For Plato, shadows were the symbol of our limitations. For Galileo, they knocked the Earth from the center of the cosmos. They are a source of fear and a symbol of ignorance, and they loom large in art and design, mythology and folklore, physics and metaphysics, and architecture and urban planning. From shadows puppets and the psychology of shadows to the role of shadows in astronomy and the influence of shadows on the architectural profiles of our cities, Roberto Casati awakens our fascination in this tour-de-force of investigation and imagination.