Attempts to understand the relationship between social behavior and health have their origin in history. Dubos (1969) suggested that primitive humans were closer to the animals because they, too, relied upon their instincts to stay healthy. Yet some primitive humans recognized a cause and effect relationship between doing certain things and alleviating symptoms of a disease or improving the condition of a wound. Since there was so much that primitive humans did not understand about the functioning of the body, magic became an integral component of the beliefs about the causes and cures of health disorders. So it is not surprising that early humans thought that illness was caused by evil spirits. Primitive medicines made from vegetables or animals were invariably used in combination with some form of ritual   to drive harmful spirits away from a diseased body. One of the earliest attempts in the Western world to formulate principles of health care based upon rational thought and rejection of supernatural phenomena is found in the work of the Greek physician Hippocrates. Little is known of Hippocrates who lived around 400 B.C., not even whether he actually authored the collection of books that bears his name. Nevertheless, the writings attributed to him have provided a number of principles underlying modern medical practice. One of his most famous contributions, the Hippocratic Oath, is the foundation of contemporary medical ethics  . Among other things, it requires a physician to swear that he or she will help the sick, keep oneself from intentional wrong-doing or harm, and keep secret all matters to keep the doctor-patient relationship. Hippocrates also argued that medical knowledge should be derived from an understanding of the natural sciences and the logic of cause and effect relationships. In this classic thesis, On Airs, Waters, and Places, Hippocrates pointed out that human-being is influenced by the totality of environmental factors: living habits or lifestyle, climate, geography of the land, and the quality of air and food. Interesting enough, concerns about our health and the quality of air, water, and places are still very much written in the twentieth century. Why did primitive humans rely on magic in their beliefs about the causes and cures of diseases?
Because magic was an inseparable part of their life. Because they had little knowledge about the functioning of the body. Because the diseases were caused by the evil spirits. Because magic must be used in going through the rituals to drive out the evil spirits.