The theories of Hippocrates and Galen are vitally important to the development of medicine, as they shaped medicine for many centuries to come. Hippocrates was the first to reject the idea that magic, spirits or Gods could cause or cure disease, reforming the course of medicine. Galen followed in the footsteps of Hippocrates, working tirelessly on human anatomy, trying to understand how the body works and what happens when something goes wrong. Without Hippocrates' belief that diseases were a product of nature, revolutionizing medicine, and without Galen's extensive work on the anatomy of the human body, medicine may not have progressed to what it is today. Hippocrates of Cos was an ancient Greek physician who is thought to be one of the most revolutionary figures in the history of medicine. He is called the "father of modern medicine" in recognition of his lasting gifts to medicine as the founder of the Hippocratic school of medicine. This school of medicine modernized medicine in ancient Greece, establishing it as a discipline distinctive from others, particularly theurgy (the practice of rituals, sometimes seen as magical in nature, to evoke the presence of one or more gods). Hippocrates is recognized as the first to believe that ailments were caused by natural causes and not by superstition or the Gods. He separated medical theory from religion, believing that disease was a product of environmental factors, diet, and lifestyle habits. Hippocrates was interested in rational medicine. Hippocrates pioneered scientific approaches to medicine and the practice of clinical observation. His medical practice was based on the observation and study of the human body: a method developed in ...... middle of paper ...... in turn contributed to the development of more accurate theories on the causes of diseases and more effective remedies. More importantly, the theory of the four humours also revolutionized medicine, allowing people to move away from supernatural beliefs and allowing medicine to progress to what it is today. Galen's extraordinary, mostly accurate, theories about the anatomy of the body proved to be an effective foundation for later physicians. Galen further advanced Hippocratic theories by providing a foundation for modern psychiatrists by linking each of the four humors to a human temperament. Hippocrates planted the seeds responsible for today's medical advances, while Galen reaped them, providing a more advanced foundation for modern medicine. Without these two exceptional figures in the history of medicine we would not have been able to progress as far as we have today.