How many positions per second can a modern supercomputer calculate? If we created a very powerful supercomputer (as powerful as the current most powerful supercomputers) which was only designed to find forced mates, how many positions could it calculate per second?

I only need an approximation. And remember, the computer doesn't waste time evaluating every single positions (like normal engines do); it just calculates as far as he can until he finds a forced mate (if there is any).

I tried to find the answer to the question myself, but I'm not sure at all if my conclusion is correct. So what follows may be wrong.

I found that the supercomputer Deep Blue "was capable of evaluating 200 million positions per second" (from Wikipedia).
But Deep Blue was old, supercomputers have became much more powerful since 1997, and Deep Blue wasted time evaluating every positions.
Therefore 200 million is only a lower bound for the answer to this question.

Since Deep Blue had a performance of 11.38 GFLOPS, and the current most powerful supercomputer (Tianhe-2) has a performance of 33.86 PFLOPS = 33 860 000 GFLOPS, we could estimate that the answer would be closer to 200 000 000 * 33 900 000 / 11.38 = 6 * 10^14 = 600 trillion positions per second. That seems like a lot, but taking into account that in average a position has around 35 legal moves, given 3 minutes such a computer would only be able to calculate every single positions up to a depth of 11 plies. Since Deep Blue wasted time evaluating every single of those 200 million positions per second, I believe Deep Blue should have been able to calculate approximately a billion positions per second if it didn't have to evaluate them.

So the true answer to the question is probably closer to 3 * 10^15 = 3 quadrillion positions per second. That's still not much: given 30 seconds it would just be able to calculate everything up to a depth of 11 plies. Even given an entire year it would only be able to calculate every positions up to a depth of 15 plies.

To answer the question in the title: In chess programming, perft is used for debugging move generators and testing their performance: the goal is simply to calculate the number of possible ways the game could continue until a mate or a stalemate for the next N moves. Modern engines give around 10-100 million nodes per second using one core of a modern processor. This program apparently searches 20 billion nodes per second using a modern GPU instead of a CPU.

However, as I said in the comments, searching for a mate in N moves is very different than searching all possible moves until that depth. The following observation is the heart of alpha-beta pruning: for example, if you have found that after 6.Nc3 Qxb4 7.Nd3 white can mate, there's no need to see what happens after 6.Nc3 Qxb4 7.a4.
Another, perhaps more likely example: You have found that the position after 5.e3 is drawn, and then find out that 5.e4 Qc7 gives a draw, too. Now we already know that the position before 5.e4 is at least a draw for white, and find out that the position after 5.e4 cannot be a win for white. Because it does not matter whether white draws or loses after 5.e4, we don't have to see what happens after 5.e4 Qb6.
As you probably can see, move ordering is critical here: it is beneficial to search best moves first. In fact, with perfect move-ordering, alpha-beta can reduce the number of searched nodes to approximately square root of the original value. So with perfect move-ordering, the number of positions needed to search for mate in 10 plies would be 35^5, not 35^10. But to get a good move ordering, one needs to do something else than just generate moves: perhaps evaluate the intermediate positions to get a good hint of the values of the moves. Of course, for the search of mate in, say, 20 plies, the best evaluator function would probably be different than what is used in engines designed to play a full game of chess.

I am unable to comment so im commenting here. Do you assume the computer starts calculating from the very beginning of the game or from a middle-endgame position? From the very beginning it would be impossible to find a forced mate because if both sides were to play their best lines it would be a draw. Lets say for example that out of the infinite chess mate positions possible it comes up with the fools mate first. If your computer were to calculate to find the first available mate it would find that. The question would be better asked if you have a move min or max to help centralize the math.

Potentially super computer in the future will have unimaginable processing rates and they will progress in their ability until infinity would we conclude then computers could calculate infinite amount of moves in a second? It was good you defined your parameters in the beginning by keeping the processing power limited to today's limits.

As refered to in the first comment the question should be how many positions a comp can generate in a second. To analyse a move and its infinite amount of possible positions would take infinitely long.

I might be rambling on at this point but i just wanted to ask a few questions to help refine your questions.


When is a queen better than 3 minor pieces (or vice versa)? Obviously a lot is going to depend on the exact position, but I'm asking if there are any general signposts - e.g. bishops usually get better than knights if the position is open, or in an endgame, but I can't say the same about Q vs 3 minors.

The queen does a good job when there are a lot of weaknesses to attack, especially if the opponent's king is out in the open, so there are a lot of options for double  attacks.
The pieces are generally stronger if they can coordinate and the king is still relatively safe. Earlier in the game that's usually the case.

I am presuming things such as pawns, bishops and knights count as minor pieces for what my answer will be.
Queen > 3 Minor Pieces

In the case that there is a way that you could get a checkmate, but you need to make a risk with what your opponent will notice and what he/she won't notice. You could try to put 3 pieces to get your opponent to take those helping you to get your checkmate. Then there is the case for AI which takes every place into consideration. For AI it would have to be pawns or perhaps making it be that your opponent is forced to take certain pieces.

For the second for AI 'forcing your opponent to take certain pieces' with that I mean that they are in a check or that piece being there is going to lead to a checkmate.

In the case that you want a minimal risk then I would say it would be best to save your queen and try to keep it because it can help create many forks.

3 Minor Pieces > Queen
With 3 minor pieces there is the obvious case getting 3 pawns to the end to become queens, but I will presume that it would be banned for 2 reasons.

It is more challenging and move and noticeable.
It is making a minor piece become a major piece.

With three pieces there are more combinations that you can use to get a checkmate, or defend your king. If the opponent's king is trapped with their own pieces then you can use just your knight to get a checkmate where as it would be hard to get a checkmate with your queen for it would need lots of setting up.

generally speaking with 3 pieces is good due to numbers
I am not saying that one of them is always better. I am just stating the cases. If I had to pick between the two in a case that I don't know as in I can't see the situation for some reason I would go for keeping 3 pieces instead of losing my queen.
Keep in mind that people have their play style. You might prefer keeping your queen or keeping 3 minor pieces depending on your play style.


Knowing when to play Nc6 vs Nbd7 in the Najdorf Sicilian as black? I've been studying the Najdorf Sicilian for some time, and I generally have a good idea of where to develop my pieces to. My light and dark square bishops typically end up on e6 and e7, respectively. I'll castle short and my rook will ultimately end up on c8. One thing I struggle with, however, is deciding whether to play Nc6 or Nbd7, and what elements make one choice more attractive than the other.
I understand that each move has its own strengths and weaknesses. Nc6 gives the king knight the ability to retreat to d7 at some point with prospects of pushing the f-pawn. It however blocks off the semi-open c file that is typically pointing at the white king. Nbd7 supports the knight on f6, but also takes away its ability to retreat to d7. Another benefit is that it keeps the c file clear for black's rook. Nbd7 also blocks the queen's defense of the d pawn.
Consider the following position I faced against the obscure Adams attack variation:
rn1qkb1r/1p3pp1/p2pbn1p/4p3/4P1P1/2N4P/PPP1NPB1/R1BQK2R b KQkq - 1 9

Engines slightly prefer Nbd7 in this position to Nc6, though my intuition would tell me to play Nc6 before considering Nbd7. How would you go about deciding whether to play Nc6 or Nbd7 in this situation? Also, are there any good games that are instructive on this subject?

Well it all "depends" on the position, but in the given example,   Nc6 is a better option as it has a possible outpost on d4 or b4 and with the rook on c8 it will also be doubly defended. It can even be re-routed to f6  if required which would be almost impossible from d7. Nbd7 does block the defense of the d6 pawn. BTW , I  saw a study somewhere that countering the najdorf the d6 pawn is to be targeted therefore it is suggested not to make it a liability in the first place ( of course this might be valid in high level games only). Here is a study where majority games I saw played Nbd7 but I am not a GM and can't quite follow the reasoning. If your opponent castles long then definitely put the knight on d7.

It all  depends.  There is no rule.
What is your preferred strategic plan?
Which move supports that best?
What is the opponent doing?
Which move would best counter what they are doing?
If your intuition says one thing then do that until you see why it was not as good as an alternative.
If you are not at least IM if not GM level it really wont make any difference to the outcome of your games.
How often does this happen?
How many people let you play the najdorf at all?
In the grand scheme of things how often does this come up in your games and is that enough to obsess about such a minor choice?


Chess software that can show all legal moves? I'm a casual player, and I learned chess from my Dad when I was a kid, but I still have the problem that I miss really obvious moves I can make (or I don't see really obvious moves the other side can make.)

Is there a chess GUI out there that has a feature that shows all the legal moves possible on the board at a time? Like as arrows pointing from the pieces to squares or something like that?

I believe most sophisticated GUI would have the feature to:

highlight possible moves for any piece; i.e. if you click (or hover) on a piece it will highlight all possible destination squares
highlight attacked pieces
highlight the last move

Arena and chesspad and many others should be able to do this.

Showing all possible moves is not useful as there are far too many in most positions, that you would not see anything anyway.

If you want to play online, also the lichess client (and probably others) can highlight moves.

Try chesspad. It is small and can highlight the available squares for a piece. Another alternative is Arena.


How should I have decided which side to attack on? I played black and was a pawn up. My plan was to castle on the opposite side from white's king, then use my majority on that side to pawn storm him. So on the turn shown below, I was about to castle long.

After we drew, I analysed the game with an engine, which preferred castling short and pushing the a-pawn, so it seems I should have done the exact opposite of my plan.

My question is, how should I have decided on which side to attack in this position? Why was my choice wrong?

Thanks in advance.

[FEN "r3k2r/1bp2ppp/pp2p3/8/8/2qPBP1P/P1P1Q1P1/R4RK1 b kq - 1 16"]

1. e4 e6
2. e5 d5
3. exd6 Bxd6
4. Nf3 Nf6
5. Bd3 b6
6. Bb5+ Nbd7
7. Nc3 Bb7
8. d3 a6
9. Bxd7+ Qxd7
10. O-O Ng4
11. h3 Ne5
12. Nxe5 Bxe5
13. Qe2 Qc6
14. f3 Bxc3
15. bxc3 Qxc3
16. Be3 O-O-O
17. Bd2 Qb4
18. Be3 Qc3
19. Qd2 Qxd2
20. Bxd2 Bc6
21. Bc3 f6
22. Rad1 Ba4
23. Rd2 e5
24. Rc1 g5
25. d4 exd4
26. Rxd4 Rxd4
27. Bxd4 Rf8
28. c3 c5
29. Bf2 Re8
30. Re1 Kc7
31. Bg3+ Kb7
32. Rxe8 Bxe8
33. Bd6 f5
34. g4 fxg4
35. hxg4 h5
36. Be7 hxg4
37. fxg4 Bd7
38. Bxg5 Bxg4
39. Kf2 Kc6
40. Ke1 Be6
41. a3 Kb5
42. Bd8 Ka5
43. Kd2 Ka4
44. Bxb6 c4
45. Bc5

You should castle "short" (on the king side). because you want to attack on the queen side without exposing your king.

1) White is short a pawn because of his missing b pawn. If you castle "long" and put your king on that side, White's open b file (and the black diagonal to b6) become compensation. If you don't, he's just a pawn down.

2) Your queen is powerfully placed on the queen side. You want to move up your pawns to support your queen, without exposing your king, or allowing your queen to be "pinned" by a rook. White has his queen on the king side and you don't, so it doesn't make sense to attack there.

3) Your best chances of getting an "outside" passed pawn are on the a and b files, so you want to advance those pawns, with your c pawn in support.

I had a similar (but not the same) question here.

Castling queenside would allow your four pawns and both rooks to push the opposing  king, with support from the light square bishop. This would allow you to pose a big threat on the king, protected only by two pawns and a bishop facing four pawns, two rooks, and possibly a bishop. The white rooks and queen would be somewhat blocked from joining the action due to the white pawn structure, reducing white's chances of defending their king.

Castling kingside would allow you to push all of your pieces on the flank. Your queen is already there, and the three pawns, bishop, and rook could quickly launch an attack from the B and C files. The isolated pawn on A2 can possibly be taken, leaving white with 2 pawns against 3 on the queenside. Support from your major pieces and the bishop would create a solid attack, and trading would be an even greater disadvantage for white after A2 is taken.

Either way, it is technically possible to overcome white. It is unlikely that a human would be able to forsee the outcomes which the computer sees, and I cannot give an exact reason for why it would prefer short castling.

My suggestion is that perhaps it would be better to castle kingside, because then you would have all of your pieces coordinated in one attack. Queenside castling would leave the bishop and queen slightly excluded due to white's pawn structure, reducing their effectiveness in a pawn attack on the white king.


How to work out quiet positions? I am a good player when I have a plan. If I have a certain goal in mind, I can see the way to it. But in quiet, planless, positions, I have difficulty as an attacking and tactical player. What is the best way to cope with them.

When there is no concrete plan of action possible, the general plan should be to -

  Improve the position of your pieces
  Trade off bad pieces if possible
  Try to create weaknesses in your opponent's position
  Keep your king safe and see if the enemy's king position can be compromised.

You could develop an opening repertoire that prevents quiet games. for example, play e4 as white, e5 or c5 as black. Against d4, play f5(dutch). This will considerably reduce "quiet" games.


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

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

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

I assume the last move was b2-b4.  The idea is 1...Bxb4 2.Rfb1 threatening to trap the queen with axb4.  So Bishop somewhere (2...Be7).  Now can we trap that queen or something? 3.Rb5 queen a6 is only open square which allows Rook discovery...but I don't see a win here. hmmm, 4.Rc5 Qb7 (4...b5!?) 5.Rc7 Qb8 6.Bg3!?

  Okay this line is total junk as pointed out in comments and the answer
  is far simpler.  Black has problems with the unprotected Rook on a8
  and it can't find a home on b8 because Bg3.


What are the minimum required pieces for checkmate in 3d chess? Assuming the rules of millennium 3d chess, what are the minimum required pieces for checkmate?

I realize this is an extremely difficult question, but in regular (2-dimensional) chess, we have rules of thumb for when two players should draw during the endgame.

A few examples of these kinds of scenarios (in 3d chess) would be much appreciated.

The following are minimum involving various pieces:

King + Queen
King + Rook + Any Piece
King + 2 Bishop
King + 2 Knight

This is only the theoretical minimum to actually mate. Whether or not it is possible to force a mate in this situation is a different question. You can see these mates by placing both kings in a corner, one on board 1, and the other on board 3.

Here is the following pieces you can do checkmate with:

King + Queen
King + Rook
King + 2 Bishops
King + 2 Knights
King + Knight + Bishop


How many unique pawn structures are possible? In an effort to classify chess games, I thought it would be useful to identify a set of positions by their unique pawn structure that would form a family of positions. There are indeed many positions but my rough calculations indicate 10^12 to be a upper limit of all possible combinations (I may be very wrong as I don't trust my calculations). But interestingly, it is way lower than the number of sensible position,s i.e. ~10^46. I am very interested to know the actual number of pawn structures (mwithout promotion). I guess actual number of legal positions would be difficult to estimate but a general idea might be good.

To classify pawn formations, a good source is chess master books that explore that topic. The book by Boris Persits comes to mind, for example.
I add that it seems impractical as you have been told, to make an exhaustive index of all the combinations that pawn chains can take.
However, it is useful to connect families of openings (classified by ECO, or by open / closed / flank, positional or tactical) and also by the types of endings that can be found according to the pawn structure.
This information has didactic utility for chess plans. There are books that touch on the subject of pawn structures and chess plans.
The pawn chain structures could be described with the characteristics: doubled or solitary / past / advanced / delayed / blocked pawns, V chain or inverted V chain, castling with / without fiancheto and other descriptors that I cannot imagine.
In this way, the number of pawn formations is much less than combinatorial theory can estimate.

For unique pawn structures I would not recommend going by any formula where you will have 10 to the power of n or any indices calculation. The best way to understand pawn structures is to know multiple openings in. There are more than 2000+ opening variations where the middlegame differs in many aspects along with the piece placement. It is always good to understand the patterns of the pawn structures by playing the openings and learning the middlegame.
This way, you can prepare some of the openings and understand the pawn structures which suit your style. This way, GMs prepare themselves. No one has a direct number of exactly how many pawn structures there are. Not even Kasparov or Carlsen might be interested in that unless you are able to show the perfect differences between each kind of pawn structure.


Will quantum computers solve chess? The theory is that there are more that 10^40 positions, and a computer that works with an atomic scale has to be impossibly large(As in galaxy-scale large), and well beyond our current level of knowledge.

But now, quantum computers will soon be available. This computer can have 2^n, instead of n bytes of space, because of quantum states. With this new large place for tablebases, will chess  be solved? Of course, this will take more breakthroughs in the future, but will we see 8 piece databases in the following years?

Many questions on the possibility of solving chess revolve on the fact that we don't have enough computer space to fill them. Will quantum computers change the status quo?

I'm not an expert on quantum computation but my understanding is that quantum computers are not expected to be useful for chess.

Quantum algorithms are very good at finding needles in haystacks: the three big quantum algorithms are Shor's factorization algorithm, Grover's database lookup algorithm and the Deutsch–Jozsa algorithm, which essentially determines whether a long list of numbers is either all zeroes, all ones or half of each.
All of these problems can be seen as examples of "I've hidden something: you must find it quickly." In factorization, I've "hidden" the prime factors and you must find them; in database lookup, I've hidden an entry with a given key in a large unsorted table and you must find it; in the problem solved by Deutsch–Jozsa, I might have placed a large number of zeroes in a table of ones but, with a classical algorithm, when you've looked at half the table and seen only ones, you might have just been unlucky and looked at the "wrong" half.  Note also that all of these problems could be solved quickly by an unrealistically parallel classical computer: you could try all the factors in parallel, look at all the database entries in parallel and look at all the values in the zero-one table in parallel.

Solving chess isn't even slightly like any of these problems. It's a fundamentally sequential activity. Whether or not my move is any good depends on what you do in response. Whether or not your response is any good depends on what I do in response to that. And so on.  You might imagine you can do the first ply of the search by taking a superposition of the possible moves.  But then what do you do at the second ply? You can't just take the superposition of all the positions we could be in after two ply because that has forgotten the tree structure. For example, consider this very artificial position, with white to move:

[FEN "1k6/ppp5/5Q2/7q/8/8/PPP5/1K6 w - - 0 2"]

If we forget the tree structure, Black is very happy. He says, "In two ply, the best position I can be in is that I deliver checkmate!"  This is true but, of course, White will never allow that, since White's best move is one that prevents Black from checkmating (or doing anything else).  Chess isn't about figuring out the best move you can possibly make in N ply: it's about figuring out the best move that your opponent will allow you to play in N ply. Quantum computers don't seem to be good at this back-and-forth, give-and-take reasoning. We don't even know how to solve chess with an unrealistically parallel classical computer.

Fair warning: This answer contains speculative numbers, and may be off by orders of magnitude.
It's just possible, but unlikely.
The issue isn't necessarily with whether or not quantum computers will be able to "parallelize" to that extent. The problem is one of simple physics, one that even quantum computers can't realistically get around. Put simply, there's a limited number of calculations that can ever be performed. This was answered by Thomas Pornin at Security.SE, and I quote some of his answer here:

Let's look at a more mundane perspective. It seems fair to assume that, with existing technology, each elementary operation must somehow imply the switching of at least one logic gate. The switching power of a single CMOS gate is about C*V2 where C is the gate load capacitance, and V is the voltage at which the gate operates. As of 2011, a very high-end gate will be able to run with a voltage of 0.5 V and a load capacitance of a few femtofarads ("femto" meaning "10-15"). This leads to a minimal energy consumption per operation of no less than, say, 10-15 J. The current total world energy consumption is around 500 EJ (5*1020 J) per year (or so says this article). Assuming that the total energy production of the Earth is diverted to a single computation for ten years, we get a limit of 5*1036, which is close to 2122.
Then you have to take into account technological advances. Given the current trend on ecological concerns and the peak oil, the total energy production should not increase much in the years to come (say no more than a factor of 2 until year 2040 -- already an ecologist's nightmare). On the other hand, there is technological progress in the design of integrated circuits. Moore's law states that you can fit twice as many transistors on a given chip surface every two years. A very optimistic view is that this doubling of the number of transistor can be done at constant energy consumption, which would translate to halving the energy cost of an elementary operation every two years. This would lead to a grand total of 2138 in year 2040 -- and this is for a single ten-year-long computation which mobilizes all the resources of the entire planet.

That is the absolute maximum number of elementary operations that can possibly be done. Now let's look at how many chess positions there are...

Let's do some quick numbers. Each of the 64 squares can be empty or hold one of 12 different pieces (R, K, B, Q, K, and P in black and white), so the total number of positions that you could set is at most
1364 = 196053476430761073330659760423566015424403280004115787589590963842248961.
That is about 2 x 1071 different positions. Of course this is a huge overestimate, because most positions are fake (we should eliminate positions with three or more kings, nine or more white pawns, pawns in the eighth rank, quadruple checks, etc). Let's take the square root:
1332 = 442779263776840698304313192148785281,
or about 5 x 1035. By taking the square root we are pretending that for each legal position there is a chess Universe worth of distinct fake positions. This is probably an underestimate, so the true answer must be somewhere in between these two numbers. Now we can confidently say that computers cannot study every legal position in a reasonable time. Even the "tiny" 1332 is too large...

That smallest number ends up being somewhere around 2120 or so.
Let's assume that we represent our boards with a 64-byte string. (Practically it would be handled a little differently, but let's go with it for now.) If I'm remembering my math correctly, a quantum computer would be able to represent this with an 8-byte string, or 64 bits. This leaves us with a total of 2126 to 2130 elementary operations just to store each legal and possible position.
Look at that for a moment. We're not doing anything useful with the information, we're just storing it. And to do so we are mobilizing the resources of the entire planet. Never mind where the storage is physically located. Ignore the whole issue of cooling. Set aside the issue of data transmission. We are diverting enough power to illuminate the Moon just to store the positions.
At the most optimistic of expectations, a quantum computer might be able to solve chess, at the cost of the entire planet's resources. Realistically, that will not happen.


As Black, what is the fastest way to beat Gnu Chess on easy mode? This is more of a puzzle. As far as I can ascertain, Gnu-Chess on easy mode always plays the same movesm What is the least amount of moves required to beat Gnu Chess on easy mode? Just to clarify, you are playing as Black, Gnu Chess is playing as White.

here how I win against gnu chess version 6.2.2 as black:

Nf3  d5
d4  Nf6
c4  e6
Nc3 c6
e3  Nbd7
Bd3  dxc4
Bxc4 b5
Bd3  a6
O-O  Bb7
e4 Qc7
dxe6  fxe6
Bc2 c4
Ng5  Nc5
Qf3  Bd6
Qh3  O-O-O
Re1  Kb8
Nf3  e5
Bg5  Nd3
Bxd3  Rxd3
Qh4  bxa4
Nxa4  Bb4
Bxf6  Bxe1
Rxe1  gxf6
Qxf6  Re8
Nc3  Rd6
Qg5  Rg6
Qe3  Rd8
Nd5  Bxd5
exd5  Rb6
d6  Rbxd6
Nxe5  Rd5
h3  Qc5
Qc3  Qd4
Nxc4  Qxc3
bxc3  Rd1
Kf1 Rxe1+
Kxe1  Rd3
Nb6+  Kb7
Na4  Rd8
c4  Rd4
Nb2 Kc5
f4  Rd8
Ke4 Rb8
Nd3+  Kxc4
f5
{White resigns} 0-1


What is the worst opening move in Chess960 for White? Is there a first move for white in Chess960 in which white can immediately blunder a piece or lose a significant advantage (say -2.0 or so)?

This calls for some scripting, so here's my first hasty attempt at it ;)

Here's a quick way you can do the search on your own in python, using stockfish 10 and only the python-chess package. All open-source and free-software!

Briefly, what the script will do:

Consider all 960 positions, one at a time
For each position, it scans over all legal white moves
For each move, it evaluates the position with a engine ponder time given by user (e.g. 1 second)
If the evaluation is below the given threshold (e.g. -2.0) then it shows the board, the FEN, the move and the evaluation.
At the end everything will be saved in a text file, so you don't need to log the printouts in the terminal.

Examples found running the script for first 5 chess960 positions

Let's showcase it for the first 5 chess960 positions where:

The evaluation threshold is set to -1.0
The ponder time is 1.0 second per move.

Here are the found cases: (below is the saved results in a textfile, first column is the chess960 position FEN, 2nd column the move whose evaluation fell below the threshold, and the 3rd column is the corresponding evaluation)

bbqnnrkr/pppppppp/8/8/8/8/PPPPPPPP/BBQNNRKR w KQkq - 0 1    g4  -2.19
bqnbnrkr/pppppppp/8/8/8/8/PPPPPPPP/BQNBNRKR w KQkq - 0 1    g4  -1.51
bqnnrbkr/pppppppp/8/8/8/8/PPPPPPPP/BQNNRBKR w KQkq - 0 1    g4  -1.66
qbbnnrkr/pppppppp/8/8/8/8/PPPPPPPP/QBBNNRKR w KQkq - 0 1    g4  -1.35

1.g4 seems to be commonly the worst move among the first 5 setups.

Not so surprising, since in all the so far considered chess960 positions, namely the first 5, the king stands on the usual kingside (specifically, on g1).

Thus, 1.g4 is a highly weakening move with the king on g1.

Here are the positions (updated, 3 more examples found by running script longer):

 eval = -2.19

 eval = -1.51

 eval = -1.66

 eval = -1.35

 eval = -2.8

 eval = -2.07

 eval = -2.12

Continue the search on your own using the script

To go over all 960 positions takes a lot of time and computational resources. So I leave it up to you and other if they are interested, to run the script for longer ponder times, to scan all 960 positions, and to play with the evaluation threshold of interest. To do that on your own, here's the python script, using Python 3.7.4, python-chess 0.30.1, and Stockfish 10 (place the engine file in same folder as the script):

import chess
import chess.engine
import os
import sys

arguments = sys.argv
pondertime = float(arguments[1])
evalthreshold = float(arguments[2])
#here we assume the engine file is in same folder as our python script
path = os.getcwd()
#Now make sure you give the correct location for your stockfish engine file
#...in the line that follows by correctly defining path
engine = chess.engine.SimpleEngine.popen_uci(path+'/'+'stockfish-10-64')

lsfens = []
lsmoves = []
lsevals = []

numberofpos = 960

for i in range(numberofpos):
    board = chess.Board.from_chess960_pos(i)
    print('Currently analysing the position below')
    print(board)
    print('--------')
    for el in board.legal_moves:
        info = engine.analyse(board, chess.engine.Limit(time=pondertime), root_moves=[el])
        t = str(info["score"])
        if t.startswith('#'):
                print(str(board.san(el))," eval = mate in ", t)
        else:
            if round(int(t)/100.,2)<evalthreshold:
                print('Starting 960 position index: ', board.chess960_pos())
                print('Position FEN: ',board.fen())
                print(str(board.san(el))," eval = ", round(int(t)/100.,2))
                lsfens.append(board.fen())
                lsmoves.append(str(board.san(el)))
                lsevals.append(str(round(int(t)/100.,2)))
    print('--------------------------------------')

engine.quit()

with open('FoundPositions_Pondertime_'+str(pondertime)+'_threshold_'+str(evalthreshold)+'.txt', 'w') as file:
    for i in range(len(lsfens)):
        file.write(lsfens[i]+'\t'+lsmoves[i]+'\t'+lsevals[i]+'\n')

How to run the script:

Copy paste the code into a textfile and save it with a name like 960evaluator.py
Make sure you have python3 installed, similarly for python-chess module (see here for installation) and have downloaded the stockfish binary for your OS.
Place the engine file and the script in the same folder, and open a terminal in that folder
Run the script with the command python 960evaluator.py 1.0 -2.0
Note the first argument you give after the script name is the ponder time per move in seconds. The higher the ponder time value, the more accurate the evaluation.
The second argument is the evaluation threshold: that is, all positions with 1st move evaluations below the given value (in this example -2.0) will be printed in terminal and saved at the end (you could do the saving while running so you can crash the script without losing the so far found cases).
Again, the found cases will be printed in terminal as they are found, but also saved in a text file placed in same folder as your script.

The terminal printouts will look like:

Currently analysing the position below
b b q n n r k r
p p p p p p p p
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
P P P P P P P P
B B Q N N R K R
--------
Starting 960 position index:  0
Position FEN:  bbqnnrkr/pppppppp/8/8/8/8/PPPPPPPP/BBQNNRKR w KQkq - 0 1
g4  eval =  -2.19

Have fun scanning, though do so with caution: running chess engines for long times on personal machines is bit risky as it quickly heats up!

NO.

The pawns are still in front of the pieces.
Only the piece placement has been changed.
No pawn move will be as bad as you asked.


Running down the opponent's clock on purpose Running out of time is a loss. Two players are both very low on time and quite far from a checkmate. What if one player makes some 'pointless' defensive moves to keep his clock running so that the other player, still trying to win, runs out of time.

I am new and I am asking because I have had opponents moving their king back around while I was there trying to do something and had no time left.

Is there some sort of rule that prevents my opponent from making useless moves while I try to win and run out of time?

That's how it goes. Time management is an important part of tournament chess play.

There is a rule called draw by insufficient material in FIDE, which prevents the situations you described.

It's draw automatically if any following situation happens:

King vs king
King vs king + knight
King + zero or more bishops vs king + zero or more bishops, where all bishops stands on same colored squares
Any combination of pieces in a position where stalemate is unavoidable.
Any combination of pieces in a position where checkmate is impossible.
Any combination of pieces in a position where it's inevitable to transpose to a position described above.

So you can't lose on time, in these kinds of positions.


Have we found every existing tactic? Is it possible that there are missing or unstudied tactics, waiting there to be found?

Maybe some of them have been played only by GMs and in so few times that they don't get to have a name on their own, maybe the rest of the world just see them as 'just another brilliant move'.

What I am saying is, if we were all geniuses and GMs, do you seriously think the number of known tactics would remain the same? Maybe they are so complex that they cannot be learned by books, but by experience.

Or, should I stop watching conspiracy movies?

The type of complex tactic you are thinking of is called a combination. A combination is a forcing series of moves to create some sort of advantage; some would also say that a combination must begin with a material sacrifice, but this is besides the main point. If you are interested in combinations, look at the games of Mikhail Tal, for one, who has been called "the wizard of combinations" for his daring, speculative sacrifices which often led to his opponent cracking under the pressure of searching out the one saving defensive resource; or Alekhine, "the genius of combinations", whose combinations, if not as daring as Tal's, were perhaps more sound.

Wikipedia gives the following example of a combination:

r1b2r2/p2p2kp/1pn1p3/8/1PP5/P2K1P2/2Q4P/R4B2 b - - 0 1

1... Rxf3+ 2. Ke4 (2. Ke2 Nd4+) (2. Kd2 Rf2+ 3. Be2 Rxe2+! Kxe2 Nd4+) d5+!! 3. cxd5 (3. Kxf3 Nd4+)  exd5+ 4. Kxd5 (4. Kxf3 Nd4+) Be6+ 5. Kd6 (5. Kxe6 Nd4+) (5. Kxc6 Rc8+) (5. Ke4 Bf5+) Rd8+ 6. Kc7 (6. Kxe6 Nd4+) (6. Kxc6 Rc8+) Rf7+ 7. Kxc6 Rc8+

In light of the impending disaster, White in fact resigned on move 3 (Move 22 in the actual game between G. Stepanov and Peter Romanovsky).

No, since Chess is not "solved", the resulting tactics are not solved.
There are just too many permutations and combinations..pun!!


Dynamic (not-drawish) response for black against the c3 Sicilian Basically what the title suggests. Many of the responses to the c3 sicilian (1.e4 c5 2.c3) that I find online result in very drawish positions usually with queens off the board and very little dynamic play. I want lots of action and craziness while still being sound.

This is currently my favored variation (but this is still quite drawish and doesn't feel very 'Sicilian-y'): 1.e4 c5 2.c3 d5 3.exd5 Qxd5 4.d4 Nf6 5.Nf3 Bg4 6.Be2 cxd4 7.cxd4 e6 8.Nc3 Qa5 9.O-O Nc6.

Here are variations that I've tried:

1.e4 c5 2.c3 d5 3.exd5 Qxd5 4.d4 cxd4 5.cxd4 Nc6 6.Nf3 Nf6 (this goes on to be kinda passive for black and mostly boring).
1.e4 c5 2.c3 Nf6 3.e5 Nd5, which almost is awesome except it becomes really drawish after 4.Bc4 Nb6 5.Bb3 Nc6 6.Nf3 g6 7.d4 cxd4 8.Bf4 Bg7 9.O-O O-O 10.Re1 d5 11.exd6 exd6 12.Bg5 Bf6 13.Bxf6 Qxf6 14.Nxd4 d5 15.Na3 Nxd4 16.Qxd4 Qxd4 17.cxd4 Bd7 18.Nc2 Bc6.

  Any ideas?

[fen ""]

1.e4 c5 2.c3 d5 (2...Nf6 3.e5 Nd5 4.Bc4 Nb6 5.Bb3 Nc6 6.Nf3 g6 7.d4 cxd4 8.Bf4 Bg7 9.O-O O-O 10.Re1 d5 11.exd6 exd6 12.Bg5 Bf6 13.Bxf6 Qxf6 14.Nxd4 d5 15.Na3 Nxd4 16.Qxd4 Qxd4 17.cxd4 Bd7 18.Nc2 Bc6) 3.exd5 Qxd5 4.d4 Nf6 (4...cxd4 5.cxd4 Nc6 6.Nf3 Nf6) 5.Nf3 Bg4 6.Be2 cxd4 7.cxd4 e6 8.Nc3 Qa5 9.O-O Nc6

The line with Nf6 is actually pretty interesting. I think you overlooked the main line which is 6...c4, not 6...g6. For the record, the delayed d4 is the less popular variation. It leads to unbalanced play:

[fen ""]
1. e4 c5 2. c3 Nf6 3. e5 Nd5 4. Bc4 Nb6 5. Bb3 Nc6 6. Nf3 c4 7. Bc2 Qc7 8. Qe2 g5 9. e6 dxe6 10. Nxg5 Qe5 11. d4 cxd3 12. Bxd3 Qxe2+ 13. Bxe2 h6 14. Ne4 e5

There are of course other sidelines in this variation, with a major alternative being 9. h3 for white, but I encourage you to look into it some more.

4fter After e4 c5 d4 cxd c3 d5 exd5 Qxd5 cxd4 e5 White can Simply play Nc3 and has a Little advantage After Qxd4 Dxd4 Nb5 Na6


Are there statistics on the results of armageddon games at the GM level? I've tried finding statistics on the results of competitive armageddon games played at a high level (say, GM level), but to no avail. Evidently, these statistics must exist, as for example FIDE changed the time controls in the official rules from 6 minutes-5 minutes to 5 minutes-4 minutes in preparation for the Carlsen-Karjakin WC match (thus indicating that they felt that 6-5 gave black too much of an advantage compared to 5-4).

Basically, does white really have a ~50% win rate in GM-level armageddon chess games?

The earliest Armageddon games I can find go back to the Women's World Chess Championship 2001, and the FIDE World Championship in 2002, which GM Ruslan Ponomariov won. This is probably a fairly complete list since Armageddon really only lends itself to knock-out tournaments or matches, and the question did ask primarily about GMs and Armageddon. There might be the occasional country championship that goes to tiebreaker, which I did not find, similar to when GM Irina Krush lost to IM Anna Zatonskih in 2008 for the U.S. Women’s Championship in a controversial finish.

So, while these stats may not be 100% complete, they can give a good idea about the overall statistics.

I am amazed by the results of this: Out of the 48 games I found, 24 were 1-0, 15 were 0-1, and 9 were ½-½. If you look at that both the 0-1 and ½-½ count as wins for black, then the result was exactly 24-24. Seemingly quiet a fair tiebreaker system.

Here is the data I used to compile this estimate.

FIDE World Chess Championship 2002

This was the only FIDE World Championship to use Armageddon during the period of when Kasparov broke off with the title until it was unified in 2006. Prior to this, in 1998 and 2000, they continued playing additional blitz games, and in 2005, FIDE reverted to a double-round-robin tournament.

GM Zoltan Gyimesi defeated GM Stuart Conquest 4-3 in round one. Gyimesi had white 1-0.
GM Emil Sutovsky defeated GM Alonso Zapata 4-3 in round one. Sutovsky had white 1-0.
GM Lazaro Bruzon defeated GM Liviu-Dieter Nisipeanu 4-3 in round one. Bruzon had white 1-0.
GM Jaan Ehlvest defeated GM Ilia Smirin 4-3 in round three. Ehlvest had white 1-0.
GM Alexey Shirov defeated GM Veselin Topalov 4-3 in round four. Shirov had black 0-1.

Chess World Cup 2005

GM Yuri Shulman defeated GM Vadim Zvjaginsev 3.5-3.5 in round one. Shulman had black ½-½.
GM Predrag Nikolić defeated GM David Navara 3.5-3.5 in round one. Nikolić had black ½-½.
GM Sergey Erenburg defeated GM Zviad Izoria 4-3 in round one. Erenburg had black 0-1.
GM Evgeniy Najer defeated GM Shakhriyar Mamedyarov 4-3 in round two. Najer had white 1-0.
GM Yuri Shulman defeated GM Vadim Zvjaginsev 3.5-3.5 in round two. Shulman had black ½-½.
GM Sergei Tiviakov defeated GM Oleg Korneev 4-3 in round two. Tiviakov had white 1-0.
GM Loek van Wely defeated GM Alexander Moiseenko 4-3 in round two. van Wely had white 1-0.

Chess World Cup 2007

GM Michael Roiz defeated GM Varuzhan Akobian 4-3 in round one. Roiz had white 1-0.
GM Konstantin Sakaev defeated GM Nikita Vitiugov 4-3 in round one. Sakaev had black 0-1.
GM Zhou Jianchao defeated GM Andrei Volokitin 4-3 in round two. Zhou had white 1-0.
GM Kiril Georgiev defeated GM Rustam Kasimdzhanov 4-3 in round two. Georgiev had white 1-0.

Chess World Cup 2009

This year, by some accounts a mistake, the tiebreaker was changed to four rapid games, then up to five pairs of blitz games, and only then, Armageddon. Not surprising, but there were no Armageddon games, however, GM Varuzhan Akobian did defeat GM Pavel Tregubov 9-7, just one game short of Armageddon.

Chess World Cup 2011

Starting this year, they went back to the previous tiebreak format, but with two shorter 10+10 rapid games added after the 25+10 rapids.
GM Yuri Drozdovskij defeated GM Alexander Motylev 5-4 in round one. Drozdovskij had white 1-0.
GM Leinier Domínguez Perez defeated GM Igor Lysyj 5-4 in round three. Domínguez Perez had white 1-0.

Chess World Cup 2013

GM Evgeny Tomashevsky defeated GM Alejandro Ramírez 5-4 in round one. Tomashevsky had white 1-0.
GM Julio Granda defeated GM Hrant Melkumyan 5-4 in round one. Granda had black 0-1.
GM Daniil Dubov defeated GM Ruslan Ponomariov 5-4 in round two. Dubov had white 1-0.

Chess World Cup 2015

GM Gabriel Sargissian defeated GM Mateusz Bartel 4.5-4.5 in round one. Sargissian had black ½-½.
GM Michael Adams defeated GM Viktor Láznička 5-4 in round two. Adams had white 1-0.
GM Hikaru Nakamura defeated GM Ian Nepomniachtchi 5-4 in round three. Nakamura had black 0-1.

Chess World Cup 2017

GM Levon Aronian defeated GM Maxime Vachier-Lagrave 5-4 in the semi-finals. Aronian had white 1-0.

Chess World Cup 2019

GM Anish Giri defeated GM Evgeniy Najer 5-4 in round two. Giri had black 0-1.
GM Yu Yangyi defeated GM Nikita Vitiugov 5-4 in the quarter-finals. Yu had white 1-0.

Women's World Chess Championship 2001

Note: I could not confirm the format with 100% accuracy. I am reasonably guessing that this used the same format as the men, and the women in 2008, which I could confirm. In addition, the brackets had the 4-3 results as in the men’s tournaments.

GM Zhu Chen defeated GM Maia Chiburdanidze 4-3 in the semi-finals. (no data)

Women's World Chess Championship 2004

GM Peng Zhaoqin defeated IM Joanna Dworakowska 4-3 in round one. Pend had black 0-1.
WGM Ketino Kachiani defeated WGM Nguyễn Thị Thanh An 3.5-3.5 in round one, Ketino Kachiani had black ½-½.
IM Tatjana Vasilevich defeated WGM Xu Yuanyuan 4-3 in round one. Vasilevich had black 0-1.
IM Lilit Mkrtchian defeated then WGM Monika Soćko 4-3 in round one. Mkrtchian had white 1-0.
Then WGM Kateryna Lagno defeated then untitled Ekaterina Atalik 4-3 in round two. Lagno had black 0-1.

Women's World Chess Championship 2006

None.

Women's World Chess Championship 2008

IM Elisabeth Pähtz defeated WGM Ilaha Kadimova 4-3 in round one. Pähtz had white 1-0.
GM Monika Soćko defeated WGM Sabina-Francesca Foisor 4-3 in round one. Soćko had white 1-0.

Women's World Chess Championship 2010

Then IM Harika Dronavalli defeated then IM Mariya Muzychuk 4-3 in round three. Harika had black 0-1 (on time in a lost position!).

Women's World Chess Championship 2012

This was the first year of the extended tiebreaker with the rapid 10+10 games added.
Then IM Mariya Muzychuk defeated WGM Cristina Adela Foișor 4.5-4.5. Muzychuk had black ½-½.

Women's World Chess Championship 2015

GM Tatiana Kosintseva defeated WGM Mary Ann Gomes 5-4 in round one. Kosintseva had black 0-1.
Then WGM Aleksandra Goryachkina defeated IM Lilit Mkrtchian 5-4 in round one. Goryachkina had white 1-0.

Women's World Chess Championship 2017

IM Anastasia Bodnaruk defeated WGM Mitra Hejazipour 5-4 in round one. Bodnaruk had white 1-0.
GM Tan Zhongyi defeated GM Anna Ushenina 4.5-4.5 in round two. Zhongyi had black ½-½.
IM Nino Khurtsidze defeated then IM Nino Batsiashvili 5-4 in round two. Khurtsidze had black 0-1.
GM Tan Zhongyi defeated GM Harika Dronavalli 5-4 in the semi-finals. Tan had black 0-1.

Women's World Chess Championship 2018

GM Kateryna Lagno defeated WGM Natalia Pogonina 5-4 in round three. Lagno had white 1-0.

US Women’s Championship 2008

Then IM Anna Zatonskih defeated IM Irina Krush 3-2. Zatonskih was black, and white flagged, 0-1.

https://en.chessbase.com/post/us-women-s-armageddon-reactions-from-our-readers

World Chess Armageddon Series 2019

Nepomniachtchi -Karjakin 0-1
Radjabov-Karjakin ½-½
Radjabov-Dubov 1-0
Radjabov-Kramnik ½-½

https://www.chessbomb.com/arena/2019-world-chess-armageddon-series

The answer is no, as theere is data.  But it has not even been aggregated.
Nobody is known to have done meaningful statistics on that data.
Armageddon is somewhat arbitrary as it tries to balance the effect of time versus the probability that black could draw or win so as to have a definitive play off winner instead of a long long string of drawn games.
But it is still a stretch to say that it truly represents the 'winner' of a tournament or a match at a much longer time control.


Hardware used in AlphaZero vs Stockfish match I understand that AlphaZero has to use a different kind of hardware than regular Stockfish. I would expect that the hardware has a large effect on engine strength. That's why I wonder whether there have been any attempts made to provide comparable hardware to both. Also what would "comparable" mean here?

Specifically I read that people complain about:

Stockfish being given only 1 GB of cache, and
the time limit of 1 min/move (How would this disadvantage Stockfish?)

That's why I wonder whether there have been any attempts made to
  provide comparable hardware to both.

This is Google you're talking about! So the answer is obviously "No".

From the original paper hardware used for initialising and training -

  Training proceeded for 700,000 steps (mini-batches of size 4,096)
  starting from randomly initialised parameters, using 5,000
  first-generation TPUs (15) to generate self-play games and 64
  second-generation TPUs to train the neural networks

and hardware used for the games -

  AlphaZero and the previous AlphaGo Zero used a single machine with 4
  TPUs Stockfish and Elmo played at their strongest skill level using 64
  threads and a hash size of 1GB.

So, AlphaZero used special hardware developed by Google. It used specialized Tensor Processor Units (TPUs) rather than general Central Processing Units (CPUs) as are available commercially.

This is how Wikipedia describes the second generation TPUs they used -

  The second generation TPU was announced in May 2017. Google stated the
  first generation TPU design was memory bandwidth limited, and using 16
  GB of High Bandwidth Memory in the second generation design increased
  bandwidth to 600 GB/s and performance to 45 TFLOPS. The TPUs are then
  arranged into 4-chip 180 TFLOPS modules

They used 4 TPUs for the games, so a processing power of 180 TFLOPS.
Note TFLOPS = 1000 billion floating point operations per second.

For comparison Intel's latest most powerful chip is the Core i9 Extreme Edition processor which clocks in at 1 TFLOP. A top of the line I7 that you would find in a gaming machine would typically be about 100 GFLOPs (i.e. one tenth of a TFLOP).

I think it's fair to say that AlphaZero was using an 800 pound gorilla of a hardware configuration compared to Stockfishes mouse.

First paragraph more detail, second short and simple answer third paragraph my opinions on the situation

With AlphaZero the hardware has 0 effect on the strength of its play. It may take longer but not because it’s thinking. It’s a neural network, which means you feed it info in a vector (a single column table) it does simple math thru a giant tensor (a 3 or more dimensional table) then it spits out the answer.
Stockfish needs time to be good because it checks possible positions to see if a move is beneficial, so the longer it looks at the problem the more position/moves it can check.

There isn’t really a comparable hardware setup. Because they have different needs, Stockfish needs to analyze more positions while AlphaZero just needs to make a move. And people are upset because AlphaZero's computer is technically much more powerful and they think they should be equal in that regard. But, AlphaZero doesn’t need that supercomputer after training.

In my opinion it doesn’t matter what they give to either side, unless Stockfish has an unreasonable amount of time it will probably tie a few more games but in general a similar effect will happen. This is why I think this, Stockfish initially evaluates with pieces and their values while, Alpha played (probably) millions of games to realize what is important strategically. Which is why Alpha sacs a lot more than Stockfish would ever, but gains huge positional advantages.


King or Queen-Which piece is which? I recently bought a set of wooden chess pieces, which I liked for its simplicity.

I'm not sure, however, which one is supposed to be the king and which one is supposed to be the queen.

I would say that the one with the spike is the queen, and the one more flat is the king. Am I right, or is it the opposite?

In general, a chess set has the king as the tallest piece, followed by queen, bishop, knight, rook and pawn in that order. Notice in the starting position how the piece height decreases smoothly from the centre to the edge. (Also, when buying a chess set, usually the height of the king is given as a guide to the size of the chessmen.)

Thus I would say the king is the taller of the two pieces, which from your picture looks to be the one with the spike on the left.

This ordering of height may not hold for particularly ornate decorative sets.

However, if you're not going to use the set to play against other people in tournaments (where usually Staunton pieces are mandated anyway), the correct answer would probably be: the king is whichever piece you think it is.

The king is the one on the right, because that is the shape I know a chess king has, just that the cross is left out, still it has the shape of a King,  therefore the right one is the king.


Worrying inconsistency in playing strength I recently found time to make a study plan and improve my playing strength. Using this plan, I was able to achieve a 1900 average rating on online chess sites.

Since a couple of days, I have in a certain sense "lost the feel" of the game, for seemingly no reason at all, and my playing strength quickly dropped to the 1600-1700 range. No matter how hard I try, I don't seem to regain those abilities I had mere weeks ago.

How do I get that "chess focus" back? Has anyone had this experience before?

Don't worry you're not alone in this, I can assure you almost all chess players/enthusiasts go through such periods, not only at the start, but throughout their whole chess experience. Of course there are many elements involved here, that at the end of the day define your performance, but let's stick to those that are most common for all: (bear in mind these points are purely speculative as I cannot possibly know what may be truly causing your performance drop without actually knowing you!)

Learning curve: Basically whatever new we learn and try to incorporate with our chess knowledge, be it new tactics, new positional ideas, more opening varieties, weird endgame situations, etc. there's some minimum necessary time involved (different for everyone of course) to be able to put these new ideas into practical usecases and actually make them work. Why? well one immediate reason is that everyhting in chess requires some amount of experience until it comes closer to being understood. Prime example is when we all first learnt about different checkmating ideas, and then wanted to immediately apply them in every game we played, and of course instead we just end up losing because by giving such strong importance just to some checkmating pattern we become completely ignorant to the more basic ideas underlying each position (activity, safety, structure etc.). So I think you most probably had an immediate boost to your rating (reaching 1900) more by blind chance than anything else.
What you should retain from my first bullet point is: stay positive (i.e. care more about your play than rating, it's just a number after all...) and keep playing your usual chess, and whatever new you learn along the way, as you keep playing you will get more and more appropriate chances to putting them into good use, meaning you should let the occasions present themselves first and then try applying what you've learnt. By no means you should take this statement as equivalent to "not controlling the evolution of the game", after all that's the whole point of positional play(keeping a grip on the position and imposing its evolution on your opponent to the extent that you can), my point only concerned specific precise new things that you may learn, e.g. rook endings, or known theoretical drawn configurations etc. In this way you will slow by slow incorporate everything new that you learn much more naturally. Simply put by playing more you will discover more about the applicability of the things you've learnt.
Now one orthogonal reason to the previous two would be: ratings are always fluctuating, specially on online servers (we most often just play for fun and mess around hence may end up losing a lot of points suddenly-also bearing in mind that they're usually short time control games->hard to keep a consistent rating), so I think everyone experiences this at any level, what is more important is your average rating, say in the last 2 months, that says a lot more about your performance. I myself have always had drops of roughly -+200 rating points every now and then, same goes for most of my friends and people I play against. Chess is really a lot about struggling, because of the extremely rich dynamics of the game, in every game there are so many things that are completely different and unknown compared to our previous experience.
Another point you brought up was "chess focus": One's mind may very well be completely at ease before sitting down and playing a game of chess, but may still lose his/her focus easily during the game if not careful. At any stage of the game, it is extremely crucial to stay completely alert of at least the most important elements of the position (no need for examples here really). But how? well apart from the fact that everyone has different ways of getting hooked into a game (concentrating), there are general ways of staying focused: e.g. whether it's your turn to play or not, you should be continuously calculating relevant lines to your postions, and absolutely avoid saying to yourself "I'll just wait and see what he/she plays then I'll think about my move", instead you should always assume that there are more things to the position at hand that you see at first sight, so the more you try to calculate different variations (within the time you have) regardless of whether they're working lines, you will nonetheless discover more about the space of possibilities hidden in the position, and always assume your opponent is going to play the best move you can think of. All of this, as part of your general attitude towards chess-playing, will to some extent improve your focusing abilities.
Enough with speculations :) My last advice: just keep up your playing routines and don't allow for big gaps of inactivity in your playing as much as you can, don't be ignorant towards your losses, instead dig into them as much as you can and you'll have a lot more concrete improvements resulting from that than anything else. Hope this has been helpful!

Fluctuation in results is more normal for lower rated players than experienced GMs.

1900 is rather in the middle of the range, and since that is online, it is slightly to the lower end.   Although you would be almost near the average of OTB players.

You need more practice and less playing especially blitz type games online.  Try playing at G10-15SD with no addons or delays.


Can Black save this Knight vs Bishop endgame with a pawn down? After playing horribly in the opening, my opponent played a couple of suboptimal moves which suddenly allowed me to exchange some pieces and get the following unclear position.

I thought about giving the h pawn away, giving White two potentially
useless h pawns if he captures gxh4. However, I thought that making
use of it would require trading my g pawn for the White f pawn, which
seems to be impossible.

[White "Villain (2200)"]
[Black "Hero (2000)"]
[fen "2B3k1/5pp1/4pn2/8/3P3p/4P1PP/5P1K/8 b - - 0 1"]

1... Ne4 2.Kg2 hxg3 3.fxg3 *

The position after fxg3 was when I needed to formulate a plan. I thought of several options, all of which are more or less passive defenses, as I think moving my pawns would only weaken them and gain nothing in any position.

First idea: Leave my king on g8, and sacrifice the knight to get a fortress.
More precisely, force White to move his pawn to g6 and trade the
knight and f7 and e6 pawns for White's other pawns  (king, pawn g6,
light-squared bishop vs. king g8, pawn g7).

[Event "Draw"]
[fen "6k1/6p1/3K2P1/8/4B3/8/8/8 b - - 0 1"]

However, I didn't see any
way to force this: if White can keep any pawn not in g6, he wins if I sacrifice the knight.

Second idea: Leave my king to protect the g pawn. This forces White to exchange
the e pawns. Then I can use my king to stop the passed d pawn and my
knight to stop the kingside pawns. However, from what I calculated (and analyzed afterwards), it seems it is not sufficient. This is just an example
of what I think could happen; I haven't checked every move thoroughly, but the general idea is still the same: Black can block
White's d pawn, but White can always force a win due to Black
knight's limited mobility and zugzwang.

[White "Villain (2200)"]
[Black "Hero (2000)"]
[fen "2B3k1/5pp1/4p3/8/3Pn3/4P1PP/6K1/8 b - - 0 3"]

3... Nd6 4.Ba6 Kf8 5.Bd3 Kg8 6.Kf3 Kf8 7.e4 Kg8 8.d5 exd5 ( 8...Kf8 9.e5 ) 9.exd5 Kf8 10.Ke3 Kg8 11.Kd4 Kf8 12.Kc5 Ke7 13.Kc6 g6 ( 13...f6 14.Kc7 Ne8+ 15.Kc6 ) 14.Kc7 Ne8+ 15.Kc6 f5 16.g4 fxg4 17.hxg4 g5 18.Bg6 Nf6 19.d6+ Kd8 20.Bf5 Ng8 21.Kd5 Nf6+ 22.Ke6 Nd7 23.Kf7 Ne5+ 24.Kf6 Nc4 25.d7 1-0

During the game I remembered that KBPvKN with the advanced pawn can be a win in some positions. However, I didn't remember when that happens, and I also couldn't see
any way to force the exchange of all kingside pawns before allowing White to advance his pawn this far. In post mortem, I was able to blitz a win against the opponent in a position similar to this (without the g pawns), even though he claimed it is an easy draw.

Third idea: Use my king to stop the d pawn, exchange my e pawn to White's d or e pawn and force him to defend the isolated pawn so he can't make progress. This is what I decided to do in the game, making by endgame skills look ridiculous.

[White "Villain (2200)"]
[Black "Hero (2000)"]
[fen "2B3k1/5pp1/4p3/8/3Pn3/4P1PP/6K1/8 b - - 0 3"]

3... Kf8 4.Ba6 Ke7 5.Bd3 Nf6 6.Kf3 Kd6 ( 6...e5 7.dxe5 Nd7 8.Kf4 Ke6 9.Bc4+ ) 7.Bc4 Nh7 8.h4 Nf6 9.g4 Nd7 10.g5 f6 11.Kg4 Nb6 12.Bb3 e5 13.gxf6 gxf6 14.h5 Ke7 15.h6 Kf8 16.Kf5 1-0

Something like 6...e5 was my idea but I couldn't make it work in any position. For example, after 6...Kd6 7.Bc4, I realized the f7 pawn would hang. I saw no other way to make my position any better: any pawn move would weaken them and any king move would give White more space. Only after 13.gxf6 I realized that my plan of moving king to stop the d pawn allowed White's king to break through easily.

Question: Did I miss something? Was one of these plans drawing after all, or is there a resource I didn't see, or is the game simply lost?

I think it is good to notice the possibility of different fortresses, like the one you mention, and of course the wrong coloured bishop for the h-pawn. But to turn reaching such a fortress into a "plan" is way to early in this position.

I think fxg3 was probably ok. At the first glance it looks ugly that now there are white prospects for a passer on the d-line and on the h-line, but your g and f-pawns can actually deal with the white g and h-pawns. Against g4 and h5 you should play f6 and against h4 and g5 (like in the game) you could have played g6. These setups prevent an h-passer.

But maybe 10.f6 was still ok. Then you certainly should have played 11…fg 12.Kg5 Nf8 which prevents the intrusion of the white king. But even here h5-e4-e5-h6 and Kf6 might just win for white.

An engine will be able to come up with better lines, but my feeling is that

Keeping your pawns compact.
Keeping the white king away.
Preventing a h-passer.

might have earned you a draw. (Coincidentally you violate all these guidelines with the move e5, after which you are surely completely lost.)

Against a human it could certainly happen.  Black should not resign!
But against a computer maybe,  my intuition say no.

More importantly is how good are white and black at endgames.  That could be worth more than a pawn.

I would play on as white and expect to win.  But I always expect to win endgames:)

I would play on as black and expect to draw.  But I am confident in my endgame play.


Does white have an advantage? It is often debated that white has an advantage over black. Some even say that with perfect play on both sides, black simply cannot win. Is there any research that backs up this claim, or is it mere speculation by the greats such as Rauzer?

Also, if this has been or could be proven true, could the black pieces be given some sort of aid to make them equal to the white ones?

These statistics come from a database of over 600,000 games:

White wins   37.35%
Black wins   27.41%
Drawn        35.23%

http://www.chessgames.com/chessstats.html

The stats suggest that White has a significant, measurable first-mover advantage. Not an overwhelming advantage, but better than the house advantage in any casino game.

Is that advantage structured into the game or psychological? Comparative stats on games between mature chess engines may help to decide that.

Though taking it from a suggested article, there is a great need to point it out literally as it is the best argument.

"The first-move advantage is founded more in psychology than in reality." - Andras Adorjan

Explanation of above conjecture:

First-move advantage doesn't just exist in Chess but approximately in all games but theoritically (pychologically). This is often neat. Come, play football! Let team A (say) start the game then, if, both teams A and B play perfect games (equal play), A is going to have first Goal. But this is certainly all theoretic. This has very small to do with Reality (as it happens nearly never) since, one team is always going to play different from other. This either results in a Draw (before penalty shootout) or a win/lose.

  The point is, "theoretically, things seem much different as they look practically". This is why the problem is a chess theorists' problem and not of chess players!


Is it possible for stockfish to tell that mate is in X moves, when mate is in X + Y moves? I know that it is possible for a chess engine to evaluate a position as mate in X moves, when in fact there exist a mate in smaller number of moves. But can the reverse situation happen?

For example the engine evaluated a position as mate in 8 moves, but actually the best possible mate is in 9 moves (or 10 or 13).

To be more concrete the engine is stockfish.

No, it isn't possible because, before Stockfish says it is Mate in 8, it views the position from the aspect of the losing side, i.e, the evaluation is the best that can be obtained by the losing side.

In other words, Mate in 8 is what happens if the losing side plays the possibly best defense. If the losing side plays sub-optimally, it could lose faster, but 8 moves is the longest possible postponement of Checkmate

I think it helps to realise that the engine does not make assumptions for mistakes during its calculation, instead it only considers best-play by both sides for as far as it can see (depth, time, etc). This would be the only objective way of going about it, and that's how it assigns its principal variation.

In general positions, the normal working of the engine is to continuously go through ever more lines to higher depth, and adapt accordingly its evaluation of the main variations. But, when it comes to there being mating sequences among the principal variation candidates, the key difference stems from the fact that all mating variations are by definition forcing sequences, i.e., the engine gives such variations a "mate in X" evaluation only after having exhausted the full set of possible replies (more technically, within the allowed depth, it has managed to reach the endpoints of all those branches, and they have ended in checkmates). Thus by construction, it cannot have mis-evaluated there being at least "a mate in X" when in fact there's only a mate in "X+Y>X." And as for cases where it keeps finding shorter mates, that's because it is still performing truncations in its exploration of the tree, so even though it may have already found one branch with a forcing mate-sequence (thus at least one winning move), the other unexplored branches (other potential winning moves) may have led to more efficient mates, given more analysis time it will eventually check them and realise a shorter mate.


Not Developing a Piece in the First Five Moves Here are the first few moves:

1.c4 e5 2.Nc3 Bb4 3.Nd5 Bc5 4.Nf3 e4 5.d4 Bf8

After the fifth move, black has essentially only pushed one pawn, while while has developed two knights and his c-pawn and d-pawn. However, the current position does not seem bad for black at all. 365chess.com gives winnings percentage White / Draw / Black as 25% /50% /25%.

[fen ""]
1.c4 e5 2.Nc3 Bb4 3.Nd5 Bc5 4.Nf3 e4 5.d4 Bf8

My question is, in the first few moves, has black violated any opening principles? Why this position is not too bad for black while he has only pushed one pawn while white has developed two nights (and it is white's turn now)?

Obviously black has violated principles such as:

don't move a piece twice
develop pieces

However opening principles are just general guidelines and in very concrete positions like the one at hand they are of little use. There are many established openings where opening principles are broken, so nothing wrong with that.

In the final position it is white's move, however the knight on f3 is attacked and has to move. After the knight has moved, black will most certainly kick away the other knight by playing c6 and then create a strong pawn center with d5 or f5.

White has currently a lead in development but black has more space and will have an easier development for its minor pieces than white. If there is nothing immediately threatening from white, I don't see why black should have a bad position.

Note that my engine still prefers white's position by about +0.5.

The first moves look, by Black and White like a "Sicilian with reversed colors!"
(Before Bb4)
For Black I would prefer Nf6 (rather than Bb4)

After Bb4, I would move Qc2, (rather than Nd5) then a3

1) In the opening The first plan is "sound development", prepare for a possible castling, as soon as possible.

2) A "premature attack", usually means a lose of time (tempo), which is dangerous in the opening phase!


How can one become a very good chess player without studying chess or openings? I heard that Capablanca never liked to bother with openings, would never study chess or read books. Despite all this, he became world champion. Is this an exception to the rule?  Have times changed today were players are too strong and study is mandatory?

Capablanca didn't like to "study chess or openings" means that he didn't like to study formal chess (as it was understood in his time).

On the other hand, he studied more, and had a better grasp of chess principles, particularly as they related to the middle and end game. His best exposition of this was "Chess Fundamentals."

Because he focused on principles, rather than "book" moves, he was the hardest person in the world to surprise with a new line. He beat back the Marshall Attack that Marshall had reserved especially for him.

Nowadays, there is more and better book knowledge, so it's helpful to learn some of it. And the other reason is that not many players have the instinctive grasp of the game that Capablanca had.

In those days, people do not have to reckon with tactics and preparation at the level of silicon beings, they just need to play better than the other guy. If Capablanca were still alive today, he would be crushed by most elite players because general principles do not stand up to tactical refutations, especially if they came from the computer.


Sicilian with 1.e4 c5 2.c3 d5 3.Nf3? I don't know much "Sicilian" theory, and decided to develop instead to defend e4. My opponent captured, and I got the pawn back with the obvious Qa4 check. Although he tried to start a queen hunt, she was never in real danger, but quite annoying for black. After finally pushing to d4 I had a fine play and managed to win. I couldn't find anything about this line, so I guess there must be serious drawbacks, and so I'd like to see a refutation.

[FEN ""]
1.e4 c5 2.c3 d5 3.Nf3 dxe4 4.Qa4+ Bd7 5. Qxe4 Bc6 6. Qf4

Black has a small advantage in your position, but it's certainly not unplayable for white.  Stockfish rates the position you've given around -0.2, which is pretty close to even.  If black plays well it seems difficult for white to get a good d4 break, though if black tries too hard to chase the queen perhaps white will be able to get back the advantage.  The main problem seems to be that the pawn on c3 is counterproductive: white can't play d4 with advantage and the pawn on c3 interferes with white's queenside development.

Stockfish suggests the following line, where black retains a small advantage (around -0.3)

[FEN ""]
1.e4 c5 2.c3 d5 3.Nf3 dxe4 4.Qa4+ Bd7 5. Qxe4 Bc6 6. Qf4 e6 7.Na3 Bd6 8.Qg4 Ne7 9.Nc4 O-O 10.Nxd6 Qxd6 11.Be2 e5 12.d3 Nd7 13.O-O Rfe8

Black is somewhat better off playing Nc6 on the 4th or 5th moves instead of occupying that square with the bishop.  White is still fine, but should avoid 4. ... Nc6 5. Qxe5 and instead play 5. Ne5.

[FEN ""]
1.e4 c5 2.c3 d5 3.Nf3 dxe4 4.Qa4+ Nc6 5.Ne5 (5.Qxe4 Nf6 6.Qc2 a6 7.d3 e5 8.Nbd2 Be7 9.Nc4 Qc7 10.Be2 O-O 11.O-O Nd5 ) Bd7 6.Nxd7 Qxd7 7.Qxe4 Nf6 8.Qf3 e6


Blindfold chess tournaments I was always interested to play blindfold chess not with a friend but versus a real opponent but I have heard only about such tournaments for elite players (like "Melody Amber"). Are there any blindfold chess tournaments, where players with Elo around 2000 points (standard) are allowed to participate?

Online:

Lichess and Internet Chess Club provide an online functionality to play blindfold chess and you can try to make a suggestion on their forums to organize a blindfold tournament.
This will probably be unofficial though and I do not now if that fills your expectations.

Local:

As @JossieCalderon said in his comment, you don't lose anything to make a suggestion in your local chess club about organizing a blindfold tournament.
You can even start by making an attempt through social media and see if enough people who want to participate appear.

Good luck :)

PS: Lichess blindfold team

Blind Chess Olympiad is the most important event for blind chess. there are several youtube videos where you can sneak out a bit.


Does the new Netflix series "The Queen's Gambit" resemble any real life chess master? Recently, a Netflix series has been launched entitled The Queen's Gambit which surely created a lot of hype in the chess community. Does the protagonist Beth Harmon resemble anyone (fully or partially) in real life? This is although the makers of the series said the character is fictional. Sill, I am kind of sceptic about this.

The character Beth Harmon is purely fictional. The series is based off a book by the same title by Walter Tevis. The author had a tendencie to base books drawing from personal experiences but he wasn't a chess prodigy that's for sure. He was however a good club level player which is why the book has such strong chess knowledge. In that time period, there are no valid players that could fit as inspiration for the character (that I can place at least). The chess advisors in the show were Bruce Pandolfini and Garry Kasparov which really shows the high-calibre efforts the production team went to to get the show's chess moments bang on.
EDIT: Found the following article
https://www.radiotimes.com/news/on-demand/2020-10-29/the-queens-gambit-book-netflix/

Tevis previously told The Times that the character was created as a
“tribute to brainy women” adding that “I like Beth for her bravery and
intelligence. In the past, many women have had to hide their brains,
but not today,” he said.
He listed his daughter and his aunt – who had gifted him with his first chess set – among the women who had inspired the character.

Regarding the games however that is a different story; Most the games are based on famous games.  The final game in the series where she beats Borgov is based off a game between Vassily Ivanchuk and Patrick Wolff at the Biel Interzonal in 1993 for example. An absolute monster of a game to watch though;
Those researching the film did a fantastic job in finding great games to base their games on. Specifically move 38 Ne6 which is a more direct and simplified line.
The Movie Game (Simplified Ivanchuk v Wolff)
The movie is a simplified and more modern line than the game it was based on.
[FEN ""]
[Event "?"]
[Site "?"]
[Date "2020.08.24"]
[Round "?"]
[White "Harmon"]
[Black "Borgov"]
[Result "1-0"]
[ECO "D20"]
[PlyCount "105"]
[SourceVersionDate "2020.10.31"]

1. d4 d5 2. c4 dxc4 3. e4 Nc6 4. Be3 Nf6 5. Nc3 e5 6. d5 Ne7 7. Bxc4 Ng6 8. f3 Bd6 9. Qd2 Bd7 10. Nge2 a6 11. Bb3 b5 12. a4 O-O 13. O-O Qe7 14. Rac1 Nh5 15. g3 h6 16. Bc2 Rab8 17. axb5 axb5 18. Ra1 Ra8 19. Bd3 Bb4 20. Rxa8 Rxa8 21. Qc2 Bc5 22. Nd1 Bd6 23. Nf2 Nhf4 24. Rc1 Qg5 25. Kh1 Qh5 26. Ng1 Nxd3 27. Nxd3 f5 28. Nc5 Bc8 29. Rf1 Ne7 30. Qd3 fxe4 31. fxe4 Qg6 32. Kg2 Kh7 33. Nf3 Ng8 34. Nh4 Qg4 35. Nf5 Nf6 36. h3 Qg6 37. Ne6 Ra4 38. b3 Rxe4 39. Nxd6 Bxe6 40. dxe6 cxd6 41. e7 d5 42. Bc5 Qe8 43. Qf3 Qc6 44. b4 Qe8 45. Qf5+ Kh8 46. Qxf6 gxf6 47. Rxf6 Qh5 48. Rf8+ Kg7 49. e8=Q Re2+ 50. Kf1 Qxh3+ 51. Kxe2 Qg2+ 52. Rf2 Qe4+ 53. Kd2 1-0

The Game that its based off
[FEN ""]
[Event "Biel Interzonal"]
[Site "Biel"]
[Date "1993.??.??"]
[Round "1"]
[White "Ivanchuk, Vassily"]
[Black "Wolff, Patrick G"]
[Result "1/2-1/2"]
[ECO "D20"]
[WhiteElo "2705"]
[BlackElo "2585"]
[PlyCount "144"]
[EventDate "1993.07.??"]
[EventType "swiss"]
[EventRounds "13"]

1. d4 d5 2. c4 dxc4 3. e4 Nc6 4. Be3 Nf6 5. Nc3 e5 6. d5 Ne7 7. Bxc4 Ng6 8. f3 Bd6 9. Qd2 Bd7 10. Nge2 a6 11. Bb3 b5 12. a4 O-O 13. O-O Qe7 14. Rac1 Nh5 15. g3 h6 16. Bc2 Rab8 17. axb5 axb5 18. Ra1 Ra8 19. Bd3 Bb4 20. Rxa8 Rxa8 21. Qc2 Bc5 22. Nd1 Bd6 23. Nf2 Nhf4 24. Rc1 Qg5 25. Kh1 Qh5 26. Ng1 Nxd3 27. Nxd3 f5 28. Nc5 Bc8 29. Rf1 Ne7 30. Qd3 fxe4 31. fxe4 Qg6 32. Kg2 Kh7 33. Nf3 Ng8 34. Nh4 Qg4 35. Nf5 Nf6 36. h3 Qg6 37. g4 Bxc5 38. Bxc5 Ra4 39. Rf3 Rc4 40. Be7 Bxf5 41. Rxf5 Rd4 42. Qe3 Rxe4 43. Qf3 Rf4 44. Rxf4 exf4 45. Bxf6 Qxf6 46. Qd3+ Qg6 47. Qe2 c6 48. Kf3 cxd5 49. Kxf4 Qf6+ 50. Kg3 Qd6+ 51. Kf3 b4 52. h4 Qf6+ 53. Kg3 Qd6+ 54. Kf3 Qf6+ 55. Kg3 g6 56. Qe8 Qd6+ 57. Kf3 Kg7 58. g5 hxg5 59. hxg5 d4 60. Qe4 d3 61. Qb7+ Kf8 62. Qc8+ Ke7 63. Qb7+ Ke6 64. Qe4+ Kd7 65. Qb7+ Kd8 66. Qa8+ Kc7 67. Qa7+ Kc8 68. Qa8+ Kc7 69. Qa7+ Kc6 70. Qa6+ Kc5 71. Qxd6+ Kxd6 72. Ke3 Ke5 1/2-1/2

I believe the Kentucky game to be based of Nezhmetdinov vs Kasparian game as well.
[FEN ""]
[Event "Spartak Team Ch (1955), Riga LAT"]
[Site "?"]
[Date "1955"]
[Round "?"]
[White "Rashid Gibiatovich Nezhmetdino"]
[Black "Genrikh Kasparian"]
[Result "*"]
[ECO "B11"]
[PlyCount "93"]

1. e4 c6 2. Nf3 d5 3. Nc3 Bg4 4. h3 Bxf3 5. Qxf3 e6 6. g3 g6 7. Bg2 Bg7 8. O-O Nd7 9. Qe2 d4 10. Nb1 e5 11. d3 Ne7 12. f4 Qc7 13. a4 O-O 14. f5 f6 15. Nd2 Bh6 16. Kh2 Kh8 17. fxg6 hxg6 18. Nf3 Bxc1 19. Raxc1 Nc5 20. c3 Nb3 21. Rcd1 Rad8 22. Nh4 Qc8 23. Bf3 Qe6 24. Bg4 Qf7 25. Nf3 Qg8 26. h4 Kg7 27. Rf2 Rd6 28. Rdf1 Rdd8 29. Qc2 b6 30. h5 c5 31. hxg6 dxc3 32. bxc3 c4 33. d4 exd4 34. cxd4 Nxd4 35. Nxd4 Rxd4 36. e5 f5 37. Bxf5 Qd5 38. Be6 Rh8+ 39. Bh3 Nxg6 40. Rf7+ Kh6 41. Qxg6+ Kxg6 42. R1f6+ Kg5 43. Rf5+ Kg6 44. R7f6+ Kh7 45. Rh5+ Kg7 46. Rg5+ Kh7 47. Bf5# *

I will try to pin all the games I can find in the show so this list is likely to grow.

Yes it correctly describes the  life of a chess player. Wesley So has been adopted. The face of Alexandra Kosteniuk. Prodigy of Morphy. Life of Fischer against the Russians. Drinks of Alekhine. Beth Harmon is the combination of the lives of the greatest chess players.


How to play for a draw In this video: Levon Aronian vs Magnus Carlsen Round 1 - 2013 Candidates Chess Tournament

[FEN ""]
1.d4 Nf6 2.c4 e6 3.Nf3 Bb4+ 4.Bd2 Bxd2+ 5.Qxd2

And now, Kevin said: "You can tell that the game is going for a draw."

My question, how can you play a game knowing that you are going to draw? Do you have to defend? Exchange minor pieces? Mirror your opponent's move?

In theory, white always plays for a win, so how can black say: "I'm going to play this game and I'm going to draw". Carlsen seemed that he decided to go for a draw from the get-go, so what's the game plan for black in order to get a draw?

I imagine Kevin's comment was somewhat hyperbolic. My local database has 1464 games with the position after 5.Qxd2, of which only 47% were drawn (although I imagine that percentage goes up as the players' strength increases). That is still enough to give the variation a reputation as drawish, but not enough to reliably predict that the game will end in a draw.

There are certainly variations that are more drawish than others, for concrete reasons. The best current example is the Berlin variation of the Spanish, where Black gets the queens off the board early and White has had trouble making anything of his positional advantages in the ensuing endgame.

In general the way that a game becomes more likely to have a decisive result is due to imbalances between the virtues of the two sides. The obvious example is a gambit, where one player has better development and the other player has an active pawn. In a situation with few imbalances (for example, the Exchange French or Exchange Slav), it is more difficult to play for a win.

There is no "playing for the draw" in chess.You always play for win.


What's the rationale behind chess engines conditionally allowing threefold repetitions when assigning a draw score? When a chess engine sees a position p repeated once (i.e. position p occurred twice) it immediately assigns the second occurrence of position p a draw score. This makes sense because position p doesn't need to occur thrice in order for the chess engine to realize that it's not making progress (i.e. a twofold repetition is just as drawn as a threefold repetition).

Many chess engines do just this. They assign a draw score to all twofold repetitions. However, some of the best chess engines such as Stockfish and Ethereal don't assign a draw score to all twofold repetitions. If the first occurrence of position p is not strictly after the root node then they don't assign a draw score to the twofold repetition. Instead, the position needs to be repeated twice (i.e. it needs to be a threefold repetition) in order for it to be assigned a draw score.

For example, consider the following drawnByRepetition function from the Ethereal source code:

int drawnByRepetition(Board *board, int height) {

    int reps = 0;

    // Look through hash histories for our moves
    for (int i = board->numMoves - 2; i >= 0; i -= 2) {

        // No draw can occur before a zeroing move
        if (i < board->numMoves - board->fiftyMoveRule)
            break;

        // Check for matching hash with a two fold after the root,
        // or a three fold which occurs in part before the root move
        if (    board->history[i] == board->hash
            && (i > board->numMoves - height || ++reps == 2))
            return 1;
    }

    return 0;
}

As you can see either i must be greater than the root node (i.e. it must come after the root node) or the position p needs to be repeated twice (i.e. it must be a threefold repetition) for it to be assigned a draw score.

The chess programming wiki has the following to say about assigning draw score to repetitions:

  Threefold repetition implies a position occurred thrice, that is repeated twice. When to score the position as a draw, however, is an entirely different matter. Most programs do this on the first repetition, no matter whether the first occurrence of the repeated position appears in the current search space, or not. Other programs consider that fact, they avoid cycles inside the current search tree to make it a directed acyclic graph (DAG), but allow a one-fold repetition, if the first occurrence appears in the game history before the current root. Anyway, to wait for the second repetition one has its pros and cons. The Repetition score is either zero or the contempt factor.

It says that “to wait for the second repetition one has its pros and cons.” So, what exactly are the pros and cons? I couldn't find an explanation as to why top chess engines like Stockfish and Ethereal do this.

It says that “to wait for the second repetition one has its pros and cons.” So, what exactly are the pros and cons? I couldn't find an explanation as to why top chess engines like Stockfish and Ethereal do this.

My discussion will be technical, so let's make it as simple as possible. Firstly, let's make be clear about this:

  If the first occurrence of position p is not strictly after the root node then they don't assign a draw score to the twofold repetition.

Why would an engine do that? Let's consider two scenarios where we have three-fold repetition during the search. Let's assume we are on move 30th, and the engine is thinking at move 40th.

The position repeated and played on the board, for example, the position occurred on move 24th and 26th.
The position never actually played on the board, but it is part of the search. The position occurred at move 35th. (IMPORTANT - only a single repetition)

Scenario 1

In the first scenario, it's a repetition that we all understand. In your code example:

++reps == 2

So, if a position repeated twice earlier in the game before the root (root == current board position), it's a three-fold repetition. Very simple.

Scenario 2

What about the second scenario? You have the identical position on move 35th, and the same position come back on move 40th. Thus, it's reasonable to assume if you search further you will encounter the position again (for the third repetition). For example, move 45th.

Your code example:

i > board->numMoves - height

  So, what exactly are the pros and cons?

Pros: search quicker and deeper

Cons: you assume the same position would occur again later in the search (e.g. move 45th), which is not always true

  I couldn't find an explanation as to why top chess engines like Stockfish and Ethereal do this.

Search quicker and deeper. Common optimization in modern chess programming.

Let's say your engine sees the best moves in a position as +0.08 and +0.06. It plays the +0.08 move and the opponent replies. In the new position, the engine realizes that it was slightly optimistic, and the best continuation is now +0.01 unless it repeats the position. I think it makes more sense for it to evaluate the repetition as +0.06 than a flat 0. It is, after all, not an automatic draw to repeat the position once.

It is, of course, very possible that after the engine repeats and plays the +0.06 move, it will again find that it was optimistic (perhaps for the same general reason) and now the best move is -0.01. Perhaps it now missed its chance to get the +0.01.

So, which scenario is more likely?


Looking for website for organising private tournaments with swiss system? Do you know any website for organising online chess tournaments with swiss pairing method ? I know lichess.org but they don't support it anymore :/

The related question How to organize a chess tournament appears to have several suggestions; I'm not personally familiar with any of them, but most of the links seem to still be active.

You can try chess.com, but you must be a premium user to create a tournament.


Is chess a good game for recovering addicts? In this interview to FIDE Master and psychologist Maria Rodrigo the interviewer asked her about chess and addictions:

XL. There are those who are not able to prioritize and get hooked.
M.R. Yes, because the dopamine rush during a game can be brutal. And that is something you have to learn to control. If you don't, you start a game, and then another, and another… And there is no one to stop. You lose hours of sleep… The problem of addiction is more typical in men than in women. Men are more hooked on video games and women on social networks.

I am a recovering addict. I passed through this clinic in Barcelona to recover from my addiction to alcohol and cannabis. They had a group where they used chess as therapy, so as a lover of the game I said to myself that chess couldn't be harmful for my therapy. But they banned me from chess, arguing I played obsessively. They said I could play once my two years treatment is finished. It was true that I played lots of online blitz, but I felt disgusted: why was I banned when they used chess as therapy for others?
Nowadays, I am in the ninth month of recovery. I left the clinic and I went to a psychologist. I don't play online blitz, but I play correspondence and I joined my club to play standard over the board games. My psychologist approve it but he is not specialist in addictions. At the clinic they wouldn't approve I am playing before two years of recovery.
I can read articles like this one on Chessbase where it is said they started a cognitive training through chess at a therapeutic community "recovering the cognitive functions (attention, memory, etc.) deteriorated by drug use, with the help of chess". But maybe this is focused on teaching how to play chess to people that didn't play lots of online chess while consuming drugs. And dopamine plays a role in addictions. At the clinic they said we were addicts to dopamine highs, so reading FIDE Master Rodrigo I would say it could still be harmful to my therapy and bring me closer to a relapse.
It is clear chess is good to treat other mental diseases like schizophrenia, and it looks good to teach recovering addicts how to play chess to recover the cognitive functions damaged by drug abuse (according to Chessbase article and my clinic), but is chess good for a recovering addict that played chess before his treatment started? Can it bring the patient closer to a relapse in drug use?

Stack Exchange has a site dedicated to medical sciences.
If you open that, you'll immediately see that on the right column there's a disclaimer that you won't find on any other Stack Exchange site. It's a bit long, so let me cut the most important parts:

Stack Exchange Inc., and its sites including Medical Sciences Stack Exchange, is not a medical practice or healthcare provider and does not provide medical advice.
[...]
Consult your own doctor for medical advice.
[...]
Medical Sciences Stack Exchange is for information exchange only, and is not a substitute for medical advice, individualized diagnosis or treatment by a healthcare provider.

This obviously covers the legal aspect, but it's more than that. Even if there were no lawyers and lawsuits in this world, that disclaimer would still have value. Because, well, it's true. In general you cannot trust users on any of these sites to really know what they are saying. Your health is too important to blindly trust some random stranger on the web, no matter how high their reputation is or how sincerely they are trying to help.
Besides, it seems to me that you've already got the answer from your clinic:

But they banned me from chess, arguing I played obsessively.

I'm sorry, but I'm afraid you'll have to accept it.
I hope I won't sound judgmental if I tell you that what you are really doing here is not looking for an answer (you've already got one; only, it's one you don't like), but rather for an excuse that will let you keep playing and ease your conscience.
Imagine someone posted an answer along the lines of

Don't worry, those doctors don't understand anything! Playing chess can't be a problem, just go ahead and play as much as you want!

I suppose you'd be very happy to read it. And yet, who would you rather trust: the doctors that visited you and know your case specifically, or someone who probably has no idea what they are talking about, and who certainly doesn't know you, your clinical history, anything about you at all?
So do the right thing, and do what your doctors say. Or in any case discuss with them what you should do.
My best wishes for your full recovery!

Yes, of course.
Any game - any activity - that depends on continued application of the powers of the mind should help recovering addicts.
Unless no games are good, how could chess not be?


Why is it a good idea to fianchetto above the castled King? If I do that, should I make sure to leave the Bishop there for a while to guard the hole? I understand why fianchettoing can be helpful, even deadly to an opponent, but should it really be done on the side which the King castles into?  I realize that the King's Indian Defense/Attack involves fianchettoing on the kingside as well as castling to the kingside, for Black and White respectively; and that that position is quite strong.  But I'd like to know the principle behind opening up the N-pawn above the castled King.  Is it a weak point?  And if so, should I be careful not to move my Bishop from the fianchetto square?

I suppose more generally my question is: what should I be careful of when advancing a pawn in front of a castled King in the early to middle game?

Fianchettoes are a very common and strong setup. But watch also for the 2 most common attacks against a fianchettoed position, which are:

A. Launching the rook pawn up the board (against Black this would be h4-h5 etc.) and opening up the h-file. I have played this many times against the Pirc where Black "castles into" the attack. White plays h4-h5 followed by trading off the pawn and then plays Qh6+ with a very strong attack down the open file.

B. The sacrifice of a knight on f5 (where Black accepting the sac would play ...gxf5). This wrenches open the position and jacks up the pawn structure.

Even if the opponent trades his same-color bishop for your fianchettoed bishop, you can still become weak on that color complex (e.g. the opponent's queen can roost on h6 for example and be a thorn in your side)

Logical fallacy.
Assumes the consequence.

It may be good and it may not.

I have mated many opponents who had a fianchettoed B in front of their king.


Why is the Alekhine Defense named after Alekhine? Alekhine, a world champion, has his name on the defense Nf6 in response to White's e4. But after e.g. 2. e5 Nd5 3.c4 Nb6 4. d4, White seems to have a good game.

Did Alekhine win any notable games (or tournaments) using this defense? Did he publish any books or papers successfully defending this line? What did he see as its merits?

You're right in that white seems to have a good game. But in reality, not much more than that. Black continues with 4. ...d6, and can go into many variations such as the optimistic, but shaky Four Pawns Attack with 5.f4, Exchange variation with 5.dxe6, where black can respond by taking with either pawn, and will usually follow up with a kingside fiancetto if he takes back with the c-pawn. Of course, there are other variations such as the Balogh, Two pawns attack, Two Knights variation, Scandinavian variation, Modern variation (perhaps the most challenging), etc. Look them up if you wish. Black's basic idea is to get white to over-extend his center, creating targets in the form of pawns and the weaknesses left in the pawns' wake, and then undermine those weaknesses with pieces. Again, white seems to have a good game because of the classic space advantage in the centre. BUT, that's black's plan - The Alekhine Defence is a hypermodern idea, so black voluntarily gives up the centre in the opening, just to challenge it later on from the sides.

According to chessgames.com, the Alekhine's Defence has a win rate of 33.4% for black, which is very, very respectable; especially when compared to other very highly respected openings such as the Caro Kann, French, Najdorf etc.

I don't know if Alekhine himself won tournaments using just this defence, but here are a few games where he successfully employed it against strong opponents: Bogoljubov, Maroczy, Mieses, and a lesser known, but still strong Sergeant. The last game is a famous positional crush featured in a book I have on the Alekhine Defence.

Besides Alekhine, many world champions have employed it throughout history, such as Capablanca, Euwe, Tal, Bronstein, Fischer (remember the famous Spassky vs.Fischer 1972 game?), Smyslov, Petrosian, Spassky, etc. Even Carlsen has employed it now and then as a surprise weapon. Check out Carlsen vs. Topalov.

To conclude, I don't think its possible for anyone to answer why Alekhine introduced this defence (if he did), and what merits he saw. However, he must have certainly judged it to be a playable opening that matched his style (aggressive). But as I've outlined, it has become a formidable surprise weapon over time, and is even used nowadays at the very top level in major tournaments.

The moves 1.e4 Nf6 were played before Alekhine (analyzed by Allgaier in 1819), but Alekhine popularized it.  Alexander Alekhine first played this defense at Budapest in September 1921 against Saemisch and E. Steiner.  By May 1922 it was being called the Alekhine’s Defense by Sir George Thomas in the British Chess Magazine.  Also in May 1922, Hans Fahrni wrote the first monograph on the opening, calling it Die Aljechin-Verteidigung.


How to deal with the pinned knight on f3 in the Ruy Lopez (as white)? I find myself in positions like this a lot when playing the Ruy Lopez:

[fen ""]

1. e4 e5
2. Nf3 Nc6
3. Bb5 d6
4. O-O Bg4

If I try to kick the bishop out with  5. h3, they back up to h5 and I'm in the same spot I was, essentially. What tends to end up happening is after my queen comes out, they take on f3 and I end up with doubled pawns, which makes me pretty uncomfortable on my King's side.

So what's the best way to deal with this pin? Or are doubled pawns a typical consequence of playing this line? Maybe I could have done something earlier? According to the chess.com database, this isn't a super common line anyway.

Black cannot exploit the pin with ...Nd4: not at once because the Nc6 itself is pinned, not later because c2-c3 is on your plan anyway. This means that you should not panic and can concentrate on developing before taking measures about the Bg4.

You should not be afraid of a ...Qf6 either. After the later sequence ...Bxf3, Qxf3, Qxf3, gxf3, your king is secure thanks to the queen exchange, and the bishop pair is much more important than the temporary doubled pawn that you would get rid of by pushing f3-f4, gaining influence in the center in the process.

If you follow a Ruy Lopez plan anyway: c3, d3, Nbd2, Re1, Nf1 you have various ways of breaking the pin.

First, you can move your queen when the second knight is on d2. Plus: it is faster. Minus: your queen don't have so many great square to go to, since on c2 it is a bit passive and that square is better left for a possible retreat of the Bb5.
Second, you continue, after Nf1, with h3 (check whether the opponent can reply ...h5 when his rook is still on h8) and after ...Bh5, Ng3. It is part of your plan anyway (reinforce e4 so you can push d3-d4, possible knight-hops to f5 or h5) and it embarass Black's light-squared bishop. After an eventual ...Bxf3 Qxf3, you gain the bishop pair with excellent chances to build an initiative on the light squares.

Learn to play the Ruy correctly.   h3 is needed before castling.