In his new book, Cat Sense, John Bradshaw researches cat behavior. John is a cat-behavior expert at the University of Bristol. He notes in his book that when a human enters a room, their dog will change behavior and play with the human in a different manner than he/she might play with another dog. Cats, on the other hand, play with their humans in the same manner in which they play with other cats. This, he says, proves that dogs see humans as different while cats see humans as big, clumsy cats.