Is it possible to improve the Elo rating system like this? Since all chess player’s ratings are between 800 and 2900, why don’t we make a new rating defined like this:

New rating = (Old rating – 800) / 2.2

So that all chess player’s ratings would be between 0 and 999

Or if we would like to be able to easily convert between old and new ratings we could define the new rating like this:

New rating = (Old rating – 1000) / 2

(Though here extremely weak players would have a negative rating.)

My point is that we would have almost the same precision, but we would only need to use 3 digits instead of 4.

I believe the current rating system is bad because a big range of numbers (3000 to 9999) isn’t used.

What do you think? Is there something obvious that I missed or am I really right?

Sure, you could compress the current range like that. The issue, though, is that ELO is not an objective scale with absolute endpoints. It's only a measure of play strength relative to past opponents.

The fact that no current player has an ELO above 2900 does not mean that such ratings are impossible. Until 1990, no one had a rating above 2800. In fact, there's no mathematical upper bound on ELO rating at all: see this question, for example. The "big range of [unused] numbers" is infinite.

So yes, you could compress the ratings--but what do you do when someone achieves ELO 3001 in the uncompressed system? Recompress it with a different scaling factor, and change what everyone's ratings mean? And keep doing this every time someone "breaks" your current system? If the goal is to make ELO simpler to keep track of, this seems rather counterproductive. I suppose you could report log ELO to make it more tenable (also sillier), but the fact remains that there's no mathematical bound, so there's no guarantee that all ELOs will stay within the range you're looking for.

Perhaps the most pertinent question of all is, why? What do you gain from compressing Elo down to three (ish) digits? It diminishes (slightly) your ability to distinguish between players of similar ratings, but what is the upside? Or, why not compress it down to between one and one hundred, or zero and one? It's all the same values; "three digits" is quite arbitrary, and I can't think of any way that it "improves" on the current system.


To what extent is the openness/closedness of positions determined by white? By black? Say I am playing as white and I strongly prefer closed positions while my opponent strongly prefers open positions. To what extent do I have control over this? Will the game more likely end with a closed position or an open position? What are my strategies if I want to keep the position closed?

If I am playing black, does this change the answer to the questions above?

In general White has more freedom of choice due to going first. He can play a move that is slightly suboptimal and still be around equal. But if Black does the same thing, he could quickly find himself in a bad position.

However, it's obviously not always necessary to play dubious moves in order to get the kind of position you want. In general you should play openings that lead to closed/open positions. In the former case 1.d4 makes more sense, and 1.e4 for the latter. As Black, you could meet 1.d4 with something like the Grunfeld if you like open positions, or with the KID if you prefer closed positions. For 1.e4, the French/Caro lead to more closed positions, while the Sicilian has a higher chance of leading to an open position. Of course, these are just examples.


Why are the corner pieces referred to as "rooks" in English? Various sources like those quoted in Wikipedia say that it's a mistake, or old-fashioned, to refer to rooks as "castles".  Why is this, though?  Other languages generally refer to these pieces as "towers" and when the king exchanges places with them, we call it "castling" rather than "rooking".  The pieces look like castles.  The term "rook", on the other hand, seems to come from Persian/Arabic and have a very obscure etymology.  So why is this word preferred?

Some say:

There will probably other theories about the origin of the name "rook" for this chess piece; however here is the one I believe is best.

IN the origins of the game itself, the game was called Chaturanga and it was not exactly the same as modern chess. The piece we call a rook was considered to be a chariot rather than a castle, probably because of the speed with which it moves. The Sanskrit word for chariot was "ratha". In Arabic it is still referred to as a chariot with the name "rukhkh." When the game spread to Europe, the word "rukhkh" sounded like the Italian word "rocco", which meant "tower." Since the two words sounded alike, the Italian word was used but the meaning changed from chariot to tower.

The piece is still thought of as a tower in European translations. Various European countries use their language's word for "tower" rather than their words for "chariot". In Middle English the concept of tower eventually turned into castle since most castles had towers.

Contributors are welcome to add to this answer any other theories about the name; however they should honor the rule against deleting other answers unless they are obviously wrong. Contributors are also reminded of the rules regarding minor edits.

Other explanations (the ones i believe to be true):

The rook was already known in "Chaturanga", but there, this figure was a carriage and was called "rukh". The war carriages have been a part of the old Indian army until the 5th century. At the time the game came to Arabia the name did not change but the portrayal was simplified. In Europe the English name "rook" remind us to the descent.

But how has the figure changed from a war carriage to a rook?

By the year 1527 Vida, bishop of Albay, published a poem about a chess game between "Apollo" and "Mercury". The rooks were fortifications on the back of an elephant. The European chess players took over the description. Finally they left out the elephant for the normal use.

Notes, I told you what others have said, what you're going to read now is my theory

I am from an Arabic country, Lebanon, and we don't call the bishop "Al Fil", like some website say, at least in my country we don't, maybe some other arabic country did, not us, and we still play Chaturanga (but i don't). We call it Chatarange, it's a French name, since France was the mandate for Lebanon long time ago.

Anyway lets talk about the pieces which is interesting

king = king
queen = queen
knight = horse
rook = castle, yes we call it castle, and it makes sense to castle for
us, we don't rook :)
Bishop = minister, and also makes sense, the Arabs who
played Chess were Muslims you know :) Why European call it Bishop? I
can think of 3 reasons:

Because the bishops were so powerful and involved in political life. Because Christian armies relied on them during the wars, they were the one who blessed a war (Remember the crusaders and the Pop?). And lastly, because they contributed so much to the game (Ruy Lopez, was created by a Spanish priest who later became a bishop!)

Oh so you think I forgot about Pawns? Wrong! Pawns = Some call them soldiers, and some call them stones or rocks!

Now my theory:

It is possible that by translating, a castle, became a rook, after all a castle, is built using rocks. Why didn't the European remove the term "pawn"?

By definition a Pawn is the condition of being held as a pledge against the payment of a loan. All the poor and the farmers were "Pawns".

Remember that Chess was introduced to Europe in mid centuries and only the wealthy played it, so the term pawn has a very significant meaning, the weakest on the board in a Feudal society, that would fight for the king in the hope of being promoted! So they left the name as is for that piece.

Small Edit To My Initial Answer

You might be wondering: Why the hell would Arabs call "Pawns" as "Rocks" in the first place?

That's because, Arabs play a board game called Tables, the game as we play it today, was created in Turkey, (I don't give a damn about what Wikipedia has to say about the history of the game) and the Turks have invaded the Arabic world for a long time, so that's how we got it.

The game is played by stones or rocks, rounded pieces, now they are made from plastic, but not back then. The Tables game is far more popular than Chess or whatever you call it in the Arabic world today.

The way you play the game is by pushing the pieces to the other end of the board, and you win (I'm not going to go over the rules, but that's the idea)

There's also Checkers, which originated in Iraq some believe, and is still more popular than Chess nowadays in the Arabic world.  And the pieces move very similar to Pawns and again were made from rocks. So why creating a "Pawn" shaped piece, when you can use rocks and start playing?

Sources

The history of the chess pieces
Chess Piece history: Rook
Why is a rook called a rook?


Alpha-beta safe on incomplete tree? I'm writing a simple chess program from scratch on a hobbyist basis. I think there is something fundamental I'm overlooking or don't understand.

I read the following http://chessprogramming.wikispaces.com/Alpha-Beta, as well as other articles, e.g. the Wikipedia one. I've also implemented alpha-beta blindly before just by following pseudo-code. I believe I understand how alpha-beta can guarantee no unsafe pruning takes place on a complete search tree, i.e. if you have the whole search tree, and there are no unexplored nodes beyond the horizon.

What I don't understand is how alpha-beta can guarantee no unsafe pruning takes place on an incomplete search tree which does contain such unexplored nodes beyond the horizon, which chess always results in, unless evaluating endgames with a small enough tree.

Consider the following explanation from: http://chessprogramming.wikispaces.com/Alpha-Beta

  Say it is White's turn to move, and we are searching to a depth of 2
  (that is, we are consider all of White's moves, and all of Black's
  responses to each of those moves.) First we pick one of White's
  possible moves - let's call this Possible Move #1. We consider this
  move and every possible response to this move by black. After this
  analysis, we determine that the result of making Possible Move #1 is
  an even position. Then, we move on and consider another of White's
  possible moves (Possible Move #2.) When we consider the first possible
  counter-move by black, we discover that playing this results in black
  winning a Rook! In this situation, we can safely ignore all of Black's
  other possible responses to Possible Move #2 because we already know
  that Possible Move #1 is better.

This seems to be false to me, exploring further nodes on the branch of "Possible Move" #2, e.g. a couple more ply, could result in black being guaranteed checkmate?

Hence pruning away this as a possible move is not safe.

What am I missing?

I know this ties in with the horizon effect and quiescence search, however I don't understand how alpha-beta alone, when used in this way on an incomplete search tree can be considered "safe". But I'm sure there is something I'm overlooking and it would be great with some pointers.

As far as I can tell, you are crystal clear conceptually, and you aren't actually missing anything. I think the source of any apparent conflict between your understanding and the quoted passage is that you may be reading the passage to be claiming more than it really is. Here it is again, with some added emphasis:

  Say it is White's turn to move, and we are searching to a depth of 2 (that is, we are consider all of White's moves, and all of Black's responses to each of those moves.) First we pick one of White's possible moves - let's call this Possible Move #1. We consider this move and every possible response to this move by black. After this analysis, we determine that the result of making Possible Move #1 is an even position. Then, we move on and consider another of White's possible moves (Possible Move #2.) When we consider the first possible counter-move by black, we discover that playing this results in black winning a Rook! In this situation, we can safely ignore all of Black's other possible responses to Possible Move #2 because we already know that Possible Move #1 is better.

I think that the only point being made here is that in this particular situation, "we already know that Possible Move #1 is better" as far as our limited depth search is concerned. That is, we have fixed this depth of 2 ply for our search in advance, that is as far as our knowledge is going to go, and the information discovered in the scenario does conclusively show that within the scope of the next 2 plies Possible Move #1 is better than Possible Move #2.

Your worry that something crucial might be being missed beyond that limit is absolutely correct, of course, and is why ideally such an algorithm would search all the way to the end of the entire chess game tree. That would be the only way to know that we have no "unsafe pruning," or in other words that we are playing optimally. But going that far isn't feasible (except for e.g. certain endgame positions, as you note, or say positions that are close to a forced conclusion of a game), so in whatever reasonable, finite amount of time an engine will have to search, it will only make it to some particular depth N that is insufficient for complete certainty. The point being made in the above passage isn't that we know Possible Move #1 is truly better than Possible Move #2 (i.e. with respect to the entire game tree), but only that we know it is definitely better with respect to the fixed depth N we actually get to search. But that's OK, as that's all we could possibly be sure of, which is exactly your point.


Is it improper etiquette to ask your opponent what his/her rating is before the game? Suppose you're playing in a tournament. For the purpose of filling up your scoresheet, is it improper etiquette to ask your opponent what his/her rating is before the game?

Yesterday, I played a tournament match, and at the table next to me the guy asked his opponent for his rating. “I don’t really know...” was the reply, “about 1580, I think. And yours?”

“Euhm... about 1400”, the guy mumbles in reply.

If you don’t want to give out your exact rating in reply or you don’t know it yourself, I would not ask the question to begin with. Furthermore, I thought the question was bad etiquette and would not really be happy with my opponent asking it.

Finally, where I live, most tournaments have lists of all participating players and their rating which you can look at. So start the game, and then after a couple of moves, when your opponent is thinking, you can always go check the list.

PS: I find that I play better when I don’t know my opponent's rating. Once I know his rating is a lot better, I get nervous and consider myself lost from the start. When I know his rating is much lower, I tend to play reckless and make mistakes.


Are all KQvK positions winnable if it's not stalemate and Black can't capture on current move? Are all KQvK positions winnable if the position isn't in itself a stalemate and Black cannot capture on the current move?

Yes, all KQvK positions are won under these conditions (no stalemate, no capture). The same holds for KRvK.

The only possibilities for such basic endgames not to be won under your conditions would be:

a piece has too few square available and can be captured by the black king (not immediately but in the next move)
white on the move cannot avoid stalemate (or material loss)

An example for the first case (black to move):

[FEN "7N/8/8/4k3/8/8/6K1/7B b - - 0 1"]

the second case (white to move) looks like this (to avoid stalemate, white's king has to go to the d file when after Kb7, black wins the bishop or knight):

[FEN "kB6/2K5/N7/8/8/8/8/8 w - - 0 1"]

However with the KQvK and KRvK, the queen/rook always have enough space to avoid these problems.


How to play against the Allgaier, Horny Defense? The Allgaier, Horny Defense in the King's Gambit is given by the sequence:

[FEN ""]

1. e4 e5 2. f4 exf4 3. Nf3 g5 4. h4 g4 5. Ng5 h6 6. Nxf7 Kxf7 7. Qxg4 Nf6 8. Qxf4 Bd6

I'm a King's Gambit player, and I'm rated 1650 USCF, although I'm tactically much, much stronger (my biggest weakness is not knowing theory). This is a defense that my computer often plays against me (and assesses the position after the opening moves as +2 advantage for black, which doesn't seem reasonable to me), and I don't know how to deal with it. Any strategic/positional ideas that I should be aware of? I would also like to know how you guys would deal with the annoying

[FEN ""]

1.e4 e5 2.f4 Qh4+ 3.g3 Qe7

as white. What kind of strategy should white adapt there?

Please don't berate my opening choice, and refrain from telling me to read up on theory. While that is a good idea, I am more interested in strategic ideas of this variation of the King's Gambit.

If you type your moves into Google it will actually find games that open that way.  It's quite cool. I use the move numbers as well as the actual moves.  Basically, a copy-paste of the first few moves.  Your game seems to be a ECO "C30".

For your Qh4+ question, I get this link.

The gist is you get this continuation:

[fen ""]
1. e4 e5 2. f4 Qh4+ 3. g3 Qe7 4. fxe5 d6 5. exd6 Qxe4+ 6. Qe2
Qxe2+ 7. Nxe2 Bxd6

And you really don't have a lot to worry about.  In the games in the link above, White developed easily, Black's pawn structure was smashed, and White won pretty easy endgames.


Could the black king move to C5? Could the black king move to C5?

No, it is checkmate. Even if Pb4 is pinned, it still controls square c5, preventing the black king to move there.

Check rules 3.9.1 and 3.9.2 of the laws of chess.

  3.9.1
  The king is said to be 'in check' if it is attacked by one or more of the opponent's pieces, even if such pieces are constrained from moving to the square occupied by the king because they would then leave or place their own king in check.

  3.9.2
  No piece can be moved that will either expose the king of the same colour to check or leave that king in check.

(emphasis mine)

1...Kc5 is illegal.


Multiple teams from the same country in Swiss system Doesn't it create bias for the country?

Disclaimer: I realize that benefits of having more teams from the same country far outweigh possible drawbacks, just trying to reason how possibly "unfair" can this be for the other teams, and / if this can be improved.

Imagine last decisive round where two teams from the same country are paired between each other. Will it be a fair match? Does it make sense to avoid such pairings?

There is a tradeoff between making the pairings that "should" be made according to the strict pairing rules, and attempting to prevent collusion.  Imagine this scenario:

Russia 1: 8.5
Russia 2: 8
India:    8
Peru:     7.5

Which is more unfair: to have Russia 1 play Russia 2 and have a possible prearranged result, or to prevent Russia 1 and Russia 2 from competing, causing Russia 2 to play a team with a lower score instead of the strong Russia 1 team?

There are several ways to handle this.  You could switch the pairings only when it does not cause a team to be moved up or down a pairing group. You could switch the pairings in any round except the last two. Or you could not switch them, and watch closely for signs that the players aren't playing seriously.


In the Slav, after 1. d4 d5 2. c4 c6 3. Nf3 Nf6, what are all the differences between 4. Qc2 and 4. Qb3? In the Slav, after 1. d4 d5 2. c4 c6 3. Nf3 Nf6 :

What are all the differences between 4. Qc2 and 4. Qb3 ?

Which one of them is better to reach some Catalan type positions?

Which one of them tends to lead (on average) to the most solid, quiet, positional, slow, safe and strategic positions (i.e. the least sharp and tactical positions) ?

Is one of the two objectively stronger than the other?

.

I have made some research and here is what I've found:

If Black plays 4...dxc4 then they transpose (except if White is crazy enough to try the rare gambit 4. Qc2 dxc4 5. e4 but I'm never going to play this anyway).

Against 4. Qc2 Black often plays 4...g6, while against 4. Qb3 the move 4...g6 seems to be less popular.

If Black plays 4...e6, maybe it makes a difference if the Queen is on c2 or on b3. Not sure.

After quickly looking at the differences, I think Qb3 is more suited if you want to fianchetto.

The queen puts pressure on b7 and d5 and combines nicely with a fianchettoed king bishop.

If the queen is on c2 black often plays g6, planning to fianchetto and also play Bf5 with tempo.

Both moves are equaly popular. The choice is yours!


What features can I add to this FIDE chess application? (edits made 2/25) EDIT: Most of the app is completed. Now all I have to complete is implementation of FIDE arbiters, a dynamic 3d plot (right now it only has 3 variables being plotted, no inputs affect it), adding more FIDE data (based on months) and perhaps including USCF chess data (I have the latest data set for all of the states).

I have made 3 adjustments to this post.

1.Include a dynamic time series chart that lets you see more than one player at a time: This was very time consuming to produce!.

2.Include an overlayed histogram/density curve.

3.Include 3d scatterplot

4.Improve the layout of the app

FIDE CHESS APPLICATION

Other than an interactive chess board itself (which would be a different animal in itself), what can I add to this application to improve upon visualizing and summarizing aggregated FIDE chess statistics? I am planning also to add a time series plot and a motion chart for aggregated historical data.

After I have completed it, I will put up the source code onto github/mediafire for those who are interested in the programming aspect of this. I will also eventually find a place to host this application so that you may use at your leisure.

Here is a picture of the application itself. The left side has filters that effect the output on the right side.

Here are a few images of features I have put in it.

Key for graphs below:

The first graph is an interactive map that outputs the number of FIDE rated players for each country and plots it onto a map.
The second graph is a normalized histogram, or density curve describing the FIDE ratings distribution.
Similiar to the map, this is a barplot of the number players in each country
The globe is the map, but a more appealing version of the map.
Ideally, I will be able to include a 2D/3D time series plot, unsure if it will be possible given how the datasets are structured. I would plot aggregated chess statistics of the FIDE chess population or of individual players here.
A google motion chart, similar to a time series plot, but more interactive and visually appealing. As with the time series plot, I would plot aggregated chess statistics of the FIDE chess population or of individual players here.
Scatterplot of 3 variables

Is there anything else I can add to further visual FIDE chess data? Also,  making suggestions to further improve upon what I have would be good too.

First of all, good luck! It looks like a really interesting project.

As to suggestions:

1) What are you thinking of calling the app? From what you have shown here, maybe "FIDE Player Statistics"?

2) What is the situation regarding ownership and copyright of the data? Maybe you should ask FIDE? There again, as far as I know they don't make the underlying data publicly available so you have to "mine" the data via appropriately constructed web requests. In this case I don't think you would need permission.

3) You could add displays for player titles like GM, IM, FM, CM, WGM, WIM, etc.

4) You could include arbiter information - IA, FA

5) Also trainers and international organizers.

6) For all of your statistics to break out the data in federation terms. This is almost country level but some countries have a privileged situation. For instance the UK actually has separate English, Scottish, Welsh federations, etc. So, allow comparison of titled players per federation, titled players per thousand players per federation. Could be fascinating to see how Russia performs here. Is it still number 1 chess country / federation?

7) Same for arbiters.

8) Same for organizers.

9) Same for trainers.

I will be very interested in the results of this project. It looks fascinating. Please keep us informed!


Can Black play for a win here? In the position below:

I was Black and I was not sure how to proceed. Finally, I decided to play aggressively with g5. I know it was too risky and weakening, but I did not see what else to do. After checking the computer suggestions, it looks like Black should only shuffle its pieces around Re8 Qf8...

Is that all Black can do? What are your thoughts on this position?

Thanks in advance.

Can black play for a win? Heck yes! This is totally won for black.

I did not even realize you were up a pawn at first, and I was thinking there is a clear plan here.

First, here is the analysis of the position.

You are up a pawn.
You have the better minor piece.
White is weakened on the queen-side since black can put a piece on c4, and b3 is just horrible then leaving c3 super weak, so that cannot be played.
f4 has also weakened white's king-side.
Black has a clear, and simple plan.

Here is the plan for black:

Black's play is on the queen-side. He will gradually push the pawns, carrying out a "minority attack". That is when a smaller number of pawns push and trade down against a larger number, leaving the larger number with one remaining, but weak, pawn.
Play Rc4 right now so there is no time for Nd4 hanging f4 to Bxf4.
Bring the other rook to c8, and then the Q goes to f8 and over to the queen side too.
The Bd6 might even redeploy to g7 to provide additional defense against any white all-out attack on your king, while still hitting the queen-side.
Then play a6 (or maybe a5 in one go), b5, a5 and then b4. After trades, white will be left with either a b-pawn or c-pawn, which can be attacked by the black major pieces, and possibly the black bishop. It is possible that the black major pieces will have to be redeployed to help execute b4, for example a Rb8, or the queen helping. It is also possible that one might go to a8 to take control of that file after some trades.
Win the extra pawn, and then push your central pawns and win.

This plan is very common, and even if black were not up a pawn here, this would still be much more pleasant for him.


What is the best line in the Fried Liver The following is suggested by my computer (Stockfish) as an improvement to a line in the Fried Liver played in Shirov v Sulskis 2014 and suggested as a definite refutation in some places - Shirov's key move was 9. a3.

As an improvement, instead of the Sulskis move 11... Kd6, play 11... Qh4 as follows, with suggested follow-up (I have tested at some depth, but the positions are not straightforward and there are alternative moves).

[FEN ""]
1. e4 e5
2. Nf3 Nc6
3. Bc4 Nf6
4. Ng5 d5
5. exd5 Nxd5
6. Nxf7 Kxf7
7. Qf3+ Ke6
8. Nc3  Ncb4
9. a3   Nc2+
10. Kd1  Nxa1
11. Nxd5 Qh4
12. d3  Kd6
13. h3  Be6
14. Ne3  e4
15. Nf5+ Kc6
16. Nxh4 exf3
17. Bxe6 fxg2
18. Nxg2

With advantage to black. 11... Qh4 is an extraordinary move so I'd appreciate any commentary on that. Is it really advantage black? Can anyone find an improvement in this line (from move 11) for white?

My computer (at significant depth) would play 9 Bb3 as an improvement for white, instead of Shirov's move (I'm taking the position after move 8 as basic) - but this secures only a modest advantage for white and it looks as though the position can be defended. Is there any deep published analysis of these lines?

Recently, GM L'Ami made a DVD covering the Two Knights and the Fried Liver attack. According to the article, he suggests ideas for both white and black, so maybe he discusses 9.Bb3 (instead of 9.a3) and 11....Qh4 (instead of 11....Kd6).

Furthermore I'd like to add that, although it has been played by a couple of grandmasters, 5....Nxd5 is considered to be very risky for black.

The main line of the variation is 5....Na5. According to the Game Database of ChessTempo, it is by far the most popular response to 4.Ng5. After 6.Bb5+ c6 7.dxc6 bxc6, black is a pawn down, but is ahead in development. This position is one of the tabiyas of 1.e4 e5: has black sufficient compensation for the pawn or not?


Seconds of Magnus Carlsen Has it been revealed who helped Magnus Carlsen in preparing and during the World Chess Championship against Karjakin?

So far, following seconds have been revealed (NRK, ChessBase):

GM Peter Heine Nielsen (no surprise as he was part of team Carlsen in WCC 2014)
GM Laurent Fressinet (also no surprise as he was part of team Carlsen in WCC 2013 and WCC 2014)
GM Maxime Vachier-Lagrave (quite a surprise as he is the current world's nr. 4)
GM Nils Grandelius
GM Jan Gustafsson (the tweet of RadioJan was not a joke)
GM Samuel Shankland (a surprise to many, however it was revealed that he also helped for WCC 2014)

Another surprise is that GM Jon Ludvig Hammer was not part of Carlsen's team for this match, while he was for WCC 2013 and WCC 2014. Instead, he chose to do commentary work for VG and Chess.com.


What are some of the chess databases in the public domain that can be used for commercial purpose? What chess databases allow commercial use without having to reveal source code as part of their license? I see a few chess databases online, even the huge databases on lichess. I wonder which of these can be used as part of a commercial project without having to worry about licenses and unfair usage.

I don´t think chess games are copyrightable, as they´re just a collection of facts, so games of chess are not considered by the courts to be anyone´s property.  I would say that you are free to comercially reproduce a game, as long it´s just that, the moves played in that game.
To put in perspective, if you took a screenshot of the result of a videogame, for example Civilization, or if you recorded a song in Guitar Hero, then that would be the intellectual property of the creating videogame company.  Following that pattern, any PGN would be the legal property of whoever invented chess, but I believe the copyright may have expired by now.


What is the main idea of the Morozevich variation in the French vs. the Tarrasch? What is the main idea of the Morozevich variation in the French vs. the Tarrasch variation?

  1.e4 e6 2.d4 d5 3.Nd2 Be7

In other words, how can Black benefit from the slightly unusual development of the Bishop before the Knight?

3...Be7 is mainly an attempt to side-step some of the other well-known theoretical variations, while making white to first commit another developing move before deciding how to continue. For instance, the usual 3...Nf6 often leads to 4.e5 Nfd7 and black has already committed the knight to d7 while white has all three attractive options of Bd3, f4 (further discussed in the 2nd diagram) and Ngf3. Instead with 3...Be7 first, many more alternatives survive, such as:

All diagrams contain annotations.

 [title "3...Be7 possible follow-ups in Tarrasch variation"]
 [fen "rnbqk1nr/ppp1bppp/4p3/3p4/3PP3/8/PPPN1PPP/R1BQKBNR w KQkq - 2 4"]

 4.Ngf3 Nf6 5.e5 Nfd7 {You see by simply having delayed Nf6 by one move and kept an option such as Nh6 open, white's choice of 4.e5 5.f4 is already less attractive} (4.e5 Nh6 {taking advantage of the early Nd2 blinding the h6 square for white so the knight can now re-route via h6-f5. This maneuver is also often employed in f4 variations of the French.} 5.Bd3 c5) (4.Bd3 c5 5.c3 cxd4 6.cxd4 dxe4 7.Nxe4 Nf6) (4.Ngf3 Nf6 5.e5 Ne4)

So in the above side-lines not only has black kept some additional options open with 3...Be7 but it has also made a couple of key variations less attractive for white, such the usual f4 lines in the Tarrasch (which is also briefly touched upon on the wikipedia page of French Defense), for example:

 [title "classical 3...Nf6 and the f4 variation - compared to 3...Be7 :"]
 [fen "rnbqkbnr/ppp2ppp/4p3/3p4/3PP3/8/PPPN1PPP/R1BQKBNR b KQkq - 1 3"]

 3...Nf6 (3...Be7 4.e5 c5 5.c3 Nc6 {You see the difference now more clearly: 4.e5 is no longer with tempo, thus allowing black to start undermining the central pawn chain with c5 one move earlier, followed by Nc6, practically never allowing white an easy route towards the previously mentioned main variation.}) 4.e5 Nfd7 5.f4 {notice the knight's already on d7} c5 6.c3 {nothing really challenged white's f4 play}


Why didn't Spassky play 26. g3 in game 5 of Fischer-Spassky (1972)? Fischer's play was powerful in this Nimzo-Indian, achieving a strong knight against two bishops in a closed position. The knight became a monster on f4. But why did Spassky let the knight reach f4? The idea of playing 26. g3 to prevent the knight from getting there seems like an obvious idea. If not for f4, it's hard to find a good square for the knight. Sure, the move 26. g3 has some drawbacks, like weakening the light squares around white's king and making the dark-squared bishop even worse. But it looks like the benefit would outweigh the drawbacks. What are your thoughts?

I used the chessgames.com engine to analyze the position and was surprised to find that 26. g3 wasn't even in the top two moves. I wonder why this is? Why did neither Spassky nor the chessgames.com engine choose 26. g3 as a move?

[fen ""]
[Event "Spassky - Fischer World Championship Match"]
[Site "Reykjavik ISL"]
[Date "1972.07.20"]
[EventDate "?"]
[Round "5"]
[Result "0-1"]
[White "Boris Spassky"]
[Black "Robert James Fischer"]
[ECO "E41"]

1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. Nf3 c5 5. e3 Nc6 6. Bd3 Bxc3+ 7. bxc3 d6 8. e4 e5 9. d5 Ne7 10. Nh4 h6 11. f4 Ng6 12. Nxg6 fxg6 13. fxe5 dxe5 14. Be3 b6 15. O-O O-O 16. a4 a5 17. Rb1 Bd7 18. Rb2 Rb8 19. Rbf2 Qe7 20. Bc2 g5 21. Bd2 Qe8 22. Be1 Qg6 23. Qd3 Nh5 24. Rxf8+ Rxf8 25. Rxf8+ Kxf8 26. Bd1 Nf4 27. Qc2 Bxa4 0-1

I'd actually argue that the drawbacks of g3 are worse than Black getting a knight on f4. White permanently weakens the kingside light squares and blocks in his dark-squared bishop. Meanwhile, Black getting a knight on f4 is a bit unpleasant, but it's not necessarily a permanent problem.

Spassky probably thought that after 26...Nf4 27.Qc2, he was holding. He missed 27...Bxa4 of course, but if he had played 27.Qb1 instead, Komodo actually gives an equal evaluation. It's funner to play Black, but finding a plan to breakthrough is nontrivial.

After 26.g3 Nf6, Black is planning to play ...Qh5 and aggressively capitalize on White's weak light squares. If White stops this with 27.Qd1, Black has 27...Bg4.


Looking for a repertoire book on the Spanish with 5.d3 (4.d3 vs the Berlin)? Does anyone know of a good (or not so) repertoire book on the Spanish with 5.d3 vs the main line and 4.d3 vs the Berlin? Is there such a thing on the market? I've already got Andrew Martin's DVD The ABC of the Ruy Lopez, but still I'd like to have something to read on the subject, something that would be a bit more thorough, etc.

The Ruy Lopez: Move by Move by Neil McDonald contains both a d3- and a main line repertoire against the Ruy Lopez.


Why is stalemate a draw? It is so difficult to force stalemate and sometimes unintentional too, so why is stalemate a draw?

  As the opponent doesn't have a further move, why is it not considered a win?

Stalemate is a draw in classical chess yet there are other chess variants both historical and modern where stalemate is not a draw.

Very early versions of Chess, such as Shatranj Chess (props to Andrew Latham) declare the player causing stalemate the winner and even today there are callings to return to that rule.

for example:

Larry Kaufman Chess Life Sept. 2009 writes:

  "calling stalemate a draw is totally illogical, since it represents
  the ultimate zugzwang, where any move would get your king taken"

A typical counter to this point is that Chess tradition dictates that a stalemate cannot result in a win for the stalemating player because it would require a suicidal move from the stalemated player (moving your king into check is, in most forms of chess, an illegal move). If there are no moves on the board that you are able to make (other then resigning) then in making the stalemating move your opponent has effectively ended the game without a definitive result (capture of the king) and is judged to have not won the game.

So.. "In Classical Chess what is the probable origin of stalemate being considered a draw?"

The earliest reference I can find to Stalemate being a draw in formalised chess rules is 13th century Italy where the version of Chess played declared that a game could only be won by checkmate or resignation. Stalemate, under those terms, describes a state where a player cannot make a legal move. In effect the game has stalled in a state where neither player can achieve Checkmate and is drawn.

Stalemate as a draw then spread to Germany (1400s), Spain (1600s) and throughout Europe by 19th Century when the formal rules of what we know as classical chess were put in place.

England was one of the final adopters of Stalemate as a draw in the 1800s (up until that point the stalemated player had actually been declared the winner).

Opinion:

Yes tradition does favors the player in stalemate but it has been that way for a very long time. The flipping of that advantage to the stalemating player would greatly change the nature of the endgame (and thus the game of chess and a huge amount of chess theory), which is probably why such arguments have not recieved too much traction.


How to make Stockfish always give the score from white's perspective in Winboard? I use Stockfish 4 to analyze chess games in both Babaschess and Winboard.  From time to time, Stockfish outputs a line with info like time, score, principal variation, etc.  In Babaschess, the 'score' behaves as I would expect; it is always from white's perspective.  If white is doing well, the score is always positive; if black is doing well, the score is always negative.  However, in Winboard, the score is always from the perspective of the current player, meaning that it tends to veer from positive-negative-positive-negative, if one player stays in the lead.

How can I get the score to behave in Winboard as it does in Babaschess, and always be from white's perspective; always negative if black is doing well?  Here's the line in my Winboard 'tags' that I use to load the Stockfish engine:

"Stockfish" -fcp "stockfish_4_32bit.exe" -fd "C:\Program Files\BabasChess\Engines\stockfish-4-win\Windows" -fUCI

Use /firstScoreAbs true command option (Tested in version 4.7.2):

  If this option is set, the score reported by the engine is taken to be
  that in favor of white, even when the engine plays black.

"stockfish_4_32bit.exe" -fd "path\Stockfish" -fUCI  /firstScoreAbs true
                                                    ^^^^^^^^^^^^^^^^^^^


Why shouldn't I play c5 in Queen's Gambit Declined as white? My favorite opening is the Queen's Gambit Declined, and I will often reach positions like this
[FEN ""]
1. d4 d5 2. c4 e6 3. Nf3 Nf6 4. e3 c6 5. Nc3 Be7 6. Bd2 O-O 7. c5

Where I decide to play c5 after my rook is safe. If black goes after the c5 pawn with their pawns then I defend it with mine, and when I run this with Stockfish the pawn is indeed not captured.
The thing is, this move is generally always classified as an "inaccuracy" or "good move", but never as "excellent" or "best". To me, it feels like this move severely cramps black's dark-squared bishop as well as just gaining me a lot of space and control on the Queen's side.

In general, why is playing c5 as white in the Queen's Gambit Declined not a good idea? As black, how should I go about defending against this move?

In most cases White doesn't want to play c5 in such positions because it takes the pressure of the black center. Yes, it cramps the black queen side a bit but it allows Black to play e5 at some point and break the center instead, freeing their c8 bishop and more. With the white pawn on c4 that is more difficult, sometimes d5 may just be hanging after e5 and even if not White can take on e5 and d5 to give Black an isolated queens pawn with not much compensation. After c5 Black has no such problems and can freely play e5, banking on a well defended d5. If anything it is White then who has to be careful, the d4 might become slightly weak, or after a capture on e5 the c5 might get into trouble later.
Of course as with everything it depends on the position. E.g. if Black already committed to a6 like in a Chebanenko Slav then c5 may be a good move as then b6 really is quite weak.
(also I should give a disclaimer that I'm not a d4 player so take this with a grain of salt)


Why is 5.c3 the most common move in the Ruy Lopez, Berlin defence, Beverwijk variation? Disclaimer: I'm a very, very green player.

After the first 4 moves, all of which seem natural given my understanding of basic opening principles (control the center, develop your knights, etc.), I notice 5. c3 is the most common move, according to this database:

[fen ""]

1. e4 e5
2. Nf3 Nc6
3. Bb5 Bc5
4. O-O Nf6
5. c3

I'm not sure why, though. In particular, it seems really passive. Is it for an eventual d4? If not, what do you see as the reason for this being so common? I would think, e.g., 5. Nc3 would be more common.

I'm not really familiar with this variation, but c3 is a typical move in the Ruy Lopez for a couple of reasons: one, which you already mentioned, is to support d4 (and in this variation, d4 has the added benefit of forcing the black bishop to retreat). The other is to open c2 as a retreat for the bishop, which has a tendency to get pushed back by pawns and then threatened with being traded for a knight. In the Ruy Lopez, the b1 knight is often developed via d2.


What is Syzygy tablebases? I just want to know in simple language exactly, What the Syzygy tablebases are, Why they are used, What are their advantages, disadvantages?

Tablebases are databases of endgame positions, with few pieces left on the board (say a 5-man tablebase, which consists of all legal positions with 5 pieces on the board in total, including kings, say K+Q vs. K+R+B). These databases have the positions 'connected', i.e. they also contain the moves to get from one legal position to another (in particular, moves that eventually lead to mate). This allows a chess program, in such positions, to look straight into the tablebase, rather than to calculate via the engine.

Tablebases are perfect, in the sense that it can tell you number of moves to mate, and playing a position against a program using tablebases (in positions with very few pieces left) is akin to "playing with god". So as an advantage, they save computational time and allow your machine to play certain endgame positions perfectly. The disadvantage is that they take up a large amount of memory space.

Owing to the memory issue, compression techniques help to reduce the space taken up by the tablebases. Syzygy tablebases are relatively new (introduced about 2 years ago), compared to the Nalimov tablebases which have been around for quite a while (itself being a compression improvement over previous tablebases). The Nalimov 6-man tablebases take up over 1TB of memory space, whereas the Syzygy bases use less than 200GB.

The different names in front of 'tablebases', e.g. Syzygy and Nalimov, refer to nothing more than compression methods. For all practical purposes, there is absolutely no difference between the content of Syzygy and Nalimov tablebases; a computer that uses either one will play at the same strength (perfect!). Their only difference is the memory space they occupy.

(The possible difference in content, if any, is subtle: first off, every legal position in the tablebase has an evaluation attached to it (draw/win/loss in X moves). However, some positions may contain a sequence of moves to mate that require breaking the 50-move rule; the evaluations of these positions in the tablebases may be changed to accommodate for this, e.g. W/L/D/"win but break 50-move rule", but in any practical game, you are pretty much guaranteed that you will never see this difference.)


An objective measure of the difference in strength between top programs and top human players in the four most popular forms of chess? Is there an objective measure of the superiority (or otherwise) that the strongest computer programs enjoy over the strongest human players which can be compared across the four main forms of chess, namely western chess, xiang qi (Chinese chess), shogi (Japanese chess), and makruk (Thai chess)? For example, can it be said that on comparable Elo scales the programs have say an x point advantage in western chess, a y point one in Chinese chess, and lag behind in the other two games by z points?

I would have to answer no in my opinion. The four forms of chess are different. Shogi from what I remember is a form of chess where capturing an opponent's piece allows you to, at a time of your choosing, put one of that piece on the board as yours. Now that is a level of tactical complexity that surely gives any engine a huge advantage over any strength of human. I have played a little Xiang Qi and I would say the same; in the 90's when Chinese players played Professional western chess for the first time they were awesome tacticians; Xiang Qi as their previous game being very tactical led to that.


Can Black crash through? I wonder if White can defend below position:

[Title "White to move"]
[fen "r4rk1/pppq2pp/2np1n2/2b1p1B1/8/2NP1N1b/PPP1BPP1/R2QR1K1 w - - 0 1"]

[FEN "r4rk1/pppq2pp/2np1n2/2b1p1B1/8/2NP1N1b/PPP1BPP1/R2QR1K1 w - - 0 1"]

    1.Qd2 h6 2.Be3 Bxe3 3.fxe3 (3.Qxe3 Be6 4.Nd2 Rf7 5.Nde4 Ng4 6.Qg3 Raf8 7.Bf3 Nd4 8.Bxg4 Bxg4 9.Rac1 Be6 10.Ne2 Qa4 11.Nxd4 Qxd4 {-1.82. It took Stockfish 20 minutes to find `3...Be6`. It's preferred move until then was `3...Bg4`. Black is having a fine game.}) Be6 {So what we see here is that Black's attack is over. But the damage is done. He regroups with his extra pawn and better pawn structure.} 4.a3 Ne7 5.Ne4 {This is the best White has? To induce a doubled center pawn?} (5.e4 c5 6.Rf1 Rf7 7.Qe1 Raf8 8.Nd2 Ng6 9.Kh1 Nf4 10.Bf3 Nh7 11.Nd1 Ng5 12.Ne3 Qa4 13.b3 Qd4 14.Rd1 b5 15.Bg4 Bxg4 16.Nxg4 c4 17.dxc4 bxc4 18.bxc4 Qb2 {-1.78. White's position is passive and he gets picked apart.}) Nxe4 6.dxe4 Qc6 7.Bd3 Rf6 8.Rf1 Raf8 9.Qb4 R6f7 10.Nd2 b6 11.Rxf7 Rxf7 12.Bc4 Bxc4 13.Qxc4 Qxc4 14.Nxc4 Rf6 15.Nd2 Kf7 16.Rf1 Rxf1+ 17.Kxf1 Ng8 18.Kf2 Nf6 19.Ke2 Ke7 20.Kd3 Ke6 21.c3 a6 22.Kc4 b5+ 23.Kd3 { -1.58 }

    [FEN "r4rk1/pppq2pp/2np1n2/2b1p1B1/8/2NP1N1b/PPP1BPP1/R2QR1K1 w - - 0 1"]

    1.gxh3 Qxh3 2.Bf1 Bxf2+ 3.Kxf2 Ng4+ 4.Kg1 Qg3+ 5.Bg2 Nd4 6.Rf1 Nxf3+ 7.Rxf3 Rxf3 8.Qxf3 Qh2+ 9.Kf1 Rf8 10.Qxf8+ Kxf8 {White's King is flapping in the breeze; what White may be up in material he'll lose by being purely defensive with said pieces. White will be able to pick off pawns at will.} 11.Bd2 Qh4 12.Nd1 c6 13.Be1 Nh2+ 14.Ke2 Qh5+ 15.Kf2 Ng4+ 16.Kf1 d5 17.Bd2 Qh4 18.Be1 Nh2+ 19.Ke2 Qh5+ 20.Kf2 Ng4+ 21.Kf1 Kf7 22.a4 Qg5 23.Ke2 Nh2 24.Kf2 Qh4+ 25.Ke2 Qh5+ 26.Kf2 Qg5 27.Ne3 h5 28.a5 h4 29.a6 b6 30.Nf1 h3 31.Bxh3 Qf4+ 32.Kg1 Nf3+ 33.Kg2 Nd4 34.Bg3 Qf3+ 35.Kh2 Nxc2 36.Rc1 {-2.39 }

It's Kentucky Derby Day, and I live in Louisville, so celebrating is mandatory. More To Come.

As always, if you have any variations you want to see, let me know.


Why is it not a checkmate? I am new to chess. I have tried to learn checkmate from the video lesson in chess24 website. There, in one question, it marked my answer wrong and said that it was not checkmate. Can anyone please explain the reason ?

I do apologize if I asked anything stupid. Thanks in advance.

Welcome to Chess Stack Exchange.
I believe you're doing well here.  It is surely a checkmate. Probably the website isn't programmed that way to recognize that move. But, as per your question, this is clearly a checkmate that resembles the one-rook-mate pattern.


How many attacks can be focused on one point? How many "possible" attacks can be focused on one point on the board? For instance the pawn in E5:

What is the maximum (realistic) amount of attacks that are focused on a single point on the board?

Not sure what you mean by "realistic".

Basically you can attack it with 8 knights plus 7 other pieces attacking horizontally/vertically/diagonally, i.e. from each cardinal direction (North, NorthEast, East,...) except for one.

For example:

8/3N1N2/2NBQBN1/3RpR2/2NPK1N1/3N1N2/8/8 w - - 1 1

Notes:

At the start of the game each player has 16 pieces of which two are  bishops of opposite color. That's why one of the bishops will not be able to attack the square and the maximum number is 15.
In the example 7 of the knights are fixed. You can think of (1) using other pieces to attack along the cardinal directions or (2) replace one knight with a piece attacking from f4.
You can move pieces that attack along the cardinal directions further away from the attacked square but this does not help to focus more pieces on the square unless you count batteries double. In any case you are running out of pieces to achieve more than 15 attacks.
It is possible to get 8 knights and two dark squared bishops through pawn promotion. In the example 6 pawns have been promoted to knights and one pawn to a bishop which together with the remaining pawn sums to 8 pawns.


On the feasibility of a KBN-K mate within 50 moves using a particular method Prove that it is possible, from any starting KBN-K position, to accomplish the mate by manoeuvering to arrive at key positions from a well-known method or strategy whilst the losing king actively tries to avoid reaching the key positions that would lead to mate within 50 moves. In terms of the players' goals, the winning player's goal is to reach the key positions and still have moves to mate within 50 moves, and the losing player's goal is to avoid getting mated within 50 moves.
Given a starting KBN-K position, there exist paths through the tree of variations satisfying the winning player's goal with optimal play by the losing player. Is this satisfied for ALL legal KBNK positions using that particular stratagem only? How would one go about attempting to prove this using KBN-K tablebases?

Is this satisfied for ALL legal KBNK positions using that particular stratagem only?

Absolutely not! Please don't try to prove something that's impossible. Consider this position.
[startflipped ""]
[FEN "3kB3/4N3/8/8/8/8/8/3K4 b - - 0 1"]


Are there any sources of massive transposition tables? Do transposition databases exist the way tablebases do? Would an engine be able to take advantage of a pre-calculated TD? Is there a benefit to players when studying if they had access to pre-calculated positions?

What I am imagining is a sort of Wikipedia for chess positions. Rather than focusing on perfect endgames or history of play, the emphasis would be on the position itself rather than the moves leading up to it. Users would then “kibitz” the individual positions, with popular ones rising to the top based on visits or appearance in games.

Does something like this already exist? I’m aware this is similar to some of the features of “Let’s Check” from Chessbase. I’m thinking open, like tablebases are.

And on that note, are there any proprietary table bases?

What you're talking about is basically opening books. If an engine has access to hard-set evaluations of common positions fairly early on in the game, then it can play better.

But having a pre-made transposition table/database of positions occurring far after the opening isn't useful, since the chance of reaching any particular position late in the game is extremely low. Unless this position is part of theory, in which case it would be in an opening book.


Suggestions for blindfold exercises I can now name the color of any square. Does anyone have suggestions for  some other visualization exercises I can do to improve my blindfold chess?

A friend of mine (and a stronger player) suggested one exercise which has helped me in developing my visualization skills.

Take a game, any game and read the first two moves of both sides (ie total four plies), visualize the position now on board, then make these moves on board, see if your visualized position was right.

Read the next two moves and visualize the current position then make the moves on board and check if you got it right.

Go through the entire game in these steps of two moves.

once you are fairly comfortable,  try in steps of three moves, Gradually increase the number of moves.

I am doing this for about 8 months now and now I can visualize boards over ~10-12 moves.

Already I play blindfold chess in lichess.org, by making the site speak out opponents move and I entering move through the keyboard. (Even though I look at the board once in ~10 moves)


What are the main tournaments in the chess world? What are the big events that big players visit? Do every big Tournament has an effect on the players rating?

If you wish to know about tournaments for top players, I would direct you to 2700 chess (scroll down under the list of players).

If you consider a " big tournament" an open tournament with let's say 100 participants (and maybe 1 or 2 of them are top players), then do a search in some comprehensive chess calendar, e.g.: chess-calendar.eu or FIDE's calendar.

Not just the biggest tournaments affect player's FIDE rating, almost every small tournament can do that, too (all FIDE needs is some... money).

Therefore the only exceptions I can think of are friendly matches and alternative chess tournaments (Fischer's chess, Basque chess etc.).


Why isn't the active color allowed to be in check in a FEN legal position? The title says it. Reading up on how to describe the position of a board, all of the requirements make sense (like two kings not being on adjacent squares and so on) except for the active color being in check. Why isn't that allowed? What is the rationale behind this?

The active color (i.e. the color which has the next move) is allowed to be in check, and as ajax points out, at most twice.

But perhaps you meant the inactive color not being allowed to be in check.  Why is that?  The answer is: if the inactive color is in check, it would mean that at least the last move by the inactive color was illegal, allowing its own King to remain in or be exposed to check.


LEAP PQ9912 Chess Timer - count up option The advertisements for this clock say that it has a pre-set count up feature, but I cannot find it, nor does the instruction manual say anything about it. Does anyone know if this clock has a count up feature and if so, how to use it?

Thank you.

I honestly don't know either, but as far as I can tell (and if someone else can verify this for me that would be great), this is essentially the same clock as the Wholesale Chess Advanced Digital Timer, except in blue.  If you google that clock and look at pictures, they seem identical, including having the same description of the various modes on the bottom of the clock, laid out in an identical format.  The on/off switch is located in the same place, both clocks have the same shape and the same buttons, and the same modes as far as I can tell (I did not do a mode-by-mode comparison, but they both have 38 pre-defined modes, one user-defined mode numbered 00, and they both allow you to save changes to a single pre-defined mode, labeled F).  Anyway, the Wholesale clock does not seem to have a count-up timer, so I strongly suspect this one does not either.


Can one improve his chess without playing online? I have been playing chess for almost an year and I'm addicted to playing chess on Lichess.
My stats there are:
2100 classical
2000 rapid
1800 blitz

I feel that playing chess online ruins my life and that my life would be much better without it at the moment.

I'm studying at the University and my grades dropped.
I'm not devoted enough in my work place.
I'm barely going out with my friends
I do less sports
I dropped some of my other fun hobbies
I sleep very late
I barely go on dates

All of these are results of my online chess addiction.
However, after all that said, it makes me sad to think that I will give up chess completely. I still want to keep my playing skills and improve.

Can a chess player keep himself in shape only by studying chess (which is not as addictive as playing online) and playing long time control OTB tournaments once in a while? Or should I quit chess completely?

Please help me by finding some things that I could do to stay good at chess while not playing online.

Edit:

I'm mainly addicted to blitz, the problem is that I lack self control to retain myself from playing it. I tried a few times to stop playing blitz only but failed to accomplish and went back to my bad habits. I wish there was an option to open an account that would be allowed to play long time control games only to help people like me. Once I play blitz I usually just crave to reach a specific rating and I play like am possessed.

I started playing in a local chess club a few months ago. I already got to play 3 long time control tournaments, quite sucessfully and I want to keep my level there. I fear that without this abusive online playing my abilities OTB will be damaged

I'd like to start with this comment of yours:

"I fear that without this abusive online playing my abilities OTB will be damaged."

I know where you are coming from, because I've been there, too. I used to be ridiculously addicted to chess - and I wasn't even very good lol. Now it's a hobby, which is much more healthy.
I also know that fear you speak of - I, and people like myself (which presumably includes you) strive for depth, rather than breadth in life. Being very good at one thing seems so much more important than being kind of good at a lot of things; trouble is, I picked the wrong thing.
Personally, I had to completely stop playing chess for a while. When I came back to it (in a more recreational fashion), I was indeed worse at chess, and though I have improved, I'm still not completely back to where I was (although I strongly suspect I'll get there).
It was completely worth it.
I had free-time. I had sleep. I had better grades. By golly, I even had more friends - not fair-weather friends, but honest-to-goodness friends that cared about me and my life.
I say all of this to encourage you that even if your playing ability drops off, please don't worry about it. Chess is not your life. Your life is your life. Go out and live it! Study with all of your strength, go on dates, hang out with your friends, work your rear end off and become the absolutely amazing, incredible person that you are - one that's always up for a relaxing game of chess with a friend, of course.

Now for the practical suggestions:

Here are some suggestions for maintaining playing strength while limiting online chess:

Study master games. Seriously, doing this will get you way more chess knowledge than playing oodles of blitz games.

Read some chess books, playing out the games on the board if you wish. These books are almost always entertaining as well as being extremely helpful.

Play casually OTB with some friends, analyzing various lines at a relaxed pace - chat with a friend (or maybe even a date) over a nice, no-pressure, slow game (although if it's a date, make sure that she likes chess first XD).

Visit you local chess club, and play some games there when you're in a good spot with your schoolwork and workplace work.

TL;DR: it really is possible to enjoy chess and have a life.


Deep and accurate analysis required In order to resurrect an old line in the Scandinavian defense I am forced to accept doubled pawns at the side where I have pawn majority. To make things even worse, I reach queenless middlegame, and the endgame is not so far away! Still, my engine gives equality or small disadvantage in sample lines.

I don't have hardware strong enough for this type of analysis, so I ask for deep analysis of the following position:

[Title "White to move"]
[fen "rn2kb1r/ppp2ppp/8/5p2/3PN3/8/PPP2PPP/R1B2RK1 w kq - 0 1"]

I really believe that Black might be able to hold this position with equal chances, but I need strong engine analyzing on strong hardware. If required, break the analysis into sub-variations and post them one by one. You could start with 1.Ng5 as I consider it the strongest move. Move 1.Nc5 can be discarded as I intend to play 1...Bxc5 doubling the pawns, thus removing only advantage White has in this position.

I can wait, there is no need to hurry as I prefer quality over speed ( this should be the part of my opening repertoire ).

Thank you for your time and efforts.

EDIT:

Here is the way to reach this position, added on request by member bof :

[Title "Scandinavian defense"]
[fen ""]

1.e4 d5 2.exd5 Qxd5 3.Nc3 Qe5+ 4.Be2 Bg4 5.d4! Bxe2 6.Ngxe2 Qf5 7.O-O Nf6 $8 8.Ng3 Qa5 9.Nge4 Nxe4 10.Nxe4 e6!? 11.Qf3 Qf5 12.Qxf5 exf5

Please focus on the diagramed position in your comments / answers, I do not seek help with the opening moves. They are added here just because member bof asked for them. Thank you.


Is there a database of endgame positions with known perfect play? Perfect play as in, it leads to checkmate in the least moves possible. Not just forced mates.

Yes, it is call Lomonosov table : link

It is all the positions with 7 or less pieces and the whole answer is known.


Stalemate or checkmate? I have a rook, a queen and my king while my opponent has only 2 pawns and a king left.
The situation is complicated because they cannot move anything, except for a single pawn move. But if they move that pawn their king is checked by my queen. Is this situation stalemate or checkmate?
8/8/8/6rk/8/5qPK/7P/8 w - - 0 1

If the situation is as in the diagram below, it is stalemate. You correctly noticed that white has no legal moves: any potential move would put the white king into check, which is not allowed. Furthermore in the position the white king is not attacked, so it is stalemate (not mate).

       8/8/8/6rk/8/5qPK/7P/8 w - - 0 1


Communication with Stockfish engine via Python I try to access the Stockfish engine via Python, but only get bestmove = a2a3.
If I enter the same commands into the MAC-terminal, the engine calculates the correct move.
Can anyone help me, please ?

My Python code is:

p = subprocess.Popen('/Applications/TigerJython/LuChess/Stockfish/stockfish-11-mac/Mac/stockfish-11-64', stdin=subprocess.PIPE,
                     stdout=subprocess.PIPE,
                     stderr=subprocess.STDOUT)

p.stdin.write("uci\n")
p.stdin.write("ucinewgame\n")
p.stdin.write("position startpos moves e2e4 e7e5\n")
p.stdin.write("go infinite\n")
p.stdin.flush()
print(p.communicate())

The result is shown below:

('Stockfish 11 64 by T. Romstad, M. Costalba, J. Kiiski, G. Linscott
id name Stockfish 11 64\nid author T. Romstad, M. Costalba, J. Kiiski, G. Linscott

option name Debug Log File type string default
option name Contempt type spin default 24 min -100 max 100
...
uciok
bestmove a2a3
None

The Problem was p.communicate(), which kills the subprocess. The interaction with the engine works well with the following code:

def put(command, inf_list, tmp_time):

    engine.stdin.write(command+'\n')
    engine.stdin.flush()
    time.sleep(tmp_time)

    if command <> "quit":

        engine.stdin.write('isready\n')
        engine.stdin.flush()

        while True:
            text = engine.stdout.readline().strip()

            if text == 'readyok':
                break

            elif text !='':
                inf_list.append(text)

inf_list = []
put('uci', inf_list, 0)
put('setoption name Hash value 8192', inf_list, 0)
put('ucinewgame', inf_list, 0)
put('position fen rq3r2/2pbppk1/3p1np1/1N5p/1n1PP2P/2N2P2/PP1Q2P1/R3KB1R w KQ - 3 15', inf_list, 0)
put('go movetime=3000', inf_list, 4)
put('stop', inf_list, 0)
put('quit', inf_list, 0)


Is learning opening theory necessary? I have never studied opening theory.  The closest I've gotten was briefly reading about several openings in books, but never memorizing or using any.  While I haven't ever played in tournaments I have played strangers at conferences (where they had tables and chess sets out) several times and never done too badly.

All the questions on this site about opening theory have lead me to wonder:

How important is knowing opening theory and what major advantages would I gain my studying opening theory?

First, let's make a difference between knowing how to play in the opening and opening theory.

You need to know how to play the opening. At first this means you need to know what your goal is in the opening (development, king safety, center control, preventing your opponent from reaching the same) and what that translates to in actual positions. Then you need to have some plan of which openings you want to play, and you must know what the strategic goals of each are, how to play them. Otherwise it's going to be hard to find good moves. After any serious game you should analyze it and figure out what went right and what to do differently next time, and that is true for the opening just as much as for the rest of the game.

On the other hand, opening theory is the almost scientific search for a White advantage. It is about specific lines and once it has been demonstrated that black can equalize in a certain line, opening theory stops being interested. Until the day that someone tries a move that hadn't been considered before and that does lead to a White advantage, until Black's answer to it is found... There are mountains of theory and it's impossible to know it all. If you know a lot of it, and you get it on the board, and it happens to be a line that Black hasn't equalized in yet, you might get an advantage. Which will be useless unless you are strong enough to convert that advantage into a win.

It can be fun to follow opening theory, and if you learn it you can play the first moves like the top GMs do and that is fun, but I don't think knowing a lot of it helps your chess results at all.

For instance, take this position:

[FEN ""]

1.d4 d5 2.c4 e6 3.Nc3 Nf6 4.Nf3 Be7 5.cxd5 exd5

Theory is not interested in this position, as it is a version of the QGD Exchange in which Black has it relatively easy, as he will soon be able to play ...Bf5 and equalize. Books on opening theory will tell you that if White wants to play the Exchange Variation, he should play 4.cxd5 and hold back the king's knight for now.

Sadler in his book on the QGD however notes that it is extremely important to understand positions like this really well, because he used to be beaten in these equal positions as Black again and again "as a young IM". Understanding normal positions is the key to understanding an opening. But they're not interesting to theory.

Let's follow Magnus Carlsen. He played 1.e4 e5 2.Nf3 Nc6 3.c3 a few days ago, the Ponziani. It is generally ignored by theory since Black has many ways to equalize. Then he just played chess, and eventually beat the #5 in the world. That's a lot of hours of studying theory saved.

Work to understand the normal positions in your chosen openings, by playing through instructive games, playing them and analyzing them a lot. Don't memorize theory.


I'm looking for more information on "Goldmann" of the Goldmann Variation (Caro-Kann) I'm working out the Caro-Kann Defense, and I need your help.

In the Lichess study below, I am dealing with the Goldman Variation. I couldn't find out anything about the chess player Goldman, nor could I found useful hints in the web.

[Event "Caro-Kann Defense Study-Goldman  Variation"]
[FEN ""]

1. e4 c6 2. Nc3 d5 3. Qf3 dxe4 (3... e6 4. d4 Nf6 5. e5 Nfd7 6. Qg3 c5)    (3... Nf6 4. e5 Nfd7 5. d4 e6 6. Qg3 c5 7. Nf3)  (3... d4 4. Bc4 e6 5. Nce2 c5   6. d3 Nc6 7. Qg3) 4. Nxe4 Nd7 (4... Nf6) 5. d4 (5. Ne2 Ngf6 6. N2c3 g6) 5... Ndf6 6. c3

Can anybody point me towards more information about Goldmann?

Warren H. Goldman wrote a book titled "New Ideas in Old Settings: Q-B3 against the Caro-Kann". It was published by Chess Ltd. (December 1979). It's still available from Amazon, and perhaps other sellers.

In Kaissiber No. 15 (Summer 2000), there was a thirty-page article about the "Dispute of Theoreticians" on the Goldman Variation (1.e4 c6 2.Nc3 d5 3.Qf3) and its exponents.


Possible chess positon after X ply? I've started to code my own little engine recently and am now working on a perft function which simply sees how many moves there are.
Trying to get correct results I searched online for the correct amount of possible positions after e.g. 4 moves.
Now according to these sources:

https://youtu.be/6Y_FaQhqX2c?t=5m46s

It should be 197281 possible positions after 4 moves, and I can reach that in my code!

But switching a bit around in my code to get some optimization which seemingly shouldn't change anything, I get a different number: 197742
Now I would think that is wrong but I have found different sources again, claiming that is in fact correct:

https://youtu.be/Km024eldY1A?t=5m33s

So, which one is it? 197742 or 197281 possible positions after 4 moves?
I was a bit uncertain whether this belongs here or on StackOverflow.
I went with this one, I hope that's alright.

EDIT: apparently I can't post more than two links due to my low reputation
I'll post the links in comments

Thanks in advance
Folling

The chess programming wiki is correct:

  https://chessprogramming.wikispaces.com/Perft+Results

197281 is the number. I remember I used Stockfish to generate the same number while debugging my code.


Would it be offensive to a chess coach to hire another titled player just to play training games with? Say I have a chess coach, but I hire another titled player to play training games with. Would it be offensive or alright to do? Or they would they care as long as I'm paying them?

You are the customer, therefore you can spend your time and money as you see fit.

From your coaches' point of view, they would prefer it if you didn't use the services of another player. After all, any professional who is paid on an hourly basis would prefer to have a monopoly on a revenue stream and work 100% of the hours that you are paying for. But that is your coaches' problem, not yours.


Can you move from one side being checked to other side in stalemate? I am not a chess player but I have a homework where I have to code a chess program. I would like to know if it is possible for a player's piece to be in check, the player to move out of check, and in turn put the other player in a stalemate, from just one move?
For example: White is in check -> White moves out of check -> Black is stalemated
I haven't found any examples of it so far, but I also haven't found anything saying it's never possible, so if anyone can say either way that would be great!


Has the 50 move rule been used in serious games? There are a lot of questions about the 50-move rule; details on how to claim the draw, why the number 50, etc...

But the most interesting question seems to be whether the rule has ever been applied in an actual game! (N.B. I am referring to serious sanctioned games only). To be more concrete:

  Is there any official game between FIDE masters or above which ended in a draw as a result of one of the players invoking the 50-move rule?

Yes, many times. Ivanchuk- Kamsky 2009 is one example, but there are hundreds if not thousands of others. Ushenina - Girya 2013 made some news recently because Ushenina couldn't mate with knight and bishop in time.


How to build a good opening repertoire? I am struggling to build a good opening repertoire. I have tried a few chessable courses. None of them have worked. My opponents counter my opening pretty easily. What is the best way to build a good opening repertoire? My openings for black are the Modern and the Dutch and my opening for white is the London System?

Expanding on RemcoGerlich's comment...

Beginners often overestimate the importance of opening theory. If your rating is below around 2000 or even somewhat above) it is perfectly possible to get by with a very rudimentary knowledge of opnenings. It is unlikely that you lose many games because of the opening. All of your mentioned openings tend to go for closed positions and are not full of tactics or traps that you can fall into. It is much more likely that you lose for other reasons than lack of opening repertoire.

Much more important is being good at tactics and having a good positional understanding, knowing the typical plans in certain pawn structures. The first part tactics is easy to train by repetition solving puzzles. The second aspect (positional understanding( is harder and requires time. I recommend to read through annotated games or (nowadays) watch commented games of which you find plenty on chess24, chess.com, youtube, etc.

Once you have a decent understanding of plans and positional play, learning openings will make much more sense because you will understand why a certain move is  made and also what to do if your opponent makes a non-standard move that is not in your repertoire.

Most definitely you don't want to learn openings by heart without understanding the ideas behind them.


engines keep playing same game Just finished writing customizing a chess engine by basically adding a bitboard to the freely availably tscp engine. Now I'm testing it out in winboard and notice that often the two machines will play the same game multiple times in a match. I'd like to add some variety to the games by at least having it pick equal moves at random. I'm just using alpha-beta search with simple move ordering. I'm thinking about just adding a small random number to the leaf nodes to break ties but I don't really like this solution because some of the smaller bonuses that the evaluation function uses are 3-5 centipawns. So I don't have enough "room" for random number to break the ties.

my other thought was to have the engine pick randomly which move to keep when it found an evaluation == alpha. I don't really like this because I suspect it favors moves ordered last in the search.

Question is how can I pick from the equal scoring leaf nodes randomly? and also evenly?

Note:

It's a good idea for your engine be deterministic. There is no reason to select a move randomly. You would only do it to lower your engine strength. If you make your engine non-deterministic, you will find it very hard to debug and reproduce a bug. My recommendation is not to do it.

You shouldn't modify your engine. You may want to use an opening book, and pick a line randomly. Many chess GUI can do that, for example, the CuteChess software. Arena GUI can do also that.

But if you insist:

Let's take a look at the Stockfish source code.

 Move Skill::pick_best(size_t multiPV) {

    const RootMoves& rootMoves = Threads.main()->rootMoves;
    static PRNG rng(now()); // PRNG sequence should be non-deterministic

    // RootMoves are already sorted by score in descending order
    Value topScore = rootMoves[0].score;
    int delta = std::min(topScore - rootMoves[multiPV - 1].score, PawnValueMg);
    int weakness = 120 - 2 * level;
    int maxScore = -VALUE_INFINITE;

    // Choose best move. For each move score we add two terms, both dependent on
    // weakness. One is deterministic and bigger for weaker levels, and one is
    // random. Then we choose the move with the resulting highest score.
    for (size_t i = 0; i < multiPV; ++i)
    {
        // This is our magic formula
        int push = (  weakness * int(topScore - rootMoves[i].score)
                    + delta * (rng.rand<unsigned>() % weakness)) / 128;

        if (rootMoves[i].score + push > maxScore)
        {
            maxScore = rootMoves[i].score + push;
            best = rootMoves[i].pv[0];
        }
    }

    return best;   }

Stockfish starts multi-PV (not supported in TSCP, so you'll need to code it yourself!)
Compute a random number and add it to the score for each PV
Compare each weighted PV, and pick the best one

You may find the following links useful:

Chess programs that mimic some amateurs
How does a chess engine mimic an Elo rating

Recommendation: Don't do it unless you want to weaken your engine.


Is there an online chess game or app that allows for custom setup of pieces? Question arose with a friend when he he posted this picture on his blog.

Is there a game where you could configure a game with the pieces like this? I know it is a bit odd, but he and I suspected it would be a somewhat fun diversion to actually play that board. Obviously you could do it with a physical board, but I usually play online or on my phone.

You can use Xboard/Winboard depending of the OS you have and uncheck the option "Test Legality" at the general options menu, I did it myself with in my Xbord/Linux configuration and this is it:


Is a given time control per side or in total? The Wikipedia page about Chess Time Control describes for example:

  ... 90 minutes for the first 40 moves ...

A move in chess is defined as both White and Black side doing their separate move, so if the 90 minutes are per side, then the Wikipedia description appears to be misleading.

This applies also to the World Chess Championship 2018.

Are these 90 minutes per side, or total ?

Time controls are always specified per side, so White has 90 minutes and Black has 90 minutes, for a total of 180 minutes (for the first 40 moves). See the FIDE handbook:

  6.3.1 When using a chessclock, each player must complete a minimum number of moves or all moves in an allotted period of time including any additional amount of time with each move.

It says 'each player', not 'both players'. It's probably not worded more elaborately since it's 'common knowledge' among competitive chess players.


Effect of chess on work I'm a software engineer, mostly working from home so I get to schedule my time however I want. I noticed few things recently.

If I play more than 3 games a day, I can't work afterwords, I'd be mentally tired. I used to think that Chess makes me more productive and I kept playing every few hours a 5 min match to stay focused, but noticed that if the match is hard to win, I can't focus on work afterwards or if I was in time trouble.

I'm avoiding playing chess these days because of that and considering leaving the game. Is it just me or is what I described a common problem?

I have the same problem, and I think it's caused by two factors:
1- Bad time management.
2- Taking the games (win, loss) and rating seriously.

It happens to me that when I am winning and then I lose on time. I keep thinking of the game, even after I close the app. It's because I keep thinking that I should've played faster here or there. When I lose due to bad position or blunders, or if the position was equal, I run the analysis and keep thinking of the missed chances to win.

I did like what you did. It's been a week or so that I haven't played chess games. I only solve puzzles and do lessons. No online full games. This keeps my mind working (refreshed by the distraction of a different activity) and I don't have to think of what went wrong!


Is there a method or tip to best memorize current enemy pieces' movements? I have started to play Chess again after a few years. It is not difficult to reproduce an opening or sticking with a plan during the middlegame, but the most difficult to me is to keep track of enemy pieces threats on open rows/diagonals/columns.

As an example during one game I've lost track of an open diagonal that has a bishop of the other player and no piece (white or black), and forget to take care of not letting pieces stay on that diagonal unprotected while I was thinking on something else (like a plan to stick with).

My question: Is there a tip or a known method of pros like "memorizing/imagine colors" or create a "mental X mark" inside all those squares that makes part of a enemy movement possibility?

Sometimes I get caught by those pieces that are full aggressive (not protecting anyone)...

What you are talking about is called "board vision". Googling "chess board vision" will get you a ton of stuff.

One thing that may help. On looking at an enemy piece (or one of your own) do not ask "where is it?" but ask directly "what is it doing?". For example, that Bishop is controlling that diagonal, which is annoying because I would like to use some of those squares. The battle for control of an important square might involve pieces close to or far away from that square, but they should be linked in your mind as participants in the same struggle. Psychologists call this chunking. You can remember things about a group of pieces more easily than about the individual pieces.


The Vienna Game: Good, inferior or bad? I have been taking a look at 1.e4 2.e5 2.Nc3, which is known as the Vienna Game. At this point I have become familiarized with a substantial amount of variations and main lines. The principal bifurcation comes on 2...Nf6 or 2...Nc6 by Black, which provides two quite different "systems", since 2...Nf6 allows a strong 3.f4. Apart from this, I have studied quite a number of master games. My overall conclusion is that the Vienna Game is a sound, promising line for the 1.e4 player. It offers positional, strategical struggle in some lines, and sharp aggressive play on others, so players of all styles may find it enjoyable. Of course, Black has the chance to equalize if he knows what he's doing, but in what opening is this not the case?
I then want to ask the opinion of more experienced players than myself: do you consider the Vienna Game to be equally good to other 1.e4 lines, such as the Ruy Lopez or the Scotch? Inferior to them, but still god? Or not even good at all? My question comes from the fact that this opening is hardly ever seen in master play, and it is usually only played on blitz/rapid games as a surprise weapon.

The International Master Gary Lane in his book about the Vienna game wrote in 2000 that this opening "has a long history and a bright future". He added

"in these days of computer databases [already 20 years ago!], opening
theory has become so intense that some variations have been analyzed
to move 30. It is hardly surprising that some 'forgotten' opening
variations have been revived by players to looking into unknown
territory, and the Vienna is a perfect arena for this."

So, if Vienna suits you, if you like the obtained positions, if you know the main theme (e.g. which pieces to swap, which promising pawn structure to get, ...) go ahead!
Here are some stats about the Vienna game compared to others openings in a Big and a Masters database. In the Big one, the Vienna game is the second choice and compared to 2.Nf3 it offers a higher risk (more losses) but also a premium (more gains). The Vienna is the 3rd choice in the Masters database with also a higher variance.

In the Big database

In the Masters database


Why can't a dropped pawn deliver checkmate in Shogi? In discussion surrounding another recent question, the fact came up that a "dropped" pawn in Shogi isn't allowed to deliver immediate checkmate, whereas any other type of piece can be dropped to deliver checkmate. This has gotten me (not a Shogi player at all) wondering why that distinction is in the rules:

  Is there a particular rationale, perhaps coming from the other rules of Shogi, for singling out pawns as being unable to deliver checkmate via a drop?

I found this on the web:

The rule that a pawn can not give checkmate probably stems from the rule that a piece may not be placed in a position from where it is unable to promote or continue. A pawn may only give checkmate by being placed directly in front of the emperor; a position from where it is unable to move or promote. It can not take the emperor piece as it could with other pieces, and it can not be promoted until it moves again.
In Shogi, violating rules such as "Two pawns can not occupy the same column" or "a piece can not be placed in a position where it is unable to move or promote" results in an immediate loss for the one who violated the rule. Thus, by placing a pawn in this location, the player automatically loses the game by violation of a rule. The checkmate that the player gives doesn't matter because it was obtained through the rule's violation.
In certain Shogi variations, such as yari shogi, a pawn can be used to give checkmate.


Recommended software for ICCF play? I am interested in playing correspondence chess online through the ICCF. It is my understanding that using computers is not only allowed, but almost mandatory. My question is: What all kinds of software are needed to be successful, and what are the best software packages to use in each category? I know you need an engine, a database, and some kind of analysis program, but which ones are best? I'd be interested in hearing about both freeware as well as commercial programs.

Thanks for any help!
Chris =)

The best engine to use for analysis is most likely stockfish. Works with multiple procs, probably the strongest tactically. And as a bonus, it's free (but you should get a good UCI. I use Fritz UCI which is ok. An UCI that shows multiple lines of analysis at the same time is kinda mandatory). Imo using  an engine in correspondance chess is only interesting if you're strong enough to understand easily why the program makes the choices he makes. ie 2000+ fide at least. You will also notice some of their evaluation function flaws : for instance overvaluing lines which win a pawn but give opposite color bishops, for stockfish. Also sometimes giving more value to prophylactic moves than line opening moves, when in fact it's better to go for the lines opening immediately (it doesn't always realize how strong it can be because of horizons effects).


A Black setup against White's Hippo Attack If I'm playing as White against the Hippo Defense, I usually go with this setup.
[FEN ""]

1. d4 b6 2. c4 Bb7 3. Nc3 g6 4. e4 Bg7 5. Nf3 e6 6. Be2 d6 7. O-O Ne7 8. Be3 Nd7 9. Qc2 O-O 10. Rad1 h6 11. d5 e5

But I don't know what kind of setup I should have if I'm playing as Black against the Hippo. I found that this formation cannot be achieved. Any suggestions? Note that I start with 1...Nf6 against the Catalan opening because I play Nimzo-Indian/Ragozin against 1.d4.

The best choice is to aim for quick development. Once White has played 8 moves, you would have pushed the d/e/f- pawns forward, developed three pieces, and castled. White is still in the center. Now aim to absolutely wreck White's position with ...f4


Can't a pawn capture onto the last rank to promote? I do not play chess much. Recently a friend reached out to play some online games.   We ran into an odd situation that I cannot find a rule on.
His White pawn was at g2 and my Rook was still at h1. He planned to take the rook with his pawn to promote it, but the game would not allow him to make the move and we couldn't figure out why.
Is there something illegal about that move? There were no underlying issues with the pawn movement that would leave the king in check or something similar.
Addendum-Per the answer below, I asked him about popups getting blocked. He said he had no problem getting the promotion going forward, but was being blocked from taking the rook.

Since the board is mirrored, the pawn is on b7 and the rook on a8. But b7xa8 promoting to a piece is a valid move.
I'm not sure which program/website this is, but it could be that a popup is asking to which piece White wants to promote, and something/your browser is blocking this popup, and your friend cannot complete the move.


Chess.com insufficient material draw I played a game at chess.com and the endgame was KNN vs KP. When the pawn was captured, the server automatically give a draw due to "insufficient material". I am confused about chess.com's insufficient material standard here:

If "insufficient material" means neither player could possibly give checkmate by a series of legal moves, then KNN vs K should not be draw by insufficient material as checkmate is still theoretically possible.
If "insufficient material" means checkmate cannot be forced, then with some rare exceptions, the server should give draws to almost all KR vs KR or KQ vs KQ games, which I have never observed. Similarly by the same principle, many KP vs K game will be automatically terminated as a draw once a drawing position is reached.

So what is the standard here?

Well, simply put, they chose to follow the USCF "Article 14: The Drawn Game rule 14E: Insufficient material to win on time, 14E3: King and two knights."

While it is not a forced mate, there is a mating position that is possible, thus they could have easily followed the FIDE rule, and allowed the side with the knights to continue playing.

It was probably a judgment call, and one that was made so more players would not be put off by having to play easily drawn positions for 50 moves.

I do not know if it is coincidence that you asked this today, but in the 2019 World Blitz Championship just this morning, there was a big to-do concerning Magnus Carlsen and Alireza Firouzja.

The game was up and down, but then Alireza Firouzja had a winning advantage, but in the final position below, the position was theoretically drawn when Alireza Firouzja knocked a piece over, and while resetting it, he flagged. Should it be a draw since Magnus had no pawns, or a win because there is a possible mating position? Well, after an appeal, and the rules were clear, the game was awarded to Magnus.

Here is the final position, and I will show a sample line, no matter how far fetched, that shows the rule in action. THESE MOVES WERE NOT PLAYED.

 [FEN "8/4k3/4P3/3B2P1/4P1K1/8/3b4/8 w - - 0 1"]

 1. Kh5 Bc3 2. Kh6 Bd2 3. Kh7 Bxg5 4. Kh8 Kf8 5. e7+ Bxe7 6. Bg8 Bg5 7. Bh7 Bf6#

The fact that this is even possible, no matter how unlikely, is why Alireza Firouzja lost under the rules. Although this is an unfair example of the rules working badly in a given position, they have to be consistent, and there may be other positions that would not be so unfair. it would be hard in practice to say, "this is OK here, but not there". They have existed in the past, but rules for different positions (like extending the 50-move rule to 100 moves for certain positions) have never worked well.


How to minimise your opponent's fun in a game? I play numerous online chess games and in this question I am self-centred: I play for two purposes:

to win the game, or when winning is unlikely, to draw the game.
to improve my chess skills, which eventually enables me to win/draw more games.

I do not care about my opponents' fun. I do not care if they feel frustrated or bored. However, I will remain polite and I am against bad sportsmanship.

Here is my logic: when my opponent finds a game non-interesting, they will more likely make inferior or aimless moves, or even blunders, and thus increase my chance of winning.

A few thoughts:

When the opponent invites me into a sharp line, decline it. Make moves to solidify my position instead. Decline most gambits.
Choose boring openings whenever possible.
Choose openings that my opponent does not like, if I know their preferences.

Is the idea of destroying your opponent's fun good? Are there any other strategies to bore my opponent so that hopefully they will lose their patience and start making inferior/aimless moves?

I play for two purposes:

  to win the game, or when winning is unlikely, to draw the game.
  to improve my chess skills, which eventually enables me to win/draw more games.

These are good goals, although you might want to add "to have fun" because if you don't have fun you are quickly going to lose motivation.

  I do not care about my opponents' fun.

Also good, because if you care too much about your opponents' fun you will end up losing focus and not follow your two stated primary goals.

  Is the idea of destroying your opponent's fun good?

No, it is counterproductive. If you start focusing on how much fun your opponent may or may not be having then this can only distract you and detract from your game. If, for the purposes of this question you are going to be truly self-centered then you cannot let your opponents' feelings, good or bad, enter into your considerations. It can only lead to bad play on your behalf. Concentrate on making the best moves.


Are there any illegal positions that are difficult to spot? I have a question and I'm sorry if it sounds very uninformed, I'm not a professional chess player so my interest is mere curiosity. I was wondering if there are examples of illegal positions that require more than a superficial look at the chessboard to be recognized as illegal.

All examples of illegal positions that come to my mind are pretty trivial.

A missing king
Two kings of a color
Too many pieces considering possible promotions (e.g. 4 queens + 6 pawns)
Pawns in the first rank
Pawns in the eight rank
All pawns in the second rank and other pieces in higher ranks (except knights)

It's very easy to see that these examples are all illegal. Are there any illegal positions that require more insights to spot?

Yes - the less a position looks like a real chess game, the harder it is to spot if it is illegal or not. Sometimes, retrograde analysis is needed to prove a position can be reached in a legal way. For an example, see the starting position of the Horse Concoction by Harry Goldsteen, which can be proven to be legal.
[FEN "8/7P/1P5B/2B1Q1n1/3nn2P/1PRnk1nR/3nnnK1/2B1nQBn w - - 0 1"]

However, as White's pawns have to have captured at least five black pieces, the same position with an additional black piece is illegal:
[FEN "8/1b5P/1P5B/2B1Q1n1/3nn2P/1PRnk1nR/3nnnK1/2B1nQBn w - - 0 1"]


Practicing against an engine vs practicing over the board? When I initially started playing chess I used books and board. Later, when I started using chess software, I think my game improved a lot for a time, and I got a rating of 2000 at chess.com

But I am now faced with the following problem: when I recently went to a tournament I was completely blank over the board, and I was feeling that this is a bit different.
I was not able to calculate moves.

The question is: how should I maintain balance between engine practice and over-the-board practice?

Engines do not make tactical or blunt mistakes. However, their calculation range is given by their predefined strength.

People behave differently. In general, their game is rather stable. But they can make big mistakes, or on the contrary, excellent moves, when you don't expect it.

Also, when playing against people, there is a certain level when psychology comes into account. Stress is generally higher than against an engine, which won't feel any emotions when playing against you.

That's one beautilful part of the game too, emotions are confronted. Good players know how to keep control.


Beginners question: The double pawn Question: Are there rules of thumb that every chess player should know about the double pawns?

Bad: They can't defend each other like adjacent pawns can.

Good: They give you an extra open file for your rooks.

Usually the bad outweighs the good, but there are a zillion exceptions. Most beginners are overly afraid of having doubled pawns.


Is the 50-move rule ever used in grandmaster games? The 50-move rule states that if no capture or pawn move occurs for 50 consecutive moves, then either player may claim a draw. It seems like the 50-move rule is never truly necessary to determine that a game between two sufficiently competent human players is drawn. I know that there are forced checkmates that involve sequences of moves much longer than 50 (I was reading about a mate in 545), but none of these could be found and played by a human within any reasonable time control.
Do games between GMs ever actually end because of the 50-move rule, or do they always agree to a draw long before this is necessary?

Yes, sometimes the 50-move rule comes up in grandmaster play. One recent example that comes to mind was the game Ushenina-Girya (Geneva 2013), in which the reigning women's world champion failed to convert a knight-and-bishop checkmate within the required 50 moves, and the game was drawn. So this is a case where it's a theoretical win, but the stronger side couldn't put it away quickly enough. I would imagine there are some similar examples in the rook-and-bishop vs. rook ending.

[fen ""]
[Event "Women Grand Prix Geneva"]
[Site "Geneva SUI"]
[Date "2013.05.06"]
[EventDate "2013.05.03"]
[Round "4"]
[Result "1/2-1/2"]
[White "Anna Ushenina"]
[Black "Olga Girya"]
[ECO "D11"]
[WhiteElo "2491"]
[BlackElo "2463"]
[PlyCount "251"]

1. d4 d5 2. c4 c6 3. Nf3 Nf6 4. Qb3 dxc4 5. Qxc4 Bf5 6. g3 e6
7. Bg2 Nbd7 8. O-O Be7 9. e3 O-O 10. Rd1 Qc7 11. Nc3 Bg6
12. h3 Rad8 13. Qe2 e5 14. e4 exd4 15. Nxd4 Rfe8 16. Bf4 Qc8
17. Be3 Bb4 18. f3 Qb8 19. Bf2 Bh5 20. Qc2 Bd6 21. Nce2 Bg6
22. a3 h5 23. b4 Ne5 24. Qb3 Nxf3+ 25. Nxf3 Nxe4 26. Nh4 Nxf2
27. Kxf2 Bh7 28. Nf3 Re7 29. Ra2 Rde8 30. Rad2 Bc7 31. Nfd4
Bb6 32. Qf3 Qe5 33. Kg1 a5 34. Kh1 axb4 35. axb4 Qg5 36. h4
Qh6 37. Nf4 Re3 38. Qxh5 Rxg3 39. Qxh6 gxh6 40. Nh5 Rg6
41. Re2 Rxe2 42. Nxe2 Kf8 43. Bh3 Bc7 44. Bf5 Rd6 45. Rxd6
Bxd6 46. Bxh7 Be7 47. Nhf4 Bxh4 48. Bf5 Ke7 49. Nd3 Kd6
50. Nc3 Kc7 51. Kg2 Kb6 52. Kf3 Bf6 53. Ne4 Be7 54. Bc8 Kc7
55. Bg4 Kb6 56. Nec5 Kb5 57. Nxb7 Bxb4 58. Nxb4 Kxb4 59. Nd8
c5 60. Nxf7 c4 61. Ke2 Kc3 62. Kd1 Kb2 63. Nxh6 c3 64. Bf5 Kb3
65. Bc2+ Kb2 66. Nf5 Ka1 67. Ne3 Kb2 68. Nd5 Ka1 69. Ke2 Kb2
70. Kd3 Kc1 71. Ba4 Kb2 72. Nxc3 Ka1 73. Nd1 Ka2 74. Bc2 Ka1
75. Kc3 Ka2 76. Bb3+ Ka1 77. Ne3 Kb1 78. Nc2 Kc1 79. Ba2 Kd1
80. Nd4 Ke1 81. Kd3 Kf2 82. Bd5 Kg3 83. Ke3 Kg4 84. Be4 Kg5
85. Kf3 Kf6 86. Kf4 Kg7 87. Kg5 Kf7 88. Kf5 Kg7 89. Bd5 Kh6
90. Ne6 Kh7 91. Kf6 Kg8 92. Nf4+ Kh8 93. Be4 Kg8 94. Nh3 Kh8
95. Ng5 Kg8 96. Nf7 Kf8 97. Bh7 Ke8 98. Bf5 Kf8 99. Nh6 Ke8
100. Nf7 Kf8 101. Ne5 Kg8 102. Ng6 Kh7 103. Be6 Kh6 104. Bg8
Kh5 105. Ne5 Kh4 106. Kf5 Kg3 107. Bc4 Kf2 108. Kf4 Ke1
109. Ke3 Kd1 110. Bd3 Kc1 111. Nc4 Kd1 112. Nb6 Kc1 113. Na4
Kd1 114. Be4 Kc1 115. Bd3 Kd1 116. Nb2+ Kc1 117. Nc4 Kd1
118. Bg6 Kc1 119. Bf5 Kd1 120. Nb6 Kc1 121. Na4 Kd1 122. Nb2+
Kc1 123. Nc4 Kd1 124. Kd3 Kc1 125. Kc3 Kd1 126. Bd3 1/2-1/2