Right from the start of the game the chess pieces will move around in a shared space (the 64 squares on the chessboard). Naturally, as the game develop, these movements will cause the pieces and pawns to interact with one another (and with the squares on the board) in various ways.
In this lesson you will discover why learning to observe and understand these interactions should be a very important part of your tactical training, and why it is the first lesson in the chess tactics training room. (All the other lessons will in some why rely on your understanding of these interactions.)
Types of Interaction Between Chess Pieces
There are primarily 4 types of interaction between the pieces and pawns:
These interactions are best explained by examples. (The diagrams and comments below will clarify it. Looking at these examples is in itself a good exercise.
“Attacking” simply refers to the fact that a piece can capture an enemy piece on the next move. This does not mean that you will capture the piece, of course, or that it is even a good idea to do so, but you must be aware of this interaction. We will use the position in the diagram below (white to move) to give examples:
- The white bishop on c4 attacks the black pawn on f7.
- The white bishop on e3 attacks the black pawn on a7.
- The black queen on a5 attacks the white pawn on a3 and the white knight on c3.
- The black bishop on g7 attacks the white knight on c3.
- The black knight on g4 attacks the white bishop on e3 and the white pawn on h2.
Important vs Unimportant Interactions
Some of the observed interactions will be practically unimportant and you will discard them quickly. However, the interactions you discard may be more significant than you initially realized.
Example: In the diagram below you may quickly discard that the black queen can capture the white pawn on a3 because it is defended…
…however, if the white pawn on b2 moves, then the pawn on a3 will be hanging–and this is, in fact, a useful observation.
The lesson here is that you should observe all possible interactions, regardless of whether they appear important, or not. If you skip this step you will miss out on exciting tactical opportunities!
Many of the interactions presented on this page may seem elementary to an amateur. But in the eyes of a master they are the key to all the tactics that hide in the position. Learning to observe these interactions will have an immediate effect on your tactical skill, for the better.
A piece that supports another piece is known as a “defender”. For example:
- The white queen on e1 defends the white knight on c3 and the bishop on e3.
- The white rook on f1 defends the white pawn on f4 and the queen on e1.
- The white bishop on e3 defends the white pawn on f4.
- The white king on g1 defends the white pawn on h2.
- The black bishop on c8 defends the black knight on g4.
- The black rook on a8 defends the black pawn on a7 and bishop on c8.
- The black king on g8 defends the black pawn on f7.
Due to its important role, a defender can in itself become vulnerable to tactical ideas, particularly to tactics that involve removing that defender in some way.
A piece or pawn controls a square if it could potentially capture an enemy piece moving to that square. Here’s a few examples:
- The white pawn on a3 controls the b4-square.
- The white pawn on f4 controls the g5-square and e5-square.
- The white knight on c3 controls the a4-square and the e4-square.
- The white bishop on e3 control the c5-square and the d2-square.
- The black pawn on c6 controls the b5-square and d5-square.
- The black rook on d8 controls some squares on the d-file.
- The black queen on a5 control some squares on the 5th rank.
Not all control is absolute
Obviously, attacking a square does not mean you have absolute control over that square. In most cases both sides will be fighting for control over certain squares and every piece that attacks that square will add to your control of it. Note however that, due to their relative low value, pawns usually play a more significant role in controlling squares.
Obstructing is when a piece or pawn obstructs the movement of another piece or pawn by occupying a square in its way.
Obstructing a piece can work favorably (the pawns in front of your king protects him by obstructing enemy pieces) or unfavorably (the mobility of a piece can be limited because other pieces obstructs it). For example:
- The white pawn on b2 obstructs the white rook on b1’s view of the b-file.
- The white knight on c3 obstructs the black queen’s view of the d2-square and the e1-square and similarly obstructs the view of the white queen on e1.
- The white bishop on e3 obstructs the white queen on e1’s view of the e-file, particularly of the undefended pawn on e7.
- The white pawn on f4 obstructs the white rook on f1’s view of squares on the f-file beyond the 4th rank, particularly of the f7-square.
- The white pawn on f4 also obstructs the view of the white bishop on e3’s view of the g5-square and the h6-square.
- The black pawn on f7 obstructs the white bishop on c4’s view of the black king on g8.
- The black knight on g4 obstructs the black bishop on c8’s view of the h3-square.
Now that you’ve seen examples of the 4 primary types of interaction between the pieces, pawns and squares, let’s take this to the next level!
The Consequences of Moving a Piece
Every move on the chessboard has consequences. Why is it important to continually observe these consequences? Because your tactical awareness depends on it! Now you may be asking: “But there are so many interactions on the board, how could I possibly keep track of it all?”
Here’s a very helpful technique:
There is no need to restart your observations on every move. Instead, you can simply focus your attention on the consequences of the last move.
You should do this right from the start of the game! For example, what are the consequences of white’s first move in the diagram below?
The immediate consequences of white’s first move is that it:
- clears the white queen’s view of the d1-h5 diagonal,
- clears the white bishop on f1’s view of the f1-a6 diagonal,
- gives up its control of the f3-square and d3-square,
- gives up its future control of the f4-square and d4-square,
- gains some control over the f5-square and the d5-square,
- obstructs the diagonals that pass through the e4-square (this last observation is particularly relevant to the development of the bishops).
For the rest of the game then, you should similarly observe the consequences of every new move in the position.
To help you on your way, let’s consider a few more moves in the position we already know. In the diagram below, what are the consequences of white’s move 1.b4?
Hint: The consequences of a move usually consist of 1) what it does and 2) what it doesn’t do anymore. Its a useful habit to first consider what it doesn’t do anymore.
- The white pawn on a3 is now undefended.
- The white knight on c3 now has one less defender.
- The white pawn on b4 attacks the black queen on a5.
- The white pawn on b4 now controls the c5-square.
After 1.b4, black didn’t feel comfortable to play 1… Qxa3 since white could play 2.Rb3 and it’s not quite clear how black will respond. Either way, black found a better way to continue and played 1… Qh5! What are the consequences of black’s move?
Here’s the consequences you should observe:
- The white pawn on a3 is not under attack anymore.
- By moving their queen, black cleared the a5-square–which implies black could potentially play a7-a5 later on.
- The black rook on d8 is now undefended. (This is not an immediate problem for black because white can’t effectively attack the rook.)
- The black queen attacks the white pawn on h2. In fact, black is threatening to play Qxh2# (this consequence will obviously take priority!) Since black is threatening checkmate, white can only consider moves that remove this threat.
- The black queen gives additional support to the knight on g4.
What are the consequences of white’s next move, 2.h3?
- By moving the white pawn to h3, it gives up control over the g3-square. Even though black can’t take advantage of this fact right away it is still a good habit to recognize this consequence.
- The white pawn on h3 obstructs the black queen’s view of the h2-square, protecting the white king against the checkmate threat.
- The white pawn on h3 attacks the black knight on g4.
Black captures the white bishop on e3 with the knight, 2… Nxe3. What are the consequences of this move?
Black’s move, 2… Nxe3:
- gives up control of the h2-square and the f2-square.
- removes the attacker of the black pawn on a7.
- clears the g4-square, which opens the view of the black queen on h5 and of the black bishop on c8.
- attacks the white rook on f1.
- attacks the pawn on c2 and the pawn on g2.
- attacks the bishop on c4.
- removes an important defender of the white king on the dark squares.
- draws the white queen to the e3-square where it will become a new target for black’s pieces.
White plays 3.Qxe3. This move is maybe not the best but other moves aren’t much better. Either way, white is losing material due to the tactical combinations in the position.
White’s move, 3.Qxe3, has these consequences:
- The queen still defends the knight on c3, but from a new position.
- The white queen gives up control of the h4-square.
- The new geometric relation between the white queen and white king (pieces on the same diagonal) allow black to employ a pin tactic.
- The queen attacks the pawn on a7, but this doesn’t matter because the rook on a8 defends it. In any case, there are other matters in the position that are much more important!
- The queen attacks the pawn on e7. In the light of black’s next move, this also doesn’t matter.
Black’s moment has finally arrived:
Black plays 3… Bd4 and pins the white queen to the king.
Of course, observing the consequences does not replace calculating variations, but it does help your tactical awareness. In other words, keeping track of the interaction between pieces, pawns and squares can provide useful information to aid your calculations.
The mere thought of having to apply this to your game may initially feel overwhelming and unnecessary. However, by simply practicing it a few times and adopting the habit in your thinking process, you will be surprised how quickly you get used to it and how much it helps you improve your calculation ability.