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

ROBERTO CASATI

While watching a lunar eclipse years ago, Casati had an epiphany: Shadows don't hide; they reveal. For the next few years, he set about discovering how ancient and modern philosophers, astronomers, and artists manipulated and understood shadows. Casati points out that vision can't DO without shadow and explains how biological systems adapt to levels of darkness, usually to defend against predators. TWO thousand years ago, Plato reflected on how an object's shadow can be a tool of knowledge. Modem astronomers agree, as they use shadows for deducing sizes of and distances between planets. Casati breaks down , the mystery of shadows in an effort to reconcile their mystique with the scope of the knowledge that scientists can glean from them. Knopf, 2003, 230 p., b&w photos/illus., hardcover, $24.00.