Not just among religion do we find orthodoxies afraid of truth...
Following the Hippocratic method of learning through experience, a great mind arose in the second century CE by the name of Galen. While the school of Hippocrates focused on examining and keeping track the progress of disease and became highly skilled in diagnosis, Galen took medicine into the mostly previously unknown area of internal anatomy. Through his experience in dissection and vivisection of many animals (dissecting the human body being considered desecration in those times) he became a forefront expert of animal anatomy of his time and proved a great many things. Among them being that the arteries held blood, the kidneys produce urine, the diaphragm and thoracic muscles controlled inspiration, and that the brain controlled the body.
Galen’s work had been the medical orthodoxy for 1400 years. His work was so expansive (Galen was very prolific with about 400 books to his name, quite a lot to have from any time, not to mention from antiquity) and he wrote in such an assertive absolute style that it would take a person of great personal self-confidence to challenge him, especially as his authoritative stature only grew as the centuries passed. And although Galen himself touted reliance on people’s own senses and not on authorities, his work was considered the peak of medical knowledge and it was thought that further investigation was pointless since everything was already known. For centuries, medical professors would intonate Galen’s work from atop an elevated platform, while a semi-educated barber-surgeon would dissect a dead body down below for the sole purpose of showing students Galen’s correctness.
However, Galen was also very limited through his lack of access to actual human remains and many of his observations, though he claimed them accurate for human anatomy, were simply wrong. It was not until the 16th century that Andreas Vesalius, a Belgian, showed Galen’s many errors. Through his own iconoclastic investigative dissections of actual human remains, he found that Galen’s assertion of there being holes in the septum of the heart which made it possible for the blood to pass around the body (this was far before circulation of the blood was discovered in the 17th century by William Harvey) was completely wrong; there were no such holes. The rete mirable, a network of blood vessels in the neck, which Galen said was there to purify the blood was actually not even part of human anatomy, but is found in other animals, like sheep. All in all, over two hundred errors on Galen’s part were found by Vesalius and recorded in his revolutionary text: "De Humani Corporis Fabrica Libri Septem."
But Vesalius’ discoveries were not accepted so gracefully by all. His former friend and teacher, Jacobus Sylvius was so scornful of Vesalius’ assertions that he held nothing back in his malicious rhetoric against Vesalius. He wrote in his work that it was produced to expose "the error-ridden filth" of "that insolent and ignorant slanderer who has treasonably attacked his teachers with violent mendacity." Most of the medical authorities at the time were unwilling to accept Vesalius’ discoveries and remained loyal and faithful Galenists their whole lives. Medical dogma for nearly 1500 years is hard to lose so quickly.
The reason for the title of this post though is that Sylvius in one of his more imaginative apologetic responses was that Galen wasn’t wrong, but that human anatomy had changed since his time. Sound familiar?