Summary: Imagine that the evidence of someone’s lunch is lodged right between her front teeth, and the struggle begins: Do you tell the person? You have to pull it off with grace so both parties can remain dignified, but that’s tricky, especially if you barely know her. And by that time, would you seem like a jerk for waiting so long to say anything? For the “do you tell the person” question, there’s a simple rule for that.
