I was googling a random song lyric and came across this blog post, which led me to this.
He that knows not, and knows not that he knows not is a fool. Shun him He that knows not, and knows that he knows not is a pupil. Teach him. He that knows, and knows not that he knows is asleep Wake him. He that knows, and knows that he knows is a teacher. Follow him. (Arabic proverb)