"Remember also that every time you open your mouth in the presence of a person who has an abundance of knowledge, you display to that person your exact stock of knowledge or your lack of it! Genuine wisdom is usually conspicuous through modesty and silence."
That's a two-way street, dbosson. I wouldn't hasten to silence him, nor chasten him for opening his mouth "in the presence of a person who has an abundance of knowledge," as you put it.