The first real dissections for the study of disease were carried out about 300 BCE by the Alexandrian physicians Herophilus and Erasistratus, but it was the Greek physician Galen of Pergamum in the late 2nd century CE who was the first to correlate the patient’s symptoms (complaints) and signs (what can be seen and felt) with what was found upon examining the “affected part of the deceased.” This was a significant advance that eventually led to the autopsy and broke an ancient barrier to progress in medicine.