With all due respect to the true heir of the Iron Throne, the real John Snow was the scientist who achieved a great scientific breakthrough – he found out that we better not shit where we eat… or drink!
Yap, this back then new and exciting revelation made him the father of modern epidemiology.
Snow (1913-1958) lived in a time when cholera outbreaks were prevalent in the United Kingdom and were its top killer. Snow challenged the then-dominant Miasma Theory that suggested that cholera is caused by a noxious form of ‘bad air’.
His observation and scrutiny of evidence led him to deduce that the main source of the cholera epidemic was the foul water supply.
Cholera is, by large, circulated when an infected person’s feces contaminated food or drinking water. Yes, that is why mom always insists we wash our hands before we eat. Apparently she read all of Snow’s studies.
Bonus Fact: even to date cholera claims 120,000 lives every year. Throughout history, it is responsible for at least tens-of-millions of deaths, probably much more.