Pliny the Elder, in the first century AD, conducted experiments to discover whether a dead body was heavier than a living. Like many others who repeated the experiment, he presumed it would be, since the soul, its light part, had fled. In 1907, Dr Duncan McDougall of Massachusetts set out to weigh patients on the point of giving up the ghost, to prove that the body in fact lost weight (21 grams in the folk imagination) at death. What happened between Pliny and McDougall, to bring about this shift from the assumption that the soul was a principle of levity to the idea that it must be ponderable? One answer is the physics of air. Until Lavoisier explained combustion, physicists continued to believe in a substance called phlogiston, which, like Pliny's soul, had among its qualities that of lightness. Extract the phlogiston from a substance by burning it, and it was thought to gain weight because of a loss of this lightness.
In our time, the soul has been progressively more ma-terialised. That the soul should now be thought to be no longer purely immaterial, but constituted from different forms of exotic matter, is a proof of the necessity of physics for any metaphysics. In her tirelessly inquisitive, myriad-minded Phantasmagoria, Marina Warner conducts her own exercise in weighing the modern soul. The book moves through a range of soul-stuffs and material contrivances that, since the Renaissance, have bodied forth ideas of soul, spirit, mind and life: wax, air, clouds, shadows and reflections.
Her first section deals with wax, showing how from the 18th century it became the favoured medium for capturing the newly important idea of the quiddity of the individual person. The second and third sections consider how soul has been bodied forth in more volatile or airy matter - from the froth of the sperm that Aristotle believed contained the pneumatic life-principle, through angelic aviators of the outer air, and the sportive morphology of clouds.
Increasingly, the concern with external spirits - demons, sprites, the departed - yields to a concern with the nature of the mind and its functions - dream, memory, imagination. Warner shows how indispensable the forms of visual technology that have arisen since the 17th century have been to the mind's projection of itself. Similar claims have been made in the past. Daniel Den-nett, for example, has complained about the way our ideas of consciousness are dominated by that ideal inner obser vatory he calls the "Cartesian Theater".
Warner shows how complex and versatile the interaction has been between mind and other forms of visual technology, running through the elaborate phantasmagoria of magic-lantern shows in the early 19th century, the many uses of photography and the development of cinema. Her discussion of the idea of soul-stealing in the context of imperial and ethnographic photography is particularly subtle and arresting.
I am persuaded by her suggestion that the belief, commonly reported of "savage" …