A middle-aged, fairly unremarkable man in a gray suit is sitting at a coffee bar in the market reading his newspaper and sipping a cup of coffee. At the sound of the commotion he looks up, puts his coffee cup down on the saucer, neatly folds his newspaper and places it on the counter. He gets up from his seat and makes his unhurried way across the market. Reaching the boy (who is still standing, but only just) the man takes hold of the kid and squeezes gently but firmly. After a few seconds the boy coughs up the quarter, which the man catches in his free hand.
The man then walks back to his seat in the coffee bar without saying a word. As soon as he is sure that his son was fine, the father rushes over to the man and starts effusively thanking him. The man looks embarrassed and brushes off the thanks. As he's about to leave, the father asks one last question. "I've never seen anybody do anything like that before - it was fantastic - what are you, a surgeon or something like that?"
"No" the man replies, "I work for the IRS, getting people to cough it up is my business."