He dissected human bodies himself and overturned 1,300 years of anatomy textbooks

In 1543 Andreas Vesalius published detailed anatomical drawings based on his own human dissections, showing that Galen's revered anatomy -- based on animal dissections, not people -- was wrong in hundreds of places. It refounded human anatomy as an evidence-based science.

— Andreas Vesalius, De Humani Corporis Fabrica — original treatise, 1543