It happened on a crowded bus during the rush hour. A boy of about twelve was sitting by the window, watching the changing scenery and pretending not to see the old men and women standing near him. A distinguished-looking gentleman asked the boy: If I give you 5 pounds will you stand up and let me take your seat? — Sure! — answered the boy, smiling. The man took money out of his pocket and handed it to the boy. The boy took the money and stood up at once. — The seat is yours! — said the man to an elderly lady standing next to him. She blushed and answered: — Thank you very much, but I can't possibly take the seat for which you have paid money! — Forget about that, Madam. You see, I'm an old teacher. I have given the boy some money to teach him a lesson. It is not too expensive! The lady sat down and asked the boy: — I say, Bob, have you thanked the gentleman for the money he gave you?