation boring. What is the reason that no one is playing it?

Take a look at the position after 1. d4 d5 2. c4 c6 3. cxd5 Nf6 4. dxc6 Nxc6 5. Nf3 Bg4 6. e3 e5. Black is very active.

Of course white can avoid it by 3.Nf3. Meaning that slav players still have to know the exchange variation. A gambit does not need to be 100% correct. But a gambit no one is playing?

(I found it via 1.d4 d5 2. c4 Nf6. With no one I don't mean 0).

```
[FEN ""]

1. d4 d5 2. c4 c6 3. cxd5 Nf6!? (3. cxd5 cxd5) (3. cxd5 Nf6 4. dxc6 Nxc6 5. Nf3 Bg4 6. e3 e5)

```

\[Update\]: I used lichess (poor) analysis feature to analyze some games. \[Between strong players\].

5. Nf3 Bg4. \[What I would play\].

7. Be2 \[What I would be most afraid of\]. ½-½, Reinhold (2139) vs. Stevermueer (2150)

7. Bb5 \[Messy internet game\] 0-1, Drozdovskij (2509) vs. Dobrov (2515)

5. Nf3 e5. \[Queens are exchanged\].

6. dxe5 1-0, Sandipan (2637) vs. Elorta (2363)

6. Nxe5 ½-½, Vorobiov (2577) vs. Zvjaginsev (2646)

5. Nf3 Bf5.

5. Nf3 Bf5 1-0, Alekhine vs Tan

# Answer
> 5 votes
If you want to play this gambit, the best way to get there is by playing 2...Nf6!? 3.cxd5 c6!. White is almost certain to play 3.cxd5 which is both the natural move and the theoretical refutation of Nf6. Of course he can still ignore your pawn on c6 and transpose to the Exchange Slav, but at least with this move order it's not a sure thing that he wanted to play the exchange variation.

The gambit 1.d4 d5 2.c4 Nf6 3.cxd5 c6 was played in the game Udovcic–Canal, Venice 1953. (Thanks to @r4 for the link.)

# Answer
> 5 votes
In the chessok opening tree there are 28 games with this gambit. Going by the computer evaluation it seems to be playable, but the score is atrocious (\>80% for white).

So here you have a gambit that is pretty unknown, scores horribly and can easily be ignored if white is not in a mood for adventures. Also it doesn't seem to lead to dangerous complications as far as I can see. There is no automatic attack on the white king, in the worst case white just returns the pawn.

All in all not very surprising that it is rarely played.

# Answer
> 2 votes
Black is active, but he's hardly "sac-a-pawn" active. Once white finishes his development and places his rooks and pieces on the open files and lines, I see no way for Black to stop white from exchanging pieces to a safe pawn up endgame. If I'm giving up a pawn like this, I want activity and something dynamic, like the ability to keep my opponent's King from castling. I just don't see enough from this pawn sac to see it as any good. Maybe in blitz once or twice. But I would hate to have to sit through a classical time control game with this position.

---
Tags: opening, slav-defense
---


title: Queen's gambit continuation

text:
# Question
Title: Queen's gambit continuation
I have reached this same position a number of times, what would be the most sound continuation for white?

```
[fen "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1"]
1. d4 d5 2. c4 e6 3. Nc3 Nf6

```

Two moves that come to mind are Bg5 or Nf3.

What are your thoughts and ideas behind the next move?

# Answer
According to Hans Berliner, correspondence chess champion, Bg5 is the best. From his book "The System. A World Champion's Approach to Chess" he stated, and Fischer agrees, that Bg5 maintain the most amount of pressure. Nf3 is not as good, because you has three major plans in the QGD exchange variation and only one has the knight on f3.

My opinion is that Bf4 is stronger below master level. I like the idea of Bxb8, not having the question put to the bishop on g5, and it reduces the possibility of Bd6. There are disadvantages to putting the bishop of f4.

The answer depends upon what type of positions you like to play. For positional games, the knight goes to f3, for center control and kingside attacks, the knight goes to g3 via e2.
> 5 votes

# Answer
cxd5 because it's forcing. You can develop the Bishop after e4 which further antagonises the centre and double central pawn moves are classed as tempo!

If you don't receive negative feedback on this move I would try it.

Some might call this swapping a wing pawn for a central pawn... and it half opens the King file!
> 0 votes

---
Tags: opening, theory, queens-gambit
---


title: Is the pawns only variant a draw?

text:
# Question
Title: Is the pawns only variant a draw?
In the pawns-only variant of chess, each side starts with 8 pawns and a king on the usual squares, no pieces, with other rules being the same as in regular chess, including promotion.

While general consensus is that chess is a theoretical draw, with best play by both sides, this is not proved because of its complexity.

The pawns-only variant looks more amenable to computer analysis.

In the pawns-only variant, is it possible for Black to imitate White or otherwise create a blockade? Is the pawns-only variant a theoretical draw?

# Answer
I setup the position using this FEN String

```
4k3/pppppppp/8/8/8/8/PPPPPPPP/4K3 w - - 0 1

```

Using a grid engine cluster with 24 nodes, each node having 16 cores at 3.2 Ghz with 60gb of ram

The engine used was Houdini 4 pro (allowing multiple cores)

After analyzing for several days ( 4 days 12 hours 2 minutes and 15 seconds to be precise) the engine scored the position 0.00 flat with the suggested move line

```
1.d4 d5 2.Kd2 Kd7 3.Kd3 Kd6

```

Of course this is not nearly a bruteforce method, but i believe it is safe to say this is a draw. Of course @Rauan Sagit is correct. Correct play comes with intimate knowledge of pawn endings and will be even harder to achieve correct play against a skilled opponent
> 11 votes

# Answer
**EDIT**: Now that I look closely, I have solved a different variant than what was asked. Probably this is interesting anyway :) The variant's rules are described here: http://www.chesscorner.com/tutorial/basic/pawngame/pawngame.htm

I have written a piece of software to solve this. Contrary to my and other people's expectations, and barring bugs, it shows that the game is actually a win for white. Without en passant it was a draw.

The only winning opening moves for white are **1. b4** and **1. c4** (and the symmetric **1. f4** and **1. g4**).

Curiously, all other white opening moves are a win for black. **1. d4** is refuted by **1. ... b5 0-1**; all other black responses are wins for white.

I put the code here: https://github.com/sliedes/pawnsonly. With the default setup it uses 25 gigabytes of memory for the transposition table and I seem to remember it takes a few hours to solve the 8x8 case. I have not tested how slow it is with less memory.

Here are some results of the first two or three moves:

Some of the lines end with "1/2-1/2+" or "1/2-1/2-". "1/2-1/2+" means that white can force at least a draw, and no further search was done because this information was enough for perfect play from the starting position (so it might also be a white win). Correspondingly, "1/2-1/2-" means that black is able to force at least a draw.
> 9 votes

# Answer
Yes, my guess would be that the pawn-only chess variant is a draw with exact play from both sides. Yet, it is of course possible to win for either side, as long as you know what plans to choose between. Since the kings are the only pieces left on the board (apart from the pawns), they will play a key role. The goal will be to create weaknesses in the enemy pawn structure and invade them with the king. Also, to have a good understanding for which pawn endings that are drawn and which ones that are won (e.g. the distanced passed pawn). So while it is objectively drawn, it is still hard to play over the board against a skilled opponent.
> 3 votes

---
Tags: theory, pawns, draw, chess-variants, pawn-endgame
---


# Question
Title: An efficient program, which generates all next moves for all pieces in C/C++
I am looking for an efficient (fast) program to generate next moves for all pieces.

I need it in C++, because I will program in C++.

# Answer
http://support.stockfishchess.org/discussions/questions/1422-generation-of-next-moves-for-all-pieces

You should use Tord (the person who wrote Stockfish)'s C++ move generation code. It's easy, simple, fast and good. It uses magic bitboard.
> 0 votes

# Answer
I think it is unreasonable to ask for this as a stand-alone program because its implementation will be very dependent on the design of your program as a whole. In particular, it completely depends on how you are storing each position: how are you representing the board and pieces? How do you keep track of where each piece is after each move? How do you know which squares a piece *can* move to (is there a piece there already? Is there a piece blocking the bishop's movement as it goes from c1 to f4?)?

Of course, once you have a implemented all of the above *perfectly* then the problem of generating the moves that each piece can make becomes quite easy: simply iterate over every piece and for every piece iterate over all of its valid moves (how you store moves is, again, entirely up to you).

Finally, this is a great resource that gives a good overview of some important topics in chess programming.
> 3 votes

# Answer
Representing Moves found via BitBoards, applying them, and removing them provides a good overview of move generation using the fastest method.

I use a different method relying on three arrays.

key\[\] = {1, 2, 4, 8, 16, 32, 64, 128, ...} // bit test aligned to movement.

movement\[\] = {1, -1, 8, -8, -9, -7, 9, 7, -17, -15, -10. -6, 6, 10, 15, 17}

movementkey\[64\] = {...} // bit set if move is possible.

This array is setup in such a way that if the bit is set, the corresponding movement is allowed. For example, if the third bit is set in the movementkey array, represented easily by key\[2\], then movement\[2\] is a legal square.

Loop through the pieces.

P: check based upon color

N: loop through last eight indexes.

B: call Slider function with index value of 4.

R: call slider function with index value of 0.

Q: call slider function twice, with 0 and 4.

K: simple one square movement.

check for EP, and castling.

The Slider function:

tosquare = fromsquare

loop from index to index + 4

if bit is set fromsquare += movement

if empty addmove and continue

else

```
if NotOwnPiece addmove
break

```
> 1 votes

---
Tags: engines, software
---


title: A quiet mate in two

text:
# Question
Title: A quiet mate in two
I teach chess to children and a colleague of mine told me of this position to show to the kids. Black plays and gives mate in two. It seems an easy position but the children I teach had difficulties with it because they think that the only way to mate is capturing as much pieces of the opponent as possible in the process.

```
[fen "7r/8/8/5k2/4q3/8/6PR/r5RK b - - 0 1"]

```

**Black plays and gives mate in two. What should Black do?**

# Answer
> 5 votes
\[*Corrected*: most of the alternative solutions I suggested fail to g4+\]

There must be some mistake in the diagram, because R(either)xR+ is a non-quiet move that forces mate in 2. Quiet moves don't work because of the defense Rc8+ or Rxh8. Except that the FEN indicates that the wP is on g2, not b7 as it seems, and that makes Qa8! a quiet solution (Zugzwang: if RxR(either) then QxR is mate; other Rook moves are captured by a Rook for mate; and the pawn is still pinned). To make this unique the Queen can be put elsewhere on the diagonal, like d5:

```
[fen "7r/8/8/3q1k2/8/8/6PR/r5RK b - - 0 1"]

```

I see that **Dag Oskar Madsen** already suggested this fix in a comment.

Possibly of interest: while trying to Google this position I ran across this mate-in-2 problem, credited to T.A.L.Herlin 1852, which might have been the inspiration for the present problem though its solution is not as nice or as quiet:

```
[fen "kr5R/rp6/8/8/4Q1K1/8/8/8 w - - 0 1"]

```

Solution:

> 1 Qe8! (threat 2 QxR#) Rxe8/Ra4+ 2 Rxe8/Qxa4#!

# Answer
> 1 votes
A quiet move: 1... Qa8, keeping the pawn pinned, and white will be mated next move.

When teaching kids is important do show MATE IN ZERO FIRST, so MATE IN ONE and so on.

Never give a child a problem she can not solve. Because success is stimulating and a failure is depressing and could be mortal.

# Answer
> 0 votes
Black to move and mate in two, right? Is it as simple as

```
Rxh2+, Kxh2
Qh4#

```

# Answer
> 0 votes
`Quiet move means "A move should occur without a capture or a mate".`

Sure there sacrificing a rook lead to mate in 2 moves, but it isnt a solution. You should look for positional play.

If you are looking for a quiet mate without any captures (rook sacrifices), just position the Queen to

```
..Qe1 or ..Qh4

```

It is a great example of positional play. No captures or mate!

---
Tags: checkmate, teaching
---


title: Unusual chess notation

text:
# Question
Title: Unusual chess notation
I recently bought a chess book that had unusual chess notation, such as B x KP; P X B, Q - R5

Does anyone know what type of notation this is and how to read it?

# Answer
That's **descriptive notation**. Click that to go to the wiki page.

It is an obsolete notation, having been replaced by *algebraic* or *figurine algebraic notation*.

B x KP means, Bishop (B) takes (x) Kings (K) Pawn (P).

Q-R5 - Queen (Q) Moves To (-) Rook's (R) Fifth square (5)

Then there are ways to show castling, etc.

EDIT - doubled pawns. Descriptive Notation doesn't care how pieces got on the squares where they sit. Just name the piece and where it is going. If you were white and had a pawn on e4 and another on e6 (or K4 and K6, in descriptive) and you moved the pawn on e6, your move would be P-K7.

One thing about descriptive, is that the squares are numbered with respect to the side that is moving. Say you as White wanted to move your Queen from her initial square to Black's queen's home square (Qd8 in algebraic). Your move, as white, would be Q-Q8 (Queen moves to the Queen's eighth square). Now suppose you as black wanted to move your queen to white's queen's home square (Qd1 in algebraic). This move would also be Q-Q8. Both moves are notated with respect to the side making the move.
> 12 votes

---
Tags: notation
---


title: How to blunt the Albin Counter Gambit?

text:
# Question
Title: How to blunt the Albin Counter Gambit?
I dislike open, highly tactical games. I wouldn't mind them so much if I won them, but that isn't what happens.

I was recently destroyed by the Albin Counter Gambit. I'm curious if there is a known effective way of declining the gambit, blunting black's counterattack, or otherwise maintaining a closed position?

# Answer
> 17 votes
The Albin Countergambit is not to be feared, particularly. White does quite well after the simple `3. dxe5`. My chess database of master games shows that white wins or draws 80% of the games after `3. ... d4` which is Black's best response.

*Now, before I go down the rabbit hole, please bear in mind that strong masters probably don't visit this site. For amateurs, almost anything is playable. In any of the games we play, a master could win either side on any move as long as the game isn't blatantly lost. The moves are there. So temper everything I say regarding what is and isn't playable.*

This is one frequently played variation:

```

[fen ""]
1. d4 d5 2. c4 e5 3. dxe5 d4 4. Nf3 Nc6

```

It yields a generally fun time for White. Tese are, statistically, Black's best moves. However, there seems to be a trap of sorts: `5. g3` is White's most common response but there are 7 games with the *uncommon* Black response of `5. ... Bg4`. From 7 master games, Black wins or draws 5. I'd avoid `g3` :-D

Here's a sample game where White did not. Nathan Birnboim v. Itzhak Veinger, Munich 1987. ECO D09.

```

[fen ""]
1. d4 d5 2. c4 e5 3. dxe5 d4 4. Nf3 Nc6 5. g3 Bg4 6. Bg2 Qd7 7. O-O O-O-O 8.  Qb3 h5 9. h4 f6 10. exf6 gxf6 11. Rd1 Bh3 12. Bh1 Bc5 13. Nc3 Qg4 14. Na4 Bd6  15. Kh2 d3 16. Rxd3 Nge7 17. c5 Bxg3+ 18. fxg3 Bf1 19. Bf4 Bxe2 20. Rxd8+ Rxd8  21. Bg2 Kb8 22. Re1 Rd3 23. Qc4 Rxf3 24. Bxf3 Bxf3 25. Qe6 Qg6 26. Qc4 Bd5 27.  Qc3 Bxa2 28. b3 Qf7 29. Qd2 Bxb3 30. Qd7 Ne5 31. Qd8+ Nc8 32. Ra1 Qc4 33. Bxe5  Qe2+ 34. Kg1 Qxe5 35. Rf1 Qxg3+ 36. Kh1 Qxh4+ 37. Kg2 Bxa4 38. Rxf6 0-1

```

Everything looks normal until move 7, where Black's Queenside castling pretty much declares he's uninterested in a draw. Such games are generally razor-sharp. On move 8, Black announces he's uninterested in a *long* game. He believes White's King's position is weak and he's exploiting it *now*. `9. h4` hurt my face. I had to invoke Stockfish which didn't have a huge problem with (or particularly like) `8. ... h5 9. h4`. Stockfish didn't have a problem with `12. Bh1`, either. At move 12 White is ahead a little, but Black has chances. Black's playing aggressively but White solves the problems. Stockfish didn't care for `13. ... Qg4` and considered `15. ... d3` a blunder. If I can read the tea leaves, after move 15 Stockfish considers White up by about 2 pawns.

To this point Black has had the initiative and has aggressively posed problems for White. Both players have erred between moves 15-19 but White has increased his advantage to the point he'll probably win.

But a won game is sometimes hard to win! White starts to falter on move 24. Whites 24th, 25th, 26th, 28th, and 29th moves are poor. Black plays well and erases White's advantage completely. It's a horse race again!

So where are we? on move 30, Black has a glaring back-rank weakness but the Knight on `e7` protects `c8`. White's Kingside pawns are slightly better but the backward `g` pawn negates most of the advantage. White's Queenside pawns dropped like flies. Black's 3-to-1 advantage will eventually be worth a piece. Black's Knights aren't aggressively placed but defend very well. Black's queen can rampage and is otherwise uncontained. White's Knight is looking silly there on the rim but his Queen and Rook are well placed. White's biggest problem is his exposed King. While I couldn't foresee the position when he played `9. h4`, I can't say I am surprised. Black is always going to have a 'get out of jail free' card as long as Queens are on the board. White will be better off if that Black Bishop is removed; the Bishop's mobility is devastating with the White king being so exposed.

White loses the game on move 32. Ra1 is a terrible blunder. Here's what Stockfish recommended instead.

```

[fen "1knQ4/ppp2q2/5p2/2P1n2p/N4B1P/1b4P1/7K/4R3 w - - 4 32"]

```

( I can't get the replayer to work: Here are the moves: `1. Nb6 axb6 2. cxb6 cxb6 3. Qh8 Bc4 4. Rxe5 fxe5 5. Qxe5+ Ka7 6. Qb8+ Ka6` )

We see White start a combination that culminates in the destruction of the Black King's safety. White counters his biggest problem by sticking Black with the same problem.

Back to the main line, the ghastly `32. Ra1` sort of hits `a7` while defending the misplaced Knight. White loses tempos bigtime. Black's `32. ... Qc4` is menacing in itself, but now we see the Knight on `e5` is a monster. If it makes it to `g4`, it's going to be lights-out for White. `f3` a good square too. White kills the Knight but then gets a demonstration of a *Zwischenzug* \- an in-between move. Instead of the knee-jerk recapture with the `f` pawn, Black checks with the Queen, snags the Bishop, and forks the Rook and g-pawn.
Black threatens something like `1. ... Qxg3+ 2. Kf1 Bc4#` When White prevents this with `Rf1`, Black scoops up both reminaing Kingside pawns then scoops up the Knight on `a4`. Brutal.

---

Backing waaaay up now, I'd choose a different move that `5. g3`.

Instead, I'd consider the prophylactic (and most common White move behind `5. g3`) `5. a3` Black's best response is `5. ... Nge7`. 18 games featuring other responses yielded -0- wins for black. Ouch. This seems to be one of those cases where both players have chances but one side (in this case Black) has to play *much* better to achieve a good result.

The first 10 moves are straight out of theory; there was no deviation in the master games.

I'll present the last games to amuse us - I have no more time for running the engine or providing b-player analysis.

This is an ECO D08. White is Anatoly Karpov and Black is Rustam Kasimdzhanov - two heavyweights, to be sure. This encounter is from the Keres Memorial at Tallinn on January 8th, 2006.

```

[fen ""]
1. d4 d5 2. c4 e5 3. dxe5 d4 4. Nf3 Nc6 5. a3 Nge7 6. b4 Ng6 7. Bb2 a5 8. b5  Ncxe5 9. Qxd4 Qxd4 10. Bxd4 Nxc4 11. Nfd2 Nd6 12. a4 Nf5 13. Bc3 Bc5 14. e3 O-O  15. Nb3 Bb6 16. N1d2 Nd6 17. Nc4 Nxc4 18. Bxc4 Re8 19. O-O Ne5 20. Be2 Be6 21.  Nxa5 Rxa5 22. Bxe5 Bb3 23. Bf4 Rxa4 24. Rxa4 Bxa4 25. Ra1 Bb3 26. Bf3 Bc4 27.  Rb1 Bd3 28. Rb3 Be4 29. Bxe4 Rxe4 30. Rc3 Rb4 1/2-1/2

```

The game is blown wide open. If Karpov can stand it, you can too.

Here are two more samples with the same 10 first moves. The viewer may not show it but White wins both.

Fernando Peralta v Manuel Perez Candelario, Nov. 8th, 2006.

```

[fen ""]
1. d4 d5 2. c4 e5 3. dxe5 d4 4. Nf3 Nc6 5. a3 Nge7 6. b4 Ng6 7. Bb2 a5 8. b5  Ncxe5 9. Qxd4 Qxd4 10. Bxd4 Nxc4 11. e3 Nd6 12. Nbd2 Bd7 13. a4 f6 14. Be2 Ne7  15. O-O Nd5 16. Rfc1 c6 17. bxc6 Bxc6 18. Bc5 Nf5 19. Nb3 Nb4 20. Bb6 Bd7 21.  Bxa5 Nc6 22. Bb6 Be6 23. Nc5 Bxc5 24. Bxc5 Kf7 25. Rcb1 Na5 26. e4 Ne7 27. Nd4  Bd7 28. Nb5 Ng6 29. Nd6+ Ke6 30. Bg4+ 1-0

```

And one more. Mihajlo Stojanovic v. Branko Tadic, March 12th, 2007.

```

[fen ""]
1. d4 d5 2. c4 e5 3. dxe5 d4 4. Nf3 Nc6 5. a3 Nge7 6. b4 Ng6 7. Bb2 a5 8. b5  Ncxe5 9. Qxd4 Qxd4 10. Bxd4 Nxc4 11. e3 Nd6 12. Nbd2 Bd7 13. a4 f6 14. Bd3 Bf5  15. Be2 Ne4 16. g4 Nxd2 17. gxf5 Nb3 18. fxg6 Nxa1 19. Bxa1 Bb4+ 20. Kf1 hxg6  21. Kg2 O-O-O 22. Rc1 Kb8 23. Nd4 Rh4 24. Bd3 Bd6 25. h3 Rdh8 26. Bxg6 Rxh3 27.  Nf3 R3h6 28. Bd3 g5 29. Rc4 Rd8 30. Bf5 Re8 31. Bc3 b6 32. Rg4 Reh8 33. Re4 Rf8  34. Nd4 Rh2+ 35. Kf3 Kb7 36. Ne6 g4+ 37. Rxg4 Rh5 38. Be4+ Ka7 39. Nxf8 f5 40.  Rg8 1-0

```

# Answer
> 9 votes
A flexible and well respected approach is to take the e-pawn, put knights on f3 and d2, and follow up with a king side fianchetto. You will find this article very useful on how to deal with it. Patience is the key. Don't try to "refute" it as soon as you can. It is a perfectly playable opening for black. But play prophylactic moves that develop and reduced black's counterplay, and you will be fine.

# Answer
> 9 votes
**Declining the gambit**

Not really. White is at an advantage accepting, and will fall to a disadvantage if the gambit is declined.

**Maintaining a closed position**

Well, considering White aggressively played `1. d4 .. 2. c4` there is no closing this position up. The rest of the game will be open.

**Maybe `3. e3`**

This option is so-so.

```
[FEN ""]
1. d4 d5 2. c4 e5 3. e3 Bb4+ 4. Nc3 Ne7 5. dxe5 Nbc6 6. Nf3

```

**Blunting black's counterattack**

Yes. This is the route you should travel and it will bear fruit. Be aware of Black's *main* attack which is exploiting `e3` when a bishop check `Bb4+` is available. That can be very deadly and is known as the Lasker Trap. **Do not allow Black to check on `Bb4` while `dxe3` is available.** Accept the advantage, fiancetto the king side, and move into a positional advantage, fully defended, and ahead in development:

```
[FEN ""]
1. d4 d5 2. c4 e5 3. dxe5 d4 4. Nf3 Nc6 5. g3 Nge7 6. Bg2 Ng6 7. Bg5 Qd7 8. O-O Ngxe5 9. Nxe5 Nxe5 10. Nd2 h6 11. Bf4 Ng6 12. Nb3 Nxf4 13. gxf4 c5 14. e3 Be7 15. exd4 cxd4 16. Qxd4

```

# Answer
> 0 votes
g3 is a good move.

a3 also a good 'prophylactic' move....whatever that means....(what would a Trojan Horse be?) for white,generally speaking, but I prefer not to play it, as it wastes time.

But g3 is correct in my very limited estimation!!

# Answer
> 0 votes
Nf3 first isn't it? Or not....? For me, Nf3 first

I was just messing about on Stockfish with the variation...

1. d4 d5
2. c4 e5
3. dxe5 d4
4. Nf3 Nc6
5. g3 Bg4
6. Bg2 Qd7
7. O‑O O‑O‑O
8. Nbd2 Nge7
9. c5 Ng6
10. b4 a6
11. Qb3 Be6
12. Qa3

---
Tags: opening, theory, gambits, queens-gambit
---


# Question
Title: Could you help me to find which game this is?
When I was a kid, I remember reading a newspaper article about a chess game. The article was written as if the writer was one of the players. It was a pretty surprising game and it looked as if it was a total domination. The article was like this:

> I was just picking up the free pieces. I was so confident that I was dominating the board. I saw him writing "resign" in the notation paper. To make him more desperate, I took his rook with my bishop. I was waiting for him to flick his king. Then suddenly, he scratched the word "resign" and has written "Re8" instead. Then it hit me. I was losing.

The article I have read was a long time ago therefore I might be wrong about Re8.

Is this a famous game? If you know which game this is, can you help me?

# Answer
> 16 votes
https://www.chess.com/article/view/how-to-avoid-blunders-part-two

> In one of his books GM Alexander Kotov even coined a term "Dizziness due to success" which describes Chigorin's blunder that we just witnessed pretty accurately. Kotov even tells his own story. He was playing a game and achieved a completely winning position. His opponent lost any interest in his game, and mostly watched the games of other players. Moreover, he wrote "White resigned" on his score sheet, folded it and put it in his pocket. Kotov knew that his opponent was just waiting for a good moment to stop the clock and concede the defeat. Fortunately, such a moment was very close and Kotov took the White Bishop on f7. Guess what happened after that.
>
> When Kotov's opponent executed his winning move, he took his score sheet out of his pocket, crossed out "White resigned" and it was Black who had to resign the game. It doesn't even matter to me if the White player did this little trick (with folding his score sheet) on purpose or he genuinely thought that the game was over. The point is once you start thinking that the game is over and your opponent is about to resign, blunders are almost unavoidable!

# Answer
> 9 votes
Sorry it is not an answer to the original question. It is supposed to be a comment to StudetT's answer - definitely correct one - but is too long to fit the comment format. Just a bit of chess history.

**Dizziness due to success** was not coined by Kotov.

It is a title a Pravda editorial, signed by Stalin (I have no idea who actually wrote it), published in March 2nd 1930. The phrase marked a beginning of a next phase of Stalin's purges and was probably the first notable example of newspeak.

By the time Kotov used it in *Thinking Like a Grandmaster* (in 1969 I suppose) it was already deeply rooted in the Russian language, and had mostly ironical (or even Orwellian) connotation.

The first time it was used in the chess context (again as far as I am aware of) was an article by Veniamin Blumenfeld (1884-1947), see Dvoretzkij, from the bottom of page 108. I cannot find when the article was originally published, but it was surely after the editorial: Blumenfeld quotes the game Sergeev-Grigoriev of 1932.

---
Tags: master-games, sacrifice, famous-games
---


title: Non-losing strategy for white

text:
# Question
Title: Non-losing strategy for white
If you modify chess so that white gets to make one extra move within the first 10 moves, is it possible to show there is a non-losing strategy for white?

# Answer
> 6 votes
Student T gives an explicit answer, but you can also view it from a game-theoretical perspective.

Suppose normal chess is a draw (or a win for black). Then, white can play 1. Ng1-f3 and Nf3-g1, effectively becoming black and the rest of the game is normal, so it is a draw (or a win for white).

Suppose normal chess is a win for white. This will almost certainly involve moving a pawn two steps from its initial position within the first 10 moves, or moving a bishop, queen, rook or king. You can use your extra move to perform this move in two steps, e.g. e2-e3-e4 or Bf1-d3-e2.

In any case, White will not lose the game.

# Answer
> 3 votes
Yes. 1.e4, then move the white Queen out to f3|g4|h5. Prepare for Qxf7+ then Qxe8 or Qxd7+ then Qxe8. Now white wins because the black king is gone.

---
Tags: strategy, theory, chess-variants
---


# Question
Title: 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?

# Answer
> 5 votes
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.

---
Tags: opening, database
---


title: Which books are suited for 1500 elo?

text:
# Question
Title: Which books are suited for 1500 elo?
I currently have 1500 Elo on chess.com and recently I feel like I reached a bottleneck, it seems that no matter what, it is difficult to go higher.

Considering that I want to reach 1800 which books are recommended?

Probably I am facing strategic problems, for example I can develop the rooks, by connecting them, then double them on a column, but then I don't know anymore what to do. Sometimes I can reach the 7th rank, but other times it seems simply pointless to double them.

Similarly, I develop other pieces, I can reach good positions, but still I don't know how to fully utilize them at full extent

Last, I am still having problems when the enemy launch it pawns at me on my castled side and I have to use my paws to defend.

# Answer
> 5 votes
I would recommend the Yusupov-Series, in your case the first three books (orange), called Fundamentals.

There are a lot of books out there that you would profit from reading, but the Yusupov books are more of a trainings course and I believe that you generally get out of a book in (terms of Elo) what you put into it (in terms of effort).

Doing these exercises will give you actual practical abilities instead of just illusions of understanding.

# Answer
> 2 votes
Getting to 1500 ELO means that you've grasped much about the tactical nature of the game - when you have a strong position you can win. Now you're ready to push on into more abstract territory; how can I make my position stronger despite not seeing how to win right now?

For this there is nothing better than Jeremy Silman's "How to Reassess Your Chess." He guides you through a series of different "imbalances" that a chess position can have. With this comes the ability to plan, judge whether exchanges are beneficial and find subtle ways just to improve when there is no clear way to win.

1500 ELO and improving is an incredibly exciting place to be. I have no doubt that you'll be recommending this book to similarly ranked friends for many years to come!

# Answer
> 1 votes
Anything by Chernev is good at 1500 - Logical Chess Move by Move is his most famous book. Has an explanation after each move.

Teach yourself better chess by Hartston is also good (and cheap). Bridges the gap between beginner and master.

---
Tags: books
---


# Question
Title: How does a USA chess player get invited to a chess tournament like the China-USA Chess Summit (2013)?
How does a USA player get invited to such a tournament if it were to happen again? If I were to make a goal to play such a tournament what steps would I have to take? Just curious on how the registration process works since tournaments involving more than one nation seem to be closed compared to regular tournaments in the US. It would be really helpful if someone could explain how you register or get invited for either country involved.

# Answer
> 4 votes
The participants, at least on the US side, were roughly the level of players that are generally expected to play in the US Championship, although the top few players (at the time, Nakamura, Kamsky and Onischuk for the men and Krush, Zatonskih for the women) did not take part. That would imply that if you're male, you would need to be a solid grandmaster, and if you're female, probably 2200 FIDE at least. My hypothesis is that the USCF went down the list of US ratings from the top until they found enough willing players to fill their roster.

Becoming a GM is extremely difficult and you need more motivation than being able to play in a single tournament. If you're female, 2200 FIDE (about) is easier but will still require years of effort depending on your current skill level.

---
Tags: tournament
---


title: Does ...Rxe3+ work for Black?

text:
# Question
Title: Does ...Rxe3+ work for Black?
In the position below, does `...Rxe3+` sacrifice work for Black? I need concrete lines, that prove your claims, I can not satisfy myself with some rough evaluation.

Thank you. Regards.

```
[Title "Black to move"]
[StartFlipped "0"]
[fen "2krr3/ppp2ppp/3b1n2/8/6P1/2NPB3/PPP1KPq1/R2Q2R1 b - - 0 1"]

1...Rxe3+

```

# Answer
> 8 votes
This looks like a 'no engines' question, otherwise ALNS would have just used Stockfish. Be afraid, B-player analysis is happening!

```

[FEN "2krr3/ppp2ppp/3b1n2/8/6P1/2NPB3/PPP1KPq1/R2Q2R1 b - - 0 1"]

1...Rxe3 2.Kxe3 Re8+ 3.Kd2 Bf4

```

```

[FEN "2krr3/ppp2ppp/3b1n2/8/6P1/2NPB3/PPP1KPq1/R2Q2R1 b - - 0 1"]

1...Rxe3 2.Kxe3 Re8+ 3.Ne4 Rxe4+ 4.dxe4 Qxe4+ 5.Kd2 Bf4+ 6.Kc3 Nd5+ 7.Kb3 Qb4#

```

```

[FEN "2krr3/ppp2ppp/3b1n2/8/6P1/2NPB3/PPP1KPq1/R2Q2R1 b - - 0 1"]

1... Rxe3 2.Kxe3 Re8+ 3.Ne4 Rxe4+ 4.Kd2 Bf4+ 5.Kc3 Nd5+ 6.Kb3 Qxf2 7.dxe4 Qb6+ 8.Kc4 Ne3+

```

```

[Title "White survives, sort of"]
[FEN "2krr3/ppp2ppp/3b1n2/8/6P1/2NPB3/PPP1KPq1/R2Q2R1 b - - 0 1"]

1... Rxe3 2.Kxe3 Re8+ 3.Ne4 Rxe4+ 4.Kd2 Bf4+ 5.Kc3 Nd5+ 6.Kb3 Qxf2 7.a3 Qb6+ 8.Ka2 Be5 9.c3 Nxc3+ 10.bxc3 Bxc3 11.Rg2 Qe6+ 12.Qb3 Re2+ 13.Rxe2 Qxe2+ 14.Kb1 Qxd3+ {After this Black is able to trade the pieces and have a deadly pawn majority on both sides of the board, and an extra piece. Further play was very computery so I didn't post it.}

```

```

[Title "Stockfish calls it a win"]
[FEN "2krr3/ppp2ppp/3b1n2/8/6P1/2NPB3/PPP1KPq1/R2Q2R1 b - - 0 1"]

 1... Rxe3+ 2.Kxe3 Re8+ 3.Ne4 Rxe4+ 4.Kd2 Nd5 {Here's the killer. The knight closes the luft on c3} 5.dxe4 Qxf2+ 6.Qe2 (6.Kc1 Bf4+ 7.Kb1 Nc3+ 8.bxc3 Qb6#) Bf4+ {Now Black strips the Queen's defender} 7.Kd1 Ne3+ 8.Kd2 Nxg4+ 9.Kc3 Qxe2 10.Rge1 Bd2+ 11.Kd4 Qf2+ 12.Kd5 c6+ 13.Kc4 Ne5+ 14.Kb3 Qb6+ 15.Ka3 Qb4#
```

---
Tags: analysis
---


title: Fischer playing Greenblatt in 1977

text:
# Question
Title: Fischer playing Greenblatt in 1977
Is there any information, apart from the three games, regarding Fischer playing the Greenblatt computer in 1977? Wasn't Fischer living in seclusion at that time? How did someone manage to have Fischer play? Is there any photo of the event?

# Answer
**TL;DR**: In summary, the sources I've found of the match reference Fischer himself.

Fischer sent the game scores himself:

> Rumors constantly reappear about the possibility of his playing again or making public appearances, but the only published games that we know of since 1972 were against the Greenblatt program, **and they were submitted by Bobby himself and published in the Computer Chess Newsletter**. Bobby sent the scores of three games in which he massacred the computer. In his comments on the games, Bobby noted that the computer was very weak and that he could give it great odds and still beat it.

Source: csmonitor.com

The match was held in Cambridge, MA:

> In 1977, unbeaten chess champion Bobby Fischer played three games in Cambridge, Massachusetts against Greenblatt's computer program, and Fischer won all of them

Source: Wikipedia, referencing Bobby Fischer's biography

I haven't found contemporary images or information on how the match was arranged.
> 4 votes

---
Tags: engines, fischer
---


title: Extreme effort to keep a pawn backward

text:
# Question
Title: Extreme effort to keep a pawn backward
I'm currently studying chess strategy, and I can across an example of backward pawn exploitation that I do not understand. The book I'm reading suggests 1... Rd5 to keep the d4 pawn backward. Doesn't that put the rook into a precarious position to be attacked by 2. Bxd5? Why is it so valuable to keep the d4 pawn backward?

For reference, I'm looking at the example on pg. 236 of Silman's "Reassess Your Chess", 4th edition.

```
[Title "Black to move"]
[StartFlipped "1"]
[fen "3r1rk1/1pb2pp1/p1p1pq1p/2P2b2/3PBP2/PPB5/2Q3PP/4RRK1 b KQkq - 0 0"]

1...Rd5

```

# Answer
In this case, the pawn on d4 is not just a target. It's also restricting white's bishop on c3. For that reason, it's very important that black not allow white to sacrifice this pawn by playing `d4-d5` when white would have very good chances to hold.

Black would like to trade off light square bishops and then put a rook on d5. The immediate `1...Bxe4 2.Qxe4 Rd5` fails tactically because white can play `3.f5!` with decent counterplay on the kingside. Additionally, at least one pair of major pieces will be traded off after white plays `f5`, and generally speaking the side with the isolated pawn or backwards pawn wants to trade off major pieces.

After `1...Rd5!`, white cannot take on d5 because the Be4 is pinned to the white queen. Black will play `2...Bxe4` next move and then a move like g6 in order to stop white's f5 advance. Black will be much better - nearly winning - because black can slowly bring the dark square bishop around to f6 or g7 where it will attack the d4 pawn. Black will also double rooks on the d file. White, in the meantime, has no constructive plans that don't create new weaknesses.
> 9 votes

# Answer
The move 2. Bxd5 would lose to Bxc2, taking the queen. If the queen moves, Black can always take bishop e4 anyway. But there is nothing wrong with 1... Bxe4 and only then 2... Rd5.

In any case, the position is about equal - White has some space advantage to compensate for the backward pawn and bad bishop. A backward pawn is harder to protect, and in this case it severely hampers the mobility of the bishop on c3.
> 1 votes

---
Tags: pawns, exchange
---


# Question
Title: Why is this a threefold repetition draw?
I'm relatively new, so sorry if this is obvious. Recently played a game on my phone chess app where the option popped up that I could claim a threefold repetition draw. I hadn't known about this rule. Researching I found this: https://en.wikipedia.org/wiki/Threefold\_repetition#The\_rule

But I can't figure out the three positions that were exactly the same at any point. Can someone point it out to me? I can find three where I (as black) repeat positions moving around my rook at the end, but the white pieces seem to be in different places when this happens, specifically the white king.

Thanks for the help! Below is a link to the game analysis, plus the full pgn notation.

Game upload:

http://en.lichess.org/CYvX2RlR

Full notes:

```
[fen ""]
1. d4 d5
2. Nc3 Nf6
3. Bg5 Bf5
4. Bxf6 exf6
5. e3 a6
6. Bd3 Qd7
7. e4 dxe4
8. Bxe4 c6
9. Bxf5 Qxf5
10. d5 Bc5
11. Qe2+ Qe5
12. Qxe5+ fxe5
13. O-O-O Bxf2
14. d6 Nd7
15. Nf3 O-O
16. Rhf1 Be3+
17. Kb1 Rad8
18. Rfe1 Bf4
19. g3 Bh6
20. Nxe5 Nxe5
21. Rxe5 Rd7
22. Re7 Rfd8
23. Rxd7 Rxd7
24. g4 Bf4
25. Ne4 b6
26. c4 Bxh2
27. Re1 Rd8
28. Rd1 Rd7
29. g5 Bf4
30. Kc2 h5
31. gxh6 Bxh6
32. b4 Bf4
33. c5 b5
34. Rg1 Kf8
35. Rg4 Be5
36. Kd3 f5
37. Rg5 fxe4+
38. Kxe4 Bf6
39. Rf5 Rf7
40. Rf3 Ke8
41. Rh3 Rf8
42. Ra3 g5
43. Rxa6 Bd8
44. Ke5 Kd7
45. Ra7+ Kc8
46. Ke6 Rf6+
47. Ke5 g4
48. Ra8+ Kd7
49. Ra7+ Kc8
50. Ra8+ Kd7
51. Ra7+ Ke8
52. Rg7 Rf2
53. Rxg4 Rxa2
54. Ke6 Re2+
55. Kf5 Kf7
56. Rg3 Rf2+
57. Ke4 Rb2
58. Ke5 Bf6+
59. Kf5 Rf2+
60. Ke4 Rh2
61. Ra3 Ke6
62. Ra6 Rh4+
63. Kd3 Kd5
64. Ra7 Rxb4
65. Rf7 Rd4+
66. Ke2 Rf4
67. d7 Ke6
68. Rxf6+ Rxf6
69. d8=Q b4
70. Qd6+ Kf5
71. Qb8 Re6+
72. Kd3 Re4
73. Qc8+ Re6
74. Kc4 b3
75. Kxb3 Ke5
76. Kc4 Kf6
77. Kd4 Kf7
78. Kc4 Re4+
79. Kb3 Re6
80. Ka4 Kf6
81. Ka5

```

# Answer
> 3 votes
The position after 47.… g4, 49.… Kc8 could have been repeated with 51.… Kc8.

Because you have to claim threefold repetition before you make the move 51.…Kc8, producing the same position on the board, this would have been a sensible point for a popup dialog.

# Answer
> 2 votes
Upon review, it looks to me as though you had found a bug in the program.

No threefold repetition even seems possible on the *next* move, much less during the moves already made.

---
Tags: rules, threefold-repetition
---