Galen

Claudius Galenus of Pergamum (131-201 AD), better known as Galen, was an
antique Greek physician. His views dominated European medicine for over a
thousand years.

Life

Galen was born in Pergamum (modern-day Bergama, Greece) to an architectÕs
family. His interests were eclectic Š agriculture, architecture, astronomy,
philosophy Š until he concentrated on medicine.

By the age of 20 he had become a therapeutes ("attendant") of the god
Asclepius in the local temple for four years. After his fatherÕs death in
148 or 149 he left to study abroad. He studied in Smyrna and Corinth and at
Alexandria. He studied medicine for a total of twelve years. When he
returned to Pergamum in 157, he worked as a physician in a gladiator school
for three or four years. During this time he gained experience of trauma and
wound treatment. He later regarded wounds as Ņwindows into the bodyÓ.

From 162 he lived in Rome where he wrote extensively, lectured and publicly
demonstrated his knowledge of anatomy. He gained a reputation as an
experienced physician and his practice had widespread clientele. One of them
was consul Flavius Boethius who introduced him in court where he became a
court physician to emperor Marcus Aurelius. Later he also treated Lucius
Verus, Commodus and Septimius Severus. Reputedly he spoke mostly Greek,
which was a more respected language of medicine than Latin at the time. He
briefly returned to Pergamum in 166-169.

Galen spent the rest of his life in royal court, writing and experimenting.
He performed vivisections of numerous animals to study the function of the
kidneys and the spinal cord. His favorite subject was the barbary ape.
Reportedly he employed 20 scribes to write down his words. In 191, fire in
the Temple of Peace destroyed some of his records. He died in 203.

Work and impact

Galen transmitted Hippocratic medicine all the way to the renaissance. His
On the Elements According to Hippocrates describes the philosopher's system
of four bodily humours, which were identified with the four classical
elements. He created his own theories from those principles. In turn, he
mainly ignored Latin writings of Celsus.

Amongst GalenÕs own major works is a 17-volume On the Usefulness of the
Parts of the Human Body. He also wrote about philosophy and philology. His
collected works total 22 volumes.

GalenÕs own theories emphasized purposeful creation by a single Creator Š a
major reason why later Christian and Muslim scholars could accept his views.
His fundamental principle of life was pneuma (air, breath) that later
writers connected with the soul. Pneuma physicon (animal spirit) in the
brain took care of movement, perception and senses. Pneuma zoticon (vital
spirit) in the heart controlled blood and body temperature. Natural spirit
in the liver handled nutrition and metabolism.

Galen expanded his knowledge by experimenting with live animals. One of his
methods was to publicly dissect a living pig and cut its nerve bundles one
at the time. Eventually he cut a laryngeal nerve (now also known as GalenÕs
Nerve) and the pig stopped squealing. He tied the ureters of living animals
to show that urine comes from the kidneys. He severed spinal cords to
demonstrate paralysis.

From the modern viewpoint, GalenÕs knowledge was partially correct,
partially flawed. He demonstrated that arteries carry blood, not air and
made first studies about nerve functions, brain and heart. He might have
begun the practice to check the patientÕs pulse. He also found that the mind
was in the brain, not in the heart as Aristotle had claimed.

However, since most of his knowledge of anatomy was based on dissection of
pigs, dogs and Barbary apes, it is flawed from the modern point of view. He
did not recognize blood circulation and thought that venous and arterial
systems were separate. This view did not change before William Harvey in the
17th century. He also assumed that rete mirabile, a blood vessel plexus of
ungulates, also existed in the human body. He also resisted the idea of
tourniquets to stop bleeding and vigorously propagated blood letting as a treatment.

GalenÕs authority dominated medicine all the way to the 16th century.
ExperimenterÕs disciples did not bother to experiment and studies of
physiology and anatomy stopped Š Galen had already written about everything.
Blood letting became a standard medical procedure. The first serious change
in his hegemony was Vesalius.

Most of GalenÕs Greek writings were first translated to Syriac by Nestorian
monks in the university of Jundi Shapur, Persia. Then muslim scholars
translated them to Arabic, alongside many other Greek classics. They became
one of the main sources for Persian scholars such as Avicenna and Rhazes.