Harvey was the first person to actually put all of the information together and come up with a believable theory, there were presumably many other doctors at that time, attempting to discover the anatomy of the human body, though through his medical background (trained at the best universities), his unstoppably character and belief in himself Harvey managed to persuade many people, though it wasn’t until later when the microscope was used that they found capillaries which Harvey predicted existed.
All of the four top doctors, had many dead human bodies to work on, this helped them actually see what was happening inside the body, unlike Galen who dissected apes, animals and human bones. Harvey’s test and experiments gave him the prove that was required to allow his theory to become established. Harvey out of all of the Renaissance doctors experimented the most giving him more evidence (presumably because he guest that most people would not believe it). Harvey dissected humans and cold-blooded animals, cold-blooded animals hearts moves much slower than a humans, which move too fast so Harvey could not see the valves moves or how the heart muscles moved. With the cold blood animals such as frogs he carefully watched numerous times and drew pictures and compared it to the human heart. Now Harvey could see exactly how muscles of the heart moved, with these experiments it gave Harvey more medical knowledge about the heart than any other person at that time. Harvey carried out other tests such as pushing thin rods down the veins, he found that the blood built up behind the rod, and did not go back to where it came from. This proved that the blood flowed in one way, no one had actually discovered much about the movement of blood before; Harvey had now undeniable proof that the blood flowed in one direction. Carrying on from Frabricius’s discovery of the valves, Harvey decided to experiment on them, he tried moving liquids past them, but to no avail, the valves were stopping them:
“He tried to pump liquids past the veins but he could not do so”
(Medicine and Health through time by Ian Dawson and Ian Coulson)
Harvey now was attempting link all of the parts together of the heart and was trying to figure out how they actually work and what they did. At that time people believed that new blood was constantly being made at a high rate, it was believed that the blood was burnt off. Harvey decided to actually calculate how much blood the heart moved at one time, he also calculated how much blood was in the body. This helped him disprove the theory that the blood was burnt off; it was in fact being reused and constantly moved around the body passed the lungs where it was oxygenated, by moving around the body it allowed all of the organs to be supplied with blood. Harvey suggested that there must be smaller blood vessels so small that you could not see them with the human eye:
“Between the arteries and veins there are tiny blood vessels called capillaries which would carry the blood. They are too small to be seen with the naked eye; So Harvey could not prove that they existed.”
(Medicine and Health through time by Ian Dawson and Ian Coulson)
Out of all his ideas, Harvey proved that the capillaries existed so he had to just theorize about them. It was not until later on when microscopes where invented that his theories about them were finally proved. All of Harvey’s information has been further proven correct, later on in the years.
In my Opinion Harvey contributed the most medical knowledge in the Renaissance period mainly because he discovered the most and was able to get his ideas heard and he proved them. Whenever Harvey disagreed with other doctors or proved them wrong, he would always give strong passionate arguments; he would explain clearly why and how he reached that conclusion and why the other theory was no longer valuable (incorrect). Harvey also published a book, which sold many copies; inside it had detailed drawings allowing the reader to understand how he got to that conclusion. Out of the medical knowledge contributors, Harvey found the most evidence to his discoveries, he didn’t only discover things such as there were no holes in the septum but he actually found out why they did what they did. Harvey added all of the previous information together and with his own made new discoveries, which are accepted today. He also managed to stop treatments such as bleeding which he proved actually did not help in most cases, Harvey was very open to new suggestions as well, such as Pare’a Ligatures, which he used. Evan if Vesalius had not first went against the church and Galen, because of Harvey’s strong character and belief in himself he would still would have spoken out. Though Harvey could never experiment on live humans or normal dead humans (non criminals), they were the same inside as any other person so it didn’t actually matter. The sheer mass of what Harvey found is far greater than any other contributor to medical knowledge in the Renaissance period.
