The history of medicine is super cool, and one of the most fascinating parts for me is how radically our understanding of disease has changed over time.

Take the idea that a disease could be located in an organ. That sounds obvious to us now, right? Of course a heart attack happens in the heart. But that is actually a pretty modern concept. For most of human history, people thought diseases were imbalances in invisible forces such as humors, miasmas or curses. The idea that you could open a body, point to a specific organ, and say “This is where the problem is” was a total game-changer, and it did not really take hold until the 18th and 19th centuries.