An oath taken by physicians usually on receiving the doctoral degree, whereby they promise to observe ethical principles in the practice of medicine. The oath is named for Hippocrates of Cos (470–380 bce), who belonged to the medical guild or brotherhood of sclepiads and is honored as the Father of Medicine because he first separated the art and science of medicine from philosophy and religion. But although the oath survives among the numerous and various writings composing the hippocratic corpus, modern scholars doubt that it was the work of Hippocrates himself. Its prohibition of suicide, euthanasia, abortion, and surgery (all of which were accepted or condoned among the Asclepiads) suggests rather a Pythagorean origin. The date of its composition and the original manner of its use are unknown.