The theory of visual perception that Irvin Rock develops and supports in this book with numerous original experiments, views perception as the outcome of a process of unconscious inference, problem solving, and the building of structural descriptions of the external world. It is a radical departure from his earlier work and contrasts with traditional perceptual theories like those of James J. Gibson or the Gestalt view.Rock experiments with a series of phenomena, like motion perception, illusory contours, and size and brightness constancy, and shows that they can be understood in terms of the knowledge applied by the visual system to the interpretation of the retinal image. His work largely complements that being done in artificial intelligence, demonstrating that the visual system is far more subtle and intelligent in many tasks which have not yet been modelled on the computer.Irvin Rock, a noted investigator of perceptual phenomena for nearly three decades, is Professor of Psychology at Rutgers University.