Flemish anatomist Andreas Vesalius (1514–1564) published De Humani Corporis Fabrica in Basel in 1543, the most comprehensive and accurate atlas of human anatomy produced to that point. Based on systematic human cadaver dissection, it corrected hundreds of errors in Galen's anatomy — which had been derived from animal dissection — overturning 1,400 years of accepted medical doctrine. Richly illustrated by artists from Titian's studio, the work established direct observation over inherited authority as the basis of anatomical knowledge and helped lay the groundwork for modern scientific medicine.