I heard this story, years ago:-

Teacher (introducing her class to the saying 'O Tempora, O Mores'):-
"Now Billy, I'm sure you must have heard your grandmother using this expression when she speaks of how times and customs have changed since her childhood"

Billy:- "No, Miss, I don't see my grandmother much, she runs a petrol station on the Outer Hebrides"

Teacher:- "O Tempora, O Mores"