[The nature of internal medicine].

We investigate here the problem of the nature of Internal Medicine in the context of the different medical disciplines. After reviewing the origins of Internal Medicine and the changes it has undergone since the early 19th century, we deal with the present crisis of this medical branch and the reasons for it. In Italy, the crisis of Internal Medicine began at the dawn of this century when Neurology became a distinct discipline, isolated from the rest of Clinical Medicine. The present-day crisis is determined by the fact that the different constituent parts of Special Medical Pathology have become autonomous specialist disciplines: this situation has convinced some specialists that Internal Medicine, as a single branch, no longer exists. We thus examine the "justification" for the existence of Internal Medicine. Specialist disciplines were originally created to permit deeper analysis of pathological phenomena; however, the great emphasis on detailed and precise analysis of the different phenomena has paved the way for immense progress in pathophysiology and diagnosis, while the synthetic approach fundamental to Clinical Medicine has been neglected. After referring to Claude Bernard's idea that an organism is greater than the sum of its parts, we note that nowadays considerable importance is given to the "whole", that is, to the global study of very complex systems. We thus examine the thesis of Internal Medicine (which views the organism as a whole) as the specific clinical tool enabling the physician to evaluate each single pathophysiological phenomenon.(ABSTRACT TRUNCATED AT 250 WORDS)