There is often a not-too-subtle corollary that others don’t care, or don’t know, or were not educated. Like so many markers of class, it becomes a signifier of “us” as opposed to “them.”

Faith in these half-remembered and poorly formed “rules” has become just that: a strong belief or trust in something that you can’t explain or prove. Saying “For which room are these the keys?” is demonstrably not the only natural way to formulate this question.