不耻下问

Bow down one's ear.

Though old and wise, yet still advise.

It is lawful to learn even from an enemy.

eg：The teacher bowed down the ear to one of his students, asking him what one should do in such situation.

中英俚语俗语来源：论语：“敏而好学，不耻下问。”

反义词：刚愎自用 Reckon without one's host.