30 November 2006

The Importance of Small Differences

Continuing with Lasker's Moves that Matter, the diagram shows a position that did *not* occur in the famous first game of the 1907 Marshall - Lasker World Championship match.

The diagram is the position after 1.e4 e5 2.Nf3 Nc6 3.Bb5 a6 4.Ba4 Nf6 5.O-O Be7 6.d4 exd4 7.e5 Ne4 8.Nxd4 O-O 9.Nf5 d5 10.Bxc6 bxc6 11.Nxe7+ Qxe7. Soltis pointed out that it is similar to the Marshall - Lasker game, which opened 1.e4 e5 2.Nf3 Nc6 3.Bb5 Nf6 4.d4 exd4 5.O-O Be7 6.e5 Ne4 7.Nxd4 O-O 8.Nf5 d5 9.Bxc6 bxc6 10.Nxe7+ Qxe7. The only difference is the Pawn on a6, which was on a7 in the Lasker game.

(Not the)
World Championship Match (g.1)
New York 1907

Lasker, Emanuel

Marshall, Frank
(After 11.Qd8-e7(xN))
[FEN "r1b2rk1/2p1qppp/p1p5/3pP3/4n3/8/PPP2PPP/RNBQ1RK1 w - - 0 10"]

Soltis also mentioned that many annotators of the game assumed that White already had a bad game, although 'The position is nothing more than a transposition to a standard Lopez variation. The only difference is the addition of ...a6 to a position recognized today as just equal.'

Isn't the position of the Pawn on a6, which is on the same color as Black's remaining Bishop, the difference between an equal position and a a position which is slightly better for Black? The development Bc8-a6 is excluded in all variations. I have seen other positions where the advance of an a-Pawn or an h-Pawn from its second rank to its third is the difference between a good game and a not-so-good game. Perhaps the diagram is another example.

28 November 2006

Blogger Beta: 'Upgrade Your Template'

Today is another maintenance post. I chose the option to upgrade my template, selected the same look that I had previously, and checked the results. After reorganizing the sidebar to have the elements in the same order, I added RSS feeds from About Chess at the end.

The archive list in the new template is a big improvement. It shows the count of posts in each month and has a button on each list to expand it in place. This will make it a lot easier for me to look at all chess blogs once a month. Thank you Blogger.com!

26 November 2006

When Is a Game or a Position a Foregone Conclusion?

Continuing with Lasker's Moves that Matter, the diagram shows the continuation of Evans Gambit: Chigorin - Lasker, St Petersburg 1895. The first post has a link to the complete game on Chessgames.com.

There are two types of flaws in analysis that annoy me. One is assuming that the result of a game is a foregone conclusion before it is played. For example, when Chigorin played Lasker, the German master won because he was the better player. The other is assuming that a position leads to a foregone conclusion because it is obvious. For example, Lasker won from the diagrammed position, and there was nothing Chigorin could do to change the result.

St Petersburg 1895
Lasker, Emanuel

Chigorin, Mikhail
(After 11.Bb6-a7)
[FEN "r1bqk2r/b1p2ppp/p1pp1n2/P3p3/3PP3/2P2N2/5PPP/RNBQ1RK1 w kq - 0 12"]

The game continued 12.dxe5 Nxe4 13.Qe2. After White's 13th move, the game was lost. Would 12.Qa4 have drawn? What about 13.exd6? At what point was White's game irretrievably lost?

24 November 2006

Using ShredderBase

In the October 2006 Chess Life, GM Pal Benko's column 'Endgame Lab' discusses 'Computers and Endgames'. Benko gives a number of 5 and 6 piece endgames which he analyzed using tablebases. I need practice using this technique, so I checked his analysis using...

Shredder Computer Chess : Endgame Database
http://www.shredderchess.com/online-chess/online-databases/endgame-database.html

...Everything checked well except Benko's third position, shown in the diagram.


White to play and win
[FEN "8/7n/2K3kP/4P3/8/8/8/6N1 w - - 0 1"]

Benko gave 1.e6, which ShredderBase (SB) confirms as a 'Win in 29'. Now Benko continued 1...Kxh6, although SB says that 1...Kf6 loses slower. After 2.e7 Nf6 3.Kd6 Kg7 4.Ke6 Kg6 5.Ne2, Benko said, 'The computer pointed out 5.Nf3 is quicker'. SB says that both 5.Ne2 and 5.Nf3 'Win in 21.'

This is not an earth shattering disagreement, but I thought it curious that even people using computers can differ on optimum sequences. How long will it take to produce 7-piece tablebases?

22 November 2006

Evans Gambit: Chigorin - Lasker, St Petersburg 1895

After digressing for a few days longer than expected to make the switch to Blogger Beta, I'm raring to return to Lasker's Moves that Matter. The next game, Chigorin - Lasker, St Petersburg 1895, saw a theoretically important novelty in the Evans Gambit.

In his introduction, Kasparov (KAS) made an interesting point:

Lasker had an indifferent attitude to the study of opening theory, considering that the main thing was to achieve playable positions. Even so, he devised at least two defences that bear his name: in the Queen's Gambit (cf. his match with Marshall, 1907) and in the Evans Gambit -- here his defensive plan put the "opening of the 19th century" out of action for almost 100 years!'

The Lasker Defense to the Queen's Gambit starts 1.d4 d5 2.c4 e6 3.Nc3 Nf6 4.Bg5 Be7 5.e3. Now Lasker played 5...Ne4 three times -- games 3, 5, and 15 (the last) -- in his 1907 title match with Marshall.

The Lasker Defense to the Evans Gambit is 1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.b4 Bxb4 5.c3 Bc5 (5...Ba5 is more common, but transposes to the game continuation) 6.O-O (KAS: 6.d4!) 6...d6 7.d4 Bb6. The position is shown in the diagram.

St Petersburg 1895
Lasker, Emanuel

Chigorin, Mikhail
(After 7...Bc5-b6)
[FEN "r1bqk1nr/ppp2ppp/1bnp4/4p3/2BPP3/2P2N2/P4PPP/RNBQ1RK1 w kq - 0 8"]

Now Chigorin (Kasparov's preferred spelling; Soltis [SOL] prefers 'Tchigorin') continued 8.a4.

KAS: 'Alas, Chigorin avoids the current 8.dxe5 dxe5! with two possible continuations:
  • 9.Qxd8+ Nxd8 10.Nxe5 Be6 and in view of the weakness of White's Queenside Pawns, Black has a favorable endgame (Chigorin - Pillsbury, London 1899).'

  • 9.Qb3 Qf6 [I'm omitting the side variations in the published analysis] 10.Bg5 Qg6 11.Bd5 Nge7 12.Bxe7 Kxe7 13.Bxc6 Qxc6 14.Nxe5 Qe6 15.Nc4. Regarding this, the main variation of the defence, the two players conducted a lively dispute on the pages of the magazines they edited. Chigorin believed in White's attacking resources, whereas Lasker considered that Black's two Bishops and the absence of any weaknesses in his position promised him the advantage -- for example, after 15...Rd8 16.Qa3+ Ke8'.

  • KAS also gave variations to show that 9.Nbd2 and 9.Bxf7+ are inferior.
SOL: 'On 8.dxe5 [Lasker] intended 8...dxe5! so that 9.Qxd8+ Nxd8 10.Nxe5 Be6 reaches a favorable endgame. Chigorin didn't believe it was favorable and lost the ending to Pillsbury at London 1899 -- a loss that was regarded as the death blow to the Evans until 9.Qb3! was found.

Reinfeld/Fine, referring to the choice between 8.dxe5 and 8.a4: 'White to be sure could regain his Pawn by 8.dxe5 dxe5 9.Qxd8+ Kxd8 10.Nxe5 Be6, but his Queenside Pawns would be weak and his game undeveloped. Here we see the main strength of Lasker's Defense: when White adopts the Evans Gambit, he wants to play an "immortal" game; instead he is confronted with the unpleasant alternative of (1) turning into a dry ending in which he has to work hard to stave off defeat, or (2) giving up the Pawn for a slight semblance of an attack that can be parried with ease.'

After 8.a4, Lasker continued 8...Nf6. There is a lot more play in this position and I'll look at the game again in another post.

It's possible I'm misunderstanding something, but there seems to be a contradiction between KAS and SOL. KAS says that 'the two players conducted a lively dispute' on the merits of 9.Qb3. SOL says that Lasker's line 'was regarded as the death blow to the Evans until 9.Qb3! was found'. KAS also says that Lasker's 'defensive plan put the "opening of the 19th century" out of action for almost 100 years'. Did it take 100 years for the chess world to appreciate the dispute on the pages of Lasker's and Chigorin's magazines?

To play through the complete game see...

Mikhail Chigorin vs Emanuel Lasker, St Petersburg 1895
http://www.chessgames.com/perl/chessgame?gid=1036422

...on Chessgames.com.

20 November 2006

101st post: Switched to Blogger Beta

'Want to switch? Three things you need to know:
- You’ll need a Google Account
- Third-party applications need to update
- You can’t “undo”'

A few useful(?) links...

More about Google Accounts
http://www.google.com/support/accounts

FAQ
http://help.blogger.com/bin/topic.py?topic=8939

Terms of Service
http://beta.blogger.com/terms.g

...EOM.

18 November 2006

100th post: What happened to the switch to Blogger Beta?

For the last week or so, each time I signed into Blogger.com I was given the option to switch to the Blogger Beta version. The first page(s) warned me that this would involve switching my Blogger account to my Google account, or something like that. Since I was pressed for time all week I decided to wait until the weekend, make the switch, and test everything out on my 100th post. Today is Saturday, but I'm no longer getting the option to switch.

So here is the 100th post on Chess for All Ages. Now what am I going to do?