Claudius Galen, also known as Galen of Pergamon, was one of the most influential figures in the history of Western medicine. Living in the 2nd century AD, Galen was a Greek physician, anatomist, philosopher, and scholar. His works dominated European and Islamic medical thought for over 1,400 years—until the rise of modern medicine during the Renaissance.
Biography
-
Full name: Aelius/Claudius Galenus
-
Lifespan: c. 129 – c. 216 AD
-
Place of birth: Pergamon (modern-day Bergama, Turkey)
-
Profession: Physician, anatomist, philosopher
-
Royal service: Court physician to Roman Emperor Marcus Aurelius
Galen was born into a wealthy family and received a comprehensive education. He began studying medicine at the age of 16, pursuing further training at renowned medical centers in Smyrna, Corinth, and notably Alexandria—then the most prominent hub of medical knowledge.
Contributions to Medicine
1. Anatomy and Physiology
Due to restrictions on human dissection, Galen conducted anatomical studies primarily on animals—especially monkeys and pigs. Nevertheless, he provided remarkably accurate descriptions of numerous anatomical structures, including nerves, kidneys, the brain, and the circulatory system.
Galen was the first to demonstrate that:
-
The brain—not the heart—is the seat of thought and emotion.
-
Blood—not air—flows through the blood vessels, countering common beliefs of his time.
Despite these groundbreaking insights, he also held some misconceptions, such as the belief that blood was produced in the liver and circulated in two separate systems without a closed-loop structure.
2. Theory of Humors
Galen expanded on Hippocrates’ theory of the four bodily humors: blood, phlegm, yellow bile, and black bile. He believed that health depended on the balance of these humors. Though now obsolete, this theory served as the foundation for diagnosis and treatment in both Western and Islamic medicine for many centuries.
3. Pharmacology and Therapeutics
Galen was also renowned for his pharmaceutical expertise, formulating hundreds of remedies for common ailments. The term “Galenic medicine” refers to traditional remedies derived from herbs and natural substances, prepared according to Galen’s methods.
Legacy
Galen authored nearly 500 medical texts, though only a portion have survived intact. Translations into Arabic and Latin later became core materials in medical education across Europe and the Islamic world from the 9th to the 16th century.
His influence began to decline during the Renaissance, as scientists like Andreas Vesalius and William Harvey critically reassessed and corrected many of his anatomical and physiological assumptions.
Conclusion
Despite the limitations of his era, Claudius Galen remains one of the foundational figures in ancient medicine. His logical reasoning, observational skills, and scientific methodology paved the way for future developments in medical science.
“Medicine is not merely a craft, but a philosophy of life.” – Claudius Galen