Some of the oldest accounts of epilepsy are found in ancient writings from Babylonia and India (Ayurvedic medical system), dating as far back as 2000 BC. The ancient Greeks saw epilepsy as a supernatural phenomenon, the “holy sickness”. Hippocrates, a Greek physician who lived around 450 BC, believed the illness had natural causes. Over the next 2000 years, various theories emerged to explain its cause: epileptics were possessed by spirits or devils (a view popular at the time of Christ); it was caused by a build-up of phlegm in the arteries leading to the head; it was an infectious disease. Hippocrates' view of epilepsy as a brain disorder didn’t become widely accepted until the 19th century.