This visually gripping book focuses on a central but relatively unexamined aspect of the work of Salvador Dali: his fascination with optical effects and visual perception. The book examines Dali's use of various pictorial techniques, photography, and holograms to further his exploration of visual perception and the ways that optical illusion affects our sense of reality. Dawn Ades and other authorities in the field discuss such paintings as The Enigma of William Tell, in which Dali experimented with anamorphosis, the perspectival distortion that produces on the canvas elongated forms demanding an oblique viewpoint. They also note his interest in other more conventional forms of perspective and their sources in both Dutch and Italian art. They study his development of the famous double image, the "paranoiac-critical method" that produced images that could be "read" in multiple ways, as seen in his Apparition of a Face and Fruit Dish on a Beach or Impressions of Africa. And they reveal his fascination with optical effects and three-dimensional illusions that is apparent in his post-war work: the "screen-dot" paintings like Sistine Madonna or Portrait of my Dead Brother, in which an image emerges from a "pointillist" surface; the striking stereometric paintings he began in the early 1970s - twin panels that have to be viewed through special lenses and his holograms. The authors explore these works and many others, pointing to their sources in scientific theories of perception and perspective and comparing them with the work of such twentieth-century artists as Marcel Duchamp, who was similarly concerned with optics. The book is the catalogue for an exhibition at the Wadsworth Athenaeum, Hartford, Connecticut, from 21 January to 26 March 2000; at the Hirshhorn Museum and Sculpture Garden, Washington, D.C., from 19 April to 18 June; and at the Scottish National Gallery of Modern Art, Edinburgh from 23 July to 1 October.