Warning: this section gets gorey. We'll start off with fatality, trauma, and bear attack. Neurologists Robert Sapolsky and Antonio Damasio weigh in on 19th century philosopher William James, and his theory of emotion (and of bears), which says “emotion is a slave to physiology.”

Then we'll look at sensations of feeling that hang on long after the physiology goes away. Radiolab takes a field trip to the National Museum of Health and Medicine, Armed Forces Institute of Pathology (a collection of medical oddities), and finds a photograph of the severed feet of Civil War soldiers (pictured, on the right.). Photo courtesy of the National Museum of Health and Medicine, Armed Forces Institute of Pathology, Washington, D.C., CP 1043.

And then we'll speed back into the present-day to see brain doctor V.S. Ramachandran solve the case of a painful phantom limb. Pain relief by but mere smoke and mirrors.