Galenic Writings 190 – A 1000-Year Reign over Medicine

Apart from Hippocrates, who lived six centuries earlier (see the entry "Hippocratic Oath"), Galen probably influenced the course of Western medicine for longer than any other Greek physician. Born in the 2nd century AD, at the height of the Roman Empire, Galen's medical knowledge, anatomical studies, and enormous collection of writings held sway over his successors for more than a thousand years. According to reports, he sometimes employed 20 scribes to keep up with his dictation! In addition, his animal dissections (cutting animals apart for examination) led to new insights into organ systems.

Born on the western coast of present-day Turkey, he traveled widely before settling in Rome. Because human dissection was illegal, his extensive anatomical research was based on pigs, dogs, and monkeys ("Barbary apes"). Through vivisections (operating on a living animal for experimental purposes), he was able to cut various nerves to demonstrate that the brain controls muscle movement in the body. Loss of voice became apparent after the laryngeal nerve was cut. To demonstrate that the kidneys produce urine, he tied off the ureters and observed swelling in the kidney. As a physician to gladiators, he examined horrific wounds to learn more about human anatomy. He eventually became physician to the Roman emperor Marcus Aurelius, among others.

Of course, not all of Galen's medical findings and theories were reliable. After considering Hippocrates' ideas that disease resulted from an imbalance of the four humors (fluids) — blood, black bile, yellow bile, and phlegm — he extrapolated the concepts to suggest that an imbalance in each humor corresponded to a human temperament (for example, an abundance of black bile corresponded to a melancholic personality). He also incorrectly proposed that venous (dirty) blood was produced and pumped by the liver and arterial (clean) blood originated in the heart, and believed that blood passed between the left and right sides of the heart through invisible pores.

For Galen, philosophy was an important component of every physician's education. After the Roman Empire collapsed, his influence continued as his writings and ideas spread to the Arab world and later to medieval Europe and beyond.

Description of the article image: Gladiators' wounds gave Galen important information about the anatomy of muscles and internal organs. Pollice Verso (1872), by the French painter Jean-Léon Gérôme (1824–1904).

Historical figures mentioned in the article: Galen of Pergamon (129–199)

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