Hoffman explains that far from being a passive recorder of a preexisting world, the eye actively constructs every aspect of our visual experience. In an informal style replete with illustrations, Hoffman presents the compelling scientific evidence for vision's constructive powers, unveiling a grammar of vision - a set of rules that govern our perception of line, color, form, depth, and motion.

Hoffman also describes the loss of these constructive powers in patients such as an artist who can no longer see or dream in color and a man who sees his father as an impostor. Finally, Hoffman explores the spinoffs of visual intelligence in the arts and technology, from film special effects to virtual reality. This is, in sum, "an outstanding example of creative popular science" (Publishers Weekly).