Peter Joseph
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Your opponent is not Karpov


To win at chess you must be alert! 


You must notice things.  Look across the table at your opponent.   The first thing to notice is that your opponent is neither Kasparov nor Karpov.   This means you can be absolutely sure your opponent will make mistakes during the game.   Your job is to stay alert, recognize when he makes a mistake and punish him for it.  There are two kinds of mistakes he can make: tactical mistakes and strategic mistakes.  Tactical mistakes are errors that you can punish in a few moves.  Strategic mistakes are ones that might take you many moves to punish.   In this book we will concentrate on tactical mistakes.   After all, some authorities claim that chess is 90% tactics.


The first few moves your opponent makes are most likely ones that he got from an opening book, so they are probably not mistakes.   However, eventually he will deviate from the book and then he will likely make a mistake.   He may make 10 or 20 or even 30 moves before he makes a tactical mistake.   But you must stay alert, recognize when the mistake occurs and jump on it.


But how are you to know when a mistake occurs?   There are certain arrangements of your opponent's pieces that are mistakes - certain patterns.   These arrangements or patterns are called motifs.   This book will help you to recognize them.  


After you recognize the motif, you must try to punish your opponent for his mistake.   If your opponent blunders badly enough, he may place a piece unprotected where you can take it.  He has "hung" a piece.   You punish him in one move.   Most of the time his mistakes are more subtle.  It may take several moves to punish him.   These several moves are called a combination.  To make a combination, you must know various tricks or techniques such as pin, skewer, double attack etc.   These techniques are called the theme of the combination in many books.   Most books on tactics are organized by combinational theme.   This book is organized by motif.  I think this is more logical.  


You cannot defeat your opponent until he makes a mistake.   Don't worry.   He isn't Karpov.  He will make a mistake.   But first you must recognize that he made a mistake before you go looking wildly around for pins and skewers.

Chapter 1

Tactical Inventory


The first step in recognizing when your opponent has made a mistake is to take what my former teacher. Jonathan Yedidia, calls a "tactical inventory".   Before you decide on what move to make, look at each of your opponents pieces and pawns.   Are any of them undefended?   If they are they are a potential target.   We will call such a piece a loose piece.   If you attack a loose piece, your opponent must defend it or move it or do something else to prevent you from capturing it.


If there are 2 loose pieces (or pawns), can you attack both with one move?   If you can, then your opponent may have a hard time defending both pieces at once.   Consider Figure 1-1


Fig. 1_1

Black's two knights are loose.   White plays Rb5, attacking both knights at once.   Since black has no move that defends both knights, white wins a piece.   Notice that if the knight on b7 had been on b6, then Black would have the defense N6d5 protecting both knights with one move.   Just because the motif is there doesn't mean the combination will be successful.   But the motif signals that there is a chance of a combination that we should examine.


The above example is too easy.   You should be able to find the correct move without a tactical inventory.   That is because there were only a few pieces on the board and therefore you knew where to look.   Before we try a harder example, let us extend our tactical inventory.   Consider pieces or pawns that are attacked once and defended once.   These are also loose.   If you attack such a piece again, it will be attacked more often than it is defended and you opponent will have to take steps to prevent you from capturing it.   Another method is to capture the piece that is defended once.   Your opponent recaptures.  The piece he recaptured with is now undefended.


The next diagram is figure 191 from the book "1001 Winning Chess Sacrifices and Combinations" by Reinfeld.  Perform a tactical inventory.   The rook on a8 is undefended.  The pawn on h7 is defended once by the king and attacked once by white's bishop.   The bishop on e7 is also defended once and attacked once.

So our targets are: the rook on a8, the bishop on e7 and the pawn on h7.   We now need a move that adds an attacker to 2 of our targets at once.   For some people that is a sufficient hint to find the winning move


Fig. 1_2

If you didn't find the winning move, don't worry.   We can find it by the method of crossroads.   Let us look for the ways we can attack the various targets.  The rook on a8 is well hidden behind black's pawns and there is no easy way to attack it so let us turn our attention to the other 2 targets.   The bishop can be attacked along the vertical e file.  It might also be possible to attack it along the dark diagonals leading to e7 but that is unlikely to be profitable bcause the bishop could capture any piece that tries to attack it along the diagonal.   So the only practical road to attack the bishop is along the vertical e file.


How about the pawn on h7.  It can be attacked along the vertical h file, but the vertical h file doesn't cross the vertical e file.  There is no crossroads.   The h7 pawn can also be attacked along the light diagonal leading to h7.  As shown in the next diagram, the diagonal road to h7 and the vertical road to e7 cross at e4.   We need to move apiece to e4 that can attack on both the diagonal and the vertical.  The only such piece is the queen and yes the queen can move to e4.


So the winning move is 1.Qe4.  White is threatening to take at h7 which does more than win a pawn.  It is mate.  So black must defend against the mate by for example 1. ---  g6 2.Qxe7 Qxe7 3.Rxe7  and white has won a bishop for free.

Fig 1_2A

Note that there are other ways that white could play this.  He could first capture the h7 pawn with his bishop.  1. Bxh7+ Kxh7 2.Qe4+ Kg8 3.Qxe7 regaining the bishop.  This way white wins a pawn.  Not as good as free bishop.


Alternatively he coud start by capturing the bishop.  1.Rxe7 Qxe7 2.Qe4 Qxe4 3.Bxe4  This time white has lost the exchange.   So the first way of doing things is best but it is worth looking at these alternate move orders.  Sometimes one of them may be better.


Notice that it didn't take any genius to find the winning move.  Just a little work   Tactical inventory and the method of crossroads.

If you want to see more of this stuff, send me an email and I will send the rest to you.

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