"Borrowing a knife to kill someone" literally means using someone else's knife to commit murder. It is a metaphor for staying out of the fray oneself while using or provoking others to frame or attack a target in order to achieve one's own goals. This stratagem comes from the third of the Thirty-Six Stratagems and belongs to the category of "stratagems for winning battles." Its core lies in "using force to counter force": by creating conflicts and shifting blame onto others, it turns a third party into one's own "knife," while one remains aloof and reaps the benefits. Its deeper meaning refers not only to harming others but also to a sinister kind of scheming: exploiting information gaps, conflicts of interest, or emotional manipulation to make opponents destroy each other, or to make a third party strike on one's behalf. It is often used in political struggles, business competition, workplace intrigue, or interpersonal disputes to describe those who appear innocent on the surface but are in fact manipulating things from behind the scenes. Its emotional coloring is strongly pejorative, implying cunning, treachery, and ruthlessness. In terms of cultural background, it reflects the wisdom of the ancient culture of political strategy, which valued both "borrowing momentum" and "self-protection," but in modern times it is mostly used in a critical context to warn people against being used as a pawn.
📝 Example
1. On the surface, he was friendly with both colleagues, but in reality, he was "killing with a borrowed knife"—deliberately spreading rumors to make the two suspicious of each other, ultimately causing both to suffer while he reaped the spoils like a fisherman. (In this sentence, "killing with a borrowed knife" means exploiting conflicts between others and using a third party's power to strike at one's opponent without showing one's own hand.)
2. In business competition, some companies "kill with a borrowed knife" by reporting a competitor's violations, prompting regulators to step in and thereby weakening the other party's market position. (In this sentence, "killing with a borrowed knife" means using external authority or a third party's power to strike at a competitor while avoiding direct conflict oneself.)