"Yvain was so distressed at departing from his beloved that his heart did not leave. The king could lead the body, but not the heart, which attached itself so strongly to the heart of the lady left behind that he had not the power to draw it away. The body cannot possibly live without the heart, yet this wonder did happen. The body still held on to life without the heart, which, though accustomed to lodging there, had no desire to follow the body farther. The heart found a good home, and the body lived in hope of returning to its heart. In place of the heart, the body had, in a strange manner, created a substitute out of hope." -- Chretien de Troyes, The Knight with the Lion