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Galen

galen

Lived 129 A.D. – c. 216 A.D.

Galen’s medical doctrine dominated the Western and Arab worlds for close to 1500 years.

Galen was a Greek who became the Roman Empire’s greatest physician, authoring more books still in existence than any other Ancient Greek: about 20,000 pages of his work survive. He was the personal physician to Rome’s Emperors for decades.

He consolidated the work of previous Greek medical researchers, adding the results of his own research to create an incredibly long-lasting medical doctrine.

Galen had great expertise in anatomy, surgery, pharmacology, and therapeutic methods. He is famous for bringing philosophy into medicine – although most of his philosophical works have been lost.

We know more about him than other ancient scientist because of the sheer abundance of his medical writing.

Today, some practices promoted by Galen are still recognized as useful, while others are regarded as dangerous.

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Galen’s Early Years and Education

Galen was born in the year 129 A.D. in the wealthy Greek city of Pergamon in the Eastern Roman Empire. Today Pergamon is in Turkey. Sometimes people use the names Galen of Pergamon or Claudius Galen to identify him.

Pergamon was an ideal place for Galen to grow up; it was one of the most important cultural cities of ancient times, with a highly active intellectual community. Its library was bettered only by the Great Library of Alexandria.

Galen’s father, Nicon, was a very prosperous architect and mathematician. He was highly ambitious for his son, desiring that he should become one of Pergamon’s greatest minds. He saw to it that his son was educated to a high standard in the classic Greek fields of geometry, philosophy, logic, and literature. He also taught his son not to mindlessly follow any one school of thought, but to think for himself and judge every issue on its individual merits.

Like other wealthy people in those times, Galen’s family were slave owners, using slaves to do all the routine work.

A Greek God Intervenes

asclepius

The Greek god of healing, Asclepius. Although Galen believed Asclepius came to his aid, he also came to believe there was only one God. This made the later Christian and Muslim worlds much more receptive to his work.

When Galen reached 16 years old, something remarkable happened.

His father had a dream in which the Greek god of medicine, Asclepius, told him Galen must divert his efforts to medicine and healing.

Nicon was not one to disobey the gods; Galen immediately dropped out of his logic and philosophy classes in favor of medicine.

For the rest of his life, Galen believed that Asclepius came to help him whenever he was badly in need of help.

Although he spent most of his time on medical work, Galen continued to think about philosophy. He believed the best physicians mixed philosophy with medicine.

12 Years Becoming a Physician
Galen became a trainee doctor at a local upmarket hospital/health resort, learning about medical methods for almost four years, mainly from Satyrus, a well-known physician.

His father Nicon died and left Galen a large amount of money. Galen, who was almost 20 years old, decided it was time to spread his wings. He traveled around the Mediterranean learning the latest techniques in medicine and healing.

He ended his travels in the great city of Alexandria’s medical school, where he studied for about five years. Galen disliked almost every aspect of life in Alexandria, except for what he could learn there.

He returned to Pergamon aged 28 or 29. He had been in danger of becoming an eternal student – if you are rich and enjoy learning as much as Galen did, you can always find more to learn.

Galen Becomes a Professional Physician

Galen returned to Pergamon as an elite physician. He had spent 12 years learning all of the different doctrines of ancient medicine from around the Mediterranean. He had seen ineffective techniques and effective techniques, and now applied his own skills to developing a range of effective methods.

He chose to work in an area where you could not hide from your mistakes. He became physician to the gladiators of the Temple of Pergamon’s High Priest. According to Galen, his four years in this practice enabled him to learn even more about medicine.

The relationship between diet and health is not only a recent issue: Galen identified the importance of a healthy diet for the well-being of the gladiators in his care.

He thought of the gladiators’ wounds he treated as ‘windows,’ allowing him to see the functions of various parts of the body. He learned the best ways of treating wounds and trauma, and also learned how important good hygiene practices are. He reduced the death rate among gladiators dramatically, winning the admiration of the High Priest.

The ‘windows’ proved to be very important to Galen’s increasingly sophisticated understanding of human anatomy, because dissection of human bodies was made illegal in the Roman Empire in the year 150 A.D.

The Road to Rome and Ranting

Roman Surgical Instruments

Roman Surgical Instruments

There is a saying that ‘all roads lead to Rome,’ and it was inevitable that a highly skilled, ambitious man like Galen would travel to Rome itself.

In the year 162, age 33, Galen arrived in the Eternal City.

He did not stay permanently at this stage though: his medical teachings contradicted the methods of Rome’s established physicians, who deeply resented him – Galen described them as unscrupulous thieves, more interested in money than healing and truth.

Fearing for his life, in about 166 Galen fled Rome for Pergamon until the storm died down.

Throughout his life Galen enjoyed nothing more than a good rant at anyone who practiced medicine in ways he disagreed with – the rants became a feature of his written work.

Personal Physician to Rome’s Emperors

Although he fled from Rome, he left a positive impression with the city’s most powerful men. In 169 A.D. the Roman Emperor Marcus Aurelius summoned the 40 year-old Galen back from Pergamon to become his personal physician, taking him north to where Rome was warring with Germanic tribes.

Emperor Marcus Aurelius described Galen as:

“First among doctors and unique among philosophers.”

A year later, Galen returned to Rome, becoming physician to Marcus Aurelius’s son, Commodus, who became Emperor in 180 A.D.

Galen acted as Commodus’s physician all the way through his increasingly megalomaniacal reign, which ended with his murder in 192 A.D.

During Commodus’s reign, Galen did a great deal of writing, presumably trying to stay out of Commodus’s reach as much as possible when he wasn’t actually treating him!

Galen obviously impressed Rome’s political elite, because when Septimius Severus became Emperor in 193 A.D. after a period of political turmoil, the 64 year-old Galen continued as personal physician to the new Emperor.

Galen – Master of Medicine

Galen was a compiler, consolidator, and critic as well as a discoverer.

We have to be careful not to credit him with other people’s discoveries. Galen was a prolific author, and much of what he described he owed to earlier Greek physicians, such as Hippocrates, Herophilos, Celsus, Alcmaeon, Praxagoras, Herophilos, Erasistratus and Asclepiades.

Galen mentioned earlier physicians by name in his books, helping preserve their names in history, because it is through Galen that we learn about the discoveries some of these earlier scientists and physicians made.

He took the earlier work and compared it with his own experimental and practical findings. If he could confirm their work, he would use it; otherwise, he would criticize it, and say why it was wrong.

He had an absolute belief in the power of experiment and observation. He did not believe in merely following what books had told him. He needed to verify the truth for himself.

Galen’s 1500 Year Domination of Medicine

Using his own and other people’s discoveries, Galen molded a medical doctrine that dominated medicine in Europe and Arab countries for 1500 years.

Although practitioners in Arab countries and Persia noticed problems with aspects of Galen’s work, it seems nobody had the authority to completely overturn what had been the final word in medicine for so many centuries.

In Europe the fall of Rome was followed by the dark ages. Medicine entered its own dark age, and far from making progress, medical practices actually went backward until the Renaissance revived interest in progress again.

Andreas Vesalius and William Harvey in the 1500s and 1600s finally exposed flaws in Galen’s understanding of human anatomy and blood circulation. With his doctrine undermined, other unreliable aspects of his work were then gradually identified.

Nevertheless, bloodletting – one of Galen’s recommended methods – was still being used in 19th century Europe. In 1852 Ada Lovelace, who was dying of uterine cancer, was treated with bloodletting. The treatment probably killed her faster than the cancer alone would have.

Nowadays – when we take progress for granted – it is amazing to think that medicine made so little progress for about 1500 years. It’s as if we in modern times were using, with few modifications, the technology of 500 A.D.!

Flawed Anatomical Research

Although Galen learned a lot about anatomy by treating wounded gladiators, Rome’s ban on human dissection meant his anatomical research had to be carried out on animals; he dissected Barbary apes and pigs, both living and dead.

Galen believed the best way to learn about anatomy was dissection. Some of his mistakes arose because he could not dissect human bodies and had to make the assumption that what he found in pigs and primates applied to humans. With hindsight, we know he was wrong to make this assumption.

Galenism

So influential was Galen that his methods came to be known by the word Galenism. To come close to describing Galenism completely or even partially would require a long book. Rather than that, here are a few bullet-points about Galenic medicine. Please remember, some aspects of Galenism were not actually discovered by Galen himself – he credited other scientists too.

A Sampling of Galenism’s Successes

  • Diagnosis of disease by careful attention to the patient’s pulse.
  • Diagnosis of disease by careful attention to the patient’s urine.
  • Removal of cataracts from patients’ eyes.
  • Diagnosis of physical symptoms caused by psychological disturbance.
  • Proof that urine forms in kidneys, not the bladder.
  • Discovery that arteries carry liquid blood rather than, as previously thought, gaseous air.
  • Identification of 7 of the 12 cranial nerves – such as the optic nerve and acoustic nerve.
  • Identification of two types of blood – bright red and dark red.
  • Discovery that the heart has four valves and they allow blood to flow in only one direction.

A Sampling of Galenism’s Failures

  • Belief that diseases are caused by bad air from rotting animal and plant matter.
  • Belief that dark blood in the veins is manufactured in the liver to be consumed by the body as food.
  • Belief that brightly colored arterial blood is made by the heart to deliver ‘vital spirits’ to the body.
  • Routine use of bloodletting as a therapy.
  • Belief that arteries are linked to veins by fine blood vessels through which blood and air pass.
  • Belief that microscopic pores in the heart’s septum connect the left and right sides of that organ.
  • Use of Hippocrates system of ‘humors.’ Hippocrates thought imbalances in the humors of black bile, blood, phlegm, and yellow bile caused disease. Galen added his own contribution of four temperaments, one for each humor:
        • Black bile matched melancholic, which meant depressed and despondent.
        • Blood matched sanguine, which meant passionate and optimistic.
        • Phlegm matched a phlegmatic, which meant unemotional and apathetic.
        • Yellow bile matched choleric, which meant quick tempered and stubborn.

The End

Details of Galen’s death are vague. Modern scholars believe he died in about the year 216 A.D., aged 86 or 87, probably in Rome.

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