The Renaissance: New Ideas Begin to Challenge the Old (c.1500-c.1700)

The Renaissance (roughly 1400-1600) brought a spirit of enquiry — scholars began questioning ancient authorities and observing the world directly. In medicine, this gradually challenged the dominance of Galen and the Church.

Andreas Vesalius (1514-1564)

Vesalius was a Flemish physician who did something radical: he actually dissected human bodies and checked whether Galen was right. In 1543, he published On the Fabric of the Human Body (De Humani Corporis Fabrica), one of the most important medical books ever written. He proved that Galen had made over 300 errors — because Galen had dissected animals, not humans.

But Vesalius only improved anatomy — he did not explain how the body worked or what caused disease. Progress was slow because challenging Galen was still seen as dangerous and disrespectful.

William Harvey (1578-1657)

Harvey was an English physician who, in 1628, published proof that blood circulates around the body — pumped by the heart. Before Harvey, doctors believed blood was constantly being made in the liver and consumed by the body. Harvey showed this was impossible (there would not be enough blood) and used experiments to demonstrate circulation.

Harvey's discovery was important but did not immediately change medical practice — knowing how blood circulates did not tell doctors how to cure disease. The gap between scientific discovery and practical treatment remained huge.