It tells a story about a minister named Tian Ji who raced horses with the Emperor of their country.
The rules of horse racing were best of three rounds, and every round he raced, he would lose.
Because nobody's horse could ever surpass the Emperor's horses.
In the end, under the advice of a strategist at home, Tian Ji adopted an even more ingenious method.
The competition was still best of three rounds, with both sides sending out three classes of horses: top-grade, medium-class, and low-class horses.
In past competitions, Tian Ji would always lose.
But this time, he changed his strategy, pitting his low-class horse against the Emperor's top-grade horse, his medium-class horse against the Emperor's low-class horse, and his top-grade horse against the Emperor's medium-class horse. With this approach, he truly achieved two wins and one loss, securing victory.