The Shadow Club: The Greatest Mystery in the Universe--Shadows--And the Thinkers Who Unlocked Their Secrets

In this excellent study, an Italian researcher on human cognition sheds light on the subject of shadows. Beginning with his own specialty, the author discusses infants' inability to understand shadows, and how children develop that capacity over time. Throughout history, Casati says, shadows have also played an enormous role in adults' understanding of the world around them. They flourish in myth and folklore, and were crucial in the development of geometry, the earliest branch of mathematics, which led to our first measurements of the size of the Earth. When the telescope was invented, shadows helped prove that the moon was a solid object with a rugged surface, that Venus was not self-illuminating, that Saturn had rings and that the speed of light is not infinite. Closer to home, sundials and sun clocks were the earliest reliable method of telling time, while in art, shadows, though often left out entirely, were basic to the discovery and use of perspective. Add to this coverage a smooth translation, abundant illustrations (including Albrecht Durer's nightmarish device for getting perspective right), and witty section headings featuring Plato arguing with his shadow over the nature of reality. This is a most admirable and illuminating book. 78 illustrations.