People - Greek surgeon philosopher Galen

Aelius Galenus or Claudius Galenus, popularly known as Galen is a Greek doctor-surgeon-philosopher of the Roman Empire. He was born around 129 AD to Aelius Nicon, a wealthy and scholarly Greek architect in Pergamon (now Bergama, Turkey). He not only received a comprehensive education that prepared him for his doctor- philosopher role, he traveled extensively exposing himself to varied medical theories and discoveries before settling down as the personal physician to the emperor in Rome.

Since dissection (cutting of dead bodies for studies) and vivisection (cutting live animals to study) on humans was strictly prohibited during his times, Galen dissected and studied animals including apes and pigs. Based on these studies and the popular four humor theory of his times, he wrote extensively and published hundreds of treatises amounting to over ten million words. These treatises are spread across Physiology, Hygiene, Aetiology, Semeiotics, Pharmacy, Blood letting and Therapeutics. Although his anatomical experiments on animal models led him to a more complete understanding of the circulatory system, nervous system, respiratory system, and other structures, his work contained scientific errors. For example, Galen believed the circulatory system to consist of two separate one-way systems of distribution, rather than a single unified system of circulation. He was also a proponent of the four humour theory and the practice of bloodletting (detailed in one of the previous articles of this issue).

Galen's views dominated and influenced Western medical science for more than 1,000 years, until thereafter

challenged, improved upon and corrected. Although highly criticized for comparing animal anatomy to human anatomy, Galen was convinced that his knowledge was abundant enough in both anatomies to base one on the other.

Galen was a skilled surgeon, operating on human patients. He famously disemboweled an ape and challenged other physicians to repair the damage. When they refused, Galen performed the surgery himself- successfully. In 157 AD, aged 28, he was appointed physician to the gladiators of the High Priest of Asia, one of the most influential and wealthy men in Asia. It has been reported that only five deaths among the gladiators occurred while he held the post, compared to sixty in his predecessor's time, a result that is in general ascribed to the attention he paid to their wounds.

Among Galen's major contributions to medicine was his work on the circulatory system. Before Galen's research, it was believed that the arteries carry oxygen rather than blood. He was the first to recognise that there are distinct differences between venous (dark) and arterial (bright) blood.

Galen was also a pioneer in research about the human spine and the Central Nervous System. Through his vivisection practices, Galen was the first to prove that the voice was controlled by the brain. He would cut open a pig, and while it was squealing he would tie off the recurrent laryngeal nerve, or vocal cords, showing that they controlled the making of sound. He similarly proved his theories of kidney and bladder function by tying off the ureters.

As already mentioned, he was also a skilled surgeon. Many of his procedures and techniques were far ahead of his time, such as the procedures he performed on brains and eyes, particularly cataract correction.

Galen is believed to have worked and written till well into his final years, at least having lived till he was aged 87. And today, close to two thousand years later he continues to be remembered, and is a wellstudied and respectable pioneer of his times, and his life and works continue to be a source of inspiration and fascination for many.