知己知彼 [ㄓ ㄐㄧˇ ㄓ ㄅㄧˇ; zhi1 ji3 zhi1 bi3] Know yourself, know your enemy (idiom, from Sunzi's Art of War 孫子兵法[ㄙㄨㄣ ㄗˇ ㄅㄧㄥ ㄈㄚˇ; sun1 zi3 bing1 fa3]) ◄ ►