Monthly Archives: November 2016

Elements of checkmate

When the king is checkmated there are 3 factors to look for:

  • The king is in check!! Check this first!
  • The king has no flight squares
  • There is no way to block the check(s)

If any of the above are untrue the position is not checkmate and the game is not over!! (unless it is stalemate.

Elements of stalemate:

  • The king is not in check!!
  • the king has no flight squares
  • all other pieces have no legal moves, ie they don’t exist or they are in absolute pin or are in a perfect prison where they are blocked from moving any where.

These rules may sound nuanced and eccentric but they are the official rules of chess that almost all chess players abide by. These rules of checkmate and stalemate are agreed upon pretty much worldwide and no one is contesting them, however in the mid 1700’s the rules of chess were not fixed and games sometimes went on without one sides king till all the pieces were captured and in some games and bullet chess in real life, is that capturing the king is the same as checkmate in that it wins the game. When the king is en prise (pronounced like en prie), the king being captured is either a win or it means the last known legal position should be setup again and have play continue from there. When entering a tournament make sure everyone is clear on these rules or at least that you are, in case it happens in a real game.

When you fully understand checkmate and many of it’s variations then you will get better at chess. I highly recommend learning all of the rules of chess, including en passant, the fifty move rul and threefold repetitio and absolute and relative pins, it is then, when you know all the rules, that you can begin to get good at chess!

There are 5 ways to draw a chess game, they are:

  • Drawn by agreement
  • stalemate
  • insufficient material
  • 50 move rule
  • threefold repetition

Draw by agreement

When the game is in play, you may propose that the game is a draw and offer a draw to your opponent. If he accepts the draw off the game ends and both players get a draw score which is usually 1/2 – 1/2 the point is divided in two and given to each player. In classical chess the scoreboard sometimes counted a draw as 0 – 0 no one got the rounds point!! But this is cruel!


When the game is stalemate you have no legal moves and the king is not in check, you should call an arbiter right away to confirm that the position is in fact drawn. When the arbiter verifies that the position is drawn you will both get half a pint for the tournament round.

Insufficient material

When the material on the board will be impossible to checkmate the enemy king the game is regarded as drawn, best to confirm this with an arbiter as well.

If there is a pawn anywhere on the board that is sufficient material to checkmate since they have the potential to promote. Any position with a pawn anywhere on the board wether it is blockaded by other pawns or not, is sufficient material to continue play!

If all the pawns are gone and all the pieces have traded off and there are only two kings left this is an insufficient material to checkmate since one king can never checkmate another king.

If there are two bishops on the board, it is known that two bishops and a king vs a king can checkmate (but no pawns or other material). If only one bishop and the black and white king are on the board, this is insufficient material and is a draw! 1/2 – 1/2.

If there are a black and white king and just a rook that is enough to play on though will likely win with best play, contact an arbiter if in doubt!

If however there are both kings and two knights this is a draw. Two knights and a king cannot in almost any possible position checkmate an enemy king!!! (the position is not acheivable without hitting stalemate first).

if there is a rook or a queen left that is sufficient material to checkmate the enemy king. (not yet drawn or won).

Fifty Move Rule

If there has not been a pawn move or a capture for the last fifty moves the game can be claimed as a draw since very little position progress is likely to happen in that scenario.

You can also call it 50 moves without a pawn move or capture draw. I guess.

That includes moves for both sides, so 100 ply’s total.

Threefold repetition

If the same position has occurred 3 times or more in the same game, a draw can be declared by either player.


Rules of thumb and opening principles

If you have ever been taught chess by an instructor, they will give rules of thumb like “don’t bring your queen out early, keep your king behind pawns, castle early, don’t move the same piece twice develop your pieces not your pawns!, none of these are hard rules, break them all you want it will help you learn. If you or your opponent moves your queen out on move 2 or 3, you can’t call the arbiter and complain that it’s wrong, it probably is wrong but the consequences will present themselves in the game. The only thing these rules do is make your play ‘look’ like master or grandmaster play, but will not win you a game against a real grandmaster/im/fm if you don’t know your tactics and your end games!!

If your opponent breaks opening principle rules you must punish him over the board with better moves and good moves. You can’t make your opponent not move his queen on move 2, if he wants to he can, but you can *sometimes* trap the queen on the open board but that’s another lesson!

Double check, checkmate lesson

In chess there is a way to give a discovered check where the piece moving will give check and reveal a line of attack behind it Knights are good at this but bishops and rooks can also sometimes move to give double check.


fig 1a. Is this checkmate? Yes/No


fig 1b, I have removed blacks bishop on d6, is it still checkmate? Yes/No


fig 1c. I have removed just the knight and the bishop is back is this position checkmate? Yes/No

Well yes the first diagram is checkmate, the other two are not checkmate!!

When the king is in check from two pieces at the same time, because you can only block a lineof attack in one one move and you cannot block two lines of attack with any piece move from any square!! In figure 1b the knight gives check and can be captured in one move, and in fig 1c the bishop only gives check and can be captured or the line of attack can be blocked with the pawn moving one square forward. In figure 1a the bishop and the knight cannot be captured in one move, if it were allowed, the knight would be captured and the king is still in check from the bishop, or alternatively if the bishop is captured or blocked the knight still attacks the king.

This is why double check is so powerful. In figure 1a, we know that it is double check and the king must move that is a rule now! but the king is never allowed to capture it’s own sides pieces or pawns so all it’s squares are killed off by the pawn on h3 and g2 and g3 is attacked by the bishop and the king can only move one square in any direction, the rook attacks h1 and g1 flight squares from f1. The king is checkmated. There is no escape square or block or capture.

Alternatively if you take away the f1 rook it is no longer checkmate as the king has two flight squares g1 and h1.




Chess as Science

I think it’s safe to say that computers (and software) have chess down to a science. That is an expression that means computers are really good t chess (now).

But what is the definition of a science? The definition of science is that you record all pertinent data, and usually you can reproduce those results in a lab and you can make observations and statements about those results, the law of gravity is a science because here on Earth anyone can observe gravity and make statements concerning gravity. For one it makes things fall down to the Earth!!! But this isn’t too important to my topic.

Chess is like a science!! We have names for openings, endgames, opening traps, checkmates, we call a bad move a mistake, a really bad move is called a blunder, a tiny mistake is called an innaccuracy, we have good moves and excellent moves.

The fried liver attack!!

We now know with the aid of computers that the fried liver attack, has a few bad moves from both sides, but it’s the positions that have a few mistakes that make for the most interesting and beautiful.

There are mating traps with names, like “Scholars mate” and “fools mate” .. here:

KPK – King vs Pawn and King endgame

With the board down to 2 kings and 1 pawn there are still ways to draw if you get the right positions, but there is still possibilities to win with the side with a pawn.


In the first 10 moves there are billions upon billions of possible continuations and openings possible!!In those 10 moves there are still billions of billions of logical continuations possible, even pawn gambits and sometimes piece gambits are logical and playable!!


Chess facts:

“Anything is playable” Hikaru Nakamura

[Event “13th Sigeman & Co”]
[Site “Copenhagen/Malmoe DEN”]
[Date “2005.04.22”]
[EventDate “2005.04.15”]
[Round “7”]
[Result “0-1”]
[White “Hikaru Nakamura”]
[Black “Krishnan Sasikiran”]
[ECO “C20”]
[WhiteElo “2657”]
[BlackElo “2642”]
[PlyCount “174”]

1. e4 e5 2. Qh5??!

In a Grandmaster/International Master level game Hikaru played Qh5 on the second move in the King’s Pawn Game opening against Krishnan Sasikiran, and went on to win the game as well, proving that anything is playable. Now masters always teach their students “Don’t bring out your queen too early in a chess game”, however there are exceptions to this rule, it is not usually found in IM and GM play. Not only does it break those hidden opening rules that you shall not break, it’s rude and the opponent isn’t prepared for outright craziness in the second move in chess, so it may win psychologically.

1. e4 e5 King pawns game study (and middlegame)

Here in this video around the 18:30 mark, I have played this in the last couple decades as black and thought that the position was lost for black, but actually the computer gives it as small advantage to white. Which if you don’t understand the value of positions means that black still has good chances to draw the game. My early chess mentor taught me there is always compensation (when you follow opening principles but lose material), you just have to find the right moves.

Game: 1. e4 e5 2. Nf3 Nc6 3. Bc4 Be7 4. d4 exd4 5. c3 dxc3 6. Qd5 Nh6


The stockfish engine gives this position 0.38 to white which means it’s drawish!! Despite Bxh6 winning the knight after castling black found the only way back to king safety but now white has issues with capture on b2 threatening to win a rook and queen a pawn, after 7 .., o-o 8. Bc1? Nb4! with long term queening threats in his future w/ pushing to c2 among other things. Engine moves suggest 9. Qh5 Nc2+! (+0.89 in blacks favor Nc2 or b5),  10 Kf1 and white has problems.

Openings are hard for humans to evaluate as good as computers can, even computers can have trouble in the openings and they still do! Deepblue’s opening book was constantly being tweaked by Grandmaster Joel Benjamin throughout the match between DeepBlue and Kasparov 1996-1997. It is usually up to the programmer to set the computer in the right direction in chess openings otherwise we get some different kinda weird and “off the beaten path” games, because of the diversity of possibilities in the early moves of chess computers can find openings unclear as well.

full video here

In early computer chess, before there was great cpu power and memory, engines without a built in opening book would play silly things like putting bishops on e3 or d3 in front of pawns on either d2 or e2, bringing the queen out on move 3, mostly unheard of in Grandmaster play even master play. Though there are exceptions where it can be good, computers were a laughing stock in chess up till the mid 90’s and master strength computer software was far and few between.

In chess, computer scientists name this the ‘horizon effect’ where the computer would only see so deep to the point where it’s evaluation cut off would miss some things that are more obvious to human players, In modern software the programmers work around this in various methods, one of them being search extensions for checks and captures.

Position evaluations, if you use a chess engine you probably want an explanation of what the numbers mean, usually in the opening you will find evaluations really close to 0.00 something like +0.38 or -0.24 aren’t really terribly different, with best play is probably a hard fight to draw for the player that doesn’t have an advantage and a hard fight to win for the player with the advantage, if the engine scores you over 0.80 in the hole you should probably find a different opening continuation since your opponent will likely have the advantage for most of the game, small advantage to white or black is negligible and means the position is definitely playable almost anything up to 1.1 is playable, after 1.78 you are playing a rough game, and your only hope is that your human opponent will make a mistake and you will capitalize on it, so you can equalize the position or better. Anything where you are evaluated 3+ in the hole is respectfully resignable. If the computer evaluates your position as +3 you have  quite a winning advantage of tactic up ahead, like being 3 pawns up or a piece knight/bishop. A rook is evaluated at 5 pawns so being 5 pawns up is like being ahead a rook, or a bishop and two pawns, or a few nice winning tactics at your disposal. Being down 9 or 10 points is like being down a queen, or being down a rook and a few pawns in a generally bad position, you should resign and maybe find a new game with a more equal fitted partner unless you want to play on in hopes of a serious blunder!! Many players will play on down 5 or 6 points in hope their opponent will mishandle the game and allow stalemate by accident, this isn’t wrong! You always have the right to play on even if your opponent has calculated mate, and if he has then all the power to him. You shouldn’t force your opponent to watch your clock go down much longer than 20 minutes maybe even 10 if you should just resign, the arbiter has power to afflict you in certain ways for having bad sportsmanship. Being down 20+ to 60+ points, the computer is about to find mate in 13 and you are in a hopeless endgame, checkmate is imminent.