# Question
Title: What's a good way to learn opening theory?
I'm a hobbyist chess player and usually play online. While I've seen thousands of great chess games and win a fair number of games online, the one thing that I have struggle with is studying openings. Simply put, there are just so many of them and each of them has so many variations. And to add to that, every out-of-book move my opponent makes throws me off and I don't know how to continue, so it turns out to be some hybrid/weird opening (or perhaps its a real opening with a name that I just don't know about)

I guess my question would be:

1. What's a good way to learn some of the common/easy openings? Is it just memorize or understanding the principles for instance, what that particular opening is looking to achieve?
2. How do I identify which of the variations to look at for a particular opening, there are often so many?
3. What's a good strategy to deal with my opponent suddenly going out of book or playing a novelty in an opening that I've memorized?

# Answer
> 17 votes
In reading your question, I can't help but think you aren't asking your real question, which I read as, "When I'm out of my book I get abused. How do I stop this from happening?"

I'm assuming that, like me, you're a USCF player rated under 1800. I offer the following advice:

1. Learn two openings with White and two with Black. Choose white openings begin with e4 or d4. Avoid long lines where your opponent may be more booked-up. At the amateur level, most openings and variations are playable. Your openings with the Black pieces should be sound but off the beaten path a little. Study games online, buy books, whatever. Hour for hour, books are cheaper than movies. Go for it.
2. Find an instructor who's rated 400 or more points above you. Ask this person to help you with your game, especially when you're out of your book. They'll help you with applying guiding principles. Chess principles are simple until it's time to apply them. Your instructor can help.
3. Don't memorize without understanding. It is critical to understand why book moves are standard.
4. Don't be afraid to lose. "I'm out of my book, I better play it safe!" is poison.

# Answer
> 10 votes
1. Write your opening down somewhere . Read it every day. Play it against real opponents / engine. Analyse your opening games, did you move the wrong piece? Try to figure out the plans of the opening. For example in `c5` sicilian, one plan might be playing `d5` if white played `f3`, because `f3` is really weak after the trade-off on `d5`.
2. Just play nearly every variation and take a look at the end position. If you like it, write it down, remember it and play it. If not, discard the variation.
3. You need to know the plans of the opening and not only the moves. If you know the plans, you can play without knowing the moves.

It might be hard to figure out the plans on yourself, but you might find some good games of chess in the internet, which are documented / commented from a good player.

# Answer
> 6 votes
Studying Opening Chess theory is definitively not about memorizing long lines of theory where you'll get lost if you opponent diverges... Also what to do next once you're out of your book?

The best way is....to practice!

In a nutshell:

* Study Few GMs or important games for that opening and/or system you would like to play: you'll get a general feeling of the opening/variation, you'll identify tactical and strategical ideas...no opening manuals at this point!
* Then Practice, Practice and Practice! (numerous blitz, 15 minutes games, even longer time control) the more the better!
* then only take a look at some opening manuals on this very specific line / system: you'll soon realized you have memorized and understood more than you =thought possible!
* Rinse and repeat!

If interested, I wrote detailed post on this very topic: http://improveyourchessornot.blogspot.ca/2013/05/how-to-study-opening.html

Hope it helps,

Cheers!

# Answer
> 5 votes
It's better to know a few good openings well, rather than a bunch of various ones. You might get thrown by some novel (to you) opening by learning a few basics, but unless you're a master who has time to learn many of them, your best defense against seemingly novel openings is good fundamentals. It will be less often that someone will be able to throw you if you focus on a few fundamental lines.

* Learn the theory behind the most common openings for white that stem from e4-e5, such as Ruy Lopez or Italian game.
* Learn one of the most solid responses to 1. e4, such as the Sicilian, or maybe the Caro-Kann.
* Learn the most classic responses for white to the Sicilian
* Learn the most common theory behind the most common lines after 1. d4 d5

# Answer
> 2 votes
I highly suggest finding one or two openings for each side,and then playing them against computers and people until they become second nature. I personally enjoy playing the Grand Prix, Fort Knox, Dunst openings; however, those are all just my personal preferences.

# Answer
> 2 votes
In my opinion a lot depends on your level.

For a *beginner* I would not recommend to learn an opening by heart. Instead focus on tactics and play openings based on general opening principles:

* occupy the center
* develop minor pieces
* castle
* don't blunder a piece to some tactics

A good indication for when you need to learn some opening theory is, if you regularly end up with slightly worse positions after the opening. (If you lose a piece or more in the opening, that would usually mean that you should improve your tactical skills instead).

# Answer
> 1 votes
Write the various ideas that you discover in the opening. For example, in the Taimanov Sicilian against the English Attack when White attacks the Knight with g5, Black should consider playing Nh5 and using the Knight to blockade the kingside. As you understand more and more ideas in the opening (and write them know), you'll begin to understand that it's not about memorizing moves but understanding how to respond to various plans that the opposing player can try. That's should be your mindset when learning an opening. Don't memorize - understand.

# Answer
> 1 votes
The best way, in my opinion, to learn opening theory is to study a chess database. Chessbase has a free one online, and so does chesstempo.

Look up games that match a particular position of your choosing. See what moves strong players play (also look at win percentages). Think about what moves you or an opponent would play in a particular position, and see how strong players respond. If there are no, or only a few games played in whatever line you are investigating, you can use a free engine, like Stockfish for example. Lastly, every time you play a game of chess, think about looking up in the database the opening that you played. And of course, the entire time, you must try to understand why the moves are being played. If you don't do this, it will be very difficult to remember lines.

---
Tags: opening, study
---


# Question
Title: If a pawn promotes to a checking piece while also revealing a check, it is a double check?
I'm writing a chess engine just for fun, and during the validation of movement generation, I found some positions in Perft Results that differ from what my engine is producing.

As an example, take the below position.

```
[FEN "r3k2r/p1ppqpb1/bn2pnp1/3PN3/1p2P3/2N2Q1p/PPPBBPPP/R3K2R w KQkq - 0 1"]

```

I found in the Chess programming wiki, the number of possible positions in depth 5 is 193690690, and my program matches this value.

However, regarding the number of possible double checks, my program found 8 more positions. The Perft Results from the Wiki indicate a total of 2637, while I found 2645.

I don't know what to think. Maybe the Perft Result from the Wiki does not consider positions where a pawn promotes with check whilst revealing a check, aka a discovered check. But there are only 6 moves where a pawn promotion results in a double check (3 positions, where the pawn may promote to queen or rook). Are the positions from Wiki wrong?

If someone wants to look at the positions, they can be found here on Google Drive.

# Answer
Yes, a double check is when two pieces give check at the same time. It doesn't matter how you got to that position. As to whether there's an error on that wiki, it's probably best to try to ask its author. Maybe they can provide the full list of positions for you to compare.

I can think of two ways of giving double check while promoting. One is where you have say the black king in front of the white pawn, and a white queen or rook behind the pawn, and the pawn promotes with a capture, ending up as a new white queen or rook next to the black king. The other is where say the black king is on the seventh rank, white has a rook or queen on the other side of the pawn, and White promotes to a knight, queen or bishop giving check.
> 6 votes

# Answer
Yes, the case you mentioned would also qualify as a double check.

But it also depends on what your definitions are. If the Perft result does consider that to not be a double check, it doesn't mean you have to abide by it.
> 3 votes

---
Tags: engines, programming, pawn-promotion, performance, double-check
---


# Question
Title: Whose games should I collect for Scotch Opening?
I have been adopting the Scotch opening recently with some moderate success. I would like to know whose games should I look at to have a good understanding. I see that Nakamura and Kasparov deploy Scotch reasonably often. Apart from him, I was surprised to see that Tal used Scotch in only 3 games and Fischer never. I was under the impression that Scotch gives rise to dynamic active position and hence my surprise.

# Answer
I religiously play scotch in e4/e5 games. Sergei Rublevsky is the star I follow.
> 4 votes

# Answer
Magnus Carlsen has some games as White you might look for. GM Parimarjan Negi authored a DVD on the Scotch and has himself played it on many occasions.

Fischer loved the Ruy Lopez so didn't have much need for the Scotch, and in general fashion has favored the Ruy Lopez. Then Kasparov resurrected the Scotch (he even had an affair with the Evan's Gambit) and it saw new light.
> 2 votes

# Answer
I generally prefer GM Negi Parimarjan, who is the master of the Scotch Opening and, as mentioned above, he has created a DVD series.

He has played Scotch lots of times.
> 2 votes

# Answer
Kasparov has some good examples. Se http://www.chessgames.com/perl/chesscollection?cid=1017006
> 1 votes

# Answer
There is a new book on the Scotch by Alexander Khalifman (who is sort of an ex world champion).
> 1 votes

---
Tags: opening, scotch-game
---


# Question
Title: Why is 6. Nge2 better, and 7. d5 a necessary push in this game?
I have two questions about a recent game that I played on Lichess.

---

Question 1:

Why is it necessary for White to push d5 now in the game, in this position, and why is Be3 a blunder?

I did play d5 later in the game on move 10, but I cannot understand why, if no disruptive move such as c5 or a well timed e5 (although probably impossible here) is made, I should push d5 at all.

---

Question 2:

Why is e2 the best position for the King's knight, and not f3 in the next diagram (on move 6 by White)?

There does not appear to be any annoying pin of the knight on f3 by a bishop on g4. Plus, I do not think it is disadvantageous to have doubled pawns on my position(if needed I could play Bd2 when Black plays Bb4). Lastly, and more importantly, the knight on f3 can jump to e5 if possible.

# Answer
1) After 7.Be3 Bxc3 8.bxc3, Black could have won the e4-pawn with ...Nxe4. The purpose behind 7.d5 would have been to block the b7-bishop, preventing Black from winning the pawn.

2) I don't think 6.Nf3 is that much worse than 6.Nge2. Lichess still says White's better by 0.7. But the advantage of Nge2 is that it protects the c3-knight and after 6...Bb4 you can play 7.0-0 with no issues. Since now 7...Bxc3 is answered with 8.Nxc3, and you still have a knight on c3 (preventing Black from winning the e4-pawn).
> 6 votes

# Answer
Nf3 is not horrible (it actually transposes into a position that Kasparov once had as White, and won.) I think the reason the engine doesn't like it is that after your proposed Nf3 Bb4 Bd2, Black may play Bxc3. If that knight is on f3, than after you retake with Bxc3 or bxc3, Black can safely take on e4. If instead the knight was on d2, then you just play Nxc3 and e4 is defended. (See the blunder by Black a little later where he doesn't take on e4.) You do have other options after Nf3 to not lose the pawn, but your pawns may get doubled.
> 6 votes

---
Tags: analysis, positional-play
---


# Question
Title: Is it possible to play multiple games with Stockfish simultaneously?
I am asking this because Stockfish was accepting different FEN strings through the terminal inbetween a game, of which it is giving best moves. I have compiled Stockfish in the Ubuntu 19.04 terminal.

# Answer
> 1 votes
In Chessbase you can have Stockfish analyzing/playing in multiple boards. It's definitely possible to do this, but it slows Stockfish down since it's being overworked. So it'll take longer to search ahead in each game.

---
Tags: stockfish
---


# Question
Title: When is it possible to carry out the "En Passant" manoeuvre?
This manoeuvre is a form of pawn capturing technique. When a player’s pawn jumps two spaces on a first move, that piece can then be taken from the side as the opposing pawn moves into the moving pawn’s “lane” behind it, capturing it.

My question is, are there any other conditions where this move cannot be carried out such as to prevent check or checkmate or to carry out a check or checkmate?

Also, is this move allowed in tournaments and the like?

# Answer
You can't take a pawn en passant if that pawn just made a discovered check to your King:

```
8/8/7k/8/2p5/8/3P4/2B1K3 w - - 0 1

1. d4+

```

After 1. d4+ Black is in check (their king is attacked by the White bishop on c1) so he has to move his King. 1...cxd3 is not allowed.

Also, it can't be carried out if your pawn is pinned to your king:

```
6k1/8/8/8/2p5/8/B2P4/4K3 w - - 0 1

1. d4

```

The Black pawn on c4 is pinned by the White Bishop on a2. If that Pawn moves, the White Bishop would be able to take the Black King. So after 1. d4 the move 1...cxd3 is not allowed.

I can't think of any other condition where this move can not be carried out.

And yes, en passant is allowed in tournaments of course. But when you take a pawn en passant, do not say "en passant" aloud (some low rated players do that, they also say "check" aloud when they put the other player's king in check) since it can break your opponent's concentration (and the concentration of the other players near you in the playing hall).

Wikipedia has a good article on the en passant rule.
> 9 votes

# Answer
An en passant capture is just a capture. There are no special rules other than its definition, as described in the question. Put another way, you capture the pawn as if it had only moved forward one space.

Of course, the capture isn't exempt from the rest of the rules. For example, you can't make a move that leaves your king in check, so you can't make an en passant capture that leaves your king in check. But there's nothing special about en passant captures here; all the usual rules apply.

And, yes, the rule applies in tournaments. Don't think of en passant captures as something special; despite the seeming quirkiness, they're no more special than castling, which also has its own quirky rules.
> 9 votes

# Answer
The en passant is subject to all the usual rules of chess. So you cannot use it if it would be illegal to move your pawn (for example if your king is in check and the move would not get you out of check, or if the moving pawn is pinned to the king, etc.). It is part of the official rules of chess, and is absolutely allowed in tournaments.

There is one important additional rule about en passant: **it can only be used on the move following the move of the captured pawn**. (Rule 3.7d) You cannot wait a few moves and then use the en passant capture.
> 5 votes

# Answer
The best way to think of en passant is that it's a normal move in all regards, except that the opportunity to play it expires on that move.

The move can be carried out so long as it doesn't break any rules, just like any other move. So it can be used to block a check, give a check, give a checkmate, etc. But let's say your pawn is pinned to your king. If performing an en passant capture with it leaves your king exposed to an enemy attack, this is illegal and thus not allowed (istg).
> 3 votes

---
Tags: rules, tournament, en-passant
---


# Question
Title: Tips for debugging and progressing a chess engine's implementation
As I mentioned in previous questions I'm currently following this tutorial for building my chess engine.

The code was written in C#, but mine is in C++ and I'm in the phase of finalizing the board / piece / moves / valid moves representations without testing the logic just making sure the syntax is ok.

So I'm confused as to what should I do now, just continue writing without testing or there is a good way to test an incomplete chess engine?

Here you can take look at what I have done so far and your comments / recommendations are appreciated

# Answer
> 3 votes
I glanced at your code:

* You should test your code with **perft**. Google it if you're not sure what it is.
* Please make sure your code works before coding the engine search. If you unable to generate moves properly, nothing in your search will work.
* Consider to use an array rather than a switch statement for piece values.
* Consider to code your squares as an integer, not as a C++ class
* Consider to collapse your WHITE and BLACK implementation together. C++ template would do that for you. Please take a look at Stockfish codebase if you're unsure.
* I don't see you're making **en passant** in the code. Are you sure you have that covered?

# Answer
> 1 votes
Is there a good way to test an incomplete chess engine? Yes, but nothing of what I'm going to say is chess-specific but really just good software development practice. Write unit tests. This means test each "unit" of your program in isolation. The most common unit is a function. For example, let's say your program has a function to check whether a position is a checkmate. Set up a bunch of positions which you already know whether they are checkmate or not, call your function with each position, and verify that it returns the expected result. Keep those tests around and run them automatically as part of your development cycle. That way you'll notice immediately if you broke something by accident.

You can even write the test before actually writing the function that you want to test. That is called test-driven development.

---
Tags: engines, software, programming
---


# Question
Title: Can a pawn that performed an en passant capture promote at all?
So let's say I capture en passant with a pawn. Using the same pawn, I get to the 8th rank. Can I promote that pawn into anything else? I've heard of this restriction in various ways. Some say it can become a rook at best, and some say it just stays as a pawn, but it moves backwards.

Please let me know if this is a classic case of "I'm losing better make some stuff," or an actual rule.

# Answer
> 23 votes
From FIDE rules (3.7 e):

> When a pawn reaches the rank furthest from its starting position it must be exchanged as part of the same move on the same square for a new queen, rook, bishop or knight of the same colour. The player’s choice is not restricted to pieces that have been captured previously. This exchange of a pawn for another piece is called ‘promotion’ and the effect of the new piece is immediate.

There is no restrictions whatsoever about capturing en passant.

# Answer
> 8 votes
For as long as I can remember, there has never been a rule like that in any official matter. The pawn captures en passant and lately it can promote like any other pawn.

# Answer
> 6 votes
The fact that a pawn has made an en passant capture does not alter or limit its capabilities at all, including its ability to promote to a queen or other piece when it reaches the eighth rank.

# Answer
> -2 votes
Nothing changes whatsoever to the pawn. It can still promote to a queen, rook, bishop, or knight.

---
Tags: pawns, pawn-promotion, en-passant
---


# Question
Title: Only being able to move and not capture while in check
I was playing chess with my Dad, and he was shocked when I made a capture while check. He said that when he learned to play, that, when you are in check, you cannot capture with the king or any other piece to get out of check. This means that all you can do is move out of check. Is there a special rule or game type where this is true? We live in Hungary, so maybe they play different here.

# Answer
> 6 votes
Below is for regular chess. I don't know about any chess variant which would have a rule like you describe.

If you are in check you have to deal with it somehow, i.e. after your move you should not be in check anymore. If there is no move which achieves this, it is check-mate.

There are at most three different ways to get out of check:

1. move the king out of check
2. capture the piece which attacks your king
3. put a piece in-between the piece which attacks your king and your king (this can only work if a bishop, rook or queen attacks your king)

A simple example:

White is in check by the rook on h7. There are three possible moves for white: Kg1 (see "1"), Bxh7 ("2"), Nh3 (see "3").

As a side note, you cannot castle out of check.

# Answer
> 1 votes
If you are playing chess, you are supposed to play according the FIDE Laws of Chess Art. 1 to 5. But those rules are not known to everyone playing „chess“ in private. The official rules allow every move or capture to get out of chess (except castling, of course). Private rules might differ, but those are not official, and one could discuss if the game described by those private rules is still chess.

---
Tags: rules, check, kings, captures
---


title: How to prepare for a rapid tournament

text:
# Question
Title: How to prepare for a rapid tournament
How can I prepare for a rapid chess tournament (not chess sites tournament!)? For example, in one and half months, I am going to play a 15+5 tournament. I tried to find some rapid strategy or some advice on opening or middlegame whether I should play positional or tactical or attacking. However, I couldn't find anything. Could you give me some advice or strategy for 15+5 time control?

# Answer
The best thing to do is play some games with that specific time control so you can get used to the pace.

Whether to play positional or tactical is a decision around your skills and what you know about your opponents play. Though it is considered more difficult to defend than attack and that can lead your opponent to use more time. It is also true that finding a plan is time consuming; so I would just play toward your skills. Certainly you should study a lot of tactics so you can calculate quickly.

In general, you don't want to fall behind on the clock. But you shouldn't panic if you do. And don't play on your opponents time pressure. 5 second increment is a lot. You should get comfortable defending "drawn" endgames where you can make a move within 5 seconds.

Semi-dubious openings like the Smith-Morra Gambit are common in quick tournaments. Prepare your openings so your opponents don't get to have any such fun!
> 3 votes

# Answer
There is no special rapid strategy for rapid. You should play the game you play in standard time. If rapid is new to you, you should play some games with the shorter time to get used to the faster moves.

But no rule without exception: If your opponent is stronger than you, you might try to make things more complicated to give him a chance to blunder. You might blunder, too, but that you would do with any move rate. The faster the game, the sharper the lines you can choose. (According to Simon Webb, Chess for Tigers)

Exception to the exception: If you play with time increment, that will reduce the chance of the stronger opponent to blunder. The higher the increment, the more normal lines you should choose.
> 1 votes

---
Tags: tournament, preparation
---


title: Pushing the e-pawn

text:
# Question
Title: Pushing the e-pawn
I am having trouble understanding why the move e5 which I played in the position below is not correct according to Stockfish (6th move for White)

I am not doing this move by winning a tempo, but I consider that this push would constrain Black particularly since d6 is no longer possible. and f6 would be quite weakening.

Another move I considered during the game (exd4 followed by d4) does not appear to be correct either. This way. I would prevent Black from further pushing their central pawns.

Could someone enlighten me in the pawn theory relevant to the diagram of the game?

# Answer
I disagree that it is primarily about development.

This is a very common theme, and it comes down to the fact that e5 is not easily defended by a pawn (aka "artificially isolated"). Bg4 soon will trade one of the e5-pawn's defenders, and it will need constant watching. It is not a big deal that you will be trading the Bc8 on f3 since white already traded on c6 so you are not giving up the B-pair, and after e6, the c6-d5-e6 complex keeps a nice hold on the light squares.

Black can attack the e5-pawn with Qc7, and Ne7-g6 as one plan. If White defends with the obvious Re1 and Bf4 (and later Bg3 after Ng6), then Rb8; b3 will leave White's dark squares very weak.

It is also important to note that defending e5 with d4 is also never good after cxd4; any c5 and another pc5 appears and a nice center for Black.
> 15 votes

# Answer
e5 does nothing for you and helps your opponent. Why?

First, it does nothing for your development. Much better would be d3 which releases the c1 bishop and protects the e pawn. If your opponent plays de then you retake de and he is left with doubled isolated pawns on the c file and an isolated pawn on the a file. If he doesn't then exchange queens he also has an open position with his king still in the center and is behind in development.

Second, e5 releases the tension in the center and takes all the pressure off your opponent. His development becomes easy. He will play Bg4, exchange the light-squared bishop for your knight, block up the position with e6 and calmly complete his development.
> 13 votes

---
Tags: strategy, theory, positional-play, pawns
---


title: How does Allie's search algorithm work?

text:
# Question
Title: How does Allie's search algorithm work?
Allie is a strong engine that's looking competitive with the top ones (Leela Chess Zero and Stockfish). It's supposedly based off AlphaZero, but works differently. As far as I understand it, the most important difference is the search algorithm. The author said in a March 2019 interview that:

> AT: To begin the tournament, Allie will perform MCTS based search with absolute fpu where new nodes start off with win pct of -1. The search is modeled after Deepminds paper’s. As I said above, **I’m hoping to switch to AlphaBeta for the long term direction of the project**. I’ve experimented with many, many ways of doing this with the networks generated by the Lc0 project and I think I’ve hit upon a way to achieve the depths required to maintain ELO level with MCTS based search, but it is not ready yet. In the future, I imagine we’ll see a lot of experimentation with different variations of search (mcts, ab) + eval (handwritten, NN) in computer chess engines. Hoping to be a part of that and to contribute to the shared pool of knowledge.

(Emphasis mine.) As of time of writing the Allie Github page says:

> Well, I was inspired during the original CCC to see if you could pair traditional Minimax/AlphaBeta search with an NN. This is still her main purpose and the focus going forward. However, the initial versions were using a similar pure MCTS algorithm as Lc0 and AlphaZero. **The current versions of Allie use a modified hybrid search of Minimax and Monte Carlo.**

I don't understand what "modified hybrid search of Minimax and Monte Carlo" means. Can someone explain? I know what each of these terms mean, but I don't understand the combination.

# Answer
Allie's search is a combination of MCTS and Minimax. The MCTS is very much like you would find in AlphaZero or LC0 as it was taken from the same papers. In addition to MCTS, Allie also does a minimax based backup of the tree whenever a new MCTS batch is evaluated by the NN. This minimax backup is then used to modify the Q values of the nodes in the tree that were either 'min' or 'max'. This modification is a further averaging of the MCTS based backups.

So:

* Allie uses MCTS for playouts and for back prop in much the same way as A0 and Lc0
* Allie also does a minimax-based back prop to supplement that mcts based back prop

I've also tried many, many, many, different ways of adding newer AB/Minimax to the algorithm, but so far nothing that has successfully gained elo over the above. Finally, I'll note that in all of my testing of Allie (pure MCTS) vs Allie (MCTS+Minimax) the latter has scored significantly higher so I am confident that it does improve elo at least in self play.

UPDATE:

Since I wrote this, the Allie minimax backup has grown more complicated. Now, in positions where the best candidate move is a terminal node Allie does a pure minimax based backup with no mcts averaging. If the best is *proven* best among all of its siblings, then the parent is also made terminal and assigned the inverse score of the best child. If the best is *not* proven, then it still does pure minimax backup, but the parent continues to be expanded and if a sibling becomes best it switches back to the combination of minimax+mcts backup. Finally, this is all kept track of for transpositions too.
> 7 votes

# Answer
“Minimax” means pick the move which minimises the value of the opponent’s best possible response. If the search space was small this can be applied recursively to essentially solve the game. However chess is too big, so one can’t search the whole space. The program is picking a bunch of different directions randomly (aka Monte Carlo) and finding the minimax over all of these. There is some secret sauce the designer is glossing over here, hence “modified hybrid”.
> -1 votes

---
Tags: engines, chess-algorithms
---


# Question
Title: Rejected game variant for adding a new chess piece
Some time ago İ had a book on chess, that proposed new chess variant invented by some guy, in which a new chess piece was added. so instead the usual 8 by 8 board would get replaced by a bigger 9 by 9 board in which a new piece could be added. This piece would be like the queen but it would be able to jump like knight making it a lot more powerful than the queen.

So my question is, what did you call this new piece that was proposed and who made it at what year? Any info on the subject is appreciated.

# Answer
> 9 votes
I was unable to find a variant with a 9x9 board that included this piece, but that doesn't mean such a variant doesn't exist.

Perhaps you slightly misremembered the powers of the piece. Modern Chess was invented in 1968 by Gabriel Vicente Maura, according to Wikipedia. It has a 9x9 board and features a piece called the "prime minister" which combines the powers of the bishop and knight. Unlike any piece in normal chess, it is capable of delivering checkmate without the help of another piece, if the opponent's king is in the corner.

It's also possible you may be thinking of Chancellor Chess. This was invented by Benjamin R. Foster in 1887, according to Wikipedia. It has a 9x9 board and features a piece called the "chancellor", which combines the powers of a rook and knight.

If you're sure that the piece was actually a queen and knight combined (and not a bishop and knight or rook and knight), then Wikipedia says this is called the "amazon", and that it has also been called "angel, ayanu, commander, crown prince, elephant, empress, general, giraffe, grand chancellor, maharajah, rettah, royal guard, superqueen, tetra queen, and wyvern".

# Answer
> 2 votes
I had the privilege of meeting Gabriel Vicente Maura in Puerto Rico when i was a teenager in the 80s. He brought to life in the 70s the World Federation of Modern Chess (Femdam) with the new piece called the Prime Minister which moves like a Knight and a Bishop on a 9x9 Chessboard..

---
Tags: chess-variants, minor-variations
---


# Question
Title: Speed of minimax with alpha beta pruning in chess engines
Can a minimax function with just alpha beta pruning really evaluate 1.8 billion chess positions (3 ply = 356) in just a second?

My chess engine, which uses minimax with only alpha beta pruning, takes 30 seconds to search 2 ply deep, evaluate the leaves, and determine the best move.

# Answer
There're some problems with your question:

* Alpha-beta pruning doesn't make you search faster, it makes you search *further*. For illustration (these numbers are not accurate) if your computer is searching at 1 million nodes (here a "node" is a position) per second, without alpha-beta pruning you might only make it 5 ply deep. With it, you might reach 10 ply.
* Obviously, how fast you search is going to depend on hardware. With sufficiently powerful hardware you can search 1.8 billion nodes per second. For example right now, Fishtesting is running with this hardware: 650 machines 5048 cores 1.21M nps (6127.86M total nps) 8825 games/minute. That's 6.1 billion nodes per second.
* However note that Fishtesting is running with 5048 cores. A typical desktop computer might have 4 cores, so this is fantastically powerful hardware. If you're getting 1.8 billion nodes per second, and you have reasonably normal hardware, your eval function is probably very simple compared to the top engines.
> 2 votes

---
Tags: engines, minimax
---


title: How to study endgames?

text:
# Question
Title: How to study endgames?
There are lot of recommendations on what endgame books you should read and study. But reading is just passive learning, and not so efficient.

If the book doesn't contain exercises, what is the best method for active learning and doing exercises?

One idea I have is to play the positions against an engine. Are there better suggestions?

# Answer
Personally, I love a number of great books, and there is still no substitute. You can then plug positions into a computer to test yourself.

I still love Fine's "Basic Chess Endings". Despite the errors, many corrected later in the Pal Benko edition, it gives a great sense of WHAT you are trying to accomplish in any type endgame. Simply by reading over all the examples, and the sub-examples, you will absorb a lot. Each sub-example, while meant to show an exception, or other deviation, is also reinforcement of the main idea.

For example as to my comment about "WHAT" you are trying to accomplish, take a minor piece endgame where you are up a pawn. The basic plan is to create a passer, and if your opponent blocks with the K, you run with your king to attack and take his other pawns. It he just tries to block it with the piece, you run over and force him to give up the piece for the pawn.

I studied this book when I was rated just 1036, and much of what I learned has stuck with me through being a Master almost 40 years later. No less than World Champion, Mikhail Botvinnik, considered it the best book on the endgame (although many greats ones have come along since). Fine's words are chess gold.

Next, I really like "100 Endgames You Must Know: Vital Lessons for Every Chess Player" by GM Jesus de la Villa. Not many books get a fourth edition, which is a testament to this book's appeal. In addition, he recently added "The 100 Endgames You Must Know Workbook: Practical Endgame Exercises for Every Chess Player", which lets you apply the 100 endgames from the first book in practical game exercises.

Lastly, if you really get strong, I still consider "Dvoretsky's Endgame Manual" THE single most instructive book ever written. That said, it is not for novices, and expects a lot of prior endgame knowledge. Similar to de la Villa's recent workbook, Dvoretsky also wrote "Tragicomedy in the Endgame: Instructive Mistakes of the Masters", which shows practical games involving information from DEM.

No matter what you do though, endgame study requires time and effort; however, unlike opening study, this study will stick with you for a lifetime.
> 9 votes

# Answer
I've practiced some endgames against the computer, and I think it has been useful but there are some caveats. It may depend on the engine (and the endgame), but I've found that sometimes when practicing a won position or defending a drawn position, the engine does not play "realistically", making the endgame unnecessarily easy to win or draw.

Let's use KP vs K endgames as a simple example. Let's say you have a won position. A stubborn human defender would try to block the pawn til the end, hoping maybe you'll slip and allow a draw. The engine may decide instead "I'm lost, but if I run away with my king now, it will be mate in 12 instead of mate in 10!", so the king runs away and makes the promotion trivial.

Similarly, if you are defending a drawn position, a stubborn human would try to keep the pawn and advance it until stalemate is reached. The engine concludes there's no difference, so I've seen it give away the pawn, leading to an immediate draw.

I've also practiced endgames with a coach, and it's much better, because the coach knows how to make tricky moves which give you the opportunity to make a mistake, instead of just trying to maximize the distance to mate.
> 5 votes

# Answer
Actually in a case of endgames you can split learning in two parts:

* Theory
* Practice

You have to start with theory - read books - those will explain ideas and principles. Then You can move on (can do it somewhat in parallel) to practice. There are lot of internet sites, PC and mobile apps for that - I will not advertise any specific - that would be unfair. You can even just set-up position and play Vs your engine until you succeed getting desired result(win/draw). Also - learning is never easy - if you want to achieve high level You will have to work hard, spending many hours on this!
> 4 votes

# Answer
> Are there better suggestions?

I find videos to be more effective than books and ideally the videos, as well as giving instruction, should also have problems related to the matter as you suggest.

My personal preference, which I find very effective, is the two DVDs on endgames produced by the Ginger GM, Simon Williams. The material is presented by English GM Nick Pert and covers everything you are likely to need from complete beginner (K+Q v K) through to GM level (K+R v K+B, K+h+f pawns v K, K+R+a,f,g,h v K+R+f,g,h, K+Q v K+R). You can find more details here.
> 2 votes

# Answer
I don't know about 'better', but solving chess endgame studies can be an alternative way.

Best introduction to that field is John Roycroft's book The Chess Endgame Study.

As for use of computer ... I'm in two minds. Yes, it makes it possible to get a slightly higher degree of realism, including the possibility of blunders (if your program allows you to set up that), but I think you also have to learn to see the position from the opponent's view ... and use of computer may not help very much with that.
> 1 votes

---
Tags: endgame
---


# Question
Title: Do chess AIs still use old-style opening books?
(See also this related question and this related off-site discussion.)

Do state-of-the-art chess AIs still **normally** start games in human-compiled opening books of master games?

Years ago, as far as I know, state-of-the-art chess AIs started games in opening books. That is, years ago, to choose their first few moves, rather than calculating, chess AIs instead consulted databases of master games.

Do chess AIs still do that?

If you wish to know why I ask, more than 20 years ago, I owned a dedicated chess computer like one of these. The computer would instantly play each of its first several moves, apparently without thinking. The computer would slow down and start thinking only after

* it had exhausted the book or
* its human opponent had made a poor move, deviating from the book.

Nowadays, however, playing on Lichess, where the Stockfish AI is available for *post mortem,* I notice no obvious sign that Stockfish were consulting anything other than its own analyses.

(One suspects that various interesting things could be written on the topic. My knowledge of chess AIs is limited. I may or may not have posed the question optimally. Therefore, feel free to interpret the question broadly at your discretion.)

# Answer
Chess engines are, of course, able to analyse opening positions and come up with reasonable moves, but opening books still come with some advantages:

* Moving instantly in the opening saves a lot of time, which can be spent on more complex moves later on in the game.
* Some more subtle theoretical moves in the opening may be missed without an opening book.

In engine vs engine testing, the overwhelming majority of games are conducted starting from an opening position, but the engines themselves are not allowed their own books.

When playing a human, many chess applications use books, but delay their move anyway to give the impression that the program is thinking. This has the advantage of allowing said application to offer a greater variety of openings, whereas relying on the engine's analysis would lead to repetitive games.

In analysis, it is common for to only start from the first move made out of book, because it is likely that moves made in-book are reasonable.

Lichess is somewhat unique in that it uses the engine to analyse every move rather than using a book for the first moves. The analyses of many opening positions are stored in the cloud to avoid duplicating work in the opening (you may see, for example, "Depth 39 \[CLOUD\]").
> 7 votes

# Answer
You're asking whether AIs still "normally" start games with opening books, and I find it hard to decide what "normally" should be. All engines can be configured to use an opening book.

For analysis purposes like in Lichess, there is obviously no opening book configured as that would mean it wouldn't analyze. Having the engine analyze the position and show an evaluation and a line is what the user wants, not just "5...d6" from an opening book without further information.

In human vs engine play, opening books mostly serve to randomize the openings the engine plays, so there they have a use. But deep opening books that contain huge amounts of lines are not that useful.

In engine vs engine tournament play, the trend is to do without opening books at all because otherwise it's more a battle of the books than a battle of the engines.

So what you get are groups of opening book enthousiasts who play *lots* of engine vs engine games and constantly try to tweak their books to beat the other engines, that are often the exact same engine but with a book made by someone else. This sort of thing is also useful for correspondence chess -- when a move is known to be a draw from thousands of engines games, it is not that promising for white to play it in correspondence where black can also use an engine.

As for "chess AIs instead consulted databases of master games", that isn't true. They consult an *opening book*; basically a long list of "in this position, play move X 60% of the time and move Y 40% of the time." Whoever made that opening book probably used a database of games, but the opening book isn't such a database by itself.
> 4 votes

# Answer
There're several closely-related interpretations of your question that can change the answer.

> Do chess AIs still use old-style opening books?

As I understand it, all chess engines these days can be configured to use an opening book, or to not use an opening book. So the answer is "if you want them to".

If you want them the engine to use an opening book, then you'll have to supply one. An example is the Cerebellum opening book. You can also, e.g., force the engine to play the Evans Gambit. Some commercial engines will also come with their own opening books.

If you don't want them to use an opening book, then you can disable the book. In this case the engine starts thinking from the first move.

> Do state-of-the-art chess AIs still normally start games in human-compiled opening books of master games?

As mentioned, this is a closely-related question that can nonetheless lead to completely different answers because different people use engines differently. For someone who's playing against the engine "for fun", the answer is probably yes, because otherwise the engine only plays a few openings. In engine vs. engine competition, both options happen. The "official" World Computer Chess Championship allows the use of opening books, while the unofficial Top Chess Engine Championship does not. There're advantages to both approaches, the details of which should probably be its own question.

The latter part of this - "human-compiled opening books of master games" - is also debatable. There've been attempts to create engine-compiled opening books, not necessarily of master games, but also including engine vs. engine matches.

Ultimately, engines are programs, and you can configure their settings to do whatever you want.
> 2 votes

---
Tags: opening, engines
---


title: How is this situation not a checkmate?

text:
# Question
Title: How is this situation not a checkmate?
According to the chess app I am using, this is not a checkmate against black:

```
[FEN "1rk4r/1p6/3p3q/Q1pPbRnP/p1P3B1/P6P/1P4R1/7K w - - 0 1"]

1. Rf7+

```

How is it not? I think the black king is checkmated by the queen and the white-squared bishop.

# Answer
> 45 votes
It is not checkmate because Black can interpose a piece to block the check from the bishop: move knight or queen to e6.

It's still only a miniscule delay for the inevitable.

```
[FEN "1rk4r/1p6/3p3q/Q1pPbRnP/p1P3B1/P6P/1P4R1/7K w - - 0 1"]

1.Rf7+ Ne6
(1...Qe6 2.Qc7#)
2.Qc7# 1-0

```

---
Tags: checkmate
---


# Question
Title: What is the most efficient way to calculate attack squares in a chess engine?
I have made a chess engine, and it seems from cProfile that my most expensive function is the one that calculates attack squares for both players. Here is the cProfile results for a perft function I wrote that goes 4 ply deep: https://i.stack.imgur.com/TADwV.jpg

The reason why my calculate attack squares function is so expensive is because every time a move is made in perft, the position is a new one, and attack squares for both players have to be recalculated. My question is this: Is there a more efficient way to be calculating attack squares for both players? Is there a way I can avoid having to recalculate attack squares for all 32 pieces every time a move is made in perft? Thank you.

https://repl.it/@kasparov/ImportantNotedCoderesource My code for anyone who's curious

# Answer
It may help to keep a list of each piece and the squares it attacks for the position.

Then when a move occurs, you can reduce the work calculating for the pieces that don't move. Non-moving kings, knights, and pawns will attack the same squares as before. Non-moving queens, bishops, and rooks only need to be recalculated if a piece moved to or away from a square they attacked.

Then you can update the attack squares of the pieces that actually moved.
> 2 votes

---
Tags: engines, performance
---


title: Caro-Kann c5-c4 push

text:
# Question
Title: Caro-Kann c5-c4 push
I am having trouble understanding why the push c4 here is incorrect for Black.

After 9. Qc2 b5 10. a4 a6 11. axb5 axb5 12. Rxa8 can be recaptured with the Queen and the pawn chain is stable.

What is wrong then with this push?

# Answer
> 6 votes
First, although it is hard to disagree with the computer there, it is interesting that 8...c4 scores quite well for black in the Mega 2019 database (only a 43.8% for white).

The first obvious thing that comes to mind is that anytime you change the base of attack on the pawn chain like that it does two related things (right now the base of attack is at d4 and black can attack it with c5...after c4 the new base is c3, and black will need to attack it with b5-b4): Typically when you push, it often makes the later break with b5-b4 stronger, but of course it does not come without a price...it is much slower so you may never get to play that break, or it might be ineffectual by then, especially on the q-side since with similar advances on the k-side threats to the king cannot be ignored. A very common example of this is in the King's Indian Classical Variation, when black plays f5-f4. It is slower, but there are countless examples showing just how dangerous black's attack may become if white's counterplay is not very active. Sometimes, white's q-side counterplay can even be ignored, even if it costs a rook or other significant material due to unstoppable mating threats.

In this position, specifically, you are already behind in development, so slowing your counterplay on the q-side may well be fatal. Right now, until you are better developed, and can see if white might somehow not continue to develop effectively, it is too early to change the attack point of white's pawn chain. If you catch up in development, and see that white cannot attack your castled king with impunity, then maybe later you can opt for c4.

A better plan is to play Ne7-c6 (it may also go to f5) and pressure d4. Other common moves in that plan will be Be7, 0-0, and possibly cd and Qb6 with Rc8 to follow.

In the line that you gave, after 8...c4; 9 Qc2 b5, instead of immediately taking on black's q-side, I think white should just continue developing to make your lack of development more pronounced. I even suggest the very "sophisticated" 10.Bg5! Be7; 11. Be3! when black has to figure out how to finish developing his k-side since 11....Nh6 is just bad there as is 11....f6. I think black is in trouble in the long run.

# Answer
> 8 votes
c4 is the usual beginner's mistake of releasing the tension unnecessarily. With the pawn on c5 you exert some pressure on d4 which can be increased with moves like Ne7-c6. When the pawn moves to c4 that pressure disappears.

If you played Ne7 instead then taking the c5 pawn is bad for white. You are not going to retake immediately but instead play Nc6. This gives white the choice between allowing you to recapture on c5 with the bishop with gain of tempo or allowing you to take the more important e5 pawn. Instead of taking on c5 white will want to develop his queenside pieces but this is awkward in the current position. His dark squared bishop is problematic.

> After 9. Qc2 b5 10. a4 a6 11. axb5 axb5 12. Rxa8

This is "hope" chess. You "hope" your opponent is going to make some bad moves and then your bad move magically becomes a good move. If you want to improve then you have to stop doing this.

Your opponent is not going to play Qc2 because if the c file opens then he wants a rook on that file not the queen. Qe2 is better. He is also not going to play 10. a4. He is going to play 10. b3, immediately attacking the front of your pawn chain.

Furthermore you are a long way behind in development with your king still stuck in the middle. You should not be wasting time on further pawn moves, particularly ones which threaten to open the position leaving your king exposed to attack. Ne7 is more to the point, developing a piece and getting you one move closer to being able to castle.

---
Tags: pawns, caro-kann
---


title: Alternative plan in the Caro-Kann

text:
# Question
Title: Alternative plan in the Caro-Kann
I'm a Caro-Kann player who is coming up against the line 1. e4 c6 2. c4.

This line has a few names, such as the "Anti Caro-Kann" and the "Quasi Panov-Botvinnik".

The books recommend 2...d5. Afterall 1...c6 prepared 2...d5. But the line 2...d5 3. cxd5 cxd5 4. exd5 Qxd5 leads to a move down variation of the regular Panov-Botvinnik, so the books recommend after 4. exd5 to play 4...Nf6 to eventually regain the pawn.

My question is, can black feasibly side-step these tricky variations with 1. e4 c6 2. c4 b5(!?). Does this reach a playable middlegame for black?

# Answer
This is a creative idea but unfortunately it does not look playable. After 7 minutes, Stockfish 5 gives the position after 2... b5 as +.87. This means that white is up a pawn for very little compensation.
> 0 votes

# Answer
I noticed you posted you'd mostly found answer for yourself in the comments, but...it reminded me of when I faced this while trying out the Caro-Kann.

It doesn't look like ...b5 works to me, either. If I were white I would play cxb5 and then let Black decide if and how to take back. There is no hurry to take on c6. The knight on b8 looks restricted, and a move such as ...a6 to force White to decide what to do with the b5 pawn wastes a move, and Black can't even get Benko-ish pressure on the a/b files unless ...c5 is played (which also gives up a move,) since White can just take back with bxc6. If black plays ...Qb6, then Nc3 (or even a4) defends the b5-pawn enough.

So from what I see Black doesn't get enough development for the pawn, and White has a pretty easy game with Nc3, d4, Nf3, etc.

When I played Black I found another pawn sac worked rather well: 4 ... Nf6 and while White can play Bb5+, Black can get it back. ...Bd7 5. Bc4 Qf7 6. Na3 Nxd5 as 7. Bxd5 Qe5 gets the bishop. This seems like a straightforward and low-risk way to equality.
> 2 votes

# Answer
b5 looks HORRIBLE. If there were not a pawn on c6, you could play a6, like in the Benko, but here, a6 would be answered by bc with a winning position.

It really does just drop a pawn for nothing as you gain no development advantage, or positional trumps.
> 0 votes

---
Tags: opening, caro-kann
---


# Question
Title: What chess app displays the name of the opening being used in the game?
I used to have a chess app that would say the name of the opening being used when you played. Then my tablet broke, and I thought it would be easy to find that chess app, but no luck.

Does anyone know what app I'm talking about, or another app that says the name of the opening being used when you play it?

# Answer
> 2 votes
It isn't likely to be the app you were using, but the Stockfish iOS app *displays* it:

(if you play more moves, the ECO code and opening name may change, to e.g. A81 Dutch defense)

I suspect many more (or even most) apps do it, or have at least an option to enable it in the settings. Stockfish does not *say* the name of the opening, though.

# Answer
> 1 votes
When you run the analysis on *Chess Play & Learn*, it displays the name of the opening.

---
Tags: opening, engines
---


title: What move did I miss?

text:
# Question
Title: What move did I miss?
I played b4. According to computer, it is a "missed win" move by me. But what move did I miss? What move should I have played? (I am white. And played b4 but I got "missed win")

# Answer
> 5 votes
After 23...Ra6? White has the option of going for an immediate kill, as black's king is in danger of getting checkmated: 24.Re7+! is a very strong move, forcing black to play 24...Kc8 (since the reply 24...Kc6?? would be immediate checkmate after 25.c4! followed by 26.Rc7# whatever black plays).

After this, white may play 25.Rc7, after which black is practically forced to play 25...Kd8 (if black goes 25...Kb8, white can play 26.a5! after which the simple plans of Rd7-d8# or Ne7-Rc8# are quite crushing) and in this situation, white may choose a few different winning plans. The most basic one is to just take pawns by either Rxb7+ or Rxf7+ using the fact that there is a discovered check. But the most crushing move seems to be 26.a5, after which black will lose at least the exchange, if not more.

A sample line: 26...Ke8 (stepping out of the pin) 27.Rxb7 (threatening Nc7, and the rook on a6 is trapped; there is no way of preventing the move, and black loses the rook on a6 for at most the bishop on b6.)

---
Tags: analysis, positional-play
---


title: Interactive Chess Whiteboard

text:
# Question
Title: Interactive Chess Whiteboard
I am a coach at a small high school. We are starting a chess club. We have Epson BrightLink projectors with the interactive boards. Is there a way we can have a chess board displayed on the whiteboard that allows a finger to move pieces while also using a pen to annotate? An example can be seen here.

# Answer
Try using the chessboard on https://szachydzieciom.pl/?page\_id=61146 in full screen mode (click the full screen icon). I know that in some schools in Poland it works well with touch whiteboards. But dragging pieces may not work. Instead you should tap the piece to move and then disconnect your hand and tap the target square separately.
> 2 votes

---
Tags: chessboards, clubs
---


title: Knight constrained in advance Caro-Kann

text:
# Question
Title: Knight constrained in advance Caro-Kann
Recently, I've been playing the Caro-Kann exclusively against 1. e4, with good results. The one line that I find somewhat confusing is the advance Caro - specifically, where does the kingside knight go?

```
[FEN "rnbqkbnr/pp2pppp/2p5/3pP3/3P4/8/PPP2PPP/RNBQKBNR b KQkq - 0 3"]

```

After 3. e5 Bf5, the bishop gets developed outside the pawn chain, which seems good for black. Something that consistently gets me in trouble is that it seems like my g8 knight has no good squares to go to.

If the knight is developed to h6, it gets captured by the bishop, and after the pawn recaptures, black is left with doubled pawns and the option to castle kingside is more or less not available after this point (the g-file is now open).

The knight obviously cannot go to f6, as it would simply be captured by the advanced pawn.

The only reasonable possibility seems to be moving the pawn to e6, then moving the knight to Ne7, but where is the knight going from here?

# Answer
> 8 votes
Where the knights go depends on your pawn structure.

One option is to do the following, at some point

* e7-e6
* Nb8-d7
* Ng8-e7
* c6-c5
* Ne7-c6

You get a French defence pawn structure with corresponding ideas.

You could go for the same pawn structure with a different knight setup.

* e7-e6
* c6-c5
* Nb8-c6
* Ng8-e7
* Ne7-f5

Putting pressure on the d4 square.

# Answer
> 2 votes
In my answer to What are the ideas behind the Short variation in Advance Caro-Kann?, I address the move Nh6, specifically:

> Black does not fear the bishop taking the h6 knight. The Bishop pair and semi open g-file provide ample compensation for the doubled h-pawns, which are not easy to attack. Often White will have to un-double these pawns for defensive purposes

So **Ng8-h6-f5** is not as odd as it may seem.

# Answer
> 1 votes
You have to take basic opening strategy into consideration. Black is playing for the c5 break in the Advanced Caro. Piece placement rotates around this break. Things like Qb6, Na6-c7/Nd7/Ne7-c6 are possible; It takes but a brief moment to review opening lines to get a feel for how one develops when playing the Caro Kann Advanced. To point out, if White exchanges on c5 you get a nice placement for your dsB. if not, you can pressure d4 and force some exchanges, weakening the e5-pawn, along with a potential queenside attack.

Good Luck!

# Answer
> 1 votes
As an avid Caro-Kann player, I would like to give my two cents. Some answers have mentioned that the knight can go to f5 with the idea of putting pressure on d4. This is in my experience not very useful. Even with a knight on c3, simply by playing Nf3 in addition to the defense exerted by the Queen, the d4 pawn is often sufficiently protected.

So the ideal position for this knight is quite problematic.

Some better ideas are rerouting your knight to c6 with the idea of pressing an additional square (e5). Also, this knight might also jump to b4 (from f5, the knight does not even have an opportunity to go to the fourth rank, other than the h4 square which will be undesirable most of the times).

Another position which is often suggested by computers is g6, although I cannot tell what the knight can do there.

---
Tags: opening, caro-kann
---


# Question
Title: Hanging square and deflection tactic leading to a back rank checkmate
```
[FEN "2r1r1k1/5ppp/8/8/Q7/8/5PPP/4R1K1 w - - 0 1"]

```

The important square of e8 square is hanging. It is hanging because if white can take that square it's checkmate. Is this a hanging square tactic?

If the rook on Rook on c8 is deflected from the protection of e8, is it called a deflection tactic?

```
[FEN "6k1/3qb1pp/4p3/ppp1P3/8/2PP1Q2/PP4PP/5RK1 w - - 0 1"]

```

Here, the important f8 square is not hanging, so white plays Qf7+ to deflect the king from protection of f8 square, thus leading to checkmate.

# Answer
> 1 votes
I haven't heard of the term "hanging square" before. But you're right that the c8-rook would be deflected (or "attracted") if it were taken away from defending the rook on e8.

---
Tags: strategy, tactics
---


# Question
Title: Convert Stockfish analysis output to pgn
It seems that there is no way to direct see Stockfish’s analysis in pgn when it evaluates a position. I am looking for a way to convert the SAN or LAN format into a PGN. Maybe it will work in Python. Does anyone know of a way to do this conversion?

# Answer
> 1 votes
If you're in chessbase you can right click on Stockfish (where it displays its lines of evaluation), and press "Copy to Notation".

---
Tags: stockfish, pgn
---


# Question
Title: Opening the e-file in King's Indian Defense?
I'm reading about KID in "The Complete Book of Chess Strategy" by Jeremy Silman, and I don't understand one of his points. He gives the following moves (which is the "Averbackh Variation"):

1.d4 Nf6 2.c4 g6 3.Nc3 Bg7 4.e4 d6 5.Be2 0-0 6.Bg5 c5 7.d5 Qa5 8.Bd2 e6

Which he says (of Black's plan) "...opening the e-file for his Rooks". But I don't see that. There's no way white would go 9.exd6 when 9.exf6 is there, unless we are talking a Knight sacrifice with 9.exf6 exf6. But even then, the e-file is not totally open with a Bishop at e2.

So I guess my question is if I'm reading that right, or if there is maybe some typo/error here. Black sacrifices his Knight for a partially open e-file?

# Answer
> 3 votes
I am not sure if you are leaving something out, but what he means is that depending on what white does, assuming it does not lose, black may play e6xd5 and then Re8 to get play either against e4 if white recaptures with c4xd5, or possibly other play down the open file should white respond to e6xd5 with e4xd5.

I also think you may be misreading the notation since there is not going to be exd6 or exf6.

---
Tags: kings-indian
---


title: Why isn't Chess960 the standard?

text:
# Question
Title: Why isn't Chess960 the standard?
Bobby Fischer said that standard chess is dead and I believe him. Current players rely too much on engine-moves and theory in the openings and quite far in the middle-game without any real calculations, but memory. For instance, Carlsen had memorized engine-moves far into the middle game against GM Sergej Karjakin when playing white, which I find unfair.

Chess960 allows for 960 different positions to begin the game and no GM would be able to analyze every start to the current extent. Thus, Chess960 would rely on raw talent and calculations. Why isn't it the standard nowadays?

# Answer
> 27 votes
Chess players identify with their openings, all chess clubs have that one guy who always plays stodgy London stuff with white, the maverick with all his dodgy gambits and the youth player with 25 moves of Najdorf theory memorized for the day he finally gets to play it.

Opening books are by far the most sold type of chess book, and the number of titles is much larger than that of other types of book. People write hundreds of pages of grandmaster level analysis on a line that starts on move 6 and still lots of amateurs buy the books.

When an amateur watches a grandmaster game live, he uses knowledge of the opening played to understand what is going on. If they play a King's Indian and the center is locked, one of them is going to attack on one wing and vice versa. If it's a closed Ruy Lopez, we know there's probably a slow maneuvering game coming up, et cetera.

Playing memorized opening theory gives the amateur the feeling that for that part of the game at least, he is playing at grandmaster level.

In other words, **chess players *like* opening theory**.

# Answer
> 11 votes
To start with, standard chess in its current form has been the standard for a well over a century. It is well known and well established. It also enjoys a fair amount of popularity. It is widely seen as a test of intellectual prowess (even if that prowess often fails to transfer to other fields) in which luck has no effect in the game (even if that's not 100% accurate).

Assuming the Wikipedia article about Chess 960 is accurate, Fischer announced his variant to the world in 1996. Thus 960 is still relatively new and unknown. While I've been playing chess off and on for 45 years, I've still never played Chess 960, nor even watched one game. I suspect that if you asked the average person on the street what Chess 960 is, they wouldn't be able to provide an accurate answer. I also believe that a lot of people wouldn't like a game in which the pieces start in different positions every time; especially one they've already known which always starts with the pieces in the same positions. Additionally, luck can play a part in the game, which takes away from the purity of intellectual prowess that attracts some to chess.

Overall, this is my way of saying that standard chess remains popular; I'm certain it has more broad popularity than Chess 960. Also, it is a more established history than 960. Time will tell whether 960 increases in popularity, stays an interesting variant of the standard game, or turns out to be a fad. However, given standard chess' head start, I believe it will continue to remain the standard for the foreseeable future.

Also, as noted by lenik's answer, chess is enough of a challenge for most of us who play it.

# Answer
> 9 votes
99% of the chess players will never reach 1500 rating, so for them the standard chess is quite good enough. Chess960 is interesting variation along with "atomic" chess and others, but the niche is quite small and I'd say it's dead as well as its inventor.

# Answer
> 5 votes
Chessbase once published an article that touches on this question.

Chess960 introduces very alien positions, such as this one.

```
[FEN "bnqrnbkr/p2p1ppp/1p2p3/8/2PN4/1P6/P3PPPP/BNQR1BKR w - - 0 1"]

```

Chessbase's comment on this is:

> Here's another example: Svidler \[Black\] is still wondering, on move five, if he can move a pawn and not lose instantly, while Anand is pondering his 22nd move in a very interesting position. In the commentary booths, the GMs were discussing Anand's options with great excitement – he seemed to be struggling to equalize with white in a Sveshnikov! They were completely silent on the Aronian-Svidler game, as nobody had the faintest idea of what was going on. I think it was Tim Krabbé who compared commenting on a Fischer Random game to conducting a guided tour of an art gallery that you are visiting for the first time. Very apt.

Another problem with Chess960 is that some positions are more unbalanced than the traditional starting position. While some positions are also more equal, there are a few positions which start with more than twice the "normal" White advantage.

The final problem with Chess960 is that there's no continuity. If you play the opening position and lose to a spectacular new idea, you can study it back home, analyze where you went wrong, use the idea yourself, see if someone else can come up with an idea to beat this idea. In Chess960, nothing of this sort applies. Misjudge the opening and lose? Who cares, you're probably never getting the same opening again anyway.

# Answer
> 4 votes
For one thing, this would make tournaments and rankings a bit difficult because the games are not identical.

How would you rank someone who won many games with more active starting positions compared to one who won other games with more passive starting positions? One player might be better at one type of game, while another, better at a different type. (Of course one *can* say this is actually a good thing...)

Also, adding to what GreenMatt wrote (that the current one has been around for much longer), Chess is popular not only because it's an interesting game, but because it's popular - *everyone* is playing it. There are other interesting games, and I assume you'll find some fans of those games who will tell you they're better than Chess. But popularity is self fulfilling. Just like (other) marketing. You'd have to convince many people to switch in order to convince many people to switch.

# Answer
> 4 votes
There are a number of reasons. In no particular order:

1. Top players are still able to find interesting opening novelties. Therefore to them, chess is not yet "played out." As time goes on, it will get more and more difficult, and the interest in FischerRandom will increase.
2. Amateur players overwhelmingly do not seem to like Chess960 compared to professional and top players. This was mentioned by WGM Jennifer Schehade. While GMs are able to navigate the increased complexity of chess960, amateurs do not have their usual reference points and memorized moves, thus it puts them into a deep think from the very first move, and so is more difficult.
3. There are a couple hundred years of the standard chess opening, and this has ingrained itself in the minds of many players, who have memorized a lot of openings. They fear losing out on all this knowledge, firstly, but secondly, because they are so familiar with the initial starting position, many persons feel it is more "harmonious." You will find other emotional terms frequently mentioned, whereas it likely just comes down to familiarity. Had there been a different start position for the past couple hundred years, people would be attached to it just like they are to the current position, and rationalizing it as the best starting position.
4. Publishers and writers of opening books have a vested interest in chess960 not succeeding, because it would mean an end to their book sales. There is, eg, one prominent opening authority who has denigrated chess960 repeatedly. It could also be that they are attached to the beauty of current opening theory.
5. The problem with draws and memorization of moves is only relevant for the chess professionals and chess fans. To anyone who has not played in a tournament, the game has plenty of complexity.
6. While chess960 is the most common chess variant, there are always adherents of others which prevents any one from gaining undisputed status - eg, Seirawan-Harper chess, Finesse Chess, Capablanca chess, Bronstein chess, and so on.

# Answer
> 3 votes
If one is to modify the game of chess to make it more dynamic, the question becomes why choose Chess960? There are many options beyond that particular choice, for example Chess480.

Many also dislike the exact specifics and typicall playing dynamics of Chess960 and have proposed changes. Specifically, for example, the castling rules.

I personally hope the rules of chess continue to evolve, but I hope they evolve in a less dramatic fashion than Chess960 proposes.

Still, I believe that 'classical chess' will be around for a long time, and I don't think Chess960 has yet established itself as the only viable extension of classical chess.

There are many chess variants, some of which are quite close to the usual game.

See Wiki: Chess Variants

---
Tags: chess960
---


# Question
Title: How did the Fried Liver Attack get its name?
Many chess openings get their name from a player who invented it and/or played it and/or documented it. Place names are also frequently used, denoting where an opening was first played or became prominent, or perhaps where players who used it were from. Other openings may take their name from some sort of description of style or some other feature of the opening.

The Fried Liver Attack doesn't seem to follow any of these patterns. Where does the name come from?

# Answer
> 15 votes
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".)

---
Tags: opening, terminology, fried-liver-attack
---


# Question
Title: Does permanent loss of castling rights reset three fold repetition?
Threefold repetition requires that the same "potential for moves". For example, if an en passant move could be played in one position but not another, it does not count as the same position.

With respect to threefold repetition, would the positions be considered the same if:

* In the first position, the king cannot castle because it is in check, pieces are blocking, or for some other reason, but it could castle otherwise.
* In the second position, the king cannot castle because it has already moved.

# Answer
> 11 votes
According to the FIDE Laws of Chess:

> 9.2.2 Positions are considered the same if and only if the same player has the move, pieces of the same kind and colour occupy the same squares and the possible moves of all the pieces of both players are the same. Thus positions are not the same if:
>
> 9.2.2.1 at the start of the sequence a pawn could have been captured en passant
> 9.2.2.2 a king had **castling rights** with a rook that has not been moved, but forfeited these after moving. The castling rights are lost only after the king or rook is moved.

Hence the answer to

> With respect to threefold repetition, would the positions be considered the same if:
>
> In the first position, the king cannot castle because it is in check, pieces are blocking, or for some other reason, but it could castle otherwise

Although castling is temporarily prevented the king still has **castling rights**. They are not lost if castling is temporarily prevented by check or blocking pieces. They are only lost if the king or rook moves.

With regard to:

> With respect to threefold repetition, would the positions be considered the same if:
>
> In the second position, the king cannot castle because it has already moved.

The rules are clear. If the king has lost castling rights since the the first position then the positions are not the same and a draw cannot be claimed.

> Does permanent loss of castling rights reset three fold repetition?

Yes. That's what the rule says.

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


# Question
Title: Creating chess engine, machine learning vs. traditional engine?
I am both an avid chess player and computer programmer. I would say that playing chess and programming are the two things I spend the most time doing. Naturally, I am wanting to create my own engine and, ultimately, Lichess bot.

In wake of AlphaZero's crushing performance against Stockfish last year, I am considering whether I should create this engine with machine learning (some type of neural network, possibly using Tensorflow) or traditional, hard coded heuristics.

I am less familiar with neural networks than other kinds of hard-coding. Still, it could be a good way for me to learn to work with neural networks.

Another thing I am considering is whether it is important which language I use to code the engine. I know many chess engines use C++, which I have never used before. I have used other C-based languages which do many of the same things, with mostly varying syntax. I am most familiar with Swift and Javascript, but am also familiar with Python and feel that it could do the trick for me.

So, in terms of creating the strongest chess engine possible, should I go neural network or hard-coded?

**Update:** I am writing a traditional engine in C++. It is currently *somewhat* UCI compatible and plays at what I estimate is 1100ish ELO. But it generates legal moves and I’ll be posting updates here.

This is the link to the github repo for the engine. Feel free to fork and make PRs, or just make general suggestions/tips.

# Answer
# First step: Define your goals/reasons

I think this is the predominant factor. Which of these best fits you? *(Choose **only one**)*

1. You want to enjoy a fun, challenging coding task
2. You want to create an extremely good chess engine
3. You want to learn about how chess engines work
4. You want to learn/practice coding skills
5. You want to learn/implement computer science concepts/theory (e.g. machine learning)
6. (Other)

IMO it's fine to "toss a coin" for anything except 2. For all the others, you will meet your goal whether you choose ML or hard-coding. However you probably want a comparison between the choices to help you decide.

# The case for hard-coding

Playing chess (as a human) involves logical thinking. You explore the space of possible actions you and the opponent can take. This has spawned a field called *game theory* which contains theoretical frameworks for analysing games in general.

If you enjoy working with details and being specific and reasoning about things then this could work well for you. In comparison, machine learning involves a lot more "black box" algorithms which are fuzzy and opaque. You don't know exactly what is going on.

Also I reckon you will have an easier time "figuring it out on your own" if you go the hard-coding route rather than machine learning. Less copy-pasting stuff you don't fully understand.

# The case for machine learning

It can be exciting to give birth to a creation and watch it take on a life of its own. While hard-coding is all about precision and detail, machine learning is flexible. Take away some neurons and the result will probably be similar.

Hard-coding is about studying chess. Machine learning is about studying the creature you have created.

And machine learning is, of course, a very hot topic.

# Language choice for hard-coded

I am not sure what you mean by "other C-based languages". C++ is the only mainstream language that is anything like C. The advantage of C/C++ is that they are *fast*. Although other languages have caught up over the years, C++ still gives them a run for their money.

C++ isn't easy. You will get great performance out of more modern compiled languages like Rust, Golang or Swift. But it shouldn't be much worse if you go for a JIT language. I.e. **don't use the CPython interpreter**; use IronPython or Jython, or Node, or C# or Java.

GPU programming requires a different approach and I would advise against it at this point.

# Language choice for machine learning

The problem with TensorFlow is that it is very low-level. It is more about writing number-crunching algorithms (which can be farmed out to parallel hardware) than about an interface dedicated to machine learning.

Of course, it can be a great learning experience! And is certainly very worthwhile learning today. However, you may want to start with Keras or PyTorch.
> 12 votes

# Answer
If you're trying to make the strongest engine possible, absolutely go for NN engines.

Traditional engines are great - Stockfish is arguably still the strongest engine on the planet on consensus equal hardware - but they are hard to write. These engines didn't get where they were overnight; they took years and years of work. Stockfish for example has been steadily gaining elo for six years. If you start from scratch, you will not get anywhere near Stockfish strength quickly; in fact you are likely to stall several hundred elo from where Stockfish currently is. For comparison some of the strongest single-author engines right now are Ethereal, Laser, and Xiphos (I neglect Houdini & Fire since they aren't open source). These engines are all substantially weaker than Stockfish.

Why are they so much weaker? Two reasons:

1. At this level, developing an engine takes a lot of computational power. What you do is look through your code and identify an idea that could gain elo. An example idea is, "if we know this move is probably good, do not search branches that reverse that move" (if this doesn't make sense to you, it means there's going to be a high learning curve as well). You then write a patch that implements the idea, and test the modified engine against the previous version. At this level, it takes tens of thousands of games to get a large-enough sample size to tell if the patch is effective. Playing these games takes huge amounts of computational power. Stockfish has access to super hardware: as of time of writing, the Stockfish testing ground Fishtesting is running with 1038 cores. For comparison a typical desktop computer might have 4-8 cores.
2. The other reason is that Stockfish is backed by many brains. As of time of writing, there are 8 patches written by 5 people being tested. If you look through the patch histories you'll find many more developers who've written patches. I don't know how many active Stockfish developers there are, but it's certainly \>20.

On the other hand, NN engines (relatively) easily reach a strength that's well above Ethereal/Laser/Xiphos. See for yourself in the latest Top Chess Engine Championship tournament. Ethereal/Laser/Xiphos are in League 1, which is credible enough, but the engines in the top division (Division P) are:

* Stockfish (community-backed traditional engine, runs with Fishtesting)
* Komodo (commercial traditional engine, has full-time developers)
* Komodo MCTS (commercial semi-traditional engine, has full-time developers)
* ~~Houdini (commercial traditional engine, is a one-man effort, hasn't been updated for two years)~~
* Leela Chess Zero (community-backed NN engine, runs with the analog of Fishtesting aka a ton of hardware)
* AllieStein (2-man NN engine)
* Stoofvlees (NN engine)
* ScorpioNN (NN engine)

The last three engines - AllieStein, Stoofvlees and ScorpioNN - are all small collaborations by people who, as far as I know, are enthusiasts like you and not full-time developers. They've gotten to Div P strength after less than two years of trying (all these NN engines only appeared after AlphaZero). Nobody single author has ever written a traditional engine that competed successfully with Stockfish/Komodo.\* ~~For comparison, in the recent history of computer chess there has only been one person who's ever written a traditional engine that competed successfully with Stockfish & Komodo on his own (Robert Houdart, the author of Houdini).~~

It's true that you probably won't have the hardware to compete with Lc0, but Lc0 takes this much computational power because it's a "zero" engine - it's supposed to play chess without any kind of human knowledge except for rules. You don't need to use the same methodology. You could use e.g. the Stein methodology that uses supervised learning. It's arguably even better than going "zero" - after all it's AllieStein playing in the superfinal, not Lc0.

The upshot is: **if your aim is to compete with the best engines in the world, you are far more likely to succeed with NN engines than traditional ones.**

\*It might look like Houdini is such an example, but Houdini is plagiarized from Stockfish.
> 26 votes

# Answer
> So, in terms of creating the strongest chess engine possible, should I go neural network or hard-coded?

Don't choose a NN unless you have access to ridiculous(A few hundred Nvidia V100s). Training a NN to play chess takes so much hardware. See the people contributing to Lc0 to train over 200 million games. Since you will probably have trouble accessing the hardware (you could try to get some at Google Colabatory, but with only that, training will be very slow).

**Edit: Using a NN With Supervised learning, you MAY get away with just Google Colab and possibly one strong GPU (2080, 2080Ti, Radeon VII).**

> Another thing I am considering is whether it is important which language I use to code the engine. I know many chess engines use C++, which I have never used before. I have used other C-based languages which do many of the same things, with mostly varying syntax. I am most familiar with Swift and Javascript, but am also familiar with Python and feel that it could do the trick for me.

Python and Javascript are probably too slow for a strong chess engine. I haven't used Swift but it probably won't like platforms other than macOS, so it's probably better to use C or C++. You could also possibly use Rust, but that has many safety features that get annoying and you don't really need, which can get annoying. It's also going to be harder to get good performance out of it since certain low-level optimizations are hard to make. Of course, you can always write it in assembly but that's probably going to be too much work. see https://www.chessprogramming.org/Languages/
> 10 votes

# Answer
I built a purely toy chess engine using: python chess it was really nice not having to code the rules of the game myself and just focus on the logic; however, the number of position I was able evaluate per second is very low. This might be a good starting point.
> 3 votes

---
Tags: engines, programming, computer-chess
---


# Question
Title: How to tweak a chess engine like SF to return a variation which is only slightly better than your moves?
By default, engines return the strongest variation(s) they calculate. I was wondering if there is a way to tweak an open source chess engine to show a move from their MultiPV which is slightly better than or equal to your moves. Let's say the evaluation stays only +2 consistently through the game. Instead of the strongest move in a position, the engine is retuning back the move with +2. Is there a way to do this?

\[edit 3.10.2019\] in case of a blunder (e.g. +3 jump in the engine evaluation, the engine can keep the difference and continue the game with +5 instead of +2).

\[edit 4.10.2019\] I found that on https://lichess.org there are levels for SF. Right now, level 5 corresponds to ca. 1700 elo, level 6 is 1900, level 7 is 2200. This satisfies my needs and closes my question. Thank you

# Answer
> 2 votes
Ok, so say the engine plays a move with white and values the position as +0.50 (slightly better for white). So now the human plays as black, and blunders a bishop. The engine now values the position as +3.50, but you want to play a move as close as possible to +0.50, v. g. +0.60. Is it what you're looking for?

In that case it seems the way to go is (from the POV of the engine); "the position after my last move was +0.50, so in the current position, if a move that improves that eval exists, I must play the one closest to +0.50. Otherwise (there isn't a move that improves my eval after my last move), play the best move available." If this is your idea, I guess this is doable, and for someone who develops their own chess engine probably shouldn't be hard to code.

Maybe the idea can be improved. For example, if you blunder a bishop, probably it's a good idea the engine to grab the bishop than to play something really stupid.

In any case, I think it's definitely doable, probably with some refinement. (For example, it's not the same blundering a bishop in one than losing a bishop after a 10 moves combination; in the first case, IMO, the engine should take the bishop, but in the second one it should chose a sub-optimal move).

---
Tags: engines, learning, software, stockfish, open-source
---


# Question
Title: How does an engine choose between two moves of equal evalulation?
In many positions, different moves are functionally the same, and an engine should return the same evaluation. For example, in a KR vs. KR endgame, (almost) every move that does not lose the rook should give exactly the same evaluation: 0.00. How does an engine choose between them then?

# Answer
The answer is simple for traditional engines like Stockfish and the like: if multiple moves have the same evaluation, they pick whichever move was searched first.

All strong alpha-beta engines employ move-ordering heuristics which guess the moves that are likely to be strongest in a position, before actually searching those moves. This is advantageous because the best case for alpha-beta search (especially for PVS) occurs when the strongest move is searched first, allowing beta cutoffs to occur as soon as possible and also avoiding repeated searches.

So when two moves are found to have the same evaluation, the tie is broken by move ordering heuristics.

Evaluation granularity also plays a role. Stockfish evaluates positions to the nearest 1/256th of a pawn, but only reports evaluations in 1/100th of a pawn, so there could be internal differentiation which is not visible to a user. MCTS engines like Lc0 make decisions based on the number of nodes searched in the subtrees of each move. This information wouldn't make sense to report as centipawns, so a conversion function is used. If many nodes have been searched, multiple moves may map to the same centipawn evaluation even if they can be differentiated internally.
> 4 votes

# Answer
Some engines uses three decimals in its evaluation. That's how can introduce a difference. I have read that its in use a technique to add a really small but ramdom number, to make them different. Don't have the references at hand, but can be known from the read.me of every engine.
> 2 votes

---
Tags: engines, evaluation
---


# Question
Title: Where did Bobby Fischer live in New York?
Where did Bobby Fischer live in New York in his younger years? Is anyone able to locate the street address where he lived? Is it 1059 Union Street in Brooklyn from the famous 1951 Helms letter to his mother?

# Answer
> 6 votes
In 1955, his address was 560 Lincoln Place, Brooklyn. Source:

http://tartajubow.blogspot.com/2015/09/bobby-fischer-lived-here.html

# Answer
> 6 votes
Bobby Fischer lived here at Lincoln Place 560 in Brooklyn. The video shows the inside of the building. I was there in September, 2019.

---
Tags: fischer
---


# Question
Title: How large can a rating difference become before either player realizes it's not worth engaging in a game?
I think the relationship changes as rankings increase. For example, players with ratings lower than 1000 might be able to play all other players in that range and still enjoy themselves, but if a sub-1000 player matched up with a 1400+ player, the two might not enjoy themselves in the same way. At which levels do players begin to learn strategy and stop making mistakes?

# Answer
One thing is, I think there may be real surprises even if the rating range is quite vast. You'll never know the real strength of an opponent most of the times (because of lack of rated games etc.,) On another perspective, lets say one of the player is 1400 Elo and the opponent is 2000 Elo, it will still result in a good "feeling" for both the players if they take it sportively. The 1400 Elo player will clearly appreciate the consistency in the 2000 Elo player's moves and will really learn a LOT. The other way round, it is a good opportunity for the 2000 Elo player to test out his skill or experimenting things which he would not dare against a player of his own caliber (Like for example sacrificing the Queen for a Knight and Bishop and trying to win in the given situation).

So I feel there is no rating difference that can make the chess game not worth engaging, if you look at the bright sides.
> 4 votes

# Answer
I have heard a rule of thumb is to have a coach at least 400 rating higher than the student. This suggests that at a difference of 400 the higher rated player will have a much deeper insight into her opponents game than the lower rated player has in his own game. That doesn't mean upsets aren't possible, the 2014 Olympiad commentator on Chess.com today said he dropped below 2500 due to losing to a 1940 in his most recent game.
> 3 votes

# Answer
Off the top of my head I believe 700-750 rating points is the point where ratings don't change. So, at about a 700 point difference the superior player should win every game. Granted, anything could happen in an actual game.

A beginner has about a 1 in 40 chance of playing a gm move by accident (given 40 legal moves in a position). Its not inconceivable that they could play several really strong moves in a row and end up in a very good position. At the same time, a very good player could be distracted or overplay the position and play some weak moves. Anything's possible.
> 1 votes

---
Tags: learning, rating, training, elo, etiquette
---


title: Beginner Openings/Defenses to learn

text:
# Question
Title: Beginner Openings/Defenses to learn
What are good openings/defenses to study for both black and white for beginners. I've messed around with the sicilian defense and it is not bad, there's just so many variations and different types of defenses/openings its overwhelming. I understand the only way to learn is to play one for a little while. Are there any sites with virtual chess boards that show step by step examples of some of the popular styles. It's not easy to learn when all you get e4, e5 nf3 etc. Are there any viable openings for white other than d4/e4, these seem overused and very cliche

# Answer
> 7 votes
In my opinion this is a pretty hard question to answer, because there is no single correct answer to it.

The choice of opening repertoire for a player should be determined by his play style, e.g. do you prefer to be aggressive always on the offense or are you more of a tactical player, looking for strategic weaknesses in your opponent's position, do you prefer closed over open positions, etc.

So my answer to your question would be to follow the basic principles of opening play:

* *control the center;*
* *develop your minor pieces to their best squares;*
* *get your king to safety;*
* *do not move a single piece too often in the opening, unless there's a pretty good reason to do so;*
* *do not bring your queen out too early.*

From there on pick an opening that fits your play style and study the ideas behind it, not just memorize the moves, understand what each of them accomplishes.

> Are there any viable openings for white other than d4/e4, these seem overused and very cliche

These opening moves are most certainly not cliche. Although you might see these moves as the first move in almost every game there are lots of variations that follow. Therefore my recommendation for you would be to play an opening from the family of The Italian Game as White and maybe The French Defense as Black.

From my experience as an amateur I came to the conclusion that one shouldn't focus too much on openings. After you pick an opening that fits your style, focus on the endgame and various tactics and strategic ideas. This seems to be more efficient in the long run.

Good luck!

# Answer
> 3 votes
When I was just starting out in chess, I was barely able to beat people low rated, Thats very very low. But slowly, and with much practice, after about 1000 games of chess with little opening/defense knowledge, I was able to reach the mid 1200's quite easily. To make the new transition over to the 1300's, I had to try even harder to remember openings and tactics. The self training took me months, and plenty of hours out of my spare time, but I learned enough opening knowledge and pawn tricks to improve way over 1300.I wondered what the best types of openings and defences would have helped me the most along the way. Well, after careful analysis, I have concluded that 5 different openings were the best for me to use during my "beginner" days. Be aware that ALL of the openings below have been used and tested by many GM's, and are in use in today's most serious of tournaments. Below are the openings, and the reasons why beginners should use them =\]

```

[FEN ""]
     1. e4

```

1.e4 * Kings Pawn Opening is the most widely used opening in chess, because of the feature to open up both the light square bishop and the queen at the same time. Also, the pawn grabs for the center, causing tension for black. After moving e4, just develop your minor pieces and you should do fine.

```

[FEN ""]
     1. d4 Nf6

```

When playing as black, if white should make their first move d4 (queen's pawn) then you should try to use this move fairly often. In most games, the knight moving to Nf6 is inevitable most times, so doing it first will save you time in the long run. Don't try this when white plays e4, because that would transition to the Alekhine defense, a much more advanced defense ;)

Please be aware, this is only a recommended read for those under 1200 in rating, and basically only just starting out in chess. Of course, those above 1200 can read this and learn something new, but those of you above 1200 should seek Intermediate opening guides that are recommended for those between 1250-1400.

# Answer
> 3 votes
Knowing which openings to study can be a pretty daunting task.

My advice would be to not take on too much at once. There are a huge number of openings and if you try to take on too many you'll end up being overwhelmed, and won't learn anything.

When first learning opening you're best to go with the odds. Learn opening that are likely to come up more often first. I don't have exact figures to back anything I'm saying up but when I started to learn openings I decided to learn one basic opening as white, and two as black (one in response to e4 and one to d4).

As white I tried to stick to the Scotch Game. Again. I can't back it up but sticking to a fairly standard opening seemed to happen more often than with a lot of other games. There's no point focusing on depth, because you'll rarely see the line you want. Instead, learn the first three moves and as many variations and responses you can think of. Then work on going to 4 moves deep. You'll find your repertoire being used a lot more than if you learn one variation to a depth of 8.

It doesn't really matter what openings you use but like I said, go with the odds. There's plenty of software or web sites that tell you the most common reply to e4. Then the most common reply to that etc. etc. until you're pretty proficient at the most common outcomes. Then you can worry about less common variations.

# Answer
> 1 votes
White- Bishop's opening (very versatile). Alapin and exchange variations vs french.ck, alekhines. Main lines vs cc and nimzo. 150 attack vs pirc/robatsch.

Black- vs e4 play the classical vs the Ruy and against everything else look for lines that play a quick d5.

d4- Choose between either the tarrasch or dutch. Both are system-type openings in that you can play them against anything.

This is a very simple opening rep that allows you to get playable games against almost anybody while at the same feeing you up to study the parts of the game that will give you the most improvement.

# Answer
> -1 votes
The d4/e4 openings are definetly not overused. They are used because they are the best openings. You should learn the stonewall attack and there is a great video on youtube about how to defend d4.

---
Tags: opening, defense
---