Cabinet Magazine has an interview with Victor Stoichita, an art history professor who wrote the book A Short History of the Shadow. In it, Stoichita explores the shadow in art, psychology, and culture. It sounds quite heady, with Stoichita delving into Plato, Pliny, Leonardo, and Warhol, photography, writing, painting, and philosophy. The interview is a nice dip into this curious intellectual terrain though! (Seen here: "Illustration from Ars Magna Lucis et Umbrae, Athanasius Kircher's seminal 1646 treatise on light and shadow. In explaining the principle of the camera obscura, the illustration associates the image and the shadow with the devil.") From the interview:
Your book is the first study of its kind. Why do you think the subject was previously so overlooked?Link
I actually started my research with that very question. Just before the publication of my book, an exhibition on shadows was organized at the National Gallery in London, accompanied by a short but interesting text by the late Ernst Gombrich. But previously art historians took a long time in paying attention to shadows because shadows are, so to speak, heavy, dark, and ugly. Perhaps this is because for the Greeks, the shadow was one of the metaphors for the psyche, the soul. A dead person’s soul was compared to a shadow, and Hades was the land of shadows, the land of death.