On solving mate in n moves chess puzzles
I recently gave the following chess puzzle to the enthusiasts in my circle. White to win in 3 moves.
One of my friends came up with the following two solutions:
- Solution 1: Re7+ Kf8, Qf7#
- Solution 2: Re7+ Kxf6, Qe6+ Kg5, Rg7#
I had to emphasize that solution 2 is the correct solution and solution 1 is not a correct solution for this puzzle. Although solution 1 is a valid sequence of moves leading to a mate for the black, it is not the best from the black’s point of view.
The fundamental principle in solving chess puzzles is that to arrive at the correct answer, one must see the best possible moves and counter moves from both sides.
- Say white starts with Re7+.
- Black has the following possible responses: Kf8 and Kxf6.
- Kf8 leads to an immediate mate with Qf7#.
- Kxf6 delays the mate by one more move.
- From the perspective of black, the objective is to delay the mate as much as possible in order to hope that white may make a mistake later.
- Hence, Kf8 is not the correct response. The correct response is Kxf6.
- White must then respond with Qe6+ in order to force the mate in the next move.
- If white tried Qf7+, then the black king will have options to move on to g5 and delay the mate further.
- After Qe6+, black is forced to respond with Kg5. Then Rg7# finishes the game.
The puzzles are usually designed or picked from real-life games in a manner so that there is just one correct answer which contains the best possible moves and counter moves from both sides towards the desired objective (typically a mate). If there are multiple possible best solutions, they should all involve the same number of moves. So a 3-move puzzle will not have a 2-move optimal solution. Any 2-move solution for a 3-move puzzle will incorporate a weak move from one side.
Rookie chess players have a habit of looking at the game from their own perspective only. Most of the time, as rookies we are too focused on our own plays and strategies that we fail to see how the opponent is going to respond to our attacks. Chess puzzles are meant to develop a thinking habit where we are playing the game from both sides. This means that neither side has the latitude to make any weak moves. Otherwise, the puzzle will either end in less than or more than the desired number of moves.
