How do I learn to understand the middlegame?

In principle, the middlegame is indeed just raw calculation. In principle, the entire game of chess boils down to only that. But since the space of possible move sequences is so vast, chess is of course too complex from the standpoint of pure calculation for that to be all that we do when we play. And after all, even our computational superiors (chess engines) need to be guided with built-in positional understanding in order to play a good game of chess.

So yes, if you're feeling fairly comfortable with your grasp of calculation and the execution of tactical operations, but often find yourself "not really sure what [you] just did," then it does sound like positional understanding is what you need to accrue. A good way to look at things is this: tactics are a means to an end - and at bottom they are the means to all ends in chess - but it's not terribly useful to see tactics as the ends themselves, and that is where heuristic positional knowledge is most useful, as a guide telling you what purposes various tactics should be put toward.

For instance, former champion Vladimir Kramnik described the play of two of his predecessors thus:

  To a certain extent, Smyslov was the pioneer of this style, which was later brilliantly developed by Karpov, i.e. the gradual mounting of positional pressure based on the most accurate calculation of short lines.

Now, regardless of whether you want to play like a Smyslov or Karpov, or more like an Alekhine or Tal, I point to Kramnik's words here just because they bring out this idea of letting positional considerations guide your hand, while your tactical acumen gives you the wherewithal to achieve your aims. OK, so how to acquire positional understanding?

Here there are many many options. You mention chess.com's chess mentor course; I have no knowledge of that, and so have no opinion. I can point you to a couple of books that are designed to begin to steer amateurs toward an expert/master understanding of positional play:

How to Reassess Your Chess by Jeremy Silman. This is perhaps the most widely-known book on the subject these days, and with good reason I think. Silman does a fine job of getting the reader to (1) look at positions through the lens of various types of imbalances - e.g. who has more space, is one side's bishop better than the other's, is one king safer than the other's, etc. - and (2) begin to use those imbalances as guiding factors in determining what your plan/goals should be - e.g. I have two bishops against two knights, so I'd like to open up the position to make use of the bishops' long-range power.
The Giants of Strategy by Neil McDonald. This book is less systematically instructional than Silman's, but it is still instructive. McDonald looks at examples of play from Kramnik, Karpov, Petrosian, Capablanca and Nimzowitsch in chapters grouped around positional themes (e.g. the seventh rank, outposts, pawn breaks, planning). This isn't an overly advanced book, and is probably well-suited to the same audience as Silman's. I wouldn't recommend this book alone for gaining positional understanding, but I think it can act very nicely as a supplement to Silman, say.


How to write a simple chess engine to statically evaluate a position?

Why can't you just make a Winboard chess engine, but evaluate a position statically??

You will need to follow the Winboard protocol:

  https://www.gnu.org/software/xboard/engine-intf.html

Although everybody uses alpha-beta/nega-max pruning, but Winboard doesn't know your code. All you need to do is just give an evaluation score from your static function.

Your "engine" will wait for the go Winboard command. Print thinking output like:

  ply score time nodes pv

where score will be your static evaluation score. Your engine doesn't need to make a move, Winboard will wait forever for a move. You can always setup a new position in Winboard.


Where can I find free training tools like detailed annotated chess openings, middle games and endgames in the PGN format?

You can have a look a chess.com forums where people share a lot of PGN games.
pgnmentor.com offers PGN sorted with openings, middle game themes and endgame themes. If you are looking for an all in one platform, chessbase is the best so far, a bit expensive but will serve you well.


In general, it is better to be an exchange (rook vs. minor piece) down than a minor piece. If you look at the standard table for piece value, you see that being an exchange down is only 5-3 = 2 points, while being a minor piece down is 3 points.


Where to download chess master games(pgn format)/databases for android for free?

http://www.pgnmentor.com/files.html

Allows you to download by player, by opening or by event where the game was played.


What relative point values of pieces do engines use?

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

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

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


So I grab a rook instead. Did I break a rule?

No, the FIDE Laws of Chess are very clear. The choice of piece is not decided until it touches the promotion square.
In so far as touch move applies to promotion the key is that the promotion must be performed with one hand. That is the same hand must be used to remove the pawn from the board (it does not have to be first moved to the promotion square) and to place the promotion piece on the board. How the piece reaches the "moving hand" is irrelevant. It may be transferred from the other hand. If a piece is captured in the act of promotion it must be removed also with the same "moving hand".

4.4 If a player having the move:
...
4.4.4 promotes a pawn, the choice of the piece is finalised when the piece has touched the square of promotion.
...
4.6  The act of promotion may be performed in various ways:
4.6.1 the pawn does not have to be placed on the square of arrival,
4.6.2 removing the pawn and putting the new piece on the square of promotion may occur in any order.
4.6.3 If an opponent’s piece stands on the square of promotion, it must be captured.
,,,
7.5.4 If a player uses two hands to make a single move (for example in case of castling, capturing or promotion) and pressed the clock, it shall be considered and penalized as if an illegal move.


You seem to get the meaning/importance of tempo a bit wrong - it's not about getting back to the old square, it's about losing one move during the process, thus forcing the opponent to make his turn when it puts him in worse situation (this is called Zugzwang). This is especially important in endgames, and you can see some examples in the same wiki article you are referring to.

Also note that the final square doesn't have to be the same as the starting one (e.g. Re1-e2-e3 instead of Re1-e3), although it often is (mainly in Kings' triangulation). Knight cannot do any of that, as mentioned in answer by @magd. Knight can just jump from and back to the same square, but the opponent can e.g. also do some repetitive move and you end up right where you started. Knight just cannot take the route to its' destination which will lose exactly one tempo (or any other odd number).

But all other pieces (even pawns if they are at their starting square) can take an extra move while going to the destination, which in many situations enables you to force the opponent to make a move when it's a bad time for him. Triangulation is a classic example of this tactic.

Generally speaking, losing tempo or just getting back to the previous square is usually bad in openings or even middlegame, although that depends on the situation. But in the endgame, deliberate loss of tempo is often maneuver which wins you the game (of course, if situation requires so).

An example from wiki:

[fen "8/1p1k4/1P6/2PK4/8/8/8/8 w - - 0 1"]

If black would be on the move in this position, it would be clear victory for white, as after black King moves away, white can proceed either with his King or his Pawn (depending on the move). But white is on the move, so he must think of a way how to make it work. The answer is, lose a tempo with triangulation:

[fen "8/1p1k4/1P6/2PK4/8/8/8/8 w - - 0 1"]

1. Ke5 Kc6 2. Kd4 Kd7 3. Kd5

And now black is on the move, which enables white to break through.

You are right in saying that loss of tempo is used "only" to put opponent in zugzwang, but the importance of this is greater than it might seem at first. For example, every classic mate endgame uses loss of tempo and zugzwang to get the opponent's King to the edge of the board and to mate him. You often use zugzwang without even realising that you used it. Look at the mate with Rook:

[fen "1k6/7R/2K5/8/8/8/8/8 w - - 0 1"]

1. Rg7 Ka8 2. Kb6 Kb8 3. Rg8#

You aim to get your King to b6 when black King is on b8, so you can mate with Rook on 8th row. But you can't do that right away, as after 1. Kb6, black would get away with Kc8, and 1. Rh8+ would enable black to get away with Ka7. So in the process of getting to 8th row with your Rook, you deliberately lose a tempo with 1. Rg7 in order to win the game.

In contrast, to address your original question, Knight is not able to do that:

[fen "8/8/8/8/8/7p/5K2/5N1k w - - 0 1"]

1. Ng3+ Kh2 2. Nf1+ Kh1

If white could just get to the starting position with black on the move, it would be a quick victory (1... h2 2. Ng3#), but Knight can't lose a tempo, so it's impossible, which is why this position with white to move is a draw.


Is a pawn still backward if other pieces can defend it?

According to Wikipedia:

  "...it is a pawn that is behind a pawn of the same colour on an adjacent file and that cannot be advanced without loss of material, usually the backward pawn itself. In the diagram, the black pawn on the c6-square is backward."

  "Pieces can become weak when they are devoted to protecting a backward pawn, since their obligation to defend the pawn keeps them from being deployed for other uses."

So it is still a backward pawn if it is protected by another piece. Perhaps it is protected, but now it has become a burden on a more valuable piece.

The backward pawn creates an obligation upon (and therefore decreases the value of) whatever piece is defending it. There is a penalty if the piece defending the backward pawn moves elsewhere (loss of the pawn).


What are the biggest events in chess by viewership?

Please note, this does not answer the question, but I find this information gives some helpful clues. This is twitch daily viewerships of all chess channels combined for the past 5 years. It shows peak and average daily viewers. But it doesn't say what the events were corresponding with the heightened figures.

Source: https://sullygnome.com/game/Chess/1825/summary


Cocking the gun tactical motif (preparing a discovered attack)

In Dutch, the two attacking pieces involved in a discovered attack (or the two defending ones in a pin, which is basically the flip side of a discovered attack) are called 'kopstuk' and 'staartstuk', literally translated 'head piece' (the black bishop) and 'tail piece' (the black rook). Preparing a discovered attack like this is called 'staartstuk plaatsen', literally translated 'putting the tail piece in place'. I think it has been coined in the official Dutch method for teaching chess which has been used widely since the 1990's, so many younger and middle-aged players here know the term.
I'm not sure if there's even a well-established (let alone official) English terminology for the 'tail piece'. Wikipedia doesn't mention it. Perhaps 'hidden piece' makes sense? Then you'd be 'putting the hidden piece in place', but as you can see, this is far from being official. I like your own phrase better.


Best way to use UCI engine to play against itself

I don't think it's a good idea to write a new framework. You should use Cutechess. CuteChess is free, stable, fast and reliable.

I'll answer your questions anyway:

You should not clear the hash, it's the engine job to fill it and replace it
You don't have to send FEN, you can also give a move list
By default, multipv is 1 so you don't need to do anything


I would assume such pawns have always be valued somewhat higher (generally) by chess engines since they were around. Doing so follows from rather basic heuristics, that weak engines long ago could have followed:

1) Controlling important squares. Taking the example of the e6-pawn (for the points below as well), it controls the f7- and d7-squares.

2) Potentially blocking in enemy pieces. If Black's bishop were still on f8 then it would have to come out via ...g6 and ...Bg7. Black's major pieces are also prevented from fighting for the e-file.

3) Conversely, White's major pieces have free reign over the e-file.

Of course, sometimes a pawn on the 6th rank could prove to be a weakness. But if it's protected enough, usually the benefits are clear.


How to solve this puzzle of Martin Gardner?

According to the FIDE Laws of Chess:

1.4 The objective of each player is to place the opponent’s king ‘under attack’ in such a way that the opponent has no legal move.
1.4.1 The player who achieves this goal is said to have ‘checkmated’ the opponent’s king and to have won the game

That means that if white has a knight which is 2 normal knight moves away from the opponent's king then the opponent's king is in check, under attack.
Then consider white starting the game like this:
[fen ""]

1. Nc3 null 2. Nb5

Then you can see the black king is in check. On the knight's next move it can go Nb5-d6-e8. But there is no way for black to get out of check. Hence it is checkmate.


Is the TSCP chess engine able to run on a 32 bit processor?

Although pretty much everything even a mobile phone runs on the 64 bits, there is no reason why TSCP can't be run on a 32 bits architecture. In fact, it was written before 64 bits became common. TSCP can be run on any architecture as long as you can compile it, there is no platform-dependent code.

Bitboard is simply a 64-bits integer, that doesn't mean you can't use it on a 32-bits machine. Your machine would need at least an extra instruction cycle to transfer a 64-bit integer on a 32 bit machine, but everything still works.


Is there any analysis of the Carlsen-Caruana World Championsip match by AlphaZero?

Yes, there is: AlphaZero on Carlsen-Caruana Games 1-8 and AlphaZero on Carlsen-Caruana Games 9-12. We don't have seen the PGNs with their concrete lines so far.

I'm not sure how helpful that is. Just one minute thinking time … seems to be a bit short. Some deeper calculation might be more valuable.


Understanding Kh1 and Be3 in the King's Indian Defense Bayonet Attack

I found the games, and you have to take them with a grain of salt since one was between a 2150, and someone who was not even FIDE rated. The second was between two 2360's, which I find a bit suspicious. I am going to post that second game.

I can tell you the basic ideas behind each move, but I am not sure that they were strung together in an optimal manner. This whole line is pretty rare, and as of Ng8, there is only one GM game in Mega2020.

The idea behind:

Ng8 - The knight is not well positioned on e7, so it is going to g8-f6-h5 to join in the attack. In addition, it will over protect the Bg7 should it go to h6 in an attempt to trade off the bad bishop.
Kh1 - To make room for the Be3-g1 maneuver, which did not happen in these games, in an attempt to avoid the potential trade of the Be3 for the Bg7 (after Bh6).
In both cases, in the game below, the Qe1 and Bf2 were to overprotect the g3 square since a Nh5 often sacrifices itself there, and it can be incredibly dangerous. Based on this common idea, I do not think that Kh1 fit in with this position.

Here is one of the games with the maneuvers you mentioned.

 [Event "Paks Atom Cup GM 1st"]
 [Site "Paks"]
 [Date "1996.??.??"]
 [Round "?"]
 [White "Vukanovic, Sasa"]
 [Black "Molnar, Bela"]
 [Result "0-1"]
 [ECO "E97"]
 [WhiteElo "2360"]
 [BlackElo "2360"]
 [PlyCount "108"]
 [EventDate "1996.09.??"]
 [EventType "tourn"]
 [EventRounds "13"]
 [EventCountry "HUN"]
 [EventCategory "7"]
 [FEN ""]

 1. Nf3 g6 2. c4 Bg7 3. e4 d6 4. d4 Nf6 5. Nc3 O-O 6. Be2 e5 7. O-O Nc6 8. d5 Ne7 9. b4 Nh5 10. c5 Nf4 11. Nd2 f5 12. f3 Kh8 13. Nc4 Ng8 14. Kh1 Nf6 15. Be3 N6h5 16. Qe1 Nxe2 17. Qxe2 f4 18. Bf2 Rg8 19. cxd6 cxd6 20. Nb5 Bf8 21. Rfc1 b6 22. a4 Ba6 23. Nc3 g5 24. b5 Bc8 25. a5 Rb8 26. axb6 axb6 27. Na4 g4 28. Ncxb6 g3 29. Rxc8 Rxc8 30. Nxc8 gxf2 31. Qxf2 Qxc8 32. b6 Be7 33. Qb2 Qd7 34. b7 Rb8 35. Nc5 Qc7 36. Ne6 Qc4 37. Kg1 Nf6 38. Rc1 Rxb7 39. Rxc4 Rxb2 40. Rc7 Ng8 41. g3 fxg3 42. hxg3 h6 43. Rd7 Kh7 44. f4 Kg6 45. fxe5 dxe5 46. d6 Bf6 47. Rc7 Rb6 48. Rd7 Kh5 49. Nc7 Rb7 50. Kf2 Kg6 51. Kf3 h5 52. Ke3 Nh6 53. Kd3 Nf7 54. Kc4 Nxd6+ 0-1

The only GM game from 13...Ng8, so you can see how they played it.

 [Event "Gashimov Memorial 3rd"]
 [Site "Shamkir"]
 [Date "2016.05.28"]
 [Round "3"]
 [White "Safarli, Eltaj"]
 [Black "Mamedov, Rauf"]
 [Result "1/2-1/2"]
 [ECO "E97"]
 [WhiteElo "2664"]
 [BlackElo "2655"]
 [PlyCount "55"]
 [EventDate "2016.05.26"]
 [EventType "tourn"]
 [EventRounds "9"]
 [EventCountry "AZE"]
 [EventCategory "20"]
 [FEN ""]

 1. d4 Nf6 2. c4 g6 3. Nc3 Bg7 4. e4 d6 5. Nf3 O-O 6. Be2 e5 7. O-O Nc6 8. d5 Ne7 9. b4 Kh8 10. c5 Nh5 11. Nd2 Nf4 12. Nc4 f5 13. f3 Ng8 14. cxd6 cxd6 15. Be3 Bh6 16. a4 Bd7 17. Nb5 Bxb5 18. axb5 fxe4 19. fxe4 Nxe2+ 20. Qxe2 Rxf1+ 21. Rxf1 Bxe3+ 22. Qxe3 Nf6 23. Qh3 Nxe4 24. Qg4 Nf6 25. Qe6 Ne4 26. Qg4 Nf6 27. Qe6 Ne4 28. Qg4 1/2-1/2


What was the biggest chess tournament held in the world?

According to the USCF, the record holder for largest attendance at a rated chess competition is the SuperNationals V with 5335 participants. Link

The SuperNationals III also had over 5000 participants, so this must be the recurring tournament that brings in the most people.


Is there a name for this common type of blunder?

It is probably a bit more general than what you describe, but one move blunders are often called (a case of) "chess blindness".

I'm not a hundred percent sure, what exactly happened in you're case but often people make the second move of a combination (or variation) first, because they are ahead of the actual position. But I don't know a succinct term for that.

If you listen to top players post game interviews, what you hear incredibly often is "I just forgot about move xy". I guess if that description is good enough for Aronian and Co, it is good enough for us. ;-)

Another loosely connected term is "residual image". This describes the case when you are calculating and pieces that already moved, are still on their original square in your mind.


Taking into account your earlier version of this question (with number of moves to think ahead, etc), I think you might be a bit confused about the terms. Basically chess is played using two methods:

tactics/calculation
positional play/strategy

Tactics/calculation

... is when you actually calculate concrete variations, i.e. something like: if I make this move, my opponent does this, to which I reply with this move, etc. When playing chess, in most positions you don't need to calculate very deep: perhaps 3 moves or less, or not at all. This is because most positions are rather quiet and you have a number of equally good moves available. Trying to calculate deep here would quickly exhaust your memory (e.g. if at each move you have say 3 possible moves to consider, then you already have 27 variations if you calculate 3 (half)-moves deep). Of course there are also positions where you need to calculate deep (say 10 moves), but if it is some forced line with few alternative candidate moves, it is not all that hard to do so.

Anyway, there are situation, where pure calculation does not help and you need another method to come up with moves, which brings us to...

Positional play/strategy

.. this is based more on intuition, experience, general principles and is much harder to train than tactics/calculation. To start with, you should familiarize yourself with common positional motifs. Don't need to learn all of them at once, but start with some easy important ones like "piece activity", "open file/file control", "king safety", "isolated pawns", "good pieces/bad pieces".

When playing a game of chess, try to take into account these factors, e.g. think what pieces are badly placed, check whether you can occupy an open file, etc. This will lead naturally to meaningful plans. If you run out of plans, learn a new positional motif and see whether this helps.

In the opening/middle-game, the plan is often determined by the pawn structure and you can read about it in: the wikipedia article

The tricky part comes, when you have several positional motifs available and need to decide for one or the other. For instance, is it a good idea to go for a pawn storm, if this neglects my king's safety?

In order to train such positional ideas, ideally, you have a stronger player look over your games and point out strategical mistakes (or compliment you on your strategical play). Another option is to read or watch annotated games and see what plans they develop in different types of positions. Learning this plan making will take time and many games in order to gain experience on what works and what does not. But don't worry, for most beginner games, tactics/calculation is much more important than long term strategy.


What are the common themes in the Catalan?

I have played the Catalan for something like 25 years, and to me the big secret explaining the opening's popularity is the following: You can expect a massive score against weaker players.

The key strategic factors in a successful Catalan are:

1) You achieve control/dominance over all four central squares, something rarely seen in other openings. (By the way this explains why the Catalan set-up isn't so effective with a black bishop on f5; white has too little control over e4.)

2) Long-term pressure against black's queenside, in part exerted by the bishop on the diagonal. In the end something is going to break.

These factors make it possible to turn up unprepared for a game Sunday morning during a weekend tournament and have a winning position before the first cup of coffee. In other words, great opening!

For books that focus on philosophy and not too much on concrete moves I can recommend the series How Wojo won.


Very interesting indeed. Although French, Philidor was in London for some time and virtually all the listed subscribers are clearly English, and book first edition is 1749 when he was there. It appears he played regularly at the St James Chess Club. The English were fond of clubs for a long time.
Here's a Wikipedia article with useful information:
https://en.wikipedia.org/wiki/Fran%C3%A7ois-Andr%C3%A9_Danican_Philidor
And here's a page directly to the point:
https://www.pascalbonenfant.com/18c/clubs/jt_chessclubs.html
As to when the first club started, I have no idea. It's a topic worth researching.


How do I to convert tarrasch-base.tdb into pgn for scid?

The Tarrasch Chess GUI is an open source, free Windows download. It uses a proprietary database format and the author approached Mark Crowther, the brains behind TWIC to ask if he could use Mark's database of games. Mark agreed but part of the way Mark makes his living is by selling his full database. There is an export to pgn format function in TCG but to protect Mark's work this feature is limited to 10,000 games.
So, provided your tdb consists of fewer than 10,000 games you can download the program, import the tdb database and then export as pgn. If, on the other hand, you are trying to rip off Mark Crowther's database you are SOL (out of luck). If you are determined to deprive Mark Crowther of his dues for developing his database then your best bet is to download the TCG source code, extract the code for pgn extraction and modify it.


Analysis of Pawn Endgame from Amateur to IM

White will be able to force the black King away and make progress.

Something like 8.Kd6 Kf7 9.Ke5 Kg6 10.Ke6 Kg7 11.Kf5 Kf7 12.g6+ Kg8 13.Kg5 Kg7 14.Kxh5


When was it possible for a player's king to be attacked by 3 of the opponent's pieces?

In my thread on the English Chess Forum, which seemed to make the world go crazy on the subject, I gave all the major and minor events in the history of the “legal” triple check that my extensive research has uncovered. This loophole was even talked about recently in Episode 20 of "The Chess Pit" at the 12:13 mark. Here is all information in chronological order.
The dubious phrasing in FIDE's laws of chess goes back to the 1984 FIDE Chess Congress when it is was implemented. This is indicated by its first appearance in the 1985 laws-many thanks goes to @Stephen for pointing this out in a comment. Here is the 1985 law on check in whole. (All linked laws come from the Chess Arbiter's Association website.)
"ARTICLE 9. CHECK
9.1 The king is in check when the square it occupies is attacked by one or two of the opponent's pieces; in this case the latter is or are said to be "checking the king."
9.2 Check must be parried by the move immediately following.
9.3 If the check cannot be parried, the king is said to be "checkmated" ("mated"), (See Article 10.1.)
9.4 Declaring a check is not obligatory."
Beforehand, the 1980 laws instead stated "The king is in check when the square it occupies is attacked by an enemy piece." This itself is as vague since it can interpreted to allow a king to be left in double check. However, since double check is widely known to be possbile,  such an arugement obviously wouldn’t stand. Even so, it is no wonder then why they later rephrased it to "one or two” for clarity. But that still wasn't enough, as the saga of the “legal” triple check shows.
Within a few years, at least some people had realized the implications of the law’s wording. This is evidenced by a letter sent by Robert Norman, who is from Dar Es Salaam Tanzania, to "CHESS Magazine", then called "Pergamon Chess,” that was published in the June 1988 issue. This is the oldest known chess problem that utilizes the "loophole."
[Title "Robert Norman, CHESS Magazine June 1988, White To Move And Win"]
[FEN "1n5k/1r6/5K2/4Q1Pb/8/8/8/8 w - - 0 1"]

1. g6 Nd7+ 2. Kf7+ Nxe5++ 3. g7+! Kh7 4. g8=Q+ Kh6 5. Qg7#

Thanks to Jonathan Bryant on Twitter, we have a visual of Norman's letter.

The chess magazine EG reprinted it April 1989, saying this about it: "Definitely an oddity. Ridiculous, irrelevant, amusing or disturbing, as the reader chooses."
Of course, it is arguable as to whether or not it can actually be considered legal. It can be countered that triple check is indeed accounted for in the letter of the law. The aforementioned EG magazine summarized it neatly: **"The argument is that check by three men is not check. Well, one can easily counter that check by three men includes check by two and is therefore covered (not 'specifically excluded') under the Laws, which do not need to be changed." Even under the counterargument, the idea of the triple check alone was enough of an ambiguity to change the law's wording,  which definitely says something about it.
Norman’s problem is a online rarity online, so here are a few links to it.
1- A Dutch blog for bizarre chess problems.
#2-An obituary for Robert Norman.
#3-Page 29 in the 12/2001 issue of Internet træk.
A few years later in 1992, the idea again appeared in CHESS Magazine, then called Maxwell Macmillan Chess, in the column "Addicts Corner" by Richard James and the late Michael Fox. I found the relevant part of the February issue in an old Google forum.
"CHECK THIS OUT!
Right, N. Short, J. Speelman, J. Nunn, and the rest of you clever clogs. Break your heart on this: White: Ke3, Qb2, Ne5 Black: Kh8, Re8, Rg8, Ba7, Nb6, Pg7, h7 Black incautiously played a double check 1...Nc4+?? How did White crash through to victory? Admit it; you're baffled. Deduct one hundred Elo points [and read on]:
Dead easy. White gets out of check by 2. Nf7 mate. Yes, it's perfectly legit. Consult Article 9.1 of the laws: "The King is in check when the square it occupies is attacked by one or two of the opponent's pieces..." It says nothing about a threefold attack, so White's move takes him out of check..."
[Title "Kevin Thurlow, CHESS Magazine February 1992"]
[FEN "4r1rk/b5pp/1n6/4N3/8/4K3/1Q6/8 b - - 0 1"]

1... Nc4+ 2. Nf7#!

It seems that Thurlow's problem spread like wildfire, and FIDE finally got wind of it. This is similar to what Tim Krabbe's joke castling problem did. In a short time, the wording was soon changed to the modern wording at the 1992 Fide Chess Congress for the 1993 laws-"The king is in "check" when the square it occupies is attacked by one or more of the opponent's pieces"
You can find various references to the subject in the English Chess Forum. Most are by Kevin Thurlow in reference to his problem, and some others are by Stewart Reuben, who is an English arbiter who has on the rules commission and helped fix the wording after its 1992 rediscovery.
In conclusion, from 1985, when the effect of the 1984 FIDE Chess Congress change took place a king could hypothetically be left a in a “legal” triple or higher check in a FIDE rated game until 1993 when the law was again rephrased at the 1992 FIDE Chess Congress.
Additionally, this caused some effects on chess composition other than Norman's and Thurlow's joke. There exists a chess variant called ”Bosma Chess" that was created in 1993 by Dutch problemist R. Bosma that is based on the "loophole." Bosma also noticed the odd wording of FIDE laws, after it was changed in 1992, so he incorporated it into fairy chess.
In Bosma Chess a king is not in check if it is attacked three or more times. If a king is triple checked, it can't be captured. Here is an example problem that utilitizes underpromotion to get the point across.
[Title "Henk Le Grand, 1st Price 151th Thematoernooi Probleemblad 1993, Mate In 2, Bosma Chess"]
[FEN "7K/1NRNkP1R/5p2/b1P2B2/2n5/8/8/3q4 w - - 0 1"]

1. Rc8! null (1... Bd8 2. f8=R#) (1... Qxd7 2. f8=N#) (1... Nd6 2. f8=B#) 2. Re8#

Finally, fast forward to 2008, 30 years after Norman's problem was published, a variation of it appeared in an obscure and now dead blog called "Far Off Chess." that was created by  IM Jens Kristiansen. In a post entitled "In the twilight zones of chess rules", which is about old and new ambiguities in the rules, Kristiansen created a version of Norman's study from his hazy memory. It is as beautiful as the original and worth showing.
[Title " Jens Kristiansen, Far Off Chess 12/13/2008, White To Move And Win"]
[FEN "7k/rn6/5KP1/p1p4b/8/8/8/7R w - - 0 1"]

1. Kf7 Nd6+ 2. g7+! Kh7 g8=Q+ Kh6 4. Qg7#

This is the known history of the "legal" triple check. Whether or not you would consider it legal, the idea was and still is an amusing nitpick at the exact wording of the FIDE laws of chess.

In the comments, @bof has discussed the effects of the triple check, which was only lightly discussed in the English Chess Forum. This section will supplement that discussion.
When triple checked, kings become normal pieces that can castle. Under the 1984-1992 laws, castling into, out of, and through check along with having adjacent kings is legal. However, the main interest is about king captures, which are not forbidden either. The answer is simple-if a king is captured, that side can't be checkmated. This is the only possible conclusion going strictly by the law's letter. This is different from Bosman Chess's immune kings.
Here are problems of mine that show these bizarre conclusions.
Castling Into Check
[Title "Me, chess.stackexcange.com 6/15/2020, Mate In 1"]
[FEN "8/8/8/8/8/7n/5Rrp/2k1K2R w K - 0 1"]

1. O-O#

Castling Out Of Check
[Title "Me, chess.stackexcange.com 6/30/2020, Mate In 2"]
[FEN "4r3/4N3/8/b7/5pp1/3P1Bkp/2n5/2N1K2R w - - 0 1"]

1. Nf5+ Kxf3 2. O-O#

Castling Through Check
[Title "Me, chess.stackexcange.com 8/12/2020, Mate In 2"]
[FEN "8/8/8/5B2/5p1Q/5kn1/2NRb2n/31K2R w K - 0 1"]

1. O-O+ Nhxf1 (1... Bxf1 2. Rf2) (1... Ngxf1 2. Qf2#) 2. Qg4#

Adjacent Kings
[Title "Me, English Chess Forum 6/13/2020, Mate In 1"]
[FEN "8/8/8/8/8/3p4/3rp3/RK1kN3 w - - 0 1"]

1. Kc2#

Lastly, here are some bonus problems.  On page 3 of in my English Chess Forum thread it was asked if a quadruple check could be done, which I did, but I later managed a quintuple check!
[Title "Me, English Chess Forum 4/30/2020, Mate In 4, Dedicated To Marken Foo"]
[FEN "1RnkBB2/2p5/8/4K1Nr/4N3/6R1/1n5q/bQ2r3 w - - 0 1"]

1. Qd3+! Nxd3+ 2. Ne6+ Kxe8 3. Nf6+ Kf7 4. Rg7#

Per another request, I also showed a triple check via en passant.
[Title "Me, English Chess Forum 6/13, Mate In 2"]
[FEN "3r4/3B3N/4n3/3K1k1P/2pp2p1/3r1bP1/2Q1PR2/8 w - - 0 1"]

1. e4+! dxe3+ 2. Bxe6#

Lastly, as suggested by @supercat in a comment, here is a mate in 1 that removes two checks for mate.
[Title "Me, chess.stackexcange.com 6/13/2020, Mate In 1"]
[FEN "8/7B/3B2NK/8/5k2/6P1/5Q2/8 w - - 0 1"]

1. Ne5#


Why is it funny to say Giri played the Evans Gambit?

The joke is based on the perception of Giri as a very solid, "drawish" player. There always seems to be one top player who is the butt of such jokes. It used to be Leko, nowadays it's Giri.

Take a look at this reddit thread for example or this chess24 April's fool.

The swashbuckling Evan's is the last opening Giri would ever choose to play, or so the jokester suggests.


Is there a site that provides (legal) online access to free chess books?

Open Chess Books is a site that aims to “republish classic chess books, with all diagrams transformed in animated boards, and release them for free.”

They only have two books at the moment (Modern Ideas in Chess and Chess Fundamentals), but it's a great resource so far.

Predator at the Chessboard by Ward Farnsworth is a great primer on chess tactics that's available to read for free online or purchase in print form.


Looking for sound files from a VERY old version of Chessmaster Live

Let me suggest another way.

You are assuming that the game had sounds in the form of files that are reusable. This may not be the case.
But why not start searching for files yourself with search terms like mp3 chess pieces (or chess pieces sounds or sound effects chess moves, or other variations)? These will lead to e.g.:

Soundsnap board game sounds (not free)
Sound Hills Chess Pieces and Board sounds (not free)
Pond5 Chess piece sound effects (not free)

The rest is left as an exercise to the reader ;-)

I found that chess.com actually has a question about this as well.

Any of these may good enough for you.


How does lichess rating compare with chess.com rating?


Why is the rook worth 5 points while the bishop is only worth 3?

You need to understand that the point system is only a rough guideline meant to assist you in evaluating positions or in deciding on potential exchanges. Many factors, particularly the pawn structure, influences how valuable pieces are. Rooks tend to be better in open positions with fewer pieces/pawns on the board, bishops can get hindered in closed positions by pawns of the same color ("bad bishop"), etc.

Despite of all this, the 5/3 values for rook/bishop (or the piece valuation system in general) is surprisingly reliable.

A rook is generally more valuable than a bishop because:

it can reach all squares of the board, while a bishop can stay only on squares of the same color
it can mate in KR vs K, while you cannot win KB vs K.
it covers more squares (can always move to 14 squares on an empty board independent on where it is placed, while with a bishop it can vary between 7 (corner) and 13 (center) squares)

The exact values "5" and "3" are basically found from experience and since there is a bit of a drawing margin in chess, the exact values don't really matter.

One notable and very common exception to the rule is found in many (beginner's) opening play where a bishop and knight can be exchanged for a rook + pawn on f2 or f7. In these cases almost always having two light pieces is better even though you exchange 6 pawn units for 6 pawn units.


Why isn't there a big advantage in this position for black?

Here's a variation from Stockfish.  What we see is that after the smoke clears, Black's advantage actually is pretty small.  Here's why:

If we just 'added up points', which is not a bad way to get an immediate feel for a position, we'd see White is down a single pawn, 13 vs 14.
We also notice White has two pawn islands of two pawns each.  Black has two pawn islands but one of his pawns is isolated.  This is a slight advantage for White. Further, if Black connects his two-pawn island, his King will be completely exposed.  In reality, all of Black's pawns are isolated and will have to be defended by pieces.
Black's King is exposed; with White's Queen on the board any mistake could lead to a perpetual check.
Black's Bishops obviously can't protect each other.  Given the exposed Black King, any of Black's pieces could be picked off by a Queen fork.  Black will have to be very careful to ensure he doesn't lose material to the rampaging Queen.

Items 3 and 4 will make it hard for Black to go on the offensive.

[fen "r1b2r1k/1pq3bp/8/3Qp2n/1P1n1pp1/2NP2P1/3BPPBP/1R2NRK1 b - - 0 0"]

1... Qxc3 2. Bxc3 Nxe2+ 3. Kh1 Nxc3 4. Qb3 Nxb1 5. Qxb1 f3 6.Qc1 fxg2+ 7.Nxg2 Bf5 8.Rd1 Be6 9.Kg1 Nf6 10.Qc7 Nd5 11.Qxb7 Rab8 12.Qa6 Rb6 13.Qa5 Rxb4 14.Ne3 Nxe3 15.fxe3 Rfb8 16.Qc7 Rb1 17.Rxb1 Rxb1+ 18.Kf2 *


Practice makes perfect. I've seen several different ways on how to capture pieces. It's not really something that you learn, but more like something that goes automatically. So, just try it a few times at home (without thinking, so it goes automatically), and do what feels the most natural.


What is the purpose of 3...a6 in the Ruy Lopez?

Playing ...b5 later is not bad for black. Playing it immediately isn't so great, but Black almost always plays ...b5 at some point (unless White plays Bxc6 first!).

The main reason to play ...a6 early is that you can now play ...b5 any time you want to if you decide that you don't White to take the knight on c6. If you don't play ...a6, and then later decide that you want to kick the bishop away and start by playing ...a6, White can go ahead and play Bxc6. If you've already played ...a6, you can go straight to ...b5 and White doesn't get a chance to capture your knight in response.


What sense does promotion to queen make?

In the original form of the game from which chess probably derived, chaturanga, there was no piece named "Queen".

The Queen of modern chess probably derived from a piece named "General": in the beginning this piece could move 1 square only diagonally, then its movenemt became more and more similar to the modern Queen. But there's more: in chaturanga there were pieces very similar to pawns, "Soldiers", that could become Generals after having reached opponent's King field.

When chess was imported in Europe, during Middle-Age and Reinassance, passing especially through Spain, pieces were renamed in order to give european players a more comfortable playing background. For example, the uncommon "Elephant" became "Bishop" (a very well known figure in catholic regions). And the General became the "Queen". But they only renamed pieces without changing the mechanic of the game. Thus, a "Soldier" could (and can) still be promoted.


At this point, I believe white is completely lost, and it seems that the engine agrees. I think the basic idea is that the material deficit is too much and the black king isn't in any real danger as the bishop on c4 can come into g7 and block any checks/mating ideas. While the white king is in the open with active black pieces around it.
Firstly if you take the rook (Qxa8), then Qc4. You can block any checks with the bishop and create a discovery check, which will lead to a checkmate.

You can't really protect the c-pawn well and if you do, it will be too slow as black has very quick ways to infiltrate with the queen. And for similar reasons, it is also not feasible to play defence, as you have too many weaknesses to cover
.

Trading queens also doesn't get you anywhere, although it is recommended by the engine since black's queen is more dangerous than white's. In that case, if you take back with the rook (Rxd7) then Bg7 again and black's rook is always going to keep an eye on the pawn. If pawn takes, then Bf6 and the square is always covered enough times. Not to mention that black can always sack a piece for the pawn and will still be up a minor piece.

Having said all that, although the game is lost for white in all situations, I think your best practical bet would be to take the rook on a8 and sort of hope that black is not able to find the checkmate. As counterplay, you can try to push your past pawn or get your rook on offence with a check.
Hope this helps!


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

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


Are there any examples of high-level games in which the game was resigned or drawn without any captures?

Wikipedia says that the longest decisive game without a capture is:

Nuber-Keckeisen, Mengen 1994 lasted 31 moves without a single capture. In the end Keckeisen, facing imminent checkmate, resigned:

[Fen ""]

1.e4 b6 2.d4 e6 3.Bd3 Bb7 4.Nf3 g6 5.O-O Bg7 6.Nbd2 Ne7 7.Re1 O-O 8.Nf1 d6 9.Qe2 Nd7 10.Bg5 Qe8 11.Rad1 a5 12.c3 Rc8 13.Ng3 Kh8 14.Qd2 Ng8 15.h3 e5 16.Bc2 h6 17.Be3 Rd8 18.Nh2 Kh7 19.f4 f6 20.Qf2 Ne7 21.Rd2 Rh8 22.f5 g5 23.Bd1 Rb8 24.Bh5 Qf8 25.Ng4 Ba6 26.Red1 b5 27.b4 a4 28.a3 Bb7 29.Rd3 Nc6 30.Bg6+ Kg8 31.Qa2+ 1-0

For a drawn game:

Filipowicz-Smederevac, Polanica Zdroj 1966 was drawn in 70 moves under the fifty-move rule, without any piece or pawn having been captured (Whyld 1986, p. 124).

[fen ""]
[Event "Rubinstein Memorial 4th"]
[Site "Polanica Zdroj (Poland)"]
[Date "1966.08.25"]
[Round "14"]
[White "Filipowicz Andrzej (POL)"]
[Black "Smederevac Petar (YUG)"]
[Result "1/2-1/2"]
[ECO "C00"]
[WhiteElo "2330"]
[BlackElo "2450"]
[Annotator ""]
[Source ""]
[Remark ""]

1.e4 e6 2.d3 Ne7 3.g3 c5 4.Bg2 Nbc6 5.Be3 b6 6.Ne2 d5 7.O-O d4
8.Bc1 g6 9.Nd2 Bg7 10.f4 f5 11.a3 O-O 12.e5 a5 13.a4 Ba6 14.b3
Rb8 15.Nc4 Qc7 16.Kh1 Nd5 17.Bd2 Rfd8 18.Ng1 Bf8 19.Nf3 Be7 20.h4
h5 21.Qe2 Ncb4 22.Rfc1 Bb7 23.Kh2 Bc6 24.Na3 Ra8 25.Qe1 Rdb8
26.Qg1 Qb7 27.Qf1 Kg7 28.Qh1 Qd7 29.Ne1 Ra7 30.Nf3 Rba8 31.Ne1
Bd8 32.Nf3 Rb8 33.Ne1 Bc7 34.Nf3 Rh8 35.Ng5 Bd8 36.Nf3 Be7 37.Qg1
Bb7 38.Nb5 Raa8 39.Na3 Ba6 40.Qf1 Rab8 41.Nc4 Bd8 42.Qd1 Ne7
43.Nd6 Bc7 44.Qe2 Ng8 45.Ng5 Nh6 46.Bf3 Bd8 47.Nh3 Ng4+ 48.Kg1
Be7 49.Nc4 Nd5 50.Nf2 Bb7 51.Nh3 Bc6 52.Qg2 Rhc8 53.Re1 Rc7 54.Re2
Ra7 55.Ree1 Ra6 56.Re2 Rba8 57.Ree1 R8a7 58.Na3 Ra8 59.Nc4 Nh6
60.Na3 Nf7 61.Nf2 Rd8 62.Nc4 Rb8 63.Nh3 Bd8 64.Na3 Ra7 65.Qh1
Bc7 66.Qg2 Rd8 67.Qh1 Nh6 68.Ng5 Qe8 69.Kh2 Rd7 1/2-1/2


How do I make the right move after an opening?

Usually each opening consists in a middle game plan rather than just a sequence of initial moves. This means that the criteria behind choosing this or that other opening must be driven by the specific middle game positions that one wants to achieve or is confident to play (driven by personal taste, skills or whichever other reason).

There are mainly two ways to develop sense of positions for middle game:

studying the opening thoroughly: this means taking a book written by experts on the subject analysing positions very deeply until the endgame. Classical openings (Ruy Lopez, Queen's gambit, Sicilian, King's Indian) are easy to play but extremely hard to master, therefore one cannot really play them without extensive knowledge (unless you want to fall back into your previous case, where players end up moving pieces randomly after a while)
looking at classical games by classical players: this is the evergreen advice but really it does help to understand what to do. Good players are such because they have a sense of how to treat specific positions and come up with sensible plans for the initiative. In general looking at GM games helps understanding how to convert small advantages into winning positions (at the end of the day, chess games are not won by throwing all your pieces at the opponent's King, rather by accumulating small advantages throughout the game and converting the resulting endgame position).


Have any tournaments considered a draw to be a loss for both sides?

Never heard of. A few thoughts:

As we all know :-), chess is a draw.
win 3/draw 1/loss 0 tournaments do exist (same rule idea, less drastic).
In Swiss tournaments, I say this would be an invitation to even more "Swiss gambit" (although evidently you can't overtake in the last round, as all scores are integer)
It's also pointless for an 1:1 match, thus it probably could be tried only in a round robin.
Just for fun, I applied your proposal to a random GM round-robin: Candidate 2020. The ranking did not change much. (But that is obviously no argument, since they would have played differently.)
Evidently, you need even more fine scoring (and could use the standard one, naturally...)
The proposal would suit hazard play: Why not throw in a possibly incorrect sacrifice? You don't lose much if it doesn't work.
Coda: Might be worth an experiment.


How can I get informed if a titled chess player will be holding a simul?

Generally, you should belong to a club if you wish to play titled players in simuls. The more active your club is the more likely the club is able to do, which includes paying titled players to host simuls.

Other than that, you could consider hosting the event. Simply contact titled players on sites like chess.com and the ICC to see if they're interested. They'll usually charge a fee, and off you go.

Sometimes titled players host simuls at tournaments as well, so it would do you well to find out what tournaments are near you or that you can attend. If you're in the US, then both USCF and FIDE are good for finding upcoming tournaments. Outside the US and you'll want to stick to FIDE as well as other national federations to find chartered/sponsored tournaments.


It's quite surprising how few opening books for playing the Ruy Lopez as white there are, given that it's one of those lines that have a claim of being "the main line of chess".

Greet's Play the Ruy Lopez is from 2006. Shaw's Starting Out: the Ruy Lopez from 2003. Khalifman had the Ruy Lopez in his Opening for White according to Anand series but it was very detailed, very high level and is also getting old.

Doknjas' Opening Repertoire: The Ruy Lopez was published last year, so it is easily the most recent white report in the Ruy. The writer is an FM, I have no idea how good of a writer he is. Here is a review at the BCF site.

But my vote goes to McDonald's Ruy Lopez: Move By Move for a first book on the Ruy.

Because it is very focused on the ideas of the opening, and it has a plan for how you should start playing the opening: first you play safe lines based on an early d2-d3, which are fine and played by the world top, and then later when you want to you can expand into more and more complex lines by playing d3 later in the game, or never. So it contains two repertoires in the closed Ruy, one with d2-d3 and one aiming for d2-d4.

Only if you are substantially stronger than 2000 OTB, already understand the structures and want ambitious concrete up to date theory, then I would get Doknjas as it is very recent.

And if Parimarjan Negi ever finishes the Ruy Lopez repertoire for Quality Chess he is writing, then that probably becomes THE book for strong players immediately.


I find watching the latest generation of self-taught AIs play is incredibly exciting - and of course they are relatively opaque as is much of AI these days.
Maybe openings turn out to be relatively tractable in that there are not so many fundamentally sensible options, given the transpositions which are possible. A player who begins with a few garbage moves however may still be able to utterly overwhelm a weaker adversary through superior midgame play. So the answer is it depends how much damage the AI inflicted on itself.
The midgame is where the real innovation of alpha zero seems to be. Particularly the received wisdom about pawn play has been turned on its head: pawn sacrifices can be powerful to win tempos and to clear space for line-moving pieces. Surely new concepts like this must already be a factor in top-level human analysis now.


Can anyone explain the motives of this chess engine?

The engine is only looking ahead one move. Most of these blunders are giving check, but are poorly constructed. It seems that the engine is programmed to think that giving check is always good, but does not check to see if its pieces are defended.


Does anyone know of unusual and fun chess tournaments around the world?

The Chess Train tournament is an 11-round rapid tournament that is held on a moving train. In five days it travels from Prague to Prague, visiting different cities each day. This year it goes to Poland, including Warsaw and Krakow.

Each day the train travel is from 10:00 to 14:00, with the two rounds of rapid during that time; the afternoon and evening are then free for sightseeing.


Why are the corner pieces referred to as "rooks" in English?

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?


Why didn't Giri go for the pawns against Ding Liren (Tata Steel 2015)?

When I saw the live broadcast yesterday I was sure he would go for the knight sacrifice. And I still think he probably intended to. It is in no way counterintuitive, I think it is rather the obvious candidate for a winning continuation.

But of course a knight is a knight and the queening of one of the white pawns is still some ten moves away. He probably tried to work it out completely to the point where black has to give his rook and the ending is beyond any doubt one hundred percent winning, and after 68 moves of an extremely hard fought game he just couldn't do it.

And in the end, instead of wasting any more time, he decided to play it save. So my take on this is that tiredness and the irrational fear to overlook some miracle save lead to a more practical decision.


What is the point of delaying the exchange in the Rossolimo?

The underlying reasons for delaying BxN are -

Preserving options
Saving tempi

Suppose in the final position black plays a6 forcing white to make a decision. Bf1 is a perfectly good alternative to BxN. It is one which will lead to an entirely different game, one which white may prefer.
In any case it makes some sense to wait for black to commit with a6 because then BxN comes without the loss of a move that playing it unprovoked would involve and it has provoked a weakening of the b6 square.
Again looking at the final position above, an immediate BxN leaves black with a choice of recaptures, either bxc6 or dxc6. White may not like the position after dxc6, in which case it makes sense to wait until black plays d6 first before exchanging. Alternatively white might not like the possibility of BxN bxc6 followed by d7-d5. Again if white waits for d6 then a tempo has been saved.
Keeping options open and saving time are features of the way stronger players play. Prematurely closing down options and squandering tempi are what weaker players do.


The board here looks similar: http://analysis.sesse.net


In this puzzle, why does white play dxe5?

It is quite pointless analyzing moves in lost positions.

Here in either line white will lose a bishop for a pawn.

A queen threat is just that, a threat. Why are you so much afraid of it? The game could continue

... f4
dxe5 fxe3
Qxe3 Nxe5

In the other line you'd have

... f4
Bxf4 exf4

Both are very lost positions.

Why the computer picks the first over the second line, who knows (who cares)? Perhaps it prefers it because the white pieces get slightly more space.

In a practical game, other than resigning, my first choice would also be dxe5 for two reasons:

gives black the chance to blunder with dxe5 after which white can mate starting with Qd8+
it opens the position which gives more chance for swindles for the lost player.


How to proceed in this endgame position?

This is a very common kind of endgame, where you have a pawn majority on one side and fight against a single pawn in the center. Winning this is not difficult, but let's first look at your game...

You

fixed the position of the queenside pawns by playing b6 (to which white cleverly replied b5
ran with your king towards the queenside

Basically you should do the opposite:

keep your king in the center close to the white e-pawn (say around e5, d5, e4 or c4), which white cannot advance
try to create a passed pawn on the queenside: for this you want to start with a6 or c6, not b6.

The idea then is to have that a-b-c passed pawn run,  forcing the white king away from the protection of the kingside pawns

One possible line with comments....

[FEN "3k4/ppp3pp/1b6/8/PP6/4BpP1/5P1P/6K1 b - - 1 1"]

1... Bxe3 { Perhaps not the computer's first choice but a decent practical human decision to turn it into a clearly won pawn endgame. Could perhpas have delayed this exchange to gain an extra tempo (for centralizing the king) since white does not have any good moves. } (1... a5 { Prevents white from playing a5. Objectively the strongest move in the position. The main idea is to keep the white king out of play for as long as possible. } 2. bxa5 (2. b5 Kd7 3. Kf1 Kd6 4. Ke1 (4. Bd2 Kd5 { and white does not get anywhere as the king is bound to the protection of the f2 pawn, black can just collect the a and b pawns or promote the c pawn as he wishes. }) 4... Bxe3 { now is the time to exchange because black will keep the f3 pawn } 5. fxe3 Kd5 6. Kf2 Ke4 { followed by c5-c4-c3-c2-c1Q 0-1 }) 2... Bxa5 { The white king's path to freedom via f1 e1 is now blocked. Black is basically playing king+bishop+pawn vs a single bishop. } 3. h4 { trying to activate the king via h2 } 3... Kd7 { centralizing the king } 4. Kh2 Kc6 5. g4 Kd5 6. Kg3 Ke4 7. Bc5 (7. g5 g6 { the white king has no way to escape and black just pushes the c pawn to c1 }) 7... b6 8. Bf8 g6 { and black will just push the c pawn to c1. }) 2. fxe3 g5 { threatening to create a protected passed pawn on f3. } 3. g4 Kd7 4. Kf2 Ke6 5. Kxf3 Kd5 { First goal achieved: King is centralized. Note that white can never play e4 since after Kd4 white will eventually run out of moves and will have to move the king from the protection of the e pawn. } 6. b5 c6 { or a6 or c5 all will create a passed pawn for black } 7. bxc6 { basically forced because otherwise black would end up with one vs zero pawns on the queenside, which would make his task even easier } 7... bxc6 { Second goal achieved: black has a passed pawn } 8. a5 c5 9. Ke2 Kc4! { Aiminig for the a5 pawn, while keeping an eye on the e3 pawn (which would still be lost after e4 Kd4). Also the black king is threatening to get to d3 after which white would also be lost. } 10. Kd2 { basically forced, because black was also threatening Kc3 after which he'd get to d3 when white runs out of pawn moves } 10... a6 11. Kc2 Kb4 12. Kd3 Kxa5 { Again this is the more human decision. Black could also go for pawn promotion with Kb3 (followed by c4...). It is important to realize that black can catch the e pawn (rule of the square). Also it helps that the lone white king is lost against the a and c pawn (even without the black king's support). } 13. Kc4 Kb6 14. e4 a5 15. Kd5 (15. e5 a4 16. e6 Kc6 17. e7 Kd7 { and the white king is lost against the a and c pawns }) 15... a4 { I am faster than you. Needs to count. } 16. e5 a3 17. e6 a2 18. e7 a1=Q 19. e8=Q Qd4+ 20. Ke6 Qe3+ { and black trades queens and will get a new queen soon on c1. } *


Analysis of a position in order to find the best move

First, your move e5?? was a blunder. 6.Ng5 won a valuable pawn after the forced 6...Be6 7.Nxe6 fxe6 8.Bxe6.

White's opening is not very ambitious when he does not play d4, so you would probably have an easier time getting in the "standard" Sicilian freeing move d5. When black gets that move in, he is usually equal, if not better. So instead of 5...e5??, 5...e6 was better helping to achieve that goal of d5.

In the final position, after 6.Bg5, Be7 looks best, but you already weakened d5 a lot, so in most cases, black will trade on f6, and sink a very powerful knight onto the d5 square.

As you are finding, learning how to play the game does not take long, but learning to play well can take a lifetime (depending on your goals).

 [FEN ""]

 1. e4 c5 2. Nf3 Nc6 3. Nc3 d6 4. Bc4 Nf6 5. d3 e5 (5... e6 6. O-O Be7 7. Bf4 (7. Be3 $4 d5 $1 8. exd5 exd5 9. Bb5 d4 {A typical trap}) 7... d5 8. Bb5 O-O {and it is, as we say, "a position"...black has equalized}) 6. Bg5 Be7 7. Bxf6 Bxf6 8. Nd5


It's definitely a different game when white doesn't close the center and go for the "classical" pawn storming lines.  While those lines are often the easiest to play (black can play f5, f4, g5, g4, g3 without thinking too much), those are also the lines that are arguably the most challenging for black to face.

When white keeps the tension in the center, black has to decide when to break that tension.  Generally speaking, black should do everything possible to develop before playing exd4, as this move nearly always cedes white the entire center.  If black is going to turn over the center to white, it's vitally important to be able to immediately counter attack.  This means that moves like c6, Qc7, and Nbd7 should be played before committing with exd4.  The plan with Nc5 pressuring e4 is often best, but make sure that you can support the Nc5 with a move like a5, preventing b4 chasing the knight away.  The queen on c7 is often useful because it allows the rooks to come to e8 and d8 where they defend the backwards d6 pawn and pressure e4.  Black's plan in these structures is almost always to push d5.  The light square bishop can support this push from e6, but if the white knight stays on f3 then ...Be6 can be well met by Ng5.

In conclusion, these structures are very double edged and black must be precise in order to maintain equality.

When white takes on e5, black usually can achieve a very good game with some precision.  The trick here is to notice that black can use the d4 square, but white can rarely use the d5 square because black can always post the c pawn on c6 and keep pieces out forever.  A common plan is to rearrange the black pieces with Qc7, Rd8, Bf8, and some lengthy maneuver with the f6 knight.  This is often ...Nf6-d7-f8-e6-d4.  The black bishop is frequently left on g7 until the knight has reached d4, and only then is it transferred to the queenside with ...Bg7-f8-c5.

These plans are very common, but they're also topical.  If white is trying to prevent one or more of these re-positioning efforts, then black will have to use tactics in order to justify the moves.

It's very hard to explain quickly, but these plans are usually much easier to play in a long game when you can dedicate dozens of minutes to planning the maneuvers and then carefully execute them.  It's well worth the time investment to play long games with these structures, even if you don't want to make the KID your primary black weapon against 1.d4.


Use of transposition tables in chess engines

Depends on the program and how they implemented it. Many have memorized openings and transpositions later on in the game are usually short enough that the depth of analysis handles it.
Not for me.  But I am old school when it comes to programming.  You may or may not like C++.
Nodes/sec depends on the hardware, opsys, language, and your coding.  The algorithm is far more important for good results.


(For training purposes) Are there any openings with rook pawns that are more effective than others (and if so, what are they)?

Learning good chess principles and playing against clearly dubious openings like 1. a4 or 1. h4 are not mutually exclusive.  In fact, following solid opening principles is the best way to counter weak openings like this.

The moves 1. a4 and 1. h4 are both poor because they do not follow any of the opening principles.  Namely, they do not help control the center, they do not develop or prepare to develop any pieces and they actually reduce the king's options as to which side to castle on by weakening the pawn cover on one side of the board.

To counter such a move, you should simply play normal opening moves.  1... e5 or d5 is a good start.  If white allows it, you can take over the center by advancing the other central pawn two squares as well.  Then simply continue by developing the minor pieces and castling the king to safety.  At this point you will have a large lead in development if white has continued making many foolish pawn moves (which is likely against the type of players who open with 1. a4 or 1. h4) and should be able to make life miserable for the opponent.


Big changes in engine's evaluation after considerable time

This is a complicated position I had in a correspondence game. White to play and win. The engine evaluation rises and falls, occasionally hitting 0 again. Then it stays at roughly 1.5 for a long while until finally finding the breakthrough about 20 minutes in. Unsurprisingly, considering the full line is pretty insane.
[FEN "r5r1/1np3bk/1p1p4/3P4/bpP2PPp/P3N2P/1q1BQ2K/4R1R1 w - - 0 33"]

1. g5 Rge8 2. Qh5+ Kg8 3. Rg2 bxa3 4. Nf5 Rxe1 5. Bxe1 Bc2 6. Nh6+ Kh8 7. Ng4+ Kg8 8. Nf6+ Kf8 9. Nd7+ Ke7 10. Qg4 Nc5 11. g6 Rh8 12. Re2+ Kd8 13. Nb8 Ba4 14. Nc6+ Bxc6 15. dxc6 Qf6 16. Bf2 Re8 17. Ra2 Qe6 18. Bxh4+ Kc8 19. Re2 Kb8 20. Rxe6 Rxe6 21. Qg2 Re3 22. f5 Be5+ 23. Kg1 Rb3 24. Qa2 Bd4+ 25. Kf1 Rf3+ 26. Kg2 Rb3 27. f6 Rb2+ 28. Kf3 Rxa2 29. g7 Rg2 30. Kxg2 a2 31. g8=Q+ Ka7 32. f7 a1=Q 33. f8=Q Qg1+ 34. Kf3 Qd1+ 35. Kf4 Ne6+ 36. Qxe6 Qf1+ 37. Ke4 Qxf8 38. Qe7 Qxe7+ 39. Bxe7


What are some non-functional features of a chess clock that would help choose the best for ones use?

Well I learned way more than I wanted to know about other considerations than mere timing.

This table may be collapsed into a long string of text
someone please edit if that happens

Cost
Size
Accuracy
Precision
Ease of use
Color
Battery Life
Reliability
Ruggedness
Toggle method
maintenance required
Flag display
Analog/digital
Shape
Aesthetic
Ease of setting
Read out type
Safety against accidental reset
Counts moves
Useful for other than chess

Timing variations
 - pre/post add
 - pre/post delay
 - fischer
 - bronstein
 - hourglass - seesaw
 - byo-yomi
 - canadian OT
 - guillotine
 - bonus timing
 - different periods timings

custom settings -MODIFY built in
custom settings NEW
Number of custom settings


What to play vs. 1. d4 when Sicilian is my favorite defense?

You can play the Stonewall defence with black as well, as quid suggested. You can start with a Dutch and get the familiar structure (just an example):

[FEN ""]
1. d4 f5 2. c4 e6 3. g3 Nf6 4. Bg2 d5. Nf3 c6

Or you can play as you have shown and don't have to worry about dxc5 (it actually isn't such a good move):

[FEN ""]
1. d4 c5 2. dxc5?! e6 3. Nc3 (3. b4? a5 4. c3?? axb4 5. cxb4 Qf6-+) Bxc5=

If this variation was your only problem, it should be solved now... :-)

If you don't mind playing Benoni or the Benko gambit I would stick with this variation.


How did the Fried Liver Attack get its name?

From the Wikipedia article on the Fried Liver,

  Italian way of cooking liver ("Fegatello" means to put the liver in a
  net and cook it over a fire, or, in modern times, in a pan. Here we
  can see a metaphor for what happens to Black’s king in this line: it
  is cooked like a "fegatello". Usually Black’s king is caught in the
  mating net and White increases the heat move by move – "dead as a
  piece of liver".)


What are some chess tournaments around the world that have both Grandmasters and non-professionals players in the same section?

I usually find my tournament in this online chess tournament calendar.

If you visit the homepage of a tournament you can often check who already registered and who is eligible to participate.

Another easy way to make sure your conditions are met is just checking the prizes. In Europe a thousand euro first prize usually means there are going to be GMs participating. If there are several thousand euro first prize you can be sure that there will be many GMs and other strong players from all over the world.


What is a good free interface to create and store positions?

If you have a PGN file of those position you could use my site for that. There are already a couple of people using the site not to study openings but have uploaded PGNs of endgame positions to train.
If your PGN software specifies a starting position not inside of a "FEN" header let me know: https://github.com/ArneVogel/listudy/issues/2


Have there been computer-vs-computer chess games exceeding 493 moves?

Tim Krabbe discusses this in his website (see section 328).
It's an old post - dating to 2006 - so it's certainly possible. However 2006 was also a long time ago. Since then engines have gotten more familiar with the rules, and all the top engines I'm aware of are aware of the 50-move rule. 493 moves is very long, but it should still be fairly trivial to get longer games if one just got engines to play and never adjudicate (see example). All one has to do is set some very short time control and play a billion games, and eventually a game will get there.
Games played in tournaments is a different matter, with a necessarily small sample size. In that case I think it's quite likely that 493 moves is the longest on record. It's about 100 moves longer than the next-longest games I'm aware of.
Caveat: the 493-move game wouldn't happen under real tournament rules since the 75-move rule would've been invoked to force a draw.


What are some chess books on openings which include computer analysis?

If I recall correctly, The Wilkes-Barre is Traxler (correct me).

I once analyzed it quite deeply, and the only way white can hope for a win after 5. Nxf7 is 5...Bxf2+ 6. Kxf2 (6.Kf1 is also a tricky draw.) Nxe4+ 7. Ke3.

Or he can simply play 5. Bxf7+ and be a healthy pawn up.

You can do this analysis yourself.


How do I avoid losing to lower rated players?

First, losing is part of chess. If losing didn't suck, then winning wouldn't rock.

Ratings are approximations. Don't let your rating define you.

The way to prevent lower rated players from defeating you is to not allow them to do so. Improve your play such that you can adequately punish the superficial hope-chess moves that "C" players play.

edit - There's no magic wand wand we can wave to help you. There is only working harder so you can play better moves.


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 good to take a fianchettoed Bishop?

There are two reasons for doing this and immediately taking the fianchettoed bishop is not one of them:

Provoke Black into playing BxB when you hope to follow up with Ng5, drive the f6 knight away and then mate on h7
Prevent black from playing h5 until you have been able to play h2-4-5 to pry open the
black king's position.

It can even be worth sacrificing the exchange with h5, Nxh5 Rxh5 to smash open the black citadel.


List of how AlphaZero evaluates openings

You can find the complete table in their paper. See table 2 in the arXiv version linked below:

Mastering Chess and Shogi by Self-Play with a General Reinforcement Learning Algorithm https://arxiv.org/pdf/1712.01815.pdf

How to read them:

The plots show the proportion of times alphazero played a given opening during its self-training games as a function of training time. So e.g., you can see that its interest in employing the French defense peaked after 2 hours, but past that, it abruptly drops to near 0, indicating that after 2 hours+ training it realised the emergent lines from that opening are non-optimal compared to other choices, such as the Caro-Kann defense (which had a promising plateau after 2 hours but eventually dropped too, plot shown below).
Then below the diagrams, you see how it fared against Stockfish in 100 game matches for each line. Finally, alphazero's principal variation for each opening is also indicated below the plots. Please see the table's caption in the paper for any other details.

Overall, the English opening stands out: it kept employing it consistently throughout its training. Ultimately, the pattern suggests a tendency towards more versatile openings.
Caro-Kann diagram from table 2: [Ref]

[Ref]: Silver, David, et al. "Mastering Chess and Shogi by Self-Play with a General Reinforcement Learning Algorithm." arXiv preprint arXiv:1712.01815 (2017)


Why was 20.Qe3 so good in Botvinnik-Sorokin?

First of all, it was played by Botvinnik, a strong World Champion, and one of the most logical players ever, so it clearly has to do more than just let black ruin the white pawns.

It does many things:

It trades off black’s best piece, the active Qc5, and it cannot be
avoided with Qc7? Nxe5!. Trading your opponent's active pieces is very desirable, and I suspect this was the primary motivation for Botvinnik even looking at Qe3.
Despite the fact that those pawns have been weakened, they control
many critical squares. They are also very hard to get at, so
although they may matter in the endgame, black cannot attack them
anytime soon, and other factors will be much more important.
This is a principle that is not seen often, and often missed by
weaker players, but sometimes when you trade down material when attacking,
particularly, trading off a good defender, it allows the remaining pieces to
strengthen, and they become unopposed. In this case, the doubled
rooks are now monsters, and white’s significant lead in development
is going to show even more.
How does black develop the Bc8? In the game, he chose g4 but soon
actually had to strengthen white’s pawns after all.
Lastly, black is going to have a hard time defending e5, and it is
attacked immediately.

The minor weakness, that black can't even get near, was nothing compared to the weaknesses that were exposed when the black queen was no longer on the board to defend them. In short, the Qc5 was the glue that held the black position together, and without it, there was no defense.

 [FEN ""]
 [Event "URS-ch07 Final"]
 [Site "Moscow"]
 [Date "1931.10.25"]
 [Round "2"]
 [White "Botvinnik, Mikhail Moisevich"]
 [Black "Sorokin, Nikolay Tikhovich"]
 [Result "1-0"]
 [ECO "D60"]

 1. d4 d5 2. Nf3 Nf6 3. c4 e6 4. Nc3 Nbd7 5. Bg5 Be7 6. e3 O-O 7. Bd3 c6 8. O-O a6 9. a4 dxc4 10. Bxc4 c5 11. dxc5 Bxc5 12. Qe2 h6 13. Bh4 Be7 14. Rfd1 Nh5 15. Bxe7 Qxe7 16. Rd2 Nb6 17. Rad1 Qc5 18. Ba2 Nf6 19. e4 e5 20. Qe3 Qxe3 (20...Qc7? 21. Nxe5!) 21. fxe3 Bg4 22. a5 Nc8 23. Rc1 Bxf3 24. gxf3 Ne7 25. Nd5 Nc6 26. Nxf6+ gxf6 27. Rd7 Rab8 28. Kf2 Nxa5 29. Rcc7 Rbc8 30. Rxf7 Rxc7 31. Rxc7+ Kh8 32. Bd5 b5 33. b3 Rd8 34. Kg3 f5 35. Kh4 fxe4 36. fxe4 Rd6 37. Kh5 Rf6 38. h3 Rd6 39. h4 Rb6 40. Kg4 Rf6 41. Ra7 Rb6 42. Re7 Rd6 43. Rc7 Rf6 44. Ra7 Rb6 45. Rc7 Rf6 46. Kh5 Rd6 47. Bf7 Rf6 48. Bg6 Nxb3 49. Kxh6 Rf8 50. Rh7+ Kg8 51. Rg7+ Kh8 52. Bf7 Rxf7 53. Rxf7 Kg8 54. Kg6 Nd2 55. Rd7 1-0


Aronian vs Anand World Championship Candidates 2014 Round 8. Is White better after 19.f4.

I am not even close to a decent level in chess, therefore you have to be really skeptical to what I am going to write here. But here is my ~2000 rated opinion:

  Black is not winning after 19.f4, is he?

This is kind of funny to state that black is winning here. This is just 19-th move (so people just went out of the opening), which means that the game just began and most of the previous moves were not actually a real game. Yes, white is a pawn up, but pawn up in the opening does not really counts for too much (mobility of pieces, clear vision of what to do next, preparation of the line, your mood and confidence and many more things should be counted here).

  Why did he choose to draw instead?

No one can tell you except of him. But here are my thoughts:

He already lost to Anand and Anand is a current tournament leader so why gamble and stress yourself in this situation? Having a draw, you secure yourself 5 points which puts you on the same position as a leader. With few possible advantages:

there is no more Anand anymore
you are not stressed and got your points from the game
you have more time to rest, prepare yourself for future games

Also, as you saw from game analysis the position is equal, but unbalanced. Playing the game, you will be really stressed and most probably after additional 1 - 1.5 hours of thoughts you will end up in a draw. Or may be win. Or lose. So why do you need this?

Look at the game Anand vs Svidler in round 7. Both have spend a lot of nerves playing really hard an unbalanced position just ending up in a draw. Approximately 2 hours of hard thought for 2 points. And here Aronian can get them basically for free.


This article may answer your question.

If you want it short:

On average, according to Natalia Pogonina (WGM), the top-3 players in the world earn 1 million / year, top 10 - over 200 000$, top 50 - over 100 000$.

If you want more information, try looking around this thread.


Why are lots of different moves usually considered equivalent in the opening, but not in the middlegame?

For example, after 1. e4 e5 you could play 2. f4 or 2. Nf3, and the computer will tell you they're both top moves in this position without marking either of them as an inaccuracy or a mistake.

That's because there is a line of code in the program which says something like:
If (move is in book) then set move value = accurate
else call regular evaluation function
That line is there to stop the engine from wasting time trying to calculate. Instead it can just look up its book and pick an approved move.

But why doesn't this happen in the middlegame?

Because there is no "book" move. The engine does something completely different from the opening and tries to calculate the best move.

Yet the middle game is the most complex phase of the game, isn't it?

Not really. If there are 30 book moves in a Ruy Lopez Marshall Gambit line then moves 20 through 30 are likely for positions just as complex as for moves 20 through 30 in a different line where book ran out after 15 moves and the engine is calculating instead of looking up. Yet the computer can use its book for the Marshall and save calculating time and effort.

So it's where I'd actually expect lots of moves to be fundamentally equivalent to each other, but instead the contrary happens.

That doesn't make sense. If the engine is calculating each possible different move in a given complicated position then it makes perfect sense for them all to be different.
It is making calculations based on programmed algorithms. It is mot making a human evaluation of the position. The only time different possible moves are likely to have the exact same evaluation is when the engine calculates two different moves out to the exact same final result, like a draw or a checkmate.


Good question. You are right, the Elephant gambit appears to be a dubious opening. Have you checked the wikipedia page on the Elephant Gambit? It offers good lines to fight for an advantage. But they are two other questions:

Do you like to defend or retain the initiative?

Those playing this opening are not afraid to gambit a pawn for the initiative with 1.e4 e5 2. Nf3 d5 3.exd5 e4. In most of the lines following 4.Qe2 Nf6 5.d3 Be7 or 4.Qe2 Nf6 5.Nc3 Be7 white has a pawn up but black has the initiative. With a precise play and a bit of patience, white will gain an advantage.

Do you like opening theory?

The issue is that you are going to face this rare opening once or twice in your tournament life and most of the time black will be better prepared (in this rare line). He/she will have more experience with this gambit. So, another way to deal with this gambit will be to go for an unrated variant such as

1.e4 e5 2. Nf3 d5 3.Nxe5 Bd6 4.d4 dxe4 5.Qe2!?

[fen "rnbqk1nr/ppp2ppp/3b4/4N3/3Pp3/8/PPP1QPPP/RNB1KB1R w KQkq - 0 1"]

followed by Nc3, Bg5 and 0-0-0...

Those continuations have many advantages: Easy to remember; easy to play, and maybe not the kind of positions black are looking for when playing the Elephant Gambit !


How good of a tactical player is Magnus?

You can't be a strong positional player without being a strong tactical player... and you can't be a strong tactical player without being a strong positional player. The two go hand in hand, and when a player is strong they tend to be strong in both domains. Here's one way of explaining this. In order to achieve a good position, you have to see the tactical possibilities on the board. This will let you find good squares for your pieces and activate them. And in order to have tactical possibilities, you need to achieve a good position, as tactics flow from a good position. That's why the two are connected. For someone of Magnus's strength (the best in the world) you have to be extremely strong in both. So, to answer your question, he is extremely strong at tactical chess, positional chess, and endgames.

Another question you might ask is, what is his style? Does he play tactically or positionally? A player's style is largely composed of the positions they have learned and the openings they choose. Historically Magnus has a positional style as he tends to play strategic positions over sharp, tactical ones. However, recently this has changed. In the World Championship against Caruana, he played one of the sharpest openings with black, the Sicilian Sveshnikov. In Tata Steel he reprised this opening. Thus it seems that he is favoring sharp openings with black these days, perhaps out of his desire to win more games and play fewer draws. It will be interesting to see how he plays during the rest of the year. Will he continue to play sharp, unbalanced openings with black? Will he continue to play aggressively with considerable risk? To draw a connection between this question and the one you asked, it's important to point out that Magnus can do this -- switch from a positional style to a sharper and more aggressive style -- because he is so strong both tactically and positionally.

Here is a masterful endgame he played in 2012 which showcases both strategy and tactics. Notice how 38. Kd5 involves a tactic that lets him improve his position, an example of how tactical and positional chess are connected. Another example would be 49. f6.

[fen ""]
[Event "Grand Slam Chess Final"]
[Site "Sao Paulo BRA"]
[Date "2012.10.08"]
[EventDate "2012.09.24"]
[Round "6"]
[Result "1-0"]
[White "Magnus Carlsen"]
[Black "Fabiano Caruana"]
[ECO "C00"]

1.e4 e6 2.d3 d5 3.Nd2 Nf6 4.Ngf3 Nc6 5.c3 Bd6 6.Be2 O-O 7.O-O a5 8.Re1 e5 9.exd5 Nxd5 10.Nc4 Re8 11.Bf1 Bg4 12.h3 Bh5 13.g3 Nb6 14.Nxb6 cxb6 15.Bg2 b5 16.a4 b4 17.Be3 Bc7 18.Qb3 h6 19.Qc4 bxc3 20.bxc3 e4 21.dxe4 Bxf3 22.Bxf3 Ne5 23.Qe2 Nxf3+ 24.Qxf3 Qd3 25.Kg2 Qxe4 26.Bd4 Qxf3+ 27.Kxf3 b6 28.Rab1 Rac8 29.Re4 g6 30.g4 Kf8 31.h4 Rxe4 32.Kxe4 Re8+ 33.Kd3 Re6 34.Be3 Kg7 35.Rb5 Bd8 36.h5 Rd6+ 37.Kc4 Rc6+ 38.Kd5 Re6 39.Bd4+ Kf8 40.f4 Bc7 41.f5 Rd6+ 42.Ke4 Rc6 43.Rb1 Ke8 44.hxg6 fxg6 45.Rh1 Kf7 46.Kd5 Rd6+ 47.Kc4 gxf5 48.gxf5 Bd8 49.f6 Bxf6 50.Rxh6 Be7 51.Rxd6 Bxd6 52.Kb5 Ke6 53.Bxb6 Kd7 54.c4 Kc8 55.Bxa5 Kb7 56.Bb4 Bf4 57.c5 Ka7 58.c6 Kb8 59.a5 Ka7 60.a6 Ka8 61.Bc5 Bb8 62.Kc4 Bc7 63.Kd5 Bd8 64.Ke6 Bc7 65.Kd7 Ba5 66.Be7 1-0

Here's a Sicilian he played as white against Karjakin in the 2016 tie break. He plays a strategic Maroczy bind in the opening but uses a clever tactic to win at the end.

[fen ""]
[Event "Carlsen - Karjakin World Championship Match"]
[Site "New York, NY USA"]
[Date "2016.11.30"]
[EventDate "2016.11.11"]
[Round "13.4"]
[Result "1-0"]
[White "Magnus Carlsen"]
[Black "Sergey Karjakin"]
[ECO "B54"]

1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.f3 e5 6.Nb3 Be7 7.c4
a5 8.Be3 a4 9.Nc1 O-O 10.Nc3 Qa5 11.Qd2 Na6 12.Be2 Nc5 13.O-O
Bd7 14.Rb1 Rfc8 15.b4 axb3 16.axb3 Qd8 17.Nd3 Ne6 18.Nb4 Bc6
19.Rfd1 h5 20.Bf1 h4 21.Qf2 Nd7 22.g3 Ra3 23.Bh3 Rca8 24.Nc2
R3a6 25.Nb4 Ra5 26.Nc2 b6 27.Rd2 Qc7 28.Rbd1 Bf8 29.gxh4 Nf4
30.Bxf4 exf4 31.Bxd7 Qxd7 32.Nb4 Ra3 33.Nxc6 Qxc6 34.Nb5 Rxb3
35.Nd4 Qxc4 36.Nxb3 Qxb3 37.Qe2 Be7 38.Kg2 Qe6 39.h5 Ra3
40.Rd3 Ra2 41.R3d2 Ra3 42.Rd3 Ra7 43.Rd5 Rc7 44.Qd2 Qf6 45.Rf5
Qh4 46.Rc1 Ra7 47.Qxf4 Ra2+ 48.Kh1 Qf2 49.Rc8+ Kh7 50.Qh6+ 1-0

And here's a blitz game he played in 2015. A lot of these moves, including the tactical blows at the end, he played almost instantly. Notice how 19... Bf5 20. Qd2 would lose to 20... Be4 with an unstoppable mate. In a blitz game it's very hard to respond to a move like 19... Bf5. Everything goes downhill after 20. e4 Qxd3. And 24... Bb4 followed by 25... Bd3 is a clever way of saving material after 24. Rd2 put both bishops in a skewer.

[fen ""]
[Event "banter blitz"]
[Site "chess24.com"]
[Date "2015.11.??"]
[EventDate "2017.??.??"]
[Round "?"]
[Result "0-1"]
[White "Jan Gustafsson"]
[Black "Magnus Carlsen"]
[ECO "A96"]

1.Nf3 f5 2.g3 Nf6 3.Bg2 e6 4.O-O Be7 5.c4 O-O 6.Nc3 d6 7.d4 a5
8.b3 Qe8 9.Ba3 Na6 10.Rc1 Nb4 11.Qd2 Ne4 12.Nxe4 fxe4 13.Ne1
Qg6 14.Nc2 Bg5 15.e3 Nd3 16.Rcd1 e5 17.Bxe4 Qxe4 18.Qxd3 Qf3
19.dxe5 Bf5 20.e4 Qxd3 21.Rxd3 Bxe4 22.Rc3 Bd2 23.Re3 Bxc2
24.Re2 Bb4 25.Bxb4 Bd3 0-1


Is there a name for fork-protected pieces?

I agree with asdf regarding the idea that there isn't a name specifically attached to indirect protection of a piece stemming from a fork.

However, in general, pieces that are protected by any tactic, including forking, are said to be "indirectly defended."

As far as a name for the piece being indirectly defended, one might call it a "bait" piece, as it baits the opposing player to make a dubious move. In a specific opening line, there is a somewhat famous "poisoned pawn" - a pawn that looks like it can be taken without fear, but makes things positionally difficult in the long run. Thus, an indirectly defended piece might also be called a "poisoned" piece.


How does AlphaZero learn to evaluate a position it has never seen?

The evaluation function of a chess engine, whether instantiated as a neural net or explicit code, is always able to assign a value to any board position. If you give it a board position, even absurd ones that would never occur in a game, it will be able to spit out a number representing how favorable it is to one player or another. Since the number of board positions in chess is unmanageably gigantic, the training can only occur on an infinitesimal sample of the game tree. The engine is not simply recalling previously calculated values of board positions, but is performing calculations based on the arrangement of the pieces. For a non-neural-net example, part of a chess engine's evaluation might be to add up the value of each piece on its side and subtract the total value of the opponent's pieces. Then, one set of parameter that would be adjusted while training would be the value of each piece.

When the engine is untrained, the values assigned to a position might as well be random since the parameters of the evaluation function start out with (usually) random values. The goal of a training phase is to adjust the parameters of the engine so that it assigns high scores to board positions that are probable winning states for the player.

From the paper on AlphaZero (page 3):

  The parameters of the deep neural network in AlphaZero are trained by self-play reinforcement learning, starting from randomly initialised parameters. Games are played by selecting moves for both players by MCTS. At the end of the game, the terminal position is scored according to the rules of the game to compute the game outcome: −1 for a loss, 0 for a draw, and +1 for a win. The neural network parameters are updated so as to minimise the error between the predicted outcome and the game outcome, and to maximise the similarity of the policy vector to the search probabilities.

[math symbols removed from quote]

In summary, during training, AlphaZero played a game against itself. When the game is over, the result of the game and the accuracy of its predictions in how the game would proceed were used to adjust the neural net so that it would be more accurate during the next game. AlphaZero is not keeping a record of every position it has seen, but is adjusting itself so that it can more accurately evaluate any board it sees in the future.


Chessable offers advanced courses (free and paid). Many of those courses have videos.
https://www.chessable.com/courses/for-advanced-players/


Can one feasibly calculate the Glicko (preferably Glicko 2) rating of a player by just using a pen, a paper and a calculator?

Of course it is possible! All the functions needed for the calculations are available on a scientific calculator, e.g. square root, log, value for pi, etc.

The Wikipedia page should get you started.
Mark Glickman's page on the system should take you further.

This pdf has detailed descriptions and equations for Glicko-2 - http://www.glicko.net/glicko/glicko2.pdf.

Javascript code for implemeting Glicko-2 is available here - https://www.npmjs.com/package/glicko2.


Whenever I haven't played for a while I go through a book with 200 mate in two exercises. Easy stuff, but quite a lot, just to get into gear again. Chesstempo will serve a similar function for you.

But that is just to shake off the rust and not blunder too much. To get back to the playing strength from four years ago or to become even stronger, you should rather train calculation instead of tactics. I.e. not just combinatorial vision but the systematic calculation of long lines. The Dvoretzky books have exercises for that, but those are pretty difficult.

The main point is that in my experience servers on which you solve timed problems aren't really suited to improve calculation. Even just picking random positions from these 10000 puzzles and calculating them like you would in a game is a better way.

You should also reacquaint yourself with your openings, by looking up your old repertoire lines and then play some internet blitz to get a feel for the variations again.

You are in the enviable position of living in Amsterdam so you don't really have to spend money on books yet. The Max Euwe Centrum has a library of chess books in many languages, entry is free and you'll find the newest books on every possible opening and avenue of chess improvement.


Longest number of moves that have been identical in two independently played games on record

There are Several reasons for identical games:

The fact that we databases and computers allows us to find the best move in known positions. (if both players knows the theory in the same level - it might lead to a known draw).

Hence some players might follow a known game between two great players, which might result with identical games.

The fact that there are known traps, might lead to to the same trap (when one player knows the theory and the other fall in the trap)

In this case, the game might end after the player fall in the trap.

In same cases, following a theory might lead to a lose as in the below story about Vishy Anand:

Vishy Anand loses in 6 moves after following a known game

[White "Zapata"]
[Black "Anand"]

[FEN ""]

1.e4 e5 2.Nf3 Nf6 3.Nxe5 d6 4.Nf3 Nxe4 5.Nc3 Bf5?? 6.Qe2

Anand resigns

  The story goes: reaching the position after white's 5th move,Anand
  recalled the publication of the game Miles-Christiansen,in the
  Informator(a highly respectable chess journal),which went 6.Nxe4,Bxe4
  etc....Impressed with the ease with which black had drawn in that
  game,Vishy decided to try it himself.But,after 6.Qe2,black just loses
  a piece.

  Now,how could both Miles and Christiansen have missed such an
  obvious move???? The answer is........they didn't!!That game had been
  agreed drawn in advance.Something the Informator had not revealed.At
  the board,Miles did see that Qe2 was winning,but remained the
  gentleman,and avoided playing it.It is said,that he did spend some
  seconds polishing the e2 square with his finger,untill Christiansen's
  face had the appropriate shade of red,whereupon Miles took on e4.

Two Identical games

Here you can find

Two identical games for the first 28 moves

A Lopukhin vs Alexander Semeniuk (1975)
Yakov Estrin vs Hans Berliner (1965)

48 Moves - Both Haugen (2523)-Fernandez (2437), 2010, and Bross (2587)-Efremov (2574), 2011, reached the same position after 48...Qd7+:

This is my source for the below Answer, in this link you can find more identical games.

[Event "Uxbridge Int Alekhine"]
[Site "Uxbridge ENG"]
[Date "2010.02.17"]
[Round "8"]
[White "Rudd, J."]
[Black "Gormally, D."]
[Result "1/2-1/2"]
[ECO "B90"]
[WhiteElo "2286"]
[BlackElo "2479"]
[PlyCount "18"]
[EventDate "2010.02.13"]
[EventType "tourn"]
[EventRounds "9"]
[EventCountry "ENG"]
[EventCategory "2"]
[Source "Mark Crowther"]
[SourceDate "2010.03.01"]

[FEN ""]

1. e4 c5 2. Nf3 d6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 a6 6. Be3 Ng4 7. Bc1 Nf6 8.
Be3 Ng4 9. Bc1 Nf6 1/2-1/2

Another Game:

[Event "ch-SUI"]
[Site "Lenzerheide SUI"]
[Date "2010.07.16"]
[Round "9"]
[White "Jenni, F."]
[Black "Kurmann, O."]
[Result "1/2-1/2"]
[ECO "B90"]
[WhiteElo "2542"]
[BlackElo "2449"]
[PlyCount "18"]
[EventDate "2010.07.08"]
[EventRounds "9"]
[EventCountry "SUI"]
[Source "Mark Crowther"]
[SourceDate "2010.07.19"]

[FEN ""]

1. e4 c5 2. Nf3 d6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 a6 6. Be3 Ng4 7. Bc1 Nf6 8.
Be3 Ng4 9. Bc1 Nf6 1/2-1/2

Another Game:

[Event "Moscow Dvorkovich Memorial"]
[Site "Moscow"]
[Date "2009.09.11"]
[Round "4"]
[White "Gansvind, Valeriya I"]
[Black "Pisakov, Ilia"]
[Result "1/2-1/2"]
[ECO "B90"]
[WhiteElo "2226"]
[BlackElo "2331"]
[PlyCount "18"]
[EventDate "2009.09.08"]
[EventType "tourn"]
[EventRounds "13"]
[EventCountry "RUS"]
[EventCategory "4"]
[Source "ChessBase"]
[SourceDate "2009.11.03"]

[FEN ""]

1. e4 c5 2. Nf3 d6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 a6 6. Be3 Ng4 7. Bc1 Nf6 8.
Be3 Ng4 9. Bc1 Nf6 1/2-1/2


Is there any chess software that tutors beginners?

The Chessmaster series.

IGN said that the series has always distinguished itself with first-rate chess teaching tools and this is the best selling chess franchise in the world. It virtually has no rival in chess teaching software, at least as far as my research goes. Chessmaster doesn't have the best chess engine though, so if you plan on playing professional chess you'll need a better engine after you reach master level.

I owned a copy of Chessmaster 10k and it featured, from what I can remember:

tutorials from Josh Waitzkin on the basics of chess, openings, endings, tactics, strategy, analysis of his own games
attacking chess by GM Larry Christiansen
chess puzzles by John Nunn
written analysis of 900 famous games
a searchable database of about 500k games


...... Stockfish isn't designed for solving a position like this. It's being written to play a good game of chess. Your position is not a position that SF should give an equal score.

The engine doesn't understand there's no mating possibility if White does nothing but moving the king. It gives a high score for Black because of the extra materials. Humans wouldn't even consider with any of the pawn capture, but SF has no idea.

Unfortunately, SF doesn't have the power to solve chess.