Attack a Second Weakness
The principle of the “second weakness” is an important part of attacking positional chess. The theory is that attacking against one weakness is not usually enough to win, because the defender can bring their pieces to defend a single weakness. A lot of attacks then involve “creating a second weakness” on the other side of the board.
Two weaknesses on opposite sides of the board are almost impossible to defend. The attacker flips back and forth, and the defensive pieces also try to swap back and forth to defend. But if the attacker has more mobility, more space, or can attack both weaknesses at once with a centralized piece, then one weakness or other will fail. The attacker then crashes in against one of the weaknesses and will win material and invade the enemy position at that location.
That’s the theory. In practice, this is such an advanced strategy that it is not used by beginners or even by intermediate players. The theoretical justification is that one weakness can be defended, but that theory falls over because beginners and intermediate players are not actually that good at accurately defending. Often a single weakness is enough to win a game in the lower levels of chess play.
Related Chess Tactics
Read more about these related chess strategies: