A butcher, shooing a dog from his shop, spots $10 and a note in its mouth: "10 lamb chops, please." Intrigued, he takes the money, gives the dog a bag of chops, and closes shop to follow it.
The dog waits for the green light, looks both ways, and trots to a bus stop. It checks the timetable, sits on a bench, and boards the correct bus after checking its number. The astonished butcher follows.
As the bus heads to the suburbs, the dog enjoys the view. Eventually, it presses the stop button with its paw and gets off, with the butcher in tow.
The dog runs to a house, drops the bag on the stoop, then repeatedly takes a running start and slams itself against the door. Getting no answer, it jumps on a wall, walks around the garden, bumps its head against a window, and finally waits at the front door.
A large man opens the door and begins cursing and hitting the dog. The butcher rushes over, shouting, "What are you doing? This dog is a genius!"
The owner retorts, "Genius, my ass. It's the second time this week he's forgotten his key!"