Working with UCI protocol (coding) I'm currently writing small application for a chess interested friend. The application is supposed to automatically annotate his chess games. When giving the engine a position to analyze, and a depth (or time) for doing it, I'm looking to get the following info in return:
1. The best three (or any other given number) moves and their scores in centipawns.
2. An evaluation of a given move (ie his move).
I would really appreciate if someone could tell me how to accomplish this. I guess my lack of knowledge about chess and chess engines makes it harder for me than it actually is.

/Tom

Let's use Stockfish to find out the moves for this position

[fen "N7/P3pk1p/3p2p1/r4p2/8/4b2B/4P1KP/1R6 w - - 0 34"]

The FEN string is: "N7/P3pk1p/3p2p1/r4p2/8/4b2B/4P1KP/1R6 w - - 0 34". You should copy-and-paste my commands to experience yourself.

Load the position by "position fen ..." and then use "d" to print the position. Please note that "d" is a Stockfish-only command.

tedwong@:~$ stockfish
Stockfish 6 64 by Tord Romstad, Marco Costalba and Joona Kiiski
position fen N7/P3pk1p/3p2p1/r4p2/8/4b2B/4P1KP/1R6 w - - 0 34
d

 +---+---+---+---+---+---+---+---+
 | N |   |   |   |   |   |   |   |
 +---+---+---+---+---+---+---+---+
 | P |   |   |   | p | k |   | p |
 +---+---+---+---+---+---+---+---+
 |   |   |   | p |   |   | p |   |
 +---+---+---+---+---+---+---+---+
 | r |   |   |   |   | p |   |   |
 +---+---+---+---+---+---+---+---+
 |   |   |   |   |   |   |   |   |
 +---+---+---+---+---+---+---+---+
 |   |   |   |   | b |   |   | B |
 +---+---+---+---+---+---+---+---+
 |   |   |   |   | P |   | K | P |
 +---+---+---+---+---+---+---+---+
 |   | R |   |   |   |   |   |   |
 +---+---+---+---+---+---+---+---+

Fen: N7/P3pk1p/3p2p1/r4p2/8/4b2B/4P1KP/1R6 w - - 0 34
Key: 4E025494EA4A7523
Checkers:

Ask the engine to think for 30s and set the number of principal variations to 3.

setoption name MultiPV value 3
go movetime 30000

You'll see a bunch of engine outputs. In particular, you should something like:

info depth 5 seldepth 5 multipv 1 score cp -5 nodes 1540 nps 54 tbhits 0 time 28098 pv a8b6 e3b6 b1b6 a5a7 e2e3
info depth 5 seldepth 5 multipv 2 score cp -8 nodes 1540 nps 54 tbhits 0 time 28098 pv a8c7 e3a7 c7b5 h7h6 b5a7
info depth 4 seldepth 5 multipv 3 score cp -10 nodes 1540 nps 54 tbhits 0 time 28098 pv g2f3 a5a7 a8b6 a7a3
info depth 5 currmove g2f3 currmovenumber 3
info nodes 1618 time 30049
bestmove a8b6 ponder e3b6

Here, Stockfish gives three possible lines: Nb6, Nc7 and Kf3. The lines are sorted in terms of the advantage for the side to move.

Let's check what if your friend blunders a rook by Ra1... We expect Stockfish to report ...Rxa1 with a winning advantage for Black. I use http://analysis.cpuchess.com to make the move and get a new FEN.

[fen "N7/P3pk1p/3p2p1/r4p2/8/4b2B/4P1KP/R7 b - - 1 34"]

The new FEN is: "N7/P3pk1p/3p2p1/r4p2/8/4b2B/4P1KP/R7 b - - 1 34"

position fen "N7/P3pk1p/3p2p1/r4p2/8/4b2B/4P1KP/R7 b - - 1 34"
go move time 30000

You should see something like:

info depth 25 seldepth 38 multipv 1 score cp 692 nodes 34732679 nps 1391812 tbhits 0 time 24955 pv a5a1 a8c7 e3a7 g2g3 a1a3 g3g2 a3a5 e2e4 a7b8 c7d5 f5e4 d5c3 d6d5 h3c8 b8e5 c3d1 a5a2 g2f1 e5h2 c8b7 e7e6 d1e3 a2b2 b7a8 b2b5 f1f2 h2f4 e3d1 b5c5 a8b7 c5c2 f2e1 f7f6
info depth 25 seldepth 38 multipv 2 score cp 62 nodes 34732679 nps 1391812 tbhits 0 time 24955 pv a5a7 a1a7 e3a7 g2f1 d6d5 h3g2 e7e6 h2h3 f7e7 a8c7 a7b6 c7a6 e7d6 a6b4 b6d4 b4c2 d4c5 f1e1 g6g5 g2f3 d6e5 e2e3 f5f4 e1e2 f4e3 c2e3
info depth 24 seldepth 38 multipv 3 score cp -480 nodes 34732679 nps 1391812 tbhits 0 time 24955 pv e3a7 a1a5 a7d4 a5a4 d4e3 a8c7 e3b6 c7d5 b6c5 e2e4 e7e6 d5c7 f7f6 a4a6 f6e5 e4f5 e6f5 g2g3 c5d4 h3f1 h7h6 c7e8 d4c5 a6a5 e5e6 e8c7 e6d7 c7d5 c5d4 g3f3 d4e5 f1b5 d7e6 d5f4 e6f7 a5a8
bestmove a5a1 ponder a8c7

As can you can see the evaluation drops to "cp 692". It was "cp -5" before our move. Therefore the move Ra1 must have been a gross blunder.

Please read the UCI specification for more details.

Your job will be:

Connect an engine to your favourite programming language. You can do it by inter-process communication. There are lots of examples on Google.
Issue UCI commands like how I did.
Parse the commands. You might want to use like a string tokeniser.
Make a move (like how I did with Ra1) to get an evaluation of the move.


Examples of harmony? Recently my chess tutor used a word which in hindsight is very interesting: harmony. He mentioned I should not just develop my pieces in the opening, but develop them harmoniously. Since then, I've noticed this word pop up again and again in various books. At the time, I took it to mean "make sure they are defending each other and working toward a common and well-defined goal", but I didn't really press for clarification.

Of course, in our next lesson, I'm going to ask him about this, but in the interim, I am hoping you can give your favorite examples of harmonious positions/development, as well as non-harmonious positions/development, including why they are harmonious/non-harmonious. In particular, is my above understanding of harmony correct or is it sometimes more subtle than that?

Admittedly, it's hard to make general abstract statements of any kind about chess (e.g. to say what "harmonious play" means) as it is a highly complex and concrete game. So everything said about it must be taken with some grain of salt, and with that in mind, here are some thoughts that will hopefully help you:

Let's draw an analogy with music: (-> used for synonym here)

harmony -> consonance -> unison of notes

Somewhat similarly in chess this sequence translates into:

harmony -> consistency -> synergy of pieces

Consistency: "Having a bad plan is better than having none" by Yasser Seirawan (I'm paraphrasing). This quote really captures the essence: you need to have a strategy planned out which gives your play a sense of direction, otherwise your pieces would be moving around purposelessly all over the board which ultimately leads to redundancies (lost tempi), self-induced weaknesses, low value pieces (non-optimally developed), and so on. So always try to play with a plan in mind, as far fetched as it may seem, and make your decisions in consistence with that plan.

Now to clarify what strategy entails here, one would have to put it into context, but in general it goes without saying that it takes into account not only what you plan to achieve but also what your opponent is aiming for, so it's always adaptive. A strategy/plan in the opening and middlegames could be anything, for instance:

Establishing a minor piece on a certain square - e.g. knights on permanent posts.
A queen-side, central or king-side pawn expansion - e.g. sharp Sicilian type of positions
Forcing the trade of a bad piece - e.g. the caged c8 bishop in many queen's pawn games
Pawn breaks: plans to open up the game by undermining/challenging an advanced pawn (chain) - e.g. e5 - c5 type of breaks in many queen's pawn games again
Gaining control over an open file or diagonal - e.g. being a tempo up in doubling your rooks and claiming the open file.
Enabling a certain piece - e.g. fianchetto'ed bishops.
the list goes on.

Synergy: or more simply coordination, means how to collectively coordinate your pieces towards achieving your planned strategy, after all chess is a team sport among your pieces. Given a target in mind, having a good coordination means you're enabling the right pieces efficiently (minimal tempi investment) while countering your opponent's preventive pieces of that plan. Slightly unlike strategizing, achieving a good coordination requires concrete (calculating actual lines) and tactical (using all the resources in the position) assessment of the position at hand.

So synergizing your pieces in accordance to a plan/strategy can be labelled as harmonious play. Harmony is precisely what opening theory provides us: openings revolve around very clear ideas (take any opening: Sicilian, Benko gambit, Nimzo, ...) and in a way provide also the recipes for how to achieve those ideas (concrete lines and side-lines). So learning from them you can form a mindset for how to develop your pieces harmoniously.

Now some examples: (in what follows I'll be mainly focusing on a schematic analysis of the ideas, as opposed to a purely concrete one).

Example #1: Sicilian Najdorf, in this example white's main plan revolves around (i) establishing a minor piece, preferably a knight, on the permanently (cannot be challenged by pawns) weakened d5 square (ii) while not allowing black to expand on the queen-side. Once can argue that (ii) is in fact a side-plan that actually enables (i), as you will see later in the game.
Coordination: To achieve (i) we need to remove the defenders of that square (d5), namely the f6 knight and the potential e6 bishop, develop or re-route the knights so they can simultaneously eye d5. The two defenders will have to be negated by our bishops (Bg5 for f6 and Bc4 for Be6). (ii) on the other hand, is achieved by a timely a4-a5 push, to permanently stop black from establishing a pawn on b5 or a knight on b6, nor even allow them to semi-open the b-file  with b6. (Diagrams annotated with additional remarks):

 [title "M. Vachier-Lagrave vs I. Nepomniachtchi 1-0, Sinquefield Cup 2017"]
 [fen "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1"]

 1. e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 a6 6.Be2 e5 {First critical moment: Black has finally made their intentions clear with a very committal e5 - all e6 or g6 variations are irrelevant now} 7.Nf3 {Instead of Nb3 because white wants to be able to re-route to d5 either via c4-e3 or c4-b6} Be7 8.Bg5 {developing the bishop to immediately challenge the f6 knight guarding the d5 square} Nbd7 9.a4 {Stopping b5} O-O 10.Nd2 {Re-routing to c4 while waiting for the d7 knight to move before capturing on f6, we don't want to allow a knight recapture.} Nc5 11.Bxf6 Bxf6 12.Nc4 Be7 13.a5 {Completely stopping any b5 or b6 ideas with a5 and Nc4} Rb8 14.Nb6 Nd7 15.Ncd5 {with a5 critically re-enforcing b6, a knight on b6 and d5, black has no way of establishing a knight on either f6 or b6} Nxb6 16.Nxb6 Be6 {last resort to stop Nd5} 17.Bc4 {immediately challenged - notice the coordination between white's pieces up to this point, almost perfect!} Qc7 {Freeing d8 square to re-route the dark-squared bishop in order to capture the knight before landing on d5.} 18.Qd3 Bd8 19.c3 Qc6 {preparing Bxb6, note black doesn't mind recapturing with the f-pawn on e6 as that would provide black with some well needed light-square control} 20.Bd5 {important intermediate move: first pushing the queen away from the defense of d6 pawn, then capturing on e6 to force black to re-capture with the queen. These are all the tactical/concrete aspects we were talking about earlier.} Qe8 21.Bxe6 Qxe6 22.Nd5 {Mission accomplished: you can argue that white has already won the main strategic battle of the game.} f5 {an important pawn break: to primarily undermine the defense of d5 while also creating play on the king-side} 23.O-O Rc8 24.Rfd1 fxe4 25.Qxe4 Qf5 26.Qe2 Kh8 27.c4 {the knight in untouchable. In what follows we have a beautiful conversion of this positional advantage into a win.} Bh4 28.g3 Bg5 29.Ra3 Rce8 30.h4 Bd8 31.b4 Qg6 32.h5 Qf5 33.Ne3 Qe6 34.Rad3 Be7 35.Nd5 Bd8 36.Rf3 Rxf3 37.Qxf3 Kg8 38.Kg2 e4 39.Qe2 Qe5 40.Ne3 Bg5 41.Rd5 Qf6 42.Nf5 Re6 43.c5 dxc5 44.Qc4 Qf7 45.Rxc5 h6 46.Rc8+ Kh7 47.g4 Re7 48.Qd4 Re6 49.Qd5 g6 50.hxg6+ Kxg6 51.Rf8 Qxf8 52.Qxe6+ 1-0

Example #2: Catalan by Kramnik, a lot of the ideas in the Catalan revolve mainly around the g2 fianchetto'ed bishop, that is, we want to on the one hand, prevent black from finding ways to exchange our g2 bishop, and on the other hand, further enable the bishop by challenging the g2-b7 diagonal. The g2 bishop similar to the g7 bishop for black in the Benko gambit, is what gives us a sense of direction in our play. Now let's watch Kramnik in action:

 [Title "Vladimir Kramnik vs Anish Giri 2014 (1-0)"]
 [fen ""]

 1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.Nc3 e6 5.g3 dxc4 6.Bg2 b5 7.Ne5 {Adding pressure on c6} a6 {There's a tactical idea involved here: white would be doing themselves a dis-favour if they took on c6 here, as 8.Nxc6 Qb6 9.Nxb8 Bb7 would actually enable black to quickly challenge the g2 bishop forcing an undesired e4, while having got rid of the c6 weakness} 8.O-O Bb7 9.b3 {challenging the light-square control, in order to prepare Nd3. Note that white's queen-side pawns are often absorbed in challenging black's queen-side pawn expansion in these types of positions} cxb3 10.axb3 Be7 11.Bb2 O-O 12.Qc2 Nfd7 13.Nd3 Qb6 14.Ne4 {both knights coordinating towards the control of c5 square: as long as we control c5 the c6 weakness stands for black, a clear target for white} a5 15.Ndc5 Bc8 16.Qc3 b4 17.Qe3 Na6 18.Rfc1 {immediately re-enforce c5 after black's renewed challenge.} Nc7 19.Nxd7 Bxd7 20.Nc5 Be8 {let's step back and look at the position: Both semi-open a and c files contain black back-pawns, the c5 control has completely disabled black from getting rid of the c6 weakness, with a passive bishop on e8 black has no means of challenging white's g2 bishop,... we can safely say: white has won the main strategic battle of the game.} 21.Ra2 Qb5 22.Qd3 {The rest is Kramnik's beautiful conversion of this clear positional advantage} Qxd3 23.Nxd3 Nd5 24.Ne5 Ra6 25.Bf1 Nc3 26.Bxc3 bxc3 27.Rxc3 c5 28.dxc5 Bf6 29.f4 Bb5 30.Bg2 Ra7 31.c6 Be7 32.Be4 f6 33.Nf3 Rd8 34.e3 e5 35.fxe5 fxe5 36.Rc1 a4 37.bxa4


Free, simple chess program for beginners I can't play chess very well, and want a computer game to play against. I've tried two so far - Chessbase (Fritz 5.32) and Crafty Chess. Both had the same problem that even on the lowest difficulty setting, the computer trashed me.

I'm running Windows XP. Here are my criteria:

100% Free (no nagware)
Lightweight: loads quickly, small filesize (say under 15 Mb)
Not system intensive. I don't need or want a 3d board.
Multiple difficulty levels, the lowest one being comparable to someone who's just been told what the legal moves are, and the highest one being... good. Good enough that I won't have to switch to a more advanced program for a while.

If it could have a nice clean interface without clutter everywhere, like the current move list and advanced AI options and what not - which might be great for advanced players but I have no need for - that would be nice.

If you know of a program like this for other operating systems, go ahead and post them for future readers... but I'm on XP.

Download Babaschess, sign up for the Free Internet Chess Server (FICS) and start playing unrated games against real people. :)


What is the significance of openings? I am a beginner in chess and don't understand the concept of openings at all. To me they appear to be just moving one of the eight pawns or one of the two knights. But wherever I see there is talk about opening games and they have many names like Sicilian Defence, King's Indian Gambit, etc. What is the need to differentiate them with so many names, for after all as I mentioned earlier, it is going to be one of the eight pawns or one of the two knights?

INTRODUCTION AND RELEVANT INFORMATION:

  I am a beginner in chess and don't understand the concept of openings
  at all. To me they appear to be just moving one of the eight pawns or
  one of the two knights.

This is the root of the problem, and the reason why you have asked the question-it is the consequence of your ignorance.

POINT #1:

You must understand that human being plays the game, and human beings have likes and dislikes. Some of us prefer sharp and fast struggle, and some of us like slow and safe maneuvering, and so on...

POINT #2:

You do not appreciate your turn to move, but in chess, this is very important to master.
You see, when it is your turn to move, you have a choice, and this is really important.
This is the moment where you have a say, and you can change the course of the game to your like ( see the POINT #1 ).

This is one of many things that differentiates master from novice-master enforces the pace of the game, while beginner complies/plays any move without careful thinking, which results in him/her lamenting later " How did I get into such a horrible position??? How did I blundered a bishop?? " and so on. In chess, this is called tempo.

You must comprehend that you too are the factor in the game, and that this is collision of characters.You must comprehend that not only you play "against pieces" you play against another human being.

Your approach to the game is faulty, because you " dissect " the game, and probably in your opinion there are 3 parts of the game:

Opening
Middlegame
Endgame

This type of division is old and inefficient.

In order to understand my answer, and other answers provided from different members, you must change the approach.

You open the game in order to develop pieces the best way to carry out your middlegame plan, and your middlegame plan is based on the possible events that might take place in the endgame ( chess rules can help you in this, serving as a beacon to follow, but true mastery comes when you learn when to break them-that comes with experience ) .

This is the approach that is the most efficient, in my opinion.

ANSWER:

  What is the significance of openings?

Openings help you to determine what type of opponent is playing against you-does he/she like fast, open battle, or slow and maneuvering one, does he/she aim for endgame or mating attack and so on...

Opening allows you to choose how to tackle those opponents, and enforce them your style of play.

A small example:

Let us say your opponent opened with 1.e4 and you do not want open battle.Let us assume that you like slow maneuvering battle, and feel comfortable playing endgames. In that case you would like to answer with a move that doesn't force early conflict but allows you to choose the moment when the big battle will take place. You could play 1. ...c6 and be confident that the further development of events will be suitable to you.

But what if you want the opposite? What if you want a fast, sharp, open battle?
Then you could reply with 1. ...Nf6 for example. Notice the change of the rhythm:
In the first example White had a choice after Black's 1st move, but now is forced to play with the e-pawn or to defend it.This small example fantastically illustrates POINT#2 from the introduction ( in fact, the whole opening does, and is called Alekhine's defence ).

In open positions, you do not get static solidity and you have to adapt to the changes in the position "on the fly".
In closed ones, your position is solid but you usually need a lot of effort to generate counterplay.

To resume:
Opening helps you to reach the positions that suit your stile ( style being your character/skill level... ) and their knowledge helps you to prepare the position to transpose into middlegame that also corresponds to your style, as well.
Knowing the opening means that you will not be defeated in first 10 to 25 moves, and gives you certainty that you will have an enjoyable game with equal chances to win.

  What is the need to differentiate them with so many names, for after all as I mentioned earlier, it is going to be one of the eight pawns or one of the two knights?

The classification of the openings allows you to find the opening you wish to study, and the openings you wish to prepare against.

These are generally classified as follows:
A ( unsorted ), B ( semi-open games ), C ( open-games ), D ( closed games ), E ( semi-closed games ).

There is an overwhelming amount of moves/move orders and so on, to study and so many openings with the same general idea, but different implementation so you might want to look at them all and choose the one that suits you the best.

Another small example to illustrate this:
Let us say that you are slow, endgame oriented player.
You need an opening that gives you solidity in the beginning, and an advantage in the endgame.
Let us say that you want to prepare against 1.e4.
You could choose 1. ...c6 or 1. ...e6, but although they have the same concept ( repel White's initiative and smash him in the endgame ), there are differences:
The first choice offers harder time to generate counter play, but you have no weak pieces, yet the other one generates counter play easily at the expense of the weak piece ( the light squared bishop ).
Two openings with the same idea, but the implementation of it is drastically different,and only one of them will suit to you.
After you pick one of them, another question arises: Which particular variation in that opening suits your style?
Now comes the strength of POINT #2 into play!
Let us say you have picked 1. ...e6, and let us start "studying" it for a while:
1. e4 e6
2. d4 d5
3. Nc3

A "sharp, fast paced, open battle" player would choose 3. ...Bb4 here forcing the matters, while the slow, solid one could try with 3. ...dxe4, for example, simplifying and slowing things down a bit.

Let us assume that you decided that the second option suits your style and you wish to study that.

But how will you find material for this opening?

Well, first you search the name of the opening-it is French defense.
Then you search its general code-it is C.
Then you search the variation you are interested in-it is 10.
So the opening code is C10.
And now you can find online materials/books on the opening you want to play.

Sorry for the lengthy post, hopefully it will help you.
If you have further questions ask, and I shall answer them as soon as I can.
Best regards.


When playing a computer opponent what situations should I create to give myself a better chance of winning? Normally when I play against a computer I try to avoid any positions where I feel the knowledge-base of the computer would give it an advantage. For example I find computers very strong in typical protracted opening sequences and in endgames.

I seem to fare best against strong computer opponents when I play more positional, "by the gut" chess than when I attempt to apply a more strategic and tactical game plan.

I am wondering if this is something other people have experienced; if there is a practical basis for this belief and what type of chess situations have proved fruitful for them when playing against a digital opponent.

Interesting question, but it's a little bit hard to answer generally.  Any engine has its own quirks, but I'll try to give a few general hints and things to consider.

First, any modern engine on sufficiently fast hardware is going to wipe you off the board.  Even top GM's lose to engines with odds. 1  However, most engines have the hardest time in closed positions where long-term strategy is more important than tactics on any given move.  Games that are very closed (think classical KID lines) are won or lost based on chess understanding, and engines still don't truly understand chess.

One very interesting thing, however, is that some engines actually are vulnerable in extremely tactical games.  Most notably, engines are not always as good as humans when one side has a large attack.  Engines are notoriously bad at overestimating defensive resources and going into a line that is losing for the defender.  However, there is absolutely no margin for error in this case since a single misstep means the loss of the game.  This method (i.e. attacking the computer's king), is a very easy way to win against slightly weaker engines - for example the ones built into Windows and Macs (also the chess games on international flights, but those are really awful...).

To finish, probably the only way to have good chances against a strong machine are to memorize the moves ahead of time.  This might sound fantastic, but it's already been done.  The point is that the engine will spit out the exact same moves every game (under identical conditions), so it's possible to find a hole in the engine's repertoire and steer the game into this gap.

1. Rybka has played many odds matches - most notably against IM Meyer, GM Ehlvest, and GM Milov (who actually won the match!).


e3 vs e4 in 1.d4 openings In some openings, like Nimzo-Indian, the usual e-pawn move is e3, while in openings like the KID, White can play e4.
Is there some guidelines to know when you can play e2-e4?

In the Nimzo-Indian, Black's entire opening strategy is built around restricting the e4 push. 1... Nf6 stops it immediately. 2... e6 prepares 3... Bb4, which stops it again. Black's takeaway from the opening is that white is generally only able to achieve e4 by making some concession.

In the King's Indian, Black makes no attempt to stop the e4 push other than 1... Nf6 which is of course only a temporary delay. 2... g6 and 3... Bg7 are both aimed at d4.

So, you can tell when you can play e4 by looking at the idea of Black's moves.


Best books on middlegame strategy? What are the best works trying to systematically summarize all middlegame themes and strategies: e.g. space advantage, pawn structures, exposed king, minority attack, isolated pawn, hanging pawns, etc. etc. I know of Euwe and Kramer two volumes work about the middlegame, but are there others, too? (PS no, I am not talking about Bronstein's Zurich 1953. Although it's a great book, I am speaking of a different kind of work.)

The two books by John Watson about strategy. These themes are considered from a historical viewpoint usually in contrast to the way they are presented in textbooks. Even if you find a favorite textbook then later you should verify everything against John Watson's books because he always gives counterarguments and counterexamples to what is established as the usual course material.


What to study after someone stopped playing for years? I stopped playing for 2 years and then I had some periods where I played and studied chess, but never for more than a few months in a row. I have an ELO of 1900.

After these 2 years without playing, I noticed that I take way more time to think during my games (did I lose confidence?), sometimes hesitating for a long time between two good moves that should not matter that much (like "should I play Bd3 or Bc4 in the opening?", or "should I take with the c or e pawn?").
I also noticed that I forgot some opening lines (which I think is completely normal) and some endgames too.
I almost always end up with time trouble, even though I read guides about time management.

My question is: what should I study to get back to my level before I stopped playing?

I used to do a 15 min tactics on ChessTempo and Lichess, but I stopped because in a game you never know when there's a combination and the puzzles on ChessTempo became so difficult that I often ended up playing the moves I thought was best because I could not find the combination of +10 moves in my allocated time frame.
Now, I do the exercises from Practical Chess Exercises which are more similar to what you have to do during an actual game. I also do the very easy exercises in Ct-Art 6 because I think it takes me too much time to find these in a real game.
I also started to review my endgames and I do endgames exercises on Chessable.

For the openings, I tried to switch to new openings, but it did not go well, probably because I needed more time to learn them.
So, what I do now is I review my old openings.
I'm not sure I should review my openings though, because I'm pretty sure I don't lose my games in the opening.

Is there anything else I should do?
Should I stop review my openings and focus on other weaknesses?

Edit: By the way, I did play a few tournaments (not as much as before I stopped playing, but still) and in a club since I stopped playing.

Having had experience with this exact problem myself a while back, there is only one advice that I can give: play as much as possible! If the time management issues you're describing are a new occurrence they are most likely due to you being rusty, and they should be corrected by regular tournament play. It takes time to reinstate the trust you had in your own in-game judgement after a long period of inactivity, but it will most likely come back if you keep on playing regularly.

As a final note: studying chess theory is never a bad idea if you're looking to improve, but don't expect it to fix your problems with time management.


How can I increase the search ply depth of my minimax function for my chess engine? I have programmed a minimax function with alpha-beta pruning for a chess engine I am building. However, it is very slow and I cannot analyze to a deeper depth as it would take too much time. I believe this is because my alpha-beta pruning isn't efficient.

For example, for my engine to analyze a position to a depth of 4-ply (white moves, black moves, white moves, black moves), it takes 11.5 seconds to analyze about thirty thousand positions (taken from a middlegame chess example). Without the alpha-beta pruning, there would be about 100 000 positions, so the pruning removes 70%. Is this inefficient or is my computer just slow? And another piece of information (I don't know if this would affect the speed): the only analysis I am using is static analysis, so I count up how many points each side has in material as well as giving them a bonus of + or - 100 if there is checkmate.

From SmallChess's suggestion I have already implemented

no deepcopy
no shuffling
checked generator

Below is my minimax function:

pose = 0
def minimax(board, depth, maximizing_player, alpha, beta): #table is board
    global pose
    children = list(board.legal_moves) #find all possible moves from certain position

    if depth == 0 or board.is_game_over(): #don't go deeper if game over/depth ended
        return calc_eval(board), None #calc-eval finds piece-values on board and adds them up. e.g. two pawns would be 2 points

    if maximizing_player == True:
        best_value = -float("Inf")
    else:
        best_value = float("Inf")

    for child in children:
        pose += 1
        board.push(child) #copy board and change it by moving the child move
        new_val = minimax(board, depth - 1, not maximizing_player, alpha, beta)[0] #recursively find value
        board.pop()
        if maximizing_player == True and new_val > best_value:
            best_value = new_val
            best_move = child
            alpha = max(alpha, best_value)
        if maximizing_player == False and new_val < best_value:
            best_value = new_val
            best_move = child
            beta = min(beta, best_value)
        if alpha > beta:
            break

    return best_value, best_move

Build a cache. You're exposing yourself to endless transposition.
Please don't shuffle your moves. I don't have the numbers but I doubt randomly shuffle all your lists can be quick. It's O(n). I fail to see how it can address your repetition anyway.
Double check your generator. Source code is not here, so I have no idea
I don't know what exactly your table is, but deep copying can never be quick. Each deep copy would need to allocate some memory space. Don't copy, you need to make a move and then undo the move. In chess programming, we don't make a deep copy of the board at every node, we make a move and then undo it.
Double check how exactly your chess board makes a move, is that efficient?


Can White defend and possibly win? [FEN "1nkr2nr/pppp2pp/2b2p2/3q4/3P4/1NQ5/P1P2PPP/R1B1R1K1 w KQkq - 0 1"]

Can White possibly win in this position and avoid a queen mate on g2?

Avoid queen mating on g2 is easy:

f3, Qg3, Qh3+ are decent options
Re4, Kf1 also prevent immediate mate but are not good

Winning this position is objectively speaking impossible. Black is up a piece and white does not have sufficient compensation for it. Most players would resign if playing somebody of 1800 strength or even less.
If black is a beginner and/or short on time white could try to continue the game. The usual plan in lost positions with material down is to keep the position as complicated as possible and to avoid trades. You want to activate your pieces and start to attack something, specifically the enemy king.
In this regard one possible plan could be:

Qg3 (protects g2, attacks g7 and eyes c7), also makes space for the c pawn to move (clearance),
Bf4 develops the bishop a tempo by double-attacking c7. Also makes space for a rook to move to c1 (clearance)
Rac1 and 4. c4 or even immediately 3. c4 with the idea that after Qxc4 you play Rac1 and have a half-open file with attacking chances on the king

Once you get in c4 you can follow up with d5 which limits the range of the only active black minor piece.
Of course black also makes moves in-between and could spoil this plan.
The following example continuation is not best play, but about the best white could hope for for the next couple of moves:
[FEN "1nkr2nr/ppp3pp/2b2p2/3q4/3P4/1NQ5/P1P2PPP/R1B1R1K1 w - - 0 1"]

1. Qg3 g6 2. Bf4 Na6 3. Rac1 Kb8 4. c4 Qf7
5. d5 Ba4 6. Nd4

The final position is still lost for white, but at least white got the more active pieces and more space than black. There could be some attacking potential along the b file as well, now that the bishop left c6.


Where does the black king stand in this specific position? [FEN "7r/pppppKpP/6P1/8/8/8/n7/8 w - - 0 1"]

Assume that the following position was reached in a legal game of chess. In the last 5 moves, no pawn has moved and no pieces were captured. The Black king is invisible – on which square does it stand?

The black king must be on c8.
The white king reached g8 through g6 and h7 before the white pawns arrived on g6-h7. A white knight took the Bc8 from b6; the black queen was also taken by a knight. The black king remained en e8, and the black rook on a8, until a few moves ago.
The last moves were for instance:
[Title "Invisible Black King solution"]
[FEN "r3k1K1/ppppp1pP/6P1/8/8/8/8/2n5 w q - 0 1"]

1. Kh8 Na2 2. Kg8 Nc1 3. Kh8 Na2 4. Kg8 O-O-O+
5. Kf7 Rh8


Can the bishops and knights triumph over the queen? I heard that two bishops and two knights have good winning chances against the queen according to the 7-man tablebases. Unfortunately, even the pawnless 7-man tablebases are not available online. So, I am wondering if this special position is won for white.

[FEN "3qk3/8/8/8/8/8/8/1NB1KBN1 w - - 0 1"]
[TITLE "White to move and win?"]

Houdini's Shootout at Level 21 Ply :

[Event "Stellung ausspielen (Houdini15aw32, 21p)"]
[White "Neue Partie"]
[Black "Houdini 1.5a w32"]
[Result "1-0"]
[FEN "3qk3/8/8/8/8/8/8/1NB1KBN1 w - - 0 0"]

1. Nf3 Qa5+ 2. Nbd2 Qb4 3. Ne5 Qc3 4. Nd3 Qf6 5. Bb2 Qh4+ 6. Ke2 Qh2+ 7. Nf2

Qc7 8. Bd4 Kf8 9. Nfe4 Ke7 10. Ke3 Kd7 11. Bc4 Ke7 12. Bd5 Qd7 13. Nf6 Qc7 14.

Nf3 Qc1+ 15. Ke4 Qc8 16. Ng5 Qc2+ 17. Ke5 Qc7+ 18. Kf5 Qc2+ 19. Nge4 Qd1 20.

Bc5+ Kd8 21. Ke6 Qe1 22. Bb6+ Kc8 23. Ke7 Qe2 24. Kf7 Qf1 25. Nc5 Qf4 26. Bb7+

Kb8 27. Bc6 Qf5 28. Na6+ Kc8 29. Bd7+ Qxd7+ 30. Nxd7 Kxd7 31. Nb4 Kc8 32. Ke6

Kb7 33. Nd5 Ka6 34. Be3 Kb7 35. Kd6 Kb8 36. Kc6 Ka8 37. Nc7+ Kb8 38. Bb6 Kc8

39. Ba7 Kd8 40. Nd5 Ke8 41. Kd6 Kf7 42. Ne7 Kg7 43. Be3 Kf6 44. Bf4 Kf7 45. Bg5

Ke8 46. Nc6 Kf7 47. Ne5+ Ke8 48. Kc6 Kf8 49. Kd7 Kg7 50. Ke7 Kg8 51. Bh6 Kh7

52. Bf8 Kg8 53. Ng4 Kh7 54. Kf7 Kh8 55. Bg7+ Kh7 56. Nf6# 1-0

Theoretically yes, as a practical matter (for humans), no.

What is known is that a pawnless position cannot be won (barring unusual positional circumstances) if one side has an advantage of a bishop or knight, but it can be won if one side has the advantage of a rook (or a queen versus a rook).

The "old" wisdom is that three minor pieces are worth about a queen, so white has the advantage of one minor piece. As a matter of fact, three minor pieces may be worth more than a queen, pushing white's advantage closer to, say, queen versus rook.

The other thing is that with so many pieces and moving parts, White has "coordination" problems. That's why as a practical matter, human beings won't win with this kind of advantage. The advantage of a computer is that it can calculate its way around coordination problems. If the minor piece synergies indeed give the computer an advantage greater than a minor piece, the computer will find a way to bring this extra power to bear; a human being (other than a world champion caliber player), will not.


Is there a terminology for "the worst winning move"? What do people call a move which maintains a winning position but is the worst among all such moves?
For example, h8=N+ is such a move in the following game:
[FEN "8/7P/6k1/8/8/8/B1K5/8 w - - 0 1"]

1. h8=N+

I will not normally play such moves in serious games, but in casual games such moves might be good practice for endgame skills.

The short answer is no.
In 25 years of chess experience I have never heard such a term. There isn't unless there is some definition somewhere in a shady club packed with sadists who love to mate with several knights!


What are the specific setups to avoid perpetual checks(Queen)? I was wondering if there certain setups with pieces, pawns, or both which avoid perpetual checks. I know an important setup is the one below where it's essentially a fortress type of a position for white. Are there any other ways to avoid perpetual checks. The reason I am asking for this is that in endgames I often blunder perpetual.

It would be very helpful if you would post a couple of those games you mentioned that you gave up perpetual check.

I would say, "no", there are no stock positions that are meant to avoid perpetual check (at least I cannot think of any now that I would call "common"). You just have to be careful, and be aware of king safety. Sometimes, you just cannot avoid it either as it is a valid component of defense.

I will say that one common setup in queen endings is the following type of position. White has managed to post the queen very centrally, and it can go either from the h1-a8 diagonal, as it is now, to prevent checks; or as it helps the a-pawn move forward, it can move to the g1-a7 diagonal to defend e3, and help advance the pawn from there. It is critical to note that with rooks on the board, the white king's lack of safety would probably prevent this, keeping a white rook passive on the first, and allow black to setup counterplay against the passer.

 [FEN "8/5pk1/q5p1/P2Q3p/7P/6P1/5PK1/8 w - - 0 0"]

 1. Qd4+ Kh7 2. Qb6 {And the passer moves on}


In which article did Nigel Short retract from having played online vs Fischer? I read a recent tweet by Nigel Short mentioning his retraction, but I can't find it.

I thought it was in New In Chess where he was writing a column for a long time,
but according to chessbase.com it was in Telegraph:
https://en.chessbase.com/post/the-third-coming-of-bobby-fischer-


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

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

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

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

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

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

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

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

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


In the Schliemann defense, who does Schliemann refer to? The Schliemann's Defence or Schliemann–Jaenisch Gambit refers to the moves 1. e4 e5 2. Nf3 Nc6 3. Bb5 f5.

f5 is of course a gambit move by black typically known as the Jaenisch Gambit when white plays the Ruy Lopez scenario. Questions is: Who was Schliemann? Is the name referring to a person or is this some creative term?

According to the section of the Wikipedia page on the Ruy Lopez, it's named after a German lawyer, Adolf Karl Wilhelm Schliemann (1817-1872), although it doesn't say why his name is attached to it.

However, the German Wikipedia page on Adolph Schliemann (English translation), indicates he was a strong master who contributed to the early theory of the line.


Next world chess championship When and where is the next world championship? Also, when is the candidates? Where can I find the important chess tournaments online?

When and where is the next world championship?

It will take place in 2020 at the end of the year. The exact date and location have not been revealed nor decided yet.

  When is the Candidates?

In 2020, the same year as the world championship match. It usually takes place in March, but no official information about it has been released yet.

  Where can I find the important chess tournaments online?

If you are asking about the dates, then there are many sources. The one I use is 2700chess. Scroll down to the "Future Events" section. It lists many scheduled upcoming tournaments as well as the most notable players taking part in each. There is also the Chess.com tournaments calendar.

If you are asking about the broadcasts of the tournaments, then either Chess24 or Chess.com is the right place for you. Personally I use Chess24.


How can a human figure out best move in this position? Why is 12. b4 played by a GM? Why doesn't he just capture the bishop? And how can he forsee so far in the future? Am I missing something?

Maybe before justifying the pawn sacs one should answer more convincingly why taking on c3 would not have pleased White. The answer is the backward pawn on c-file and future pressure against it by rooks from c-file. Black cannot be happier if the Queens get exchanged on c3 as well. So, taking the bishop back on c3 would have yielded nothing for White. b4 is half out of desperation as it is of creativity!

Augment to this the forcing sequence delineated by the other answers here, and you see that b4 is not as much of an abnormal move as it may look initially.


Find a KNP-KQ endgame in which Black loses How do I find a position where Black, on move, cannot save themselves from defeat, having a king and queen against White's king, knight, and pawn? Furthermore, Black is not in check.

[Title "White plays and wins (note the position after 2 Kg6)"]
[FEN "4N2k/8/6PK/q7/8/8/8/8 w - - 0 0"]

1. g7+ Kg8 2. Kg6 Qb6+ 3. Nf6+ Qxf6 4. Kxf6 Kh7 5. Kf7 1-0

If Black stops 3 Nf6# with Qf5(g5,h5)+ then 3 Kxh5 and the Ne8 still holds
the Pg7 so White soon wins.  The bottom edge of the board barely prevents
Black from turning the tables with 2 ... Qa0+.


Tips on The Greek Gift I always have problems in  executing  The Greek Gift. This a position which I got in a recent game :

rn1q1rk1/1b1nbppp/p3p3/1p2P3/3N4/2NB4/PPP1Q1PP/R1B2RK1 w - - 3 13

Even though the Knight is not there on f6 square and can't come here safely, I lost after scarifying the Bishop.

Can someone explain when and when not to use the The Greek Gift and give some tips regarding the same?

The main tips are:

1) A pawn on e5 helps. Not only does it prevent ...Nf6, but it also takes away the f6-square from Black's king once it comes to g6 (via ...Kxh7-...Kg6).

2) The greek gift is usually followed up with Ng5+. So if the g5-square is defended by Black, or if you don't have a knight on f3, this idea won't work. In some cases perhaps you could make do without the knight, such as Qh5+ followed by bringing a rook to the h-file, but in the position you posted that doesn't look feasible. Rf3 is prevented by the b7-bishop, while Rf4-Rh4 runs into ...Bxh4.

3) Assuming that a Ng5 follow up is possible, calculate the position after: Bxh7+ Kxh7 Ng5+ Kg6. This is usually what happens in the greek gift, since Kg8 runs into Qh5 (with Qh7# threatened). In the position after ...Kg6, how will you follow up? If you play Qg4, can ...f5 be met well (perhaps with exf6 or Qg3)?

4) Make sure that if Black answers Ng5+ with Kg8, Qh5 would truly be winning. For example, can the king escape in any way, or can the h7-square be guarded?

5) Do a force count of the kingside - who has a stronger armada of pieces concentrated there? For example, in your diagram the f1-rook is opened on the f-file and can be a great contributor. But again, since there is no Ng5+ follow up, the idea doesn't work.


Is it possible to reach master level without studying theory? Wikipedia page for GM Granda from Peru says:

Julio Granda does not study opening theory. He has said that he has
only read a chess book, the third volume of the General Chess Treaty
of Roberto Grau. Anyway, he admits reading magazines and reviewing the
Informant, which together with his excellent memory and assimilation
capacity, has allowed him to win important tournaments and titles.
Google translation from spanish wikipedia.

Is this possible? Can one become a master without studying theory at all?

Anything is possible.  The real question is how likely are you and most people to do it that way.

And it depends on what you call 'theory'.

I read NO theory. But I read a lot of practical books on openings, tactics, end games, pawn structure, positional play, yada yada.

They claim that an AI program learned to play Go by playing itself.  I do not know anyone humans that have done that.  We might if we lived millions of years but in reality humans can't do it that way.  Most humans learn by seeing how others,  who win doing it, have done it;  and try to improve on that if possible using the basic tools they learned from practical books.


How to keep improving when missing advanced knowledge prevents finding the answer to tactical puzzles I consider myself to be an intermediate player. I understand the tactical motifs well and can solve quite a few tactical puzzles with relative ease. I have also dedicated time at working on end games and can handle the basic ones with major and minor pieces as well as the ones involving pawns decently.
Lately I have been paying a lot of attention at the tactical problems that I get wrong and I have noticed that for the most part, the reason of my mistakes is that I don't know how to correctly evaluate the resulting position correctly to pick the right move.
For example: I don't really have a diagram but the question is more general than specific so, please bear with me. In a recent one I found the correct first move and on the second one I chose to exchange a knight for a rook thinking I would end up with an advantage in quality. That turned out to be a mistake. The right answer was to take a bishop which made the queen to take my knight which was defended. I kept thinking "why on earth would the queen take the knight if it is going to be taken? It makes no sense".
I know that the right answer boils down to the specific position, even when analyzing it with the engine I could see that in this case, by taking the rook the advantage was completely lost and if the other side did not take with the queen, the advantage I had would rise exponentially.
My questions would be, how can I learn this stuff? What kind of sources do I have to look for? What subject should I Google? What kind of books, or better yet, titles can I read so that I can start understanding this?

I think the most important thing to do right now is to clarify exactly what the problem you're having is. From the somewhat vague example you gave I have a suspicion, but I can't be sure. I think that your problem with the tactics is that the way you evaluate the resulting positions from the tactical sequences you calculate is too simplistic, in this case by being over-reliant on the material count while not taking other positional factors into account.
From the way your example is phrased, it seems to me like you can understand that the resulting position from the correct solution is better than the one resulting from your solution when you compare the end positions next to one another. So it might be a case of you knowing that you're solving a tactical problem, and therefore you assume that you're looking for a way to win material, causing you to "tunnel-vision" when solving these tactics exercises.
In this case, the solution to your problem is rather simple in nature: just be aware that finding the best continuation to a problem is not always the same as finding a way to win material, it's all about ending up in the best possible position.
Another potential problem that could be the issue for you is that you stop your calculation too soon; sometimes it's necessary to calculate further than you originally expect to see why a continuation is good or bad, and if this is the case for you (which it could be, judging by your example) then you need to ask yourself why you stopped calculating at the point that you did. Why didn't you notice that you needed to calculate a few moves further? And if you were to calculate further, would you have been able to see what was wrong with your line? In this case, it is vital to be aware of this if you're ever going to fix the issue in the first place, and to appreciate the importance of calculating to the very end of the line, where the position has clarified to the point where it's easy to evaluate directly.
In the end, I seriously doubt that all your problems with these more "advanced" tactics are based in a lack of "advanced knowledge" of positional chess. I think it has more to do with your approach/attitude to calculation might be somewhat misguided and/or overly simplistic. But in the end, this is hard to judge from one vague example, and I might be way off in my assessment of your particular case. In any case I felt that what I've stated here needed to be stated so that you are at least aware of some of the potential pitfalls with tactics that are easy to overlook if you're not aware of them.


What relative point values of pieces do engines use? Humans use:

Pawn = 1
Knight = 3
Bishop = 3
Rook = 5
Queen = 9.5
Bishop pair = +0.5

But I would like to know what relative point values do engines use (preferably strong engines, like Stockfish, Houdini, Rybka, Komodo, ...).

If the point value that the engine assign to the pieces depends on the position of the pieces on the board (for example a White Knight on a1 is only worth 2.6 but on e5 it's worth 3.4), than I would like to know the average point values of the pieces.

Rybka/Komodo/Houdini are not open source and their values aren't readily available, but the current strongest conventional engine, Stockfish, uses these values (lines 182-186):

PawnValueMg   = 128,   PawnValueEg   = 213,
KnightValueMg = 781,   KnightValueEg = 854,
BishopValueMg = 825,   BishopValueEg = 915,
RookValueMg   = 1276,  RookValueEg   = 1380,
QueenValueMg  = 2538,  QueenValueEg  = 2682,

The "Mg" column is value during the mid-game, and the "Eg" column is for the endgame.
As you might guess, these numbers are empirically tuned.


Is it theoretically possible for Carlsen to reach Elo 3000? Magnus Carlsen just reached a rating of 2889.2 today. Considering the way that Elo works, inflation and deflation and relative strength of Carlsen, I was wondering whether it is theoretically possible for him to reach Elo 3000? If so, is it practically possible?1

1. I know my second question is a bit opinion based, but I actually want to know your opinions!

The average Elo rating of the e.g. top 10 players in the world is rising every year. I think that the relative distance between the number one rated player and the other 9 players in the top 10 becomes relevant in this context. This distance can be estimated by subtracting the average of the ratings of the 9 players (ranked 2-10 in the world) from the rating of the top player (today, Carlsen) and dividing this by the rating of the top player.

Increasing this distance is difficult for the top rated player, because every new game played by the top player has a certain amount of risk and uncertainty. I think that Carlsen will have a hard time reaching an Elo rating of 3000 exclusively by increasing the distance to the players ranked 2-10. Yet, if the relative distance stays the same of the following years and the average rating of the top 10 continues to increase, then it is definitely possible for Carlsen to reach Elo 3000. The second ranked player at that moment would probably have around Elo 2950.


Position with the largest material imbalance that is a draw, no matter whose turn it is? I am curious if there is a known position with the largest material imbalance that, no matter who it is to move, the weaker side can hold a draw.

Here's a humorous, uncredited example I found in Lasker's Manual of Chess. However, a search revealed that it was created by Ludwig Meyer in 1886.

[FEN "b2b3R/1np2pp1/1p3k2/n2KN3/p7/5pN1/P1p3p1/2B2rqr w - - 0 1"]

1. Ng4+ Ke7 2. Nf5+ Kd7 3. Ne5+ Kc8 4. Ne7+ Kb8
5. Nd7+ Ka7 6. Nc8+ Ka6 7. Nb8+ Kb5 8. Na7+ Kb4
9. Na6+ Kc3 10. Nb5+ Kd3 11. Nb4+ Ke2 12. Nc3+ Kf2 (12... Ke1 Nd3#)
13. Nd3+ Kg3 14. Ne4+ Kg4 15. Ne5+ Kf5 16. Ng3+ Kf6

A draw by perpetual check, against all odds! Black has all the pieces, White only a few. Every move is forced.


Weakening the kingside with g5 I am having trouble deciding whether a move such like g5 (g4 in case it is White) is worth it or not. I am looking for advice on my particular position and if possible, a general explanation for any other case.
In the position below I was Black:

I actually considered playing g5 during the game because the bishop on h4 is quite annoying as it is pinning my f6 knight.
However, it is hard for me to understand how this move can be good if after 12. ...g5 13. Bxg5 hxg5 14. Nxg5 and that knight and the combo bishop and Queen is very threatening and both exerting pressure on the king.

What is the reason to make such move? Personally, I would go with something like Be7.

Thanks a lot before-handed.

P.S. : The link to the game is 1

https://lichess.org/BBzc4Y46/black 1

In this case it's tactical. d4 looks like a really strong move but the problem is after 12...d4 13. Bxf6 black has to play 13...gxf6 because 13...Qxf6 drops a piece to 14.Ne4.

However, if you play 13...g5 first followed by d4, then d4 trades off the isolated pawn and equalizes for black. Black also has a little bit of an initiative going at that point.

In general, you don't want to move the pawns in front of your king if you don't have to or unless it benefits you (like in this example).

How to deal with pins? Study unpin combinations. There are a lot with sacs on f7/f2 and h7/h2. There are also some where the knight captures like Legal's mate or captures on d4/d5 sometimes winning a piece.

You can also play actively. For example creating a threat with the queen and then moving the knight to a center square or just playing aggressively in general will sometimes make the pin meaningless. You also have to remember an early pin by the queen's bishop is usually bad. For one it leaves the b pawn unprotected but also if you haven't castled on that side he isn't really threatening anything.

Lastly, if the opponent captures and doubles your pawns that's not always bad. For one, that means you have the two bishops and an open g-file which is typically the file right in front of the opponent's king. It depends on the position but it's not uncommon for your opponent to hand you a ferocious attack by capturing the knight.

Just as an example, to illustrate some points, this is a game I see at least once a week in blitz:

1. e4 e5 2. Bc4 d6 3. d4 exd4 4. Nf3 Bg4 5. c3 Nc6 6. Qb3 with a double attack on both b7 and f7. Black has a lot of ways to go wrong in this position and 6...Bxf3 (which leads to 7. Bxf7+, Ke7 or d7 8. Qe6#) is fairly common.


Can one import FENs of positions involving checkmate into Droidfish? I recently copied the following curious position (from this answer) to clipboard, and tried pasting it in Droidfish.
3b1q1q/1N2PRQ1/rR3KBr/B4PP1/2Pk1r1b/1P2P1N1/2P2P2/8 w - - 0 1

However, the situation involved a checkmate and when I tried pasting it, Droidfish displayed an error message (King capture possible).
My question
So can't I load the FEN of any position involving a checkmate in Droidfish?

Apparently the FEN is wrong. In the position it should be black to move next, so in the FEN there should be a "b" instead of "w". The correct FEN would be:

3b1q1q/1N2PRQ1/rR3KBr/B4PP1/2Pk1r1b/1P2P1N1/2P2P2/8 b - -


Why are ratings calculated by tournament instead of by game? When you go to a chess tournament, why is your rating calculated by your tournament performance instead of how most internet chess servers do it? Why don't they adjust the rating by game? What is the advantage.

The way that rating systems work, your most recent results have a greater influence on your rating than your earlier results. So if your rating was adjusted after each game in a tournament, then the games in later rounds would affect your final rating more than the games in the earlier rounds. Most of the time this wouldn't make much sense, as a tournament usually takes place over a fairly short period of time. It makes more sense to adjust the rating just once, after the tournament has finished, with all games counting equally.


Is there any website that allows you to check if a position has been played before? Is there any website that allows you to check if a position has been played before? I want to analyse a game and I want to check if it has been reached before. Any suggestions?

Look up "Chessbase Live Database" on Google and click on the first result. You should be taken to this url:

https://database.chessbase.com/?lang=en

You just enter moves and click the magnifying glass button, causing a list of games played to show up.


Which online chess websites allow you to download their games? I am looking for a list chess websites which allow you to download large numbers of previously played chess games. Currently I have found that lichess allows you to do so.

Are there any other sites?

I do not care whether the game were played by humans or bots, professional or amateurs, time control or anything else.

Chess-db allows you to search their database for a player and download all their games. For instance, if you search for Magnus Carlsen you get to his Chess-db profile page where there is a link which allows you to download all his games in their database. This is very useful for finding and studying the games of famous players or just for finding the games of an opponent so you can try and prepare against them.


Chess engines as similar to A.I Are there any chess engines that can adapt and 'learn' how to play better with an opponent? One with certain system parameters that can be adjusted while playing so the computer can 'respond' better to a human player?

Learning to play better chess by itself is a part of reinforcement machine learning (temporal difference learning). A simple google will give you some academic papers. My recommended papers (that I've read myself):

KnightCap
NeuroChess
Giraffe

While the programs are different. They share the similar idea:

The idea is like this:

Come up with an evaluation function that you think appropriate
Implement a search algorithm (mini-max, nega-max etc)
Initialise the weights in the evaluation function. The weights would be your features
Play a game against itself
Record the result of the game and compute the error.
Apply the following TD-Leaf equation to change the weights

Play more games until you believe your values have converged

The equation updates the weight vector by the gradient, scaled by a constant (learning rate). The errors would be the temporal difference (d(t)) in the equation. They would need to be added for all moves until the end of game, scaled by the distance from t. Please google TD-Leaf if you want to know more.

While there have been some serious attempts at applying the TD-Leaf algorithm, none of which was strong enough to compete with Komodo and Stockfish. I think that's because:

Lack of determination. The authors wrote their TD-Leaf chess engines for their research. Once that was done, they moved on to something else, something much more profitable for them. For example, the NeuroChess program was written by a very well-known AI export. He works for Google and I think Google has more challenging task for him.
Weak search algorithm
Not challenging anymore. A human tuning chess engine can easily defeat the best grandmaster. Why would we waste time and resources to further improve it? Why not spend the money on Go, where the best human player has yet to be beaten?

Some remarks:

While it's possible to train a model from random weights, we don't want to do this because it would lead to extremely long training times. We can give starting values with some human-knowledge, or bootstrapping (read the Giraffe paper for details).


During the Revolutionary and Napoleonic Era, what was the rule for stalemate in France? Wikipedia has a stalemate history section, but for France it only says:

  The forfeiture of Black's turn to move (medieval France) (Murray 1913:464–66) (Davidson 1981:64–65), although other medieval French sources treat stalemate as a draw (Murray 1913:464–66).

Forcing a passed move is a very interesting stalemate rule. It would mean KNNvK could force a checkmate by first forcing stalemate, then Black passes, then White delivers checkmate.

(But not all stalemates necessarily lead to checkmate. There may be some material that can force a stalemate but cannot make a checkmating move right afterwards. An example is black king at d8, white bishop at d7, white king at d6. Black to move is stalemate, but even if he passes a turn, White has no move that can checkmate him. White couldn't force that position alone, of course. It's just an example of stalemate that doesn't lead to checkmate.)

Anyway, the "medieval France" is not qualified in the article. I would guess 1000 - 1600?

I would like to know what was the stalemate rule in France around the Revolutionary and Napoleonic times? 1789 - 1815.

I can only cite Davidson, A short history of chess (Link), again. From chapter 8:

  [...] In Italy, however, from the very beginning, players could not accept stalemate as a victory for anybody. They argued that since no legal move was possible, the game simply stopped. Consequently in medieval Europe four different stalemate rules were simultaneously in effect, and travelling players had to agree in advance as to whether they were playing by the Spanish (victory for White), French (forfeited move for Black), British (victory for Black), or Italian (drawn game) rules. The Italian practice eventually spread throughout the Continent, partly because of the tremendous influence which Italy exercised on all European culture, partly because of the fame of Italian chess players, and partly because the rule seemed inherently logical. By the end of the eighteenth century every part of Europe (except Britain) had agreed that stalemate was a drawn game.

So according to this account, at least by the time of Napoleon stalemate was considered a draw in France.

ADDED: Even better, there is a contemporary source confirming that stalemate was considered a draw. Philidor, Analyse du jeu des échecs, 1777 edition (Link), rule XVI at the very end of the book confirms this:

  [...] En Angleterre, celui dont le roi est pat, gagne la partie; (b) en France, & dans plusieurs autres pays, le pat est un refait.


Studies that have been cooked by computers A study is unlike a regular chess problem. Instead of "mate in 3" (for instance), a study's instructions are something like "White to draw" (for instance). What this means is to find a line of play after which White reaches a position that is known to be a draw. But there is a problem with this notion because computers have shown us that many situations that were "known to be a draw" aren't really (same for theoretical wins).

  Are there any famous studies that have been cooked (solution is not valid) due to a computer showing that the final position did not satisfy the conditions of the study?

(By famous I mean either a classic that appears in many books or a study that won prizes in problem tournaments.)

I don't know how famous it is, but here is a study shown to be incorrect by computers:
 [Title "J. van Reek, 1987. White to play and draw."]
 [FEN "8/5n2/5N2/3K4/8/3p4/Rn6/1k6 w - - 0 1"]

 1. Ra3 d2 2. Rd3 Nxd3 3. Ne4 d1=N! 4. Ke6 Nd8+ (4... Nh6!) 5. Kd7 Nb7 6. Kc6 Na5+ 7. Kb5 Nb3 8. Nc3+ Nxc3+ 9. Kc4 Kc2 1/2-1/2

The intended solution is given in the diagram. It has a very nice stalemate finish.
Unfortunately black can play 4... Nh6!, and according to the tablebases there is a win for black in 39 moves.
So three knights can win against one. Having to play this ending would give me nightmares!


Psychological tricks in chess? Are there any psychological tricks that can be used in chess to throw off an opponent regardless of rating?  It also does not matter if it is the opening, middle, or end game.

By psychological, I really don't mean rude/annoying gestures to upset the opponent, but more tricks or tactics that have more to do with making psychological moves to throw an opponent off and they can be specific instances, for example, a specific move for a specific line that might make the opponent wonder "what is going on here...".

Sometimes when your opponent is in zeitnot (English: "time trouble"), it can make him nervous if you repeat moves a couple of times.

Also when your opponent is in zeitnot, it is a good idea to think on your moves thoroughly and not to try to play as fast as your opponent does. This also applies to when you're in zeitnot; you should at least try to make your opponent play as fast as you do.

I often try to learn rarely used variations to disturb my opponent and make him think with his own brain instead of mindlessly replaying moves from theory.

If I know that my opponent is rather a strategic player, I will try to play very tactical positions against him and to out-calculate him. When my opponent is better at tactics then I'll try to play more closed, maneuvering positions. In other words, when I know my opponent well, I'll try to play positions that he feels least comfortable in.

I've heard of other tricks of questionable taste, and I personally don't think they fall under "fair play" in my understanding of it.

Another thing I always do (though it is hardly psychological), is that I never inform my opponent if he forgot to press his clock. I use his time for analyzing the position, and make my move only after the opponent pressed the clock.


Is 6...Bf5 inferior to 6...Bd6 in the Caro-Kann Tartakower after 6. Bc4? And if so, why? I'm trying out the Tartakower variation of the Caro-Kann.  It begins

[fen ""]
[startply "11"]
[startflipped "0"]

1. e4 c6 2. d4 d5 3. Nc3 dxe4 4. Nxe4 Nf6 5. Nxf6+ exf6 6. Bc4 Bf5 (6... Bd6)

I have not had much success with it thus far.  I lost a recent LiChess game seemingly without much effort from my opponent.  It continued from the above 6. Bc4 Bf5.  It seems for black 6...Bf5 is inferior to 6...Bd6, being played in far fewer master games (and judging from Stockfish's evaluation: +0.6 vs. +0.3), although I'm not sure if this is correct, and I'm not sure why.

Question: Is 6...Bf5 inferior to 6...Bd6 in the Caro-Kann Tartakower after 6. Bc4?  And if so, why?

It is a bit early in the game to be saying that one move is decisively better than another, but there are general principles that can be applied.

One of these is to ask whether you are already sure where certain pieces belong, and if you are sure, put them there at once unless there is some tactical reason not to. In this variation, where Black recaptures on f6 with the e-pawn, he has already conceded a slightly disadvantageous endgame because he cannot create a passed pawn on the K_side, but White can do so on the Q-side. As compensation, Black has achieved mobility for all of his pieces, and can try to use this to bring off an attack with ....Bd6, 0-0, Qc7 and Bg4 that makes any endgame irrelevant.

So Black is fairly sure that his KB belongs on d6. His QB could belong on g4, f5, perhaps e6, or it might stay where it is while Black plays Re8 and Nd7-f8. He might even consider ..f6-f5. So ..Bd6 has the advantage of preserving options for the QB. There is less value in maintaining options for the KB because we already know where we want it.

The possibility of 6...Be6 is dubious. After 7. Bxe6 (or first 7.Qe2) the Pawn on e6 will be a permanent weakness even it gets to e5.


Is this really played by 2200+ players? I came across the following game and was surprised to find that it was played between players with 2200+ ratings:

How do players of level 2200+ lack the very basics of opening principles to play a game like that? In general, how to beat a professional player with only a few moves in a well-prepared opening?

In short, after some investigation, I do not believe that white was a 2200 player is the real answer. First, I found it odd that it says he was exactly 2200. This is the only tournament I can find that he ever played, and it was an Olympiad, which had to be FIDE rated. He was also from Brazil, which was not a strong chess region in the world at that time. It was also at a time that FIDE ratings started at 2200. I strongly suspect that it was used simply because the tournament director had to use it for rating purposes only, and there was no other rating he could use.

That final position has been reached in my database 9 times. The losing move, 3.fe has been played a whopping 37 times, once by a 2149, but mostly by players 1900 and below. These statistics tend to bolster the idea that he was just a weak player, and that was not his real rating.

That is my real answer, but I have other thoughts on the matter if we were to assume that there are Masters, who have lost easily.

I started playing just a few years after that game, and it starts with the fact that it was a VERY different time. There were only books back then to study from, and not everyone had access to a decent library...in third-world countries, especially.

As a Master, who has never relied on opening theory myself, rather just using an understanding of opening pawns structures, I can tell you that it is easy to find yourself in a position that is very unfamiliar to you.

I also agree with DM that 2200 is hardly a professional....even 2400 is not in most cases, but they may earn a living teaching.

Lastly, another problem is that that early in the game, your sense of danger is not as keen. I once played a 2015 player in a team match. Here was that game. I have won a good number of tournament games in under 10 moves.

 [Title "Godin-Cotreau Team Tournament, 1988"]
    [FEN ""]

 1. f4 d5 2. Nf3 Nf6 3. e3 c5 4. Bb5+ Nbd7 5. Ne5 $2 a6 6. Nxd7 axb5 $1 7. Nxf8 $4 Bg4 0-1


what does this move achieve? I was watching the current Carlsen vs Adhiban game and I saw a move that always puzzles me:

5. h3 Bh5

I'd say Carlsen want to unpin the knight, or kick the bishop away. The bishop retreats, while keeping pressure on the same diagonal

6. Be2

This move I don't get. I can imagine that 6.g4 would cause positional trouble on the kingside, so the bishop is moved to e2 in order to break the pin.

But if this is true, then why did Carlsen play 5.h3 in the first place ?

I don't get what does 5.h3 achieve.

Thanks !

I see at least 3 good points to 5. h3:

first and foremost, it puts a question to the Bishop: if Black wants to maintain the pin, he will have to move it to h5, which is more vulnerable and decentralized. Moreover, once the Bishop will be on h5, white squares on the Queenside will become vulnerable, as the Bishop cannot retreat and defend them in one move (just have a look to b7, for example);
once the Bishop is on h5, White can kick it away with g4 if he wants, gaining space and advancing a Pawn with tempo;
now that h3 is in place, h2 becomes a comfortable flight square for the King if White castles Kingside, thus avoiding first rank weaknesses during the endgame.


Does it change anything to play blindfold chess for a "good" chess player? It's been a long time since I wanted to ask this question to a professional player but as I don't know any, I thought maybe this was the right place to ask: Does it change anything to play blindfold chess for a "good" chess player ? How much is the level of play impacted when you play like this? Also I would like to learn to play blindfold, is there any good way to improve this ?
Thank you very much.

GM Alexandra Kosteniuk on a stream today mentioned how her father would encourage her to solve studies and puzzles by visualising the solutions and then say, setting it up on a board and then solving it blindfolded.
So if you're already at a stage where you can look at a puzzle on a screen and work out the solution without moving any pieces, the next step is to solve puzzles taking a glance at the board and then doing it blind.
This will help you in learning to retain the board in your mind, and having a guide like knowing it is a mate in 3 for example, will be a crutch so you can build up performing more complex calculations.
After you have managed this blindfold problem solving, you can then try playing blindfold chess. There are programs that help to train for this - off the top of my head, I know Lucas Chess offers a feature like this.
Even if you never play a blindfolded game against a real opponent, practicing it the right way can help your visualization and memory, thus helping your overall performance in any game.


FIDE Rules On Reading DURING Game Are you allowed to read a book unrelated to chess during a FIDE rated classical tournament game? I myself have done this a few times whilst studying for exams, but was never sure if it was allowed or not. I am 2100 so no one ever mentioned it. I'm hoping someone can post a definite answer.

There are two sections of the FIDE Laws of Chess which are relevant.

11.3.2.1 During a game, a player is forbidden to have any electronic device not specifically approved by the arbiter in the playing venue.

and

11.5 It is forbidden to distract or annoy the opponent in any manner whatsoever. This includes unreasonable claims, unreasonable offers of a draw or the introduction of a source of noise into the playing area

Use of a Kindle or other electronic book is governed by the first. You will have to get the arbiter's permission to read such a device during the game (or even to have it in the playing area) and this is unlikely.
For a traditional book printed on regular paper you just need to do it in such a way that it does not disturb your opponent (i.e. don't rustle the pages, put the book down noisily, etc.) as covered by 11.5. Although you would be well advised to talk to the arbiter first to clear the fact that the book contains no chess related material.
I have seen this done during FIDE rated league matches with no problems but not in large tournaments.


Strategy on castle (short or long) As we know, we usually doing castle to move king to (assumed) safe place.

But when we play short castle or long castle since my chess engine (Houdini) seems to prefer short castle when I play against a strong player and long castle when I play against a weak player.

The side selected for castling is generally related to the openings chosen by the player.  Long castling has the following attributes:

lands a rook on a center file where short castling does not.
takes more time since an additional piece must be moved (the queen).
leaves the pawn on the a-file undefended.

Finally, when the players castle on opposite wings, the game is less likely to be a draw - the opposing pawns can become purely offensive weapons.

Since Houdini is rated probably close to 1800 points higher than I am and because we don't have any specifics, I can't tell you why it's making its castling choice.  But it does not move based upon the weakness of its opponent, per se - it is making moves based upon board position.

You'll might see Houdini castling long if it has time to get the queen off the back row. Or perhaps if it can gain a tempo by castling long and hitting an opponent's piece in the center.


Best current player in the endgame? In one interview, I do not remember when (please if someone knows give the link), Kramnik quoted that the best endgame player is Alexei Shirov... I think this interview was around year 2000. Obviously for anyone to reach the very top level they must be very strong in the endgame. Now, I do not think anyone would support Shirov as the best in endgame because he is not top 20 anymore and the world champion extracts most of his wins in the endgame.

Who is the strongest player in endgame nowadays?

The blatantly obvious answer would be Magnus Carlsen who is also the No.1 player in the world, his ability to squeeze out wins from drawn endings is unsurpassed (with a few exceptions, e.g Andersson and Smyslov). Other than that I would naturally consider Vladimir Kramnik, although it is very hard to draw the lines between the various stages of the game nowadays as most of the top players nowadays are extremely versatile and have a universal style of play.


Is the Sveshnikov Variation a subvariation of the Lasker-Pelikan Variation? Wikipedia says that the Sveshnikov Variation is :

[FEN ""]
1.e4 c5 2.Nf3 Nc6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 e5

While chesstempo says that is the Lasker-Pelikan Variation, and the Sveshnikov is strictly :

[FEN ""]
1.e4 c5 2.Nf3 Nc6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 e5 6.Ndb5 d6 7.Bg5 a6 8.Na3 b5.

There is no central authority for opening names, and the ones used shift over time. So a definite answer to this question isn't possible.

Bad_Bishop quotes Silman's review of "Sicilian Sveshnikov: Move by Move", which is a bit odd as the book itself treats all variations after 5...e5 (see the PDF preview of the book, chapter "Sixth Move Alternatives".

The same is true of "The Sicilian Sveshnikov" by Kotronias (PDF preview).

But these are repertoire books for black; if you play 5...e5 and white wants to, he can basically force 6.Ndb5 d6 7.Bg5 a6 8.Na3 b5 as there are few serious alternatives for black. So if you play the Lasker/Pelikan, you play the Sveshnikov too, and vice versa. It's logical that they want to treat white's alternatives at move 6 too, so that the book is more widely useful. But then, why not call it "The Lasker/Pelikan: Move by Move"?

I think the name "Lasker/Pelikan" is obsolete, at least in English language chess publications. I've never seen it used in any book or periodical or website in at least twenty years, it's always Sveshnikov. You can easily find many books on the Sveshnikov, and I don't know any on the Lasker/Pelikan. Apart from that Silman review, but he has played chess for a long time.

ECO (and thus the Informant) calls it the Lasker/Pelikan, but its codes and their names are set in stone since the 1960s. Those codes and their names have also ended up in many computer files of opening names, but as far as I can see it's not actually used by anybody anymore.

It's just the Sveshnikov.


Websites for creating tournaments with different starting positions I'd like to create tournament for my students where I specify the starting positions.

Which websites allows users to create tournaments with different starting positions?

You can do this

For free

at https://lichess.org. Go to the "Play" tab, and select "Tournaments." Assuming that you have a lichess account, (all they need for that is your e-mail, and they do not spam it) you will see an option to create a tournament. Once you select that option, you will be able to specify the start position in the tournament (this position must be an opening with an ECO code).

If you wish to have only your students playing in the tournament, you can make the tournament private (password required to enter) and send the password to your students.

You can also play a game (not tournament) from any legal position (opening, endgame, middlegame, whatever) via the board editor, which is under the "tools" tab


Which one is more important between endgame studies and tactics? One strong player once told me that you can improve quickly if you focus more on endgame studies than on tactics training. His reasoning was that endgame studies use a few pieces to cover most of the chess rudiments including strategy, tactics, imagination, concrete calculation, awareness, visualization, etc. While tactics on the other hand can lead to speculation over calculation.

My question is, can a player improve quickly by focusing more on solving endgame studies and giving tactics less time?

Endgame studies are a particular form of tactical problem. I think variety is always good here, but, most importantly, since consistency is critical for improvement at chess, I would suggest you to focus on the type of exercise you enjoy most! (You won't train for too long if it's a sacrifice rather than a pleasure.)

I disagree with the "tactics can lead to speculation" part. Quite the opposite, training tactics is what we do to find concrete realizations of our intuitions/speculations. Of course, this means trying to calculate the entire continuation from the starting position, with all the possible consequences of the moves you are thinking about being considered. But this also applies to solving endgame studies, though!

Finally, I'd say that endgame studies seldom cover relevant strategy, and when they do, it's in a very artificial form. Anyway, if we wanted to improve our chess strategy, why not study chess strategy itself?

In conclusion, I think endgame studies can help you improve your tactical skills, but I'd use them as an additional resource rather than the main focus of your training. Tactical puzzles often have the advantage of being closer to positions you can reach in a real game (you are forced to "remove the noise" and find what's the relevant factor that can lead you to a win.) This does not mean that you should disregard the Master's advice, but rather stick to what's useful from it, so: beware of speculation during your tactical training!


For how long can lone bishop stop king, knight and pawn? Recently I found quite surprising evaluations for me, especially in KNPP vs. KB, where the defending side could hold a draw just with waiting moves, not winning one of the pawns immediately. The h+f pawns with bishop holding promotion square is probably one of those theoretically most important and straightforward draws, but I saw many with pawns being on different files with one file gap and even pawns many files away like c+g.

I just wonder if there was some research on this topic and if there could be some rule said when position is drawn and when it is lost, in both KNP vs. (K)B and KNPP vs. KB. It looks like the bishop can stop some pawns almost forever, giving the king enough time to go sightseeing, grab a very distant pawn and return with very little stress to achieve a draw.

The reason why endgames are difficult, despite there being only a few pieces left on the board, is that many positions can only be evaluated by accurate calculation rather than by appealing to any rule. Rueben Fine in Basic Chess Endings says that KNPP vs KB "is in general a fairly simple win. The exceptions come only with a blockade" He then analyses seven examples of marginal cases. One very surprising example is that doubled pawns always win, a rare case of a universal rule. But even then, some accurate moves have to be found.

But some general advice is possible. For the superior side. Make active use of your King. Send him on ahead of the pawns and then escort them through. For the defender, try to keep your bishop on the longer of the two diagonals that control a crucial square. That will give a better chance of having waiting moves available. But always calculate.


How to get stockfish to play a selfmatch without clearing the hash table between games A while ago I asked a question about how to let Stockfish play 10 games with itself for a limited number of moves:

Python script to let stockfish selfplay 10 games from a given position

This question was brilliantly answered by the user Phonon.

Now I would have a followup question. Since the games are starting from the same position, I would like to avoid to clean the hash memory, as I understand Stockfish does every time it starts a new game. Ideally, even the first game should avoid the hash table clearing since I might have analyzed the position before starting the self match and I would like to keep the information saved in the hash memory.

Is there a way to do that?

Thanks in advance.

I would like to keep the information saved in the hash memory. Is
  there a way to do that?

Yes, there is.

Stockfish is open source. So you can examine the code, modify it, recompile and rebuild.

What you need to do is:

Find where Stockfish creates and uses the cache
Modify the code to save the cache to disk when the game finishes
Modify the code to optionally (you won't want to do it for every new game) load the cache from disk for a new game


Ethics of play in the last rounds of a tournament Suppose I'm playing in a small, 6-round tournament. I win the first five rounds, which also guarantees at least a share of 1st regardless of the results of the last round. What are the ethics of play in the last round? Say the opponent comes to the board and offers a draw before making a move. He judges he's not likely to beat me, so a draw is a good result for him. He's of the opinion that since the result doesn't matter to me, I might as well accept. Should I accept? What if the opponent plays a few moves, and offers a draw in a position I assess as better for me, but still has a lot of play left in it? What if the opponent offers a draw in a position in which he is dead lost?

If I take the draw, I insulate myself from a potential blunder. I also guarantee I win the tournament, not just share first. However by not beating my opponent, I give him an undeserved half-point and more prize money, and it's not fair for my opponents in the first five rounds who had to play me when I was incentivized to win.

Is there some kind of convention for this kind of situation?

USCF rule 14B6 states that "it is unethical and unsporting to agree to a draw before a serious contest has begun".

Also, according to USCF rule 20L, manipulating results is not only prohibited, "severe sanctions" are called for, which might even include revocation of the offenders' USCF memberships.

According to rule 20J, even discussing the possible results with your opponent is improper.

You are not, however, required to ignore the crosstable.  There's nothing wrong with taking a draw to ensure a tournament prize - provided you don't collude with your opponent.


Nimzowitsch Defence - 1. e4 Nc6 2. Nf3 variation I was watching a YouTube video which explains the 1. e4 Nc6 2. Nf3 line of the Nimzowitsch Defence. In that video, the presenter was talking as if after 9... Nd4, white did not have any good move.

[FEN "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1"]
[StartPly "18"]

1. e4 Nc6 2. Nf3 f5 3. exf5 d5 4. Nh4 e5 5. Qh5+ g6 6. fxg6 Nf6 7. g7+ Nxh5 8. gxh8=Q Qxh4 9. Qxh7 Nd4 10. Na3

However, I find that 10.Na3 is a better move for white than 10. Qxc7  which was presented in the video. It prevents both 10... Qe4+ and also 10... Nc2+.

Please share your opinions.

White loses if plays Na3, because Black is threatening with mate via Qe4. Black gains access to e4 with Bf5 move.

r1b1kb2/ppp4Q/8/3pp2n/3n3q/8/PPPP1PPP/RNB1KB1R w KQq - 1 10

1. Na3 Bf5 $19 {Black is threatening with Qe4, which leads to mate or tons of material gain} 2. Bb5+ {To clear escaping square f1 for King, with tempo} (2. Qxc7?? Qe4+ 3. Kd1 Bg4 4. f3 Bxf3 5. gxf3 Qxf3 6. Ke1 Qe4 7. Kd1 Be7 {White is defenseless, Bh4 coming}) c6 3. Qxb7 Qe4+ 4. Kf1 cxb5
5. Qxa8+ Kf7 6. Qxa7+ Be7 {White has no defense}


Situations of underpromoting the pawn I recently came across a wonderful article on Chess.com about under promotion of pawns. One of the situations is here:

[FEN "8/8/1KP5/3r4/8/8/8/k7 w - - 0 1"]
[Date "1895.??.??"]
[White "Saavedra, Fernando"]
[Result "1-0"]
[Setup "1"]
[FEN "8/8/1KP5/3r4/8/8/8/k7 w - - 0 1"]
[Plycount "13"]
[Sourcedate "2014.05.08"]

1.c7 Rd6+ 2. Kb5 Rd5+ 3. Kb4 Rd4+ 4. Kb3 Rd3+ 5. Kc2 Rd4

In the above game using Rook instead of Queen for promotion seems to win it for white.

If white is promoted to Queen, then 6.. Rc4+ and Qxc4 is forced which will be a stalemate.

How many other situations can we consider for the under promotion?

Here's my take on this question, since I find the other two answers lacking actual examples.
Knight promotion
In the situation below black has been trying to prevent white from promoting the pawn (white has earlier given up his rook for a black pawn). White manages to promote, but only one of the promotions secures a (tablebase) draw.
[white "Alexander Evdokimov"]
[black "Evgeni Ellinovich Sveshnikov"]
[event "56th Russian Championships, 2003"]
[fen "8/r3KP2/8/4k3/8/8/8/8 w - - 0 1"]

1.Ke8 Ke6 2. f8=N+! {2. ... Ra8+ otherwise} 1/2-1/2

Here, white underpromotes to avoid stalemate.
[white "Iroda Khamrakulova"]
[black "Ekaterina Ubiennykh"]
[event "WJun Women, 2001"]
[fen "6r1/k1P5/P7/1K1R4/8/8/8/8 w - - 0 1"]

1. Rd8 {according to tablebases, Rd7 wins faster} Rxd8 {again, there are slower ways for black to lose} 2. cxd8=N! {stalemate if rook or queen is promoted, a draw if a bishop (wrong corner)} 1-0

In the situation below, white has just played Qg3. Black underpromotes to gain a tempo, as white threatens checkmate and fork rival king and queen.
[white "Zvonimir Mestrovic"]
[black "Svetozar Gligoric"]
[event "Hastings, 1971/72"]
[fen "7k/1p2Npbp/8/2P5/1P1r4/3b2QP/3q1pPK/2RB4 b - - 0 1"]

1. f1=N+! 0-1

In the position below, white underpromotes to deliver a checkmate.
[white "William Strum"]
[black "John McManus"]
[event "Eastern Open, 1997"]
[fen "8/p3R2P/1p4k1/6p1/2rB2KR/P1r5/8/8 w - - 0 1"]

1. h8=N+ 1-0

Last, but not least, a very neat opening trap. Black undepromotes to gain a tempo and subsequently win the white queen.
[fen "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1"]

1. d4 d5 2. c4 e5 3. dxe5 d4 4. e3 Bb4+ 5. Bd2 dxe3 6. Bxb4 exf2+ 7. Ke2 fxg1=N+ 8. Rxg1 Bg4+ 0-1

Rook promotion
Arguably, less spectacular than knight underpromotions. One would promote to a rook in order to avoid a stalemate (otherwise, anything a rook can do, a queen also can). Two examples from endgames below.
[fen "6k1/6P1/5K2/8/8/6P1/8/8 w - - 0 1"]

1. g4 Kh7 2. Kf7 Kh6 3. g8=R! {stalemate in case of queen promotion. Knight promotion would also win, but would take longer} 1-0

.
[fen "4r3/5RPk/5K2/8/8/8/8/8 w - - 0 1"]

1. Rf8 Rxf8 2. gxf8=R {stalemate in case of queen promotion, unable to win if promoting to a minor piece} 1-0

Bishop promotion
These are the rarest of the bunch. Usually would be to avoid a stalemate, or some other extraordinary situations, since otherwise, anything a bishop can do, a queen also can. First, a classic.
[fen "4Q3/Pq4pk/5p1p/5P1K/6PP/8/8/8 w - - 0 1"]

1. a8=B! {promoting to rook or queen runs into Qf7+ and stalemate} 1-0

Another endgame.
[fen "8/8/5b2/8/K7/4N3/kp6/8 w - - 0 1"]

1. Nd1 b1=B! {Nc3+ if promoting to rook or queen - draw} 0-1

Lastly, this amazing position.
[fen "1r5K/6PP/8/8/8/1k4q1/6P1/8 w - - 0 1"]

1. g8=B+! {black must move the king and it is a stalemate} Kb4 (1... Rxg8+ 2. hxg8=Q+ Qxg8+ 3. Kxg8 {and the g2 pawn will inevitably promote - white wins}) 1/2-1/2

Sources for these and many more examples
http://timkr.home.xs4all.nl/chess2/minor.htm
http://www.chessgames.com/perl/chesscollection?cid=1000028


What was the youngest age at which a prodigy could be considered to have been a master? There is a photo of Reshevsky playing at a very young age (like 8) against many adult players but there were no ratings in those days. I assume that a modern GM who got the title at 12 must have been close to master strength at 8 but I am not sure this is true. I wonder in fact if there is some limitation of the human brain that prevents a certain level of play before a certain age in the same way that no child can run a 4 minute mile, etc.

Let's just say a master is someone who crosses the 2200 USCF mark to get a rough idea. In that case, Abhimanyu Mishra and Liran Zhou both crossed the 2200 barrier around 9 years and 3 months. Christopher Yoo did the same thing in just under 10 years. Note that these chess players did not necessarily reach 2200 strength at those ages, it is likely they were weaker than 2200 but from stochasticity, achieved the crossing. Also note that USCF is the federation associated with United States and 2200 USCF corresponds to something like 2100 FIDE.


What are techniques to improve the number of moves thought through in advance? I read somewhere that on average a GM can think up to 10-15 moves ahead in tactical positions.

Is there any specific technique to improve this depth?

Please do not provide a generic answer on how to improve one's game, I am only interested in understanding how to increase depth.

A very common approach is to work backwards. Instead of studying openings first, followed by the middlegame and the endgame, you study endgames first. Once you know some endgame positions, it may be sufficient to calculate only three moves deep in a late middlegame position, because you know that the resulting endgame is won for you.

Let's consider a position were you have a pawn, king and queen vs. your opponent's king and queen. You have the option to exchange queens and leave black's king too far away to stop your passed pawn. It takes you three more moves to promote that pawn and now you know that K + Q vs. K is easily winning, although it may take another 10 moves. Thus, you just saw 14 moves in advance by going from one position (K + Q + P vs. K + Q) to another (K + P vs. K) and then to a won K + Q vs. K endgame.

This is of course a very basic example, but the point is that grandmasters do not really calculate 30 moves ahead. They just know that the given position transforms into another, which leads to a won endgame. The more positions and the more patterns you know, the better you get at calculating. This might help you to improve that skill:

Learn the most basic endgames
Learn essential checkmate patterns
Learn tactical motifs and patterns
Play games and go over them afterwards

Those "shortcuts" should lead to fast improvement. After you did the above things (or while doing so) it might also be a good idea to practice your visualization. Try to say whether a given square is black or white, whether a given position is checkmate or whether a knight can reach some squares within one move. Furthermore, you should always imagine a combination in your head after a game. Try to move the pieces without touching them in reality and try to picture the position after some moves. A nice program to practice visualization is the freeware "Chess Training Tools". You might want to check that out. An interesting website to learn tactics is http://www.chesstactics.org/. It offers many examples and great explanations.


What is the best way to free your queen as soon as possible? We can open games in many ways (any of the pawns or knights) and then go ahead with different strategies. The queen being the most important piece, I would like to get it out in the field without compromising the security of the king and using a minimum number of moves. Which types of opening and/or moves would facilitate this? Also provide any pros and cons to your strategy.

I don't think that getting your queen out early should be your goal in the opening.  Fighting for the center, developing your pieces, and king safety should be your priority.  That said, e-pawn openings are your best bet to open lines for your queen as soon as possible.  Look into the Ruy Lopez:

[FEN ""]
1. e4 e5
2. Nf3 Nc6
3. Bb5 ...


Is this considered checkmate if I touch a piece which can't make a legal move? What if there's a touch move rule, and my knight or bishop is blocking my king, and I touch it. Is that a checkmate? If not, what is it called?

No. The touch-move rule can't force you to make an illegal move, and it is not legal to put yourself in check.

Here's what the FIDE laws of chess say:

  4.5 If none of the pieces touched in accordance with Article 4.3 or
  Article 4.4 can be moved or captured, the player may make any legal
  move


How to play against Nimzo-Larsen attack if White starts with 1.Nf3 I usually go for the setup of Nf6, d5, e6, Be7, O-O, c5, Nc6 but I noticed that the White players are so familiar with these positions, and the winning rate for White according to the database is huge against this line! So I would like some recommendations against the Nimzo-Larsen attack when white starts with Nf3, and then plays b3. I would like a position with clear plans and easy to understand if possible.
Edit: I forgot to mention that I play the Nimzo-Indian and Ragozin defenses with Black. So when White plays d4, or Nf3 on move one, I play Nf6.

What about 1.Nf3 Nf6 2.b3 d5 3.Bb2 Bg4?
Black development plan is very simple, the main line goes like this:
[FEN ""]
1. Nf3 Nf6 2. b3 d5 3. Bb2 Bg4 4. e3 Nbd7
5. Be2 e6 6. O-O Bd6 7. c4 c6 8. d4 O-O 9. Nbd2

In this position, despite white bishop aiming it is own pawn it is still potentially dangerous; therefore, standard e5 or c5 breaks are not usual in this position.
The safest approach for black is try to exchange the dark-squared bishops with 9...Qe7 10. Ne5 Ba3.
Another approach, most intuitive in my opinion, is 9...Ne4 10. Nxe4 dxe4 If white plays 11. Nd2 then after 11. Bxe2 Qxe2. 12...f5 black has play on the king side, the bishop is aiming at h2 and the queen can be brought to h4 or/and rook to h6 via f6. If white plays 11. Ne5 and then 11... Bxe2 12.Qxe2 black could play 12...f6 forcing 13. Nxd7 and here again black can play on the king's side.
It is also common to bring the queen play 9...Qc7 or 9...Qb8 with the aim of controlling the e5 square and preventing Ne5. But I am not very familiar with this plan.
Also, the position you describe can be reached via 1.Nf3 Nf6 2.g3 move order.
[FEN ""]
1. Nf3 Nf6 2. g3 d5 3. Bg2 e6 4. O-O Be7
5. b3 O-O 6. Bb2 c5 7. c4

to avoid it you can go for the same black setup, with the bishop on g4.