Final answer:
Hippocrates is considered the father of Western medicine and believed diseases had natural causes, contributing to the early medical texts and creating the Hippocratic Oath.
Step-by-step explanation:
The ancient Greek considered the father of medicine is Hippocrates. He notably rejected the notion that diseases were caused by supernatural forces, arguing instead that they had natural causes related to the body or environment. Hippocrates and his successors are believed to have composed the Hippocratic Corpus, which is among the oldest medical books in existence. Importantly, he is often credited with creating the Hippocratic Oath, which doctors still use today to pledge their commitment to provide ethical medical care.