聪明一世，懵懂一时
cōng​ming​yī​shì​měng​dǒng​yī​shí

even the wisest can have a momentary lapse

  1. 聪明 聰明 cōng​ming adjective
    intelligent
    intelligent; bright; clever
  2. 一世 yī​shì
    one's whole life
    one's entire lifetime; lifelong
  3. ， měng
    non-Chinese
  4. 懵懂 měng​dǒng
    confused
    muddled; ignorant; dazed and lacking understanding of things
  5. 一时 一時 yī​shí
    for a short while
    a short while; for the time being