11 August 2022

Two Pigs

Edward Winter has published several entries in Chess Notes over the years inquiring into the origins of the checkmate pattern often called blind swine. The term "blind swine" for two rooks on the seventh that cannot find checkmate was credited to Dawid Janowsky by Vladimir Vukovic (see CN 5160). Winter seeks a primary source that confirms Janowsky used the term. None have been found. The phrase has been credited to Aron Nimzowitsch as well (CN 3525).

This morning I had two rooks on the seventh and was playing for a draw because I failed to see a resource: my f-pawn could advance to support one of the rooks and produce a different two rook checkmate. In my defense, it was early morning, my first game of the day, and the game was one minute plus one second increment. Such a time control does not produce accurate play.

Stripes,J. -- Internet Opponent [D06]
Live Chess Chess.com, 11.08.2022

White to move

27.b4?! d4 28.exd4 cxd4 29.Rc7+ Kg8??

29...R8e7=

30.Rxa7 Re2+ 31.Kg3 Rd8

31...R2e7 32.Rxe7 Rxe7 33.Rc8+ Kf7 34.Rd8+-

32.Rcc7

White has two rooks on the seventh, but how is this enough to win?

32...d3

White to move

33.Rxg7+ Kf8 34.Raf7+

34.Rxh7 threatens mate.

34...Ke8 35.Rc7 Kf8

White to move

36.Rcf7+

I could have played: 36.Rxh7 Kg8 37.f5! The key move that escaped my notice.37...d2 38.Rcg7+ Kf8 39.f6 and mate comes soon.

36...Ke8 37.Rc7 Kf8 38.Rxh7 Kg8 39.Rcg7+ Kf8 40.Rf7+ Kg8 41.Rfg7+ Kf8 42.Rf7+


White seems to be playing for a draw. I was because my fear of Black's d-pawn rendered the power of my f-pawn invisible.

Black to move

42...Ke8?

42...Kg8 White must find 43.f5, which White has already shown is beyond his capacity.

43.Rc7 Re7

White to move

44.Rh8+

White finds a tactic to create the opportunity that was already on the board. It is not the rooks that are blind.

44.Rcxe7+ Kf8 45.Rb7 Kg8 46.f5

44...Kf7 45.Rh7+ Kf6 46.Rcxe7 d2 47.Rd7 White won on time 1-0

04 August 2022

King Safety

Working through the games in Kevin Wicker, 200 Modern Brilliancies (1981), I came upon this mess from a postal game between Toni Cipolli and Semen Gubnitsky played in 1977.

White to move
Cipollini did not find the right idea. Nor did Wicker.

31 July 2022

Think

It was my hope that after one full week of playing bishop endings against Stockfish on Chess.com, I would be able to report success. I had a completely winning position in the fifth and last exercise in the set yesterday morning when a single hasty move threw away the win. I can blame the distraction that caused me to look away from my iPad, but by now I should know to look at the board before moving when I look back.

This morning, the computer threw me several curves in exercise number three and I failed each time. This was one instance.

White to move

I played 1.a4?? and after 1...Bd8+ 2.Kc6 Bxa4, there was no way to prevent the loss of the g-pawn, too.

Later, I set the position up in the Stockfish app and won easily.

Several times this week, I have played 1.a5 in the position below. The resulting draw is a position that I should recognize by now.

White to move


29 July 2022

Overworked Piece

I failed my bishop endgame this morning. It was number two in the series described in "The student should work this out". I was doing fine until I reached this position. Then, I went from winning to losing.

White to move
What would you play?

28 July 2022

"The student should work this out"

In Chess Fundamentals by José Raúl Capablanca, the author frequently states that a given position, "should be worked out by the student", and other comparable phrases. This assertion vexes some readers and some coaches are loath to recommend the book. If the student does not understand something, how will they come to an understanding without assistance?

In some cases, especially with simple pawn endgames in chapter 1 of Chess Fundamentals, I believe that Capablanca provides the necessary resources in the explanations that he offers. Still, I have seen others struggle. They need more help. Capablanca recommends a teacher.

When Capablanca wrote Chess Fundamentals (he was checking the proofs in England in 1920 while negotiating conditions for the World Championship Match that took place in March and April 1921--see "WCC Havana 1921" in this site's index), there were fewer resources than we have today. I believe the standard endgame book then was Johann Berger, Theorie und Praxis der Endspiele (1890), a book in the German language that was probably not readily available or accessible to the majority of Capablanca's readers.

Today, however, we have an abundance of books, websites, YouTube, ready access to engines, and even tablebases. The danger to the student stems not from lack of help, but rather too much help. Easy access to answers cause many to fail to develop self-reliance. Capablanca's call to develop the habit of working things out may offer a more certain formula for strengthening a player's skills.

I often claim that I have zero natural ability at chess, but that I have learned a modest amount from books (see "My First Chess Book"). Many years ago when I started reading chess books, I found much that was confusing. The book I remember most clearly is Irving Chernev, The 1000 Best Short Games of Chess (1955). Often it was not evident to me why a game ended. Sometimes Chernev explained the reason, but even then I had questions. I sought answers to my questions by moving the pieces on a chess board, exploring variations. Certainly, with so little skill at the time, most of my fantasy variations were rubbish. Even so, the effort developed a habit of thinking for myself about chess.

The past few days I've found myself back in the classroom, seeking understanding. I started playing some bishop endgames against the computer on chess.com. Failure in my first effort got me hooked. My time struggling through five positions against the silicon monster engages me for hours every day. At the Learn/Endgames/Minor Pieces/Bishops tab on chess.com, there are five practice positions. To see the second one, you must checkmate the computer in the first. The first is simple and takes me from 12 to 24 seconds most times. 

The second one varies in difficulty, depending on how the engine plays.

White to move
Number Two
1.Bf5

I always play this move. It might be best.

1...h5 2.f3

Now the engine has played 2...a5, 2...Ke7, and 2...Kc6 most regularly. 2...Kc6 has proven most testing but I am reliably winning most of the time. Success grants me the opportunity to see number three.

White to move
Number Three
I found the pawn sacrifice quickly and now get to my seventh move in two seconds or less. Sometimes I reach this point with considerably less than two minutes total time elapsed for checkmating the computer in the first two and playing these seven moves.

1.c5 dxc5 2.Bc4 Bg4 3.Kxe5 Ke7 4.Kd5 Kxf7 5.Kxc5 Ke7 (the computer threw me a curve with 5...Kf6 at least once) 6.Kxb4 Kd6 7.Bd5

Black to move
The computer has played at least five different moves here.

a) 7...Bf3 proved challenging the first time I saw it. That line now often continues 8.Ka5 Be2 9.b4 Bg4 10.Kb6 Bh3 11.b5 Bg4 12.Ka7 and the computer must give up the bishop for my b-pawn.

Black to move
12...Kc5 has given me trouble when I am moving too fast, which the exercise encourages by tracking total time for the series and making me play simple checkmates all the way to the end. Sometimes I underpromote to practice bishop and knight or two bishop checkmates.

13.Bc6 Bc8

Here, 14.b6?? fails, but both 14.Kb8 and 14.e5 succeed.

I have seen most of the computer's responses several times, but this morning's effort presented me with a position I did not recall seeing before. 

b) 7...Bd7 8.Ka5 Kc7 9.Kb4 Kb6

White to move
10.Kc4!

There is more than one way to get rid of Black's bishop.

10...Be8 11.Kd4 Kb5 12.e5 Kb4 13.Ke4 Kc5

White to move
14.Bg8 Bc6+ 15.Kf5 Kb4 16.Kf6 Kc3 17.Bc4 Bd7

This move is Stockfish surrendering it seems.

White to move
18.e6 Bc6 19.Kf7 

Black must give up the bishop for the e-pawn. A few moves later, I underpromoted the b-pawn to a bishop. When I was nine or ten moves from mate, I made a hasty move that stalemated the engine. Now, I must start over at number one. I've played number five half a dozen times and have some ideas how to proceed. My current problems are two: 1) the engine lures me into a pawn ending that is lost foe me, and 2) I fail two, three, and four too often.

Have you tried these exercises? How did you do?





27 July 2022

Checkmate Challenge

My online chess camps this summer have been competing with one another in the checkmate challenge. The challenge consists of 30 minutes of solving as rapidly as possible checkmates in one move. I use a database of 101 exercises that I downloaded from the web so long ago that I no longer know where or when. I believe it may have been Gunther Ossimitz's now defunct chess site (see "Gunther Ossimitz PGN Files").

The first ten exercises are mate with a rook. Then there are ten with a bishop. These are followed in succession by mates with a knight, a queen, and then pawns. Three involving en passant captures usually slow the students down, and I often need to explain the rule.

White to move
Mate in one
Some pawn mates are the pawn delivering the final check. Often, the pawn promotes to a rook or queen. In one case, the pawn must become a knight.

After the en passant mates, there are some double checks mixed with other themes. The exercises grow slightly more difficult. I like the structure of the database, which resembles the structure at the heart of the work of Viktor Khenkin. See "Two Old Books (and one new)" for more about Khenkin.

Many of the exercises are composed, and the early ones have few pieces. Some are from familiar games, such as Morphy's Opera Game

My students have included a handful of strong youth players, but most are beginners. Some of them have been playing chess a week before camp begins. I ask the students to shout out answers or type them in the Zoom chat. Speed matters. Wrong answers are ignored if the right answer comes fast enough.

Many groups have solved 60-70 of the exercises in the 30 minutes. Three groups have solved all 101! Today, a group solved the whole set in 27 minutes. Last week, a group did so in 26 minutes. One group with some skilled players whipped through the entire set in 18 minutes.

These are some of those that slow the students in their quest. It is always White to move.





12 July 2022

Coaching: Constructing a Lesson

I had been coaching youth chess for a couple of years when I decided to keep a clear record of what I did each week with the students at the elementary school where my youngest was no longer a student. While he was enrolled there, I was a parent volunteer helping with the after school chess club. When he moved on to another school, I returned to his old elementary as a paid chess coach. The year was 2004. Chess club started in late September.

I began the year with a position from a game I had played a day or two earlier on the Chessmaster Live server. Although Black had a one pawn advantage in a king and pawn endgame, it should be drawn with correct play.

White to move
My opponent erred with 46.Kc5?? We both promoted pawns, but then my opponent blundered theirs away. Had we continued in a queen ending, White might have held out long enough to run me short of time. Black was technically winning with QPP vs. QP and Black's king closer to the pawns.

Instead, play might have continued:

46.Ke4 Kf7 47.Ke5 Ke7 48.Kd4 Kd6 49.Ke4

Black to move
Here Black can err with the same flawed idea that White pursued in the game: 49...Kc5?? Correct play would be either 49...Kd7 or 49...Ke7 and a technical draw.

In the lesson, I sought to introduce to the students the concept of opposition in pawn endings. I followed this position from a recent game with a number of other positions, mostly composed, that had fewer pawns and presumably simpler continuations.

The school chess club ends the year with the Washington State Elementary Chess Championship in April. The last session before state, I showed the students a pawn ending that had been played at the Spokane Chess Club the week prior.

Black to move
After the game ended as a draw, I spent some time with others at the club, including the one who had Black, arguing about whether Black had a win. The next day, I checked some of our ideas on my computer. If we had the same argument today, someone would pull up Stockfish on their phone or a tablebase site and end the debate. My phone then was a RAZR flip phone. It's chess app was a version of Chessmaster that I could beat on its top level.

Had any of us read with sufficient comprehension José R. Capablanca, Chess Fundamentals (1921), we would have known how to use triangulation to secure the win after 1...g5. I had nearly forgotten this lesson until I was playing through an ending presented in C.G. Van Perlo, Van Perlo's Endgame Tactics, new, improved and expanded edition (2014). The ending came up in my study as I was comparing endgame books for "To Know a Position", which I wrote last weekend.

For the children headed to state, I hoped to reinforce some lessons I thought they should have absorbed in September. It is always hard to measure results, but both the elementary team (grades 1-5) and the sixth graders from the middle school brought home trophies--individual and team. School officials perceived me as a successful coach and I have continued to coach youth players.

The lessons I employed that first year as a chess professional at an elementary school were compiled into a booklet that I printed at the school and then had bound at Kinkos. I have learned a lot in the years since. My skills as a teacher have improved. My chess playing ability also rose. I have also learned to print my lessons through Amazon, where I get better quality binding at lower cost, and also am able to make them available to others.

11 July 2022

Grigoriev Study

As mentioned in "To Know a Position" yesterday, a 1921 study by Nikolai Grigoriev appears in several books, especially Dvoretsky's Endgame Manual and Alex Fishbein, King and Pawn Endings. However, I did not find the study with that date in Harold van der Heijden, Endgame Study Database VI. Rather, the position is flipped and the date given is 1924. Otherwise, it is the same position.

White to move

White must play precisely to draw.