Think back to middle school. You're in biology class and the smell of formaldehyde wafts in the air.

You've just spent weeks learning about the vital organs from textbooks and lectures,

but now a little green frog has played lifeless before you. You're about to participate in that

familiar right-of-passage, the dissection. The exercise may feel kind of archaic,

but how do you really know something exists without seeing it for yourself? To truly understand

something after all, sometimes you just need to open it up, analyze it down to its distinct parts,

tease apart the things that matter from the things that don't. See with your own eyes,

just how interconnected everything is.

Dissection is about learning, about getting inside of something to understand it better.

And with all we hear about health these days, whether in the news or on social media or from

wellness gurus on TV, it's easy to miss the parts that matter. So it's time for some

dissection. Let's start at the beginning.

It's London. 1853. The city's just been transformed by the industrial revolution. Life is changing

fast. It's summer in the city, unusually hot. It's crowded. People are doing everything they can

to escape their tiny tenements. And there's something else. Death in the air. There's been an outbreak

of cholera. The epidemic is spreading fast. In the past week alone, in one neighborhood,

83 people were declared dead. Enter Jon Snow.

Yeah, not that Jon Snow.

We're talking about the OG doctor, Jon Snow. He wasn't king in the North, but he did take care

of the queen when she gave birth. And nobody knows it yet, but he's about to become king of public

health. But back to this epidemic. The big question on everyone's mind is how it's spreading,

because then maybe someone could do something about it. There are two competing camps. Camp 1,

...