The eclat that Hippocrates had given to the teaching of the Asclepiadae of Cos, survived him : many members of his family followed in his footsteps, and sustained the honor of his school. Among others, may be mentioned Thessalins and Draco, his sons, and Polybius, his son-in-law, to whom arc attributed some of the writings that form a part of the Hippocratic collection.
Not long after them, Diocles of Carystus flourished in the same schools, who was surnamed by the Athenians, the second Hippocrates, and Praxagoras, of Cos, the last of the Asclepiadae, of whom mention is made in the history of medicine. Both composed several works that are entirely lost. Praxagoras, who is supposed to have belonged to the family of Hippocrates, was distinguished principally for his anatomical knowledge. He supposed, like Aristotle, that the veins originated at the heart. He did not confound these vessels with the arteries, as many of his predecessors, and Hippocrates himself, had done. He supposed they only contained air, or the vital spirit. It is thought that he dissected the human body.
Praxagoras was the first to remark the close connection between the changes in the pulse, and the dynamic state of the economy. He was also the first who attempted to give an explanation of that singular phenomenon, and thus laid the foundation of sphygmology, for before him, medical men had not given this much attention. The Hippocratic works rarely allude to the arterial pulsations, among the symptoms of diseases, and when spoken of, only a secondary importance is attached to them. But, ultimately, the observations of Praxagoras became a fruitful source of indications ; this order of signs was even greatly exaggerated, as always happens in great discoveries, and efforts were made to build on this unique foundation, an entirely new system of semiology.
The reigning theory in the school at Cos, as we have before said, was that which made the health depend on the exact proportion of the elements of the body, and on the perfect combination of the cardinal humors - the blood, bile, phlegm, and atrabile. This theory was generally attributed to Hippocrates. According to it, all diseases proceed from one of the four elements, heat, cold, dryness, or moist, the excess of which engendered some humor badly concocted, or too abundant, which, by extravasation from its natural reservoirs, passes into parts not habituated to its presence. The equilibrium is established by the coction and evacuation of the piccant humor. This doctrine, which was taught almost exclusively, until the foundation of the school at Alexandria, constituted the ancient Dogmatism, so named, doubtless, because it embraces the most anciently professed dogmas in medicine.
Amongst the most famous sectators of the Hippocratic Dogmatism, we shall name two philosophers, Plato and Aristotle, whose opinions have exercised a great influence on the march of the human mind in general, and particularly in respect to medicine.
From History of Medicine by P.V. Renouard M.D.