# Questions tagged [theory]

Theory commonly refers to the erudite study and the philosophy behind the moves in chess (like the opening or endgame theory), but this tag can also be used for questions about the theoretic study of the game itself.

406 questions
Filter by
Sorted by
Tagged with
1 vote
119 views

### Are all moves or types of moves (see details) in chess possible?

Inspired by this video The rarest move in chess, in which moves are categorized based on the format of their algebraic notation, so for example the rarest type of move (according to the author and ...
27 views

### What makes alternative winning conditions good or bad in chess variants?

For chess variants that keep all or most of chess movement rules but with different winning conditions (can be in addition to the normal winning condition or replacing it), what properties/...
1 vote
38 views

### Relationship between having a selfmate and having a checkmate?

Usually in selfmate problems white has material advantage to be able to force black to checkmate white, so white likely has a conventionally better position or has a forced checkmate. But not always, ...
57 views

### Up to which number of moves has the result of chess been calculated?

Chess hasn't been completely solved yet, even though it is completely deterministic. However, can't we "solve" it up to a certain number of moves (e.g., up to 50 moves)? Then, considering ...
61 views

### Incorrect upper bound on number of possible chess positions (10^41)?

I've written a script implementing a basic idea to count the number of chess positions. I've not even accounted for legality of the positions or difference in light and dark square bishops. Despite ...
• 535
1 vote
401 views

### DTM in a random N-piece position

Formulate how many plies are the DTMs if there are multiple checkmate variations (Depth to Mate ignoring 50-move rule) for a random N-piece chess position if any checkmate exists, (and also consider ...
1 vote
204 views

### Why hasn't any new endgame theory been developed from the endgame tablebases?

With all 7-man endgame tablebases completed years ago, and the 8-mean endgame tablebases in the works now, why have we not seen new strategies outlined for, say, how to win with rook and two knights ...
• 435
68 views

### What is this wide split in the Kmoch nimzo between stockfish's evaluation and master-level move choice?

In the Kmoch Nimzo Indian (sometimes called the f3 nimzo) [FEN ""] 1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. f3 d5 5. a3 Bxc3 6. bxc3 c5 (6... dxc4!? 7. e4) The move 6...c5 is the most popular ...
• 199
72 views

### Which Chess Notation is Most Commonly Used in Grandmaster Classic Games?

I'm interested in understanding the preferred method of notation used in classic games played by grandmasters. Specifically, I'd like to know which version of writing the moves of a game is more ...
143 views

### After 1.d4 d5 2.Nf3, what are the differences between 2...e6 and 2...Nf6?

Black plays 2...e6 8% of the time, 2...Nf6 77% of time. It seems that by playing 2...Nf6, Black keeps open the option of playing ...Bg4 and ...Bf5 (which would be the Slav if White plays c4 and Black ...
• 4,848
203 views

### What's the easiest way to hold this 4 vs 3 pawns on same side rook endgame?

After having been under tremendous pressure due to a mistake in the middle game and with only 30s on the clock, I was very relieved to find a way to liquidate into this endgame, which I knew was a ...
• 6,222
120 views

### Can previous and continuing research on N-piece tablebases be used toward human theory of chess?

This follows another questions here: What is the status for EIGHT piece endgame tablebases? My answer there was appropriately removed as being question in reaction to that question, well in light of ...
• 162
15k views

### Theory behind the Cow Opening

Recently IM Eric Rosen played the Cow Opening every game in Titled Tuesday, scoring 6.5/11 and increasing his rating. He streamed it and put it on YouTube. It is a Hippo style opening which can play ...
• 98.5k
1 vote
105 views

### Why is Nf6 a blunder here?

With Nf6, I'm trying to bring my Knight out. If the Bishop takes it, I can take the Bishop with by g7 pawn. Why is this a blunder?
• 179
187 views

### London system move order nuances Qb6 without Nc6

In the London system, playing early Nd2 is recommended to react against Qb6. For example if we take this move order [FEN ""] 1. d4 d5 2. Bf4 Nf6 3. e3 c5 4. c3 Nc6 5. Nd2 Qb6 6....
• 2,742
6k views

### Forced mate from move one - what is this train of thought called?

I have intuitively thought that one of the following must be true: White has a forced mate from move one. White doesn't have forced mate, but does have a forced draw from move one (and in turn, black ...
• 173
136 views

### London system plan against Qxb6 when white has time to go a3 and Rc1 getting out of pin

In the London system where white doesn't develop the b1 knight early the Qxb6 followed by a3 is considered a mistake due to the following sequence [FEN ""] 1. d4 d5 2. Bf4 Nf6 3. e3 c5 4. ...
• 2,742
794 views

### QGD is 3... Be7 better than 3...Nf6

3...Be7 a.k.a the Alatortsev Variation is a possible response as black for QGD players When I checked with the database 3...Nf6 is the most played move instead of 3...Be7. When black plays Nf6 they ...
• 2,742
1k views

### When did this chess game against ChatGPT diverge from theory?

I have recently been tinkering on and off with ways to make ChatGPT play chess. This has worked somewhat well, even with ChatGPT3.5, using a prompt crafted to make ChatGPT re-prompt itself at every ...
• 782
163 views

### Are all main lines and variations of chess openings necessarily SOUND?

Are all main lines and variations of chess openings necessarily SOUND?. I mean since we can't know all possible games, unique games, which are so large, about 10⁴⁰, how can I be sure that all "...
• 255
111 views

### Can you suggest book references on chess theory?

as stated in the title I am looking for structured textbooks on chess. I have followed chess.com lessons and I have a rough idea of tactics (forks, pins, skewers, sacrifices, etc) but I feel like I am ...
341 views

### How to Learn Chess Comprehensively

I'm a pretty new to playing chess - I understand the fundamentals and can implement some of the basic ideas like forks and pins, but have never properly learned how to play. I'm looking for a ...
• 51
62 views

I have many books that show openings, endplays, tactics, different puzzle to find best moves, databases with games, articles... All this stuff shows specific moves, which I have to find by myself. I ...
351 views

### Opening Theory in Hexagonal Chess?

Is there any opening theory in Glinski's hexagonal chess (rules here)? If so what are some standard openings?
• 98.5k
1 vote
105 views

### Is white winning in chess with the 1st and 8th ranks reversed?

Here is the position I am referring to: [FEN "RNBQKBNR/pppppppp/8/8/8/8/PPPPPPPP/rnbqkbnr w - - 0 1"] It seems that there are no forced checkmates for white, any f3-Qh4# plans are thwarted ...
• 535
391 views

### Chess960 - can Black profit by being allowed to choose a custom setup?

In Chess960, the White position is mirrored. In some positions, White enjoys a larger first-move advantage than in standard chess. Could we make Chess960 fairer by allowing Black to choose his setup (...
• 6,222
89 views

### Most advantageous starting position in chess [duplicate]

What is the most advantageous starting position in chess for White? All Chess960 positions are known to be roughly equal (the standard chess position being one of the fairest starting positions; in ...
• 6,222
1 vote
218 views

### How to study highly theoretical openings like the Najdorf, the Grünfeld, or the Ruy Lopez

So I'm probably not at the stage where I'm ready to do this yet, but I'm curious. I know that some openings (like the Najdorf, the Grünfeld, and the Ruy Lopez) are considered highly theoretical ...
• 139
10k views

### What do modern chess players understand about the game that previous generations did not?

In an interview, Garry Kasparow stated that each generation of chess players knows more about the game than the previous one. He applies this thought concretely to the question of who is better - him ...
• 687
518 views

### What is the idea behind the Nd7 Nb6 by black maneuver in the King's Indian Defence?

I have seen this idea often and want to know the idea behind it. White can create a doubled pawn weakness on b7 and b6 by doing Bxb6, but then would black have control over f4 and also c5? (unless ...
• 2,742
2k views

### What are some good "club-player" Sicilians?

My criteria for good "club-player" openings are: objectively good as little memorization is needed as possible forgetting theory / messing up move orders / playing mediocre moves won't kill ...
• 6,222
699 views

### Estimation of "God's Elo"

Assume a 32-piece tablebase would exist. It would be a Chess God. Surely there have been estimations of its ELO? According to the very related question, two problems arise: a) At any point the ...
• 16.5k
172 views

### Why not e3 instead of e4 in Grunfeld Russian system?

In the position below White continues with e4 after, say, Black castles. grunfeld-defense: [FEN ""] [StartPly "10"] 1. d4 Nf6 2. c4 g6 3. Nc3 d5 4. Nf3 Bg7 5. Qb3 dxc4 6.Qxc4 ...
3k views

### How to learn endgame theory

Related: How to improve on the early endgame? How exactly do I study or learn endgame theory? Is it just memorizing certain positions that are quite common and knowing how to attack and counter?
• 1,163
300 views

### Does chess intuition take over when you can't see all of the moves ahead? What does chess intuition look like?

This is a broad question about intuition and chess. I imagine that there is a limit to how far ahead even the best chess masters can see into the future, and how far they can stretch their memory. ...
• 31
292 views

### How do super-GMs, with the white pieces, avoid drawish positions?

I'm an amateur, so I don't have too much knowledge of contemporary opening theory, especially now that engine analysis allows frequent innovation. But I would like to ask the following: If two super-...
1k views

### d3 lines of Ruy Lopez vs. Italian

I haven't played the Ruy Lopez at all but I am curious about how it compares to the Italian. I've heard that one reason the Ruy is supposedly better is because White has an easier time playing d4 in ...
• 1,977
593 views

### Three Knights vs one Queen, which is better?

Suppose the end game contains three knights and king only for white, and one queen and king only for black. Which side is considered to be in a stronger position? Value-wise, the knights are worth 9 ...
• 149
715 views

### Is this theoretical novelty double-piece sacrifice actually sound?

Working my way through Hannes Langrock's book on the modern Morra Gambit (second edition), I came across an interesting sacrifice that he believes is at best worth a draw. Indeed that's also Stockfish'...
• 597
1 vote
582 views

### Sharp lines in the QGD, for black?

As a 1.e4 player who deeply enjoys sharp lines and studying/memorizing openings, I have always struggled with responding to 1.d4 since it leads to slow positional lines which usually have multiple ...
• 930
7k views

### Is there a mathematical theorem that you can use to win a chess endgame?

Have mathematicians created any theorem that determines the outcome of a endgame? If so, how could it be used to win a specific endgame?
1k views

### Why is this position in the 3.d4 d5 Petroff equal?

I'm trying to learn some theory about the Petroff and was reading about the 3.d4 d5 sideline. Eventually, the position below is reached. [FEN ""] 1.e4 e5 2.Nf3 Nf6 3.d4 d5 4.exd5 exd4 5.Qxd4 ...
• 477
1 vote
163 views

### Is it computationally feasible to find a board with proven outcome, reachable in 2 plies?

As is well known, neither the 0-ply game, the starting state, nor 1-ply games, all of white's first moves, have rigorously proven outcomes. Not even first moves for white considered very bad (1. g4) ...
1k views

### Before Qe6 in game 6 of the 2021 World Chess Championship, was it really a draw?

In game 6 of the World Championship 2021 between Magnus Carlsen and Ian Nepomniachtchi, before Qe6 the engine says +0.9 at around depth 30/99, but I heard supposedly it's a (theoretical) draw. I know ...
• 2,170
285 views

### "Strong ICCF players" What is your input into the game? [duplicate]

This question is directed to the experienced ICCF players. My question is basically what is the input that the human player has into the game. I was just wondering because with the use opening books, ...
• 2,158
3k views

### What are the advantages of keeping the identity of a second secret?

At the top levels of chess the identity of the coach/assistant is sometimes kept secret. What are the advantage(s) of this? I found: That mystery [second] turned out to be the intensely creative ...
• 2,107
358 views

### Could you recommend me game collection books of attacking players?

I have found a lack of aggression in my style and I want to study aggressive players' games to develop my style. Please recommend books that fulfill this purpose. I am an advanced player.
156 views

### How feasible is 7.Qa4+ in this Ponziani sideline?

Recently I played a game with a fairly standard Ponziani opening when something slightly interesting occurred. The game started as thus: [FEN ""] 1.e4 e5 2.Nf3 Nc6 3.c3 Nf6 4.d4 Nxe4 5.d5 ...
• 477
1 vote