Aretaeus of Cappadocia, a district of Asia Minor, lived during the second century A. D. He was a man of very broad culture. From the fact that he assigned an important rôle to the pneuma, he is usually classed among the Pneumatists. He does not appear, however, to have taken a very active interest in the doctrines of that school, and both Le Clerc and Daremberg seem disposed to call him an Eclectic, and we may therefore rank him as one of the independent physicians of that period. It is doubtful whether he ever practiced in Rome. His two treatises--one on the causes and means of identifying acute and chronic diseases, and the other on the treatment of these diseases--are written in Greek, and are characterized by the clearness and simplicity of his descriptions, which very closely resemble those of Hippocrates, and by the soundness of the advice which he gives in regard to the methods of treatment.[36] In his conceptions of what a physician should aim to be, Aretaeus maintained a very high standard. Some of his views regarding human physiology and pathology are given here very briefly: Respiration serves the purpose of cooling the warmth of the heart, and the lungs are therefore prompted by the latter organ to draw cool air into their cavities; digestion takes place not only in the stomach but also in the intestinal canal, and owes its origin to warmth; the cerebral nerves, close to the spot from which they originate, cross from one side to the other, and by the aid of this fact paralysis on one side of the body may be explained. Aretaeus has gained considerable fame, says Puschmann, from his description of the “Syriac ulcer,” the picture of which he draws agreeing perfectly with what is known to-day as pharyngeal diphtheria. In various places throughout his writings he displays a thorough knowledge of normal anatomy--as, for example, when he describes the ramifications of the vena portae and gall-ducts of the liver. He was also well informed in matters belonging to the domain of pathology, for he gives admirable descriptions of many of the diseases--for example, pleurisy with empyema, pneumonia, pulmonary consumption, cerebral apoplexy, paraplegia, tetanus, epilepsy, diabetes mellitus, gout, etc. From the character of these descriptions one is strongly tempted to believe that he must have made a certain number of postmortem examinations.