When the enemy’s intention is obvious and the ally’s attitude hesitant, induce the ally to fight the enemy while preserving one’s own strength. This can be inferred from Sun.

To avoid getting incriminated for his act of murder, a person can sometimes conduct the act with a “borrowed knife”, which generally refers to someone else who holds a grudge against the victim. By inducting a third party to commit the murder, one will be able to achieve one’s goal without being held responsible for it. In military contexts, the idiom advises the commander to exploit the conflicts among various powers. To fight a strong enemy, he should find out the power groups that are at odds with this enemy and thereby induce them to fight it in his instead. In this way, he will get twice the result with half the effort.

According to ancient Chinese military strategists, when the two sides are evenly matched and another power suddenly enters upon the scene, the final outcome will undoubtedly depend on the posture of this third side; it should be won over by every possible means. Conversely, if a state tolerates its neighbor’s continuous aggrandizement without checking or making use of it, the state is destined to deteriorate.