GALEN, CLAUDIUS. - Physician and philosopher, b. at Pergamum in 129 A.D., d. there in 201. He traveled to Smyrna, Corinth, Alexandria, and in 162 he was in Rome. He was court physician to Marcus Aurelius, whose young son Commodus he treated.
A follower of Hippocrates in medicine, his most original contribution to this discipline was the physiological one, through his studies on the functioning of the nervous system and on the brain, heart, and liver, for which he made use of the vivisection of animals, monkeys, goats, and pigs. He adopted the doctrine of the four temperaments: phlegmatic, sanguine, choleric, melancholic, whose good humoral functioning (eucrasia) produces health while bad functioning produces disease which must be remedied with antidotes. G. was a great proponent of medications, among which the most celebrated was the Theriaca, whose use lasted almost until modern times.
G.'s anatomy is always joined to physiology and very often is compared, and the teleological purpose is most evident, inasmuch as it is subject to the end for which each organ is intended. This characteristic, if it adapted well to the Christian spirit in the Middle Ages, was also a source of many errors. He had a clear vision of the nervous system, both central and peripheral; he described in particular the septum lucidum, the corpus callosum, and the quadrigeminal bodies. He also studied the larynx, discovering the superior laryngeal nerves and the recurrent ones. G., however, wanted to apply to man the anatomy learned from the autopsies of animals. He then stands out as a giant in physiology proper, although even here the errors are numerous. G. had of experiment that exact concept that a modern scientific clinician might have today. He had a vision of the movement of the blood, though not of the circulation of the blood. He demonstrated for the first time that both the arteries and the veins contained blood which, with a wavelike movement, was attracted to the organs, where it was used up. He also distinguished venous blood from arterial blood, the latter of which would have such a color because it was exposed to air. For G. the liver was the center of venous nutritive blood, while the heart was the center of arterial nutritive blood; the right and left hearts were in communication with each other by means of the pores of the septum; the pulmonary veins would have a double course, carrying blood laden with soot to the lungs and bringing purified blood back to the heart, blood that in the end was used up in the organs, even though arteries and veins were in communication by means of intercommunicating vessels. G. also performed experiments on the kidneys and on the nervous system.
As a pathologist G. is based on the concept that every disease corresponds to an organic lesion, and the perceptible effects of the disease are the symptoms. There are three types of diseases: of the simple parts, of the instrumental parts, that is, of the organs, and finally traumatic diseases. His therapy is based on Contraria contrarii, and to each medication G. attributed a humoral characteristic.
His writings amount to 400, of which (of the 108 that have come down to us) the most important are the Anatomical Researches, in 15 books, the Functions of the Organs of the Human Body, in 17 books, the Teachings of Hippocrates and Plato, in 6 books, On the Natural Faculties, in 3 books; important are the Medical Art and the Therapeutic Method, called in the Middle Ages respectively the "Microtechnum" and the "Macrotechnum."
He also had philosophical concerns; he was a convinced teleologist; he saw in nature the concatenation of causes that raises it up to a generating intelligence, though not completely detached from matter: indeed the study of the human body makes one understand the excellence of the spirit that dominates the world.
His orientation may be defined as an eclectic Aristotelianism. The influence of Aristotle is evident especially in his logic (the 4th figure of the syllogism is well known, which G. derived from the analysis of the modes of the 1st figure of Theophrastus and Eudemus), in physics and metaphysics; while in psychology (for example, in the question of the division of the soul) he inclines toward Platonism. Philosophy, identified with religion, is for him the highest among goods.
G. knew Christianity and speaks of it in two passages of the work On the Pulse, regarding the tenacity with which certain physicians assert their opinions without justifying them, like those who enroll in the school of Moses and of Christ (De pulsibus, VIII, 579 Kühn); indeed, he adds, it would be easier to make the disciples of Moses and of Christ change their opinion than the physicians and philosophers faithful to their factions (ibid., p. 657).
He praises the Christians in a passage which is not found in the works of G., but is cited as his by the Arab writer Ibn al-Athir, in turn reported by Abū 'l Fidā' (Historia Anteislamica, ed. Fleischer, p. 109). Referring to the usefulness of parables for the understanding of concepts and noting the use that Christians make of them, he affirms that these "act from time to time as true philosophers. We have before our eyes their contempt for death. A kind of modesty inspires their abstention from the use of love. There are among them women and men who have abstained throughout their whole life from sexual union. And there are others who, thanks to the direction and discipline of the soul and a rigorous application, do not yield to the true philosophers."
This passage, whose authenticity there is no reason to deny, demonstrates the fairness of G.'s judgment concerning the new religion, which was made the object of attacks so unjustified and violent. - See plate CXXVI.
