EACH ACH period of history of the human race had its characteristic medical status.
In the beginning the causes of illness and the means of their alleviation were based on the supernatural. The healers were mystics or conjurers.
The next period (400 to 500 B. C.) witnessed the development of philosophy and the dawn of scientific observation in the concept of disease. The devotees of the healing art made a study of man and his reaction to his environment. It was appreciated that these were important factors in the development and well-being of man.
Then followed a period during which the plan of separation was developed. A healer or a physician became interested in or treated a single disorder or a disease of a single organ or system. The human organism as a whole was overlooked in concentrating on a relatively small part. This is like the system of specialties
HEGNER CF. PREPARATION FOR A MEDICAL CAREERPresidential Address. Arch Surg. 1947;55(4):387-393. doi:10.1001/archsurg.1947.01230080395001