In the 19th century a direct result of the scientific work in exploring the relationship between vision and perception was the creation of a number of philosophical/optical toys designed to trick the mind. These toys undermined the relationship between real and make-believe which was particularly interesting for the writers like J.M. Barrie, who all his life was fascinated with the boundaries between fact and fiction. His play «Peter Pan, or the Boy who Wouldn’t Grow Up» and the imaginary island of Never Land may be regarded as philosophical toys themselves.