29 March 2014

Living Dangerously

The Alekhine-Chatard Attack against the French Defense can lead to wild play. In an online blitz game this morning, I had the Black side of a terribly uncomfortable position due to a gross error on move nine. I survived as my opponent and I managed to answer error with error. He made the last significant error and I won.

Nomen Nescio -- Stripes,J [C14]
blitz Some Random Chess Site, 29.03.2014

1.e4 e6 2.d4 d5 3.Nc3 Nf6 4.Bg5 Be7 5.e5 Nfd7 6.h4 a6

I opted for the Maroczy variation.

White to move

7.Qg4 Bxg5 8.hxg5 c5 9.g6 h6??

9...f5 was the correct move.

10.gxf7+ Kxf7 11.Bd3 Nf8 12.dxc5

Black to move

Black has a very unpleasant position.

12...Nc6 13.Nf3 Bd7 14.0–0–0

14.Nh4 is easily refuted by 14...Nxe5.

14...Qa5 15.Ng5+ Kg8

The only move, although White's advantage is still very nearly decisive. In a master's hands, it would be so.

White to move


16.Nxd5! exd5 17.Qf3 hxg5 (17...Nd8 18.Qxd5+ Nde6 19.Qxb7) 18.Rxh8+ Kxh8 19.Qf7 and White has a clear advantage.

16...Nxe5 17.f4 Nxd3+?

17...Qxc5 18.Kb1 Be8 19.Qh3 Nxd3 with a slight advantage for White.

18.Rxd3 Be8 19.Qh3 Bg6

White to move


An error that nevertheless contains a threat which both players managed to overlook.

20.Nxe6 Bxd3 21.cxd3±.

20...Bf5?? 21.Qh5

21.Nxe6 Bxe6 (21...Bxh3 22.Rxg7#) 22.f5+-.

21...Bg6 22.Qh4

22.Nxe6 was still possible, and the queen still immune.

22...Bf5 23.Nf3

Black to move


23...Qxc5 was better with a slight advantage to Black.

24.Qh5 Qf6 25.Ne5 Rc8 

Black appears close to solving his problems.

26.Ne2 Rxc5

White to move

Both sides seem to have even chances. The Black king is finally as secure as White's.


27.c3 or 27.Nd3 was necessary to mitigate the vulnerability of the White king. Having been attacking most of the game, however, White may have found the shift to defensive moves difficult.

27...Bxc2 28.Nxc2 Qxf4+–+ 29.Kb1 Qxg3 30.Qf7+ Kh7 31.Nf3 Qg6 

White to move


32.Qxg6+ Nxg6–+

32...Qxc2+ White resigns 0–1

28 March 2014

Chess at the Science Fair

How does chess connect to science?

A little over a month ago, I received an email soliciting my participation in an elementary school science fair. The email had been sent to the president of the Spokane Chess Club and he forwarded it to me. Without a clear sense of what I should do, I said that I could help.

The school started using the First Move curriculum this year. One of the teachers thought that having chess would be a nice addition to the science fair. Initially, I thought that I would set up a table with a chess set and answer questions. The day before the event, some ideas for a poster popped into my head. I made the poster in two hours that night.

During the fair itself, I played chess with a succession of children. Most of them were second and third graders who learn chess in their classrooms on Fridays. A few were older children and one adult wanted to play near the end of the evening. None of them were strong chess players, but only one seemed unclear on how the pieces move. The children knew how to set up the chessboard. The only error in set-up stemmed from having the White pieces on the first and second rank of a board with coordinates printed around the edges. "Queen goes on diamond," the student said, meaning the d-file. I told her the board's notation was misprinted and suggested "queen on color" as a more reliable guide.

While playing, I noticed a few people looking at my poster. The poster itself was text heavy. The text was small--12 and 14 point mostly. I included four chess diagrams connected to problems.

Yesterday's Chess Skills post was something I created for the poster. I also had:

White checkmates in two moves (three solutions)

White checkmates in ten moves (twenty-two optimal first moves)

Black checkmates in six moves (one solution)

My poster claimed chess has implications for science, math, and computing. First Move identifies other areas of the curriculum as well, such as reading.

I offered a few bullet points relating to math and computing, as well as a short statement concerning the science of memory.
Scientists who study human memory often study chess players. They have learned that eidetic memory (photographic memory) is of minimal value for chess players, but that pattern recognition is a strength of chess masters. World Champion Magnus Carlsen claims to remember the ideas (patterns) from 10,000 complete games that he has studied. 
Much of education psychology (what teachers must learn to learn to teach) is rooted in work that grew out of study of chess players.
Several bullets concerning math and computing highlighted tablebases.
Solving Chess
Every possible position with seven or fewer pieces have been solved by computers. These solutions are stored in files called tablebases.
1980s Three and four piece tablebases
1990s Five piece tablebases
2005 Six piece tablebases
2012 Seven piece 
Eight piece tablebases may be many years away. 
Tablebase Storage Problems
3-4 piece require 30 Megabytes
5 piece require 7.05 Gigabytes
6 piece require 1.2 Terabytes
7 piece require 140 Terabytes
If you were designing a poster for an elementary science fair or similar public presentation, what would you highlight?

27 March 2014

A Knight Problem

Solve This

A knight standing on a center square (e4, e5, d4, d5) has eight different squares it can move to in one move. How many can it reach on the second move?

26 March 2014

Lesson of the Week

Creating Checkmates

In this week's chess clubs, young players create checkmates that fulfill specified conditions on cards drawn at random. There are eighteen different cards. The deck contains as many as six of each card, but some in less quantity. I suspect that the original deck had card that are now missing.

These were left behind by a coach who preceded me at one of the schools. I would like to know their origins.

Some samples:

Create a checkmate using:
White: King and Queen
Black: King
Create three different mating patterns.

Naturally, I hope some team of children will create:

Create a checkmate using:
White: King and two Bishops
Black: King
Create mates both in and out of the corner.

Create a checkmate using:
White: King and Knight
Black: King and Rook
Create mates for both sides.
Do the kings have to be in the corners?

Create a checkmate using:
White: Kc3, Qg4, and Bg1
Place the Black King on a square where it is:
a) Checkmate
b) Stalemate
c) White to move and mate in one.

24 March 2014

Hidden Threats

Taking issue with Emanuel Lasker's assertion that combinations are rare, Yasser Seirawan asserts:
Combinations of some sort can be found in the majority of master games, sometimes in the moves actually played and often in the variations hidden behind those moves.
Yasser Seirawan, with Jeremy Silman, Winning Chess Tactics (2003), 5.
Seirawan's assertion may be illustrated in a position from last year's European Individual Championship. Erwin L'Ami, playing the Black side of a French Tarrasch where queens were exchanged early, stepped his king towards the middle. This move seems to have left a pawn undefended, but it is well protected by a threatened combination.

White to move
After 21...Kf7

Had White taken the h-pawn, Black would have responded with 22...g6. The effort to rescue the trapped bishop with 23.Nf4 leads to a double attack. 23...Kg7 attacks the knight with a discovery while the king threatens the bishop directly. After 24.Nxg6 Rfe8, Black gains the bishop for two pawns and there remains the additional latent threat of Nxd4 followed by Ne2+ forking king and rook.

Hence, White's best choice after 23...Kg7 seems to be 24.Rxc6 Rxc6, and then 25.Nxg6 Rfc8 26.Ne7 Kxh7.

White to move

After the White knight captures one of the rooks, Black will have a bishop and pawn for three pawns--a clear advantage. Wisely, Pawel Jaracz played 22.Rfd1 and the game was eventually drawn after many moves.

20 March 2014

Progressive Tactics

Lesson of the Week

Last week's progressive tactics featured checkmate in one move, then two and three move checkmates leading to the same positions and one checkmate in four. This week's series of problems concern the gain of material. At the minimum, the player to move will gain a minor piece for a pawn. As before, those requiring two and three moves lead to the sae positions as those requiring one move.

Building progressively from one move actions to those requiring several moves will develop the students chess vision and imagination.

White in one
(White to move, gains material with one move)

Black in one

White in one

White in one

White in one

Black in one

White in two

Black in two

White in two

White in two

White in three

Black in three

19 March 2014

Beware Stalemate

If a player has no legal moves and is not in check, the game is drawn by stalemate. The side with greater force is robbed of victory. Players under time pressure and beginners are particularly prone to this fate. The positions below are all from recent online play.

White to move

White played 65.g6 and was subjected to a series of checks that ended in stalemate.

White to move

Nearly every move wins except 55.Kf6, which was played in the game.

White to move

64.Qg3# ends Black's charade, but instead White played 64.Bxf3.

White to move

Here also, White played Qc3 instead of the simple Qa1#.

White to move

That White played 41.Rxg2 justifies Black's decision to play on in a hopeless position.

White to move

White's king needs to head towards d7 to free Black's king from a trap. Instead, White played 56.Kh7 and gave Black a choice of drawing moves.

Sometimes the weaker side can trap the stronger.

Black to move

53...Kf6 kept the White king stuck in front of its pawn.

18 March 2014


In the so-called Lucena rook ending, the defending player runs out of checks. In this position, White failed to comprehend the importance of his own pawns.

White to move

White played 46.Rc8+ and resigned after 46...Kd4 47.Kf2 d1Q 48.Rd8+ Rd5 0-1.

Convinced that White had resources in the position, I tried 46.Kf2 against Hiarcs. I reached a position that I thought should be drawn after 46...Rf8 47.Rd7 Rf7 48.Rd8 Rc7.

White to move

I played 49.f4 and managed to get my king far enough advanced that I gave up the h-pawn without worries. The engine underpromoted to a rook on d1 as it was clear that I would capture either rook or queen.

12 March 2014

Mating Net

This position arises in the annotations to Nunn -- Korchnoi, Luzerne 1985 (Chess Informant 40/360). In the game itself, Nunn refused Korchnoi's offer of a bishop on a4. This position is one of several that might have arisen if he had taken the bishop.

Black to move

Korchnoi offers the interesting line leading to checkmate: 30...Rxd3 31. Rxd3 Nb6+ 32.Ka5 Nc4+ 33.Ka4 b5#.

In the game itself, Nunn resigned after Black's move 34.

11 March 2014

Progressive Tactics

Lesson of the Week

Start with checkmate in one, then find two move checkmates, then three and four moves. The longer problems are from the same games as the one move problems. The player to move and the number are indicated above each problem.

1. Black in one

2. White in one

3. Black in one

4. Black in one

5. Black in one

6. White in one

7. Black in two

8. White in two

9. Black in two

10. Black in three

11. White in three

12. White in four

10 March 2014

Checkmate Patterns

My conviction is growing that beginning chess players should work through large numbers of chess problems where they find checkmate in one move. Such problems develop pattern recognition that facilitates the imagination during play.

Several years ago, I created a set of forty-eight checkmate in one problems from games that I found in several databases. Recently, I have been using these sets of problems with young chess players. No answer key should be necessary as verifying the solution is as easy as ABC. Can the defending king avoid the check? Can a piece step in the way and block the check? Can the checking piece be captured?

Below are the first six problems. White moves in each.