In the early 19th century, the French physician Philippe Pinel (1745–1826) propagated a humane treatment for the care of mentally ill patients, thereby founding the field of psychiatry. Pinel rejected the popular notion that mental illness was caused by demonic possession/other magical forces and unchained patients, subsequently proving that they could positively respond to a humane treatment. However, the humane treatment for mentally ill patients was introduced by ancient Greek physicians and philosophers. In the writings of Alcmaeon of Croton (5th century BC), Hippocrates (460–377 BC), Aretaeus of Cappadocia (c. 2nd century AD), and Soranus of Ephesus (98–138 AD), a rational approach can be found for mental illness and its treatment focusing on patients.