One for Nunn

"John Nunn's Chess Puzzle Book" by John Nunn, 1999 Gambit
Publications, Figurine Algebraic Notation, Softcover, 208pp.,
$19.95

As the title implies, "John Nunn's Chess Puzzle Book" consists
mostly of chess puzzles; it essentially falls into the broader
category of quiz books. In the Introduction, Nunn classifies such
books into four types: basic chess exercises, entertainment, self-
evaluation and instructional. We would suggest that most recent
quiz books would probably fall into a combination of the last two:
instructional and self-assessment/evaluation. According to Nunn,
he "decided to combine the aims of entertainment, self-assessment
and instruction, but with the emphasis on the last of these." 

There are eight chapters in the book, plus a brief Introduction, a
Score Table and a "Test score to ELO points conversion table".
The 250 total quiz positions are divided into five chapters: (1)
Puzzles 1, the largest chapter with 80 positions; (2) Find the
Wrong Move, which is exactly what the titles indicates, 13
positions; (3) Puzzles 2, 79 positions; (4) The Test of Time, a look
at 30 positions from the 1911 Karlsbad tournament; and (5) Test
Positions, consisting of 8 groups of 6 problems each. In addition,
Nunn includes a chapter of "Hints" applicable to all but the Test
Positions, Solutions to Puzzles, and Solutions to Test Positions.

One of the features that differentiates this work from other quiz
books is the "Test of Time" chapter. Named after Kasparov's book
in which he analyzes early games from his own career, Nunn takes
a look at games from a present day invitational GM tournament,
1993 Biel Interzonal, and compares the quality of play to an
invitational event of approximate strength from a previous era,
Karlsbad 1911. Nunn writes that his "main interest is in assessing
how much the overall level of chess has changed since the pre-
First World War period" (page 67).

His methodology of comparing the games consisted of using the
computer software "Fritz 5" to check each game in both
tournaments (about 800 total games) for obvious blunders. Nunn
then reviewed the findings, one blunder at a time. What he found
was somewhat surprising: "the old players were much worse than I
expected. The blunders thrown up by Fritz were so awful that I
looked at a considerable number of complete games 'by hand',
wondering if the Fritz results really reflected the general standard
of play. They did" (page 68). At the end of the chapter, he includes
30 problems from Karlsbad, most of about moderate difficulty,
comparable to the problems found in the rest of the book.

Biel, however, is barely addressed, other than mention that
positions of interest have been dispersed throughout the book.

Although the background narrative to this chapter was interesting
(and might even be a good subject for a dedicated publication), it
strikes us as being of questionable relevance to the main theme of
this book, which is instructional quiz positions. Does the potential
purchaser of this book really care that Hugo Sichting, one of the
participants at 1911 Karlsbad, played at about Elo 2100 level
during this tournament (for reference purposes, Gaige puts
Suchting's historical Elo rating at 2450) and that he made some
laughable blunders? Probably not, since the buyer probably isn't
interested in this book for its examination of the 1911 Karlsbad
games.

On the other hand, when Nunn sticks to his main theme of quiz
positions, this becomes a very desirable work. One of the more
appealing aspects is Nunn's presentation of the puzzles. Positions
are provided in random order, not grouped by type of combination
or some other organized method that facilitates finding the
solution. Should the reader desire a hint, such are made available
in a separate chapter for all positions except the test problems. This
approach, at least in our opinion, makes good sense if the intent is
to use the quizzes as a learning tool. In Nunn's words, "When you
are playing a game, you do not know whether there is a
combination and what it might involve. In this book I cannot
disguise the fact that there is 'something' in the position, but I do
not see why the challenge should be made even more artificial by
giving away further information" (page 5).

Another aspect that makes a favorable impression is Nunn's de-
emphasis of time as a critical factor in solving puzzles. Too many
quiz books place a premium on solving as many problems as
possible in the shortest period of time, meaning that the reader is
often forced to make hasty decisions about positions that have
been misanalyzed by grandmasters (who may have considerably
more time across the board than the reader is allotted in the book!)
Nunn writes in the narrative preceding the "Test Positions" chapter
that "there is no specific time-limit for the tests; you should
continue until you feel you have reached your limit in each
position. However, a guideline time would be between one and
two hours for each test" (page 87). Let's remember why we
purchase quiz books: in many cases, it is to learn and improve our
game, not to beat the clock. One of the best ways to improve one's
analytical skill is to practice performing as thorough analyses of
positions as possible. At least initially, arguably, time should not
be a significant consideration.

Further kudos to Nunn for using only positions from real games
and not including those concocted configurations of pieces that
make one wonder how they could possibly have occurred in a
game. Sadly, such surreal positions are all too common in puzzle
books.

Nunn also mentions that he has "carefully computer-checked all
the positions in this book" for alternative solutions and to ensure
accuracy. We decided to take a look at how our copy of Rebel 10
computer software would assess some of the trickier test positions.
First, however, the test had to be taken.

Without the specter of Father Time hanging over one's head,
taking Nunn's test of 48 problems, segregated into 8 parts of 6
positions, proved to be a relatively painless and stress-free
experience. Although Nunn suggests a "guideline" of one to two
hours per six puzzles, we averaged only about five minutes or less
on each position (with a few notable exceptions). Nunn also
recommends setting up the positions on a board, but again we
decided to go our own way and work on board visualization skills
by solving only from the puzzle diagrams. While our final score
was commensurate with our 2100+ US Chess Federation rating,
had Nunn's directions been followed, the score would have been
higher, since a board and set obviously facilitates much more
accurate analysis compared to mental visualization. 

Well before the test chapter was reached, it was apparent that
depth would be key to arriving at correct solutions to the practice
puzzles, as well. Let's start with the first problem in the book,
position #1 of Puzzles 1, from the game Piket-McShane, 1996/7
Bundesliga. (See Diagram)

White: Kh1, Qb3, Re1, Rc3, Bb2, Ne4; pawns - b5, d5, d6, f3, g3,
h2 
Black: Kg8, Qg6, Rf8, Rf7, Bf5, Bh6; pawns - b7, c7, e5, h5

With Black to play, McShane chose ...cxd6 and the game
eventually was drawn. Nunn's question is "How could he have won
brilliantly?" (page 7) Realizing that most problems contain a
tactical solution probably based on "some spectacular element" in
Nunn's words, we immediately examined 1...Bxe4 2 fxe4 Qxe4 3
Rxe4 Rf1+ 4 Kg2 R8f2+ 5 Kh3, but couldn't "see" anything
further for Black, at this point. Of course, had the position been set
up on a board, it wouldn't have been too much of a chore to find
5...Rh1!, justifying the Black Queen sacrifice.

As mentioned earlier, we checked some of the solutions to the test
questions to confirm Nunn's claim of accuracy. One of the more
fascinating positions is #246, which is analysis from the game
Ljubojevic-Andersson, 1976 Wijk aan Zee. White is to move. (See
Diagram)

White: Kg1, Qf4, Rf1, Rd1, Be2, Be3, Nf6; pawns - a2, b2, c2, g2,
h2 
Black: Kh8, Qc5, Ra8, Rf8, Be7, Be6, Ng6; pawns - a6, b7, f7, g7,
h7

The first thing one notices is that both Queens are under attack by
minor pieces, with the White Queen being hit twice. In addition,
White's knight is being attacked by a pawn on f6. This was one of
those problems where we expended considerably more than a few
minutes, to no avail. On the other hand, it took Rebel 10 all of 6
seconds to find the startlingly response of 1 Qg3!!, winning the
exchange after 1...gxf6 2 Bxc5 Bxg3 3 Bxf8 Nxf8 4 hxg3.

Another interesting middlegame position is #235, from Benjamin-
Kozul, 1997 World Team Championship. (See Diagram)

White: Kb1, Qf3, Rd1, Rd3, Bc2, Nh5; pawns - a2, b3, c3, e4, f5,
g4, h4 
Black: Ke7, Qc5, Rc7, Rc8, Ba8, Bf4; pawns - a3, b5, d6, e5, f6,
f7, h6

Black to move. This solution, another Queen sacrifice, took Rebel
10 about 2 minutes to find: 1...Qxc3!! 2 Raxc3 Rxc3 3 Qf1 Rxc2 4
Nxf4 Rb2+ 5 Ka1 Rcc2 and Black wins.

So as to not incorrectly give the reader the perception that most of
the test problems are nothing more than spectacular sacrifices, here
is position #237 from Timman-Nunn, 1982 Wijk aan Zee. (See
Diagram)

White: Kb2, Rd3; pawn - c2 
Black: Kb4, Qe4; pawn - a4

White is on the move and undoubtedly trying to split the point.
Despite the small number of pieces, the position is deceptively
difficult. After about 20 minutes of analysis, we decided on 1 Ka2,
which loses to 1...a3! after a long Queen vs. Rook ending,
according to Nunn. We were somewhat consoled, however, when
Rebel came up with the same solution, 1 Ka2, also missing 1...a3!
in its analysis. The correct answer? 1 Ra3!, when Black can't make
progress after 1...Qe5+2 Ka2. Nunn comments "White should keep
his king on b2 except when checked, and otherwise keep his rook
posted on a3 or d3" (page 202).

"John Nunn's Chess Puzzle Book" is another excellent, recent
work by Gambit Publications. Unlike many quiz books that
contain problems based upon tricks in positions, Nunn has
primarily selected positions that require precisely calculated
solutions. By virtually eliminating time as a factor and
encouraging the use of a set and board, Nunn's problems take on a
pragmatic value as aids to improving one's ability to calculate and
analyze correctly.

This is a very good book, recommended not only for its interesting
problems but for its instructional value, as well. If more quiz books
were as good as this one, well, there probably wouldn't be a need
for any more quiz books.