In the countryside, a guy’s car gets stuck in a muddy rut. Fortunately, a farmer is just walking his strong-looking shire horse past.
“Don’t worry, there,” says the farmer, hitching the horse to the car. “Soon have you out.”
Then he calls out to the horse “Pull, Dobbin!”
But the horse doesn’t budge, so he tells it “Pull, Barney!”
Still no response, so he says “Pull, Harry!” and this time, the horse gives an almighty tug and the car comes free.
“That’s great, thanks very much,” says the driver, and then asks “Couldn’t you remember his name or something?”
“No, it’s just that Harry’s blind,” says the farmer. “He wouldn’t bother trying if he thought he was the only one pulling.”