以い毒どく制せい毒どく

noun

fighting fire with fire; using poison to counteract poison; fighting evil with evil

A yojijukugo meaning to use the same harmful means to counter a threat. Often used figuratively for strategies that employ an enemy's own methods against them.

• 彼かれの戦せん略りゃくはまさに以い毒どく制せい毒どくだ。

  His strategy is exactly fighting fire with fire.

• この治ち療りょう法ほうは以い毒どく制せい毒どくの考かんがえ方かたに基もとづいている。

  This treatment is based on the idea of using poison to counteract poison.