Kennedy argues that space perception is possible through touch as well as through sight, and aspects of perspective are found in pictures by the blind. He shows that blind people recognize when pictures of objects are drawn incorrectly. According to Kennedy, the incorrect features are often deliberate attempts to represent properties of objects that cannot be shown in a picture. These metaphors, as Kennedy describes them, can be interpreted by the blind and the sighted in the same way.
Kennedy's findings are vitally important for studies in perceptual and cognitive psychology, the philosophy of representation, and education. His conclusions have practical significance as well, offering inspiration and guidelines for those who seek to engineer ways to allow blind and visually impaired people to gain access to information only available in graphs, figures, and pictures.