John works in the London Home for Lost Dogs. When dogs get lost in London, policemen and other people bring them to John. When somebody loses his dog he comes to the Dogs' Home, and usually the dog is there waiting for him. There are a lot of dogs in the Dogs' Home today and now John is talking to a man and his wife. "We've lost our dog," the man says. "Yes, our beautiful little dog. Is he here?" the wife asks. John says, "Wait a minute, please. There are hundreds of dogs here. All of them are lost dogs. Is yours a big dog or a little one? What colour is it?" "Ours is a pretty little white dog," the wife says. But now a little boy is standing behind the man and his wife. "Please, is my dog here? Mine's a little white dog, too," he says. "Oh, dear," thinks John. "Theirs is white and his is white; theirs is small and his is small. Both their dogs are white and both are small." "Tell me something more about your dogs," John says. The man says, "Ours has black ears, a long tail and short hair." "Mine has, too," says the boy. "Please come with me," John says, "All of you. Come and have a look at all the dogs we have." Outside, there is a yard full of lost dogs. There are three small white ones with black ears. As soon as two of the small, white dogs see their masters, they become very excited. One runs towards the boy and the other runs towards the man and his wife. The two dogs look very much the same, so neither the boy nor the man and his wife can tell them apart. But the dogs recognize their own masters easily.