Scott Alexander asked some of his readers to submit book reviews that he’ll be publishing anonymously to allow the rest of the readership to vote on. Friday’s submission was a review of the work of Galen of Pergamon … to help determine if he deserves all the kicks he’s received from other writers over the last two millennia:
Aelius Galenus or Claudius Galenus (henceforth “Galen”) was born in Pergamon, a town in modern-day Turkey, in 129 CE. At the time, it was a part of the Roman empire, and a major intellectual center. Galen’s father was an architect; while rich, he was not considered to be particularly high status. Since there was little pressure for his son to go into a traditional career, instead of the “safe” subjects of literature and rhetoric that most Romans studied, Galen got an unusual education in mathematics and geometry.
(His father’s patient encouragement has its foil in his mother, who “flew into rages and bit her servants, a practice of which Galen disapproved.”)
When Galen was a teenager, however, his father had a dream where the god of medicine appeared and told him that his son should study medicine, so Galen started training as a doctor.
During this training Galen became familiar with the writings of Hippocrates, who had lived about 600 years earlier. Hippocrates had introduced the idea of the four humors to medicine — four fluids that congeal together to form our flesh and organs, and which co-mingle in our veins in their liquid form. Hippocrates came up with this system, but Galen would be the one to make it world-famous.
I could try to describe the theory myself, but actually Hippocrates does a great job on his own:
The Human body contains blood, phlegm, yellow bile and black bile. These are the things that make up its constitution and cause its pains and health. Health is primarily that state in which these constituent substances are in the correct proportion to each other, both in strength and quantity, and are well mixed. Pain occurs when one of the substances presents either a deficiency or an excess, or is separated in the body and not mixed with others.
All disease and illness, in this system, were the result of an imbalance in the four humors. From this perspective, treatments like bloodletting make perfect sense. By opening up the veins, the excessive humors drain away, leaving the patient more balanced — in better humors.
Long-term trends towards any of the humors were responsible for what we would call personality. Hence the terms sanguine, phlegmatic, melancholy and so on for different personal traits and emotional conditions.
This is the theory that he would put his weight behind, and which he would eventually be responsible for bringing to the majority of the western world.
When Galen was 19, his father died, leaving him independently wealthy. Hippocrates wrote that a good doctor should travel, so Galen ended up spending a decade studying with medical experts from various schools in cities all around the Mediterranean, including Alexandria.
After this, he came back to Pergamon where he got a job as the doctor treating the gladiators of the city. This was an unusual step for someone of his wealth and education, because despite their popularity as a form of entertainment, gladiators at the time were considered extremely low-class.
It’s not clear why he took this job, but it seems likely that it influenced how he thought about medicine. Spending long hours stitching gladiators back together gave him a detailed knowledge of human anatomy, which other doctors of the time lacked. It sounds like he did a great job, too, because only five of the gladiators died during his time there — compared to 60 under the guy who had the job before.
Eventually all roads lead to Rome, of course, and Galen arrived in 162 CE. His lectures and demonstrations made such an impression, and ruffled so many feathers, that he was afraid of getting poisoned by the Roman doctors and eventually left to save his life. In 169 CE, however, a great plague (probably smallpox) broke out, and Marcus Aurelius summoned him back to Rome to serve as court physician. Marcus Aurelius died the next year (according to some sources, of the plague), but Galen ended up with a longterm post in Rome as physician to the new Emperor, Commodus.
Galen himself died some time between 199 and 216 CE, at the the ripe old age of between 70 and 87.