What can an ancient debate about an elephant tell us about the history of medicine? To find out, step into the life and times of Galen of Pergamum. Though his name is not commonly recognized today, Galen's writings influenced medical theory and practice for centuries. Luis Salas studies Greek and Roman medicine and philosophy, in particular the works of Galen. Here, Salas shares a fascinating and revealing story about Galen, his rivals, and the heart of an elephant.