牽一髮而動全身

qiānyīfà'érdòngquánshēn ㄑㄧㄢ ㄧ ㄈㄚˋ ㄦˊ ㄉㄨㄥˋ ㄑㄩㄢˊ ㄕㄣ

    • lit. pulling a single hair makes the whole body move (idiom)
    • fig. a small change in one part can affect the whole system

Character by character

Sources