Galen - Mistakes, Successes and who proved him wrong

• Gained lots of experience as a Gladiator Surgeon
• Wrote over 100 medical books
• Agreed with Hippocrates' 'method of observation'
• Became physician to the Emperor in AD 161
• Discovered that blood vessels did in fact carry blood, not air as commonly believed
• He explained the importance of the pulse in diagnosis
• He proved that the brain and spinal chord controlled the body
• He noted that the body was so intricate that it must have a creator, but did not stress the polytheistic Roman religion, so future societies could easily agree with his work
• His ideas lasted unchallenged for 1500 years after his death

The laws and religion of Rome at the time prohibited human dissection, so Galen could only cut open animals like dogs, pigs and monkeys, which led to crucial mistakes like the shape of the liver. He also let his ego get the better of him, so only published findings that supported his personal view.

Galen built on Aristotle's Four Humours theory and supported the Treatment of Opposites, which although is logical, holds little value in terms of cures for disease.

Galen's work lasted for many years, thanks to the work of the Arabists, and later the Christian Church. Although this provided medical diagnosis based on logic and reason, he was so crucially wrong with certain things that the next 1500 years saw a state of medical regression, and anything that went against the work of Galen was ignored.

Vesalius - Published findings in 'The Fabric of the Human Body' 1543

• Proved that humans only had one jaw bone and not two, as dogs have
• Proved that there were no holes in the septum - blood does not travel from one atria to the other
• Discovered that there are three parts to the sternum - Galen believed there were seven

William Harvey - Started comparing animal circulatory systems to human ones in 1615

• Discovered that there was too much blood in the body for it to be continually made in the liver and burnt, as Galen thought
• Described the heart as a pump,forcing blood around the body through the vessels
• Also explained the differences between viens and arteries, building on the work of Erasistratus