Hippocrates (c. 460–c. 377 BC)

Greek physician, often called the founder of medicine. Important Hippocratic ideas include cleanliness (for patients and physicians), moderation in eating and drinking, letting nature take its course, and living where the air is good. He believed that health was the result of the ‘humours’ of the body being in balance; imbalance caused disease. These ideas were later adopted by Galen.

He was born and practised on the island of Kos, where he founded a medical school. He travelled throughout Greece and Asia Minor, and died in Larisa, Thessaly. He is known to have discovered aspirin in willow bark. The Corpus Hippocraticum/Hippocratic Collection, a group of some 70 works, is attributed to him but was probably not written by him, although the works outline his approach to medicine. They include Aphorisms and the Hippocratic Oath, which embodies the essence of medical ethics.

The Corpus Hippocraticum remains impressive for its focus on observation and the description of symptoms. Diseases are seen as being caused by an imbalance of the four basic ingredients, or humours, of the human body (blood, phlegm, yellow bile, and black bile). This remarkably influential idea perhaps gained credence by analogy with the theory of the four elements of matter of Zeno of Elea and Parmenides. Being vague, the theory of humours was also widely applicable, for instance in its link with the seasons (winter illnesses being characterized by cold and wet discharges). Where given, the treatment suggested consists of eating compensatory food such as hot and dry foods in winter. The Hippocratic tradition in medicine remained dormant until the 18th–19th century, when it was replaced by the germ theory of disease, but the image of Hippocrates as the ideal physician remains today.