This is an IHeart podcast.

Welcome to Stuff to Blow Your Mind from How StuffWorks.com.

Hey, welcome to Stuff to Blow Your Mind.

My name is Robert Lamb.

And I'm Julie Douglas.

In this episode, we're talking about walls, which sounds a little big, and it is a big topic, because we live in this world of walls.

All around us, we have walls that we've erected, walls that are physical, walls that are made of stone, that are made of wood, walls that are legal walls, walls that

are mental, walls that are composed just of ideas, ideas of legacy, ideas of division.

Hidden walls, walls naked to the eye, firewalls, censorship.

With any situation with a wall, you have an outsider and you have an insider.

Generally, when we're contemplating walls, we're on one side of the other.

I guess it's possible to stand on the top of the wall, but that's a different situation.

It's a precarious position to be in, right?

You don't want to straddle the wall.

But this is one of the oldest ideas really in human civilization.

We've been building physical walls to protect cities and towns for ages.

Walled cities are one of the earliest symbols of civilization. How do you protect a settlement against

marauders who are using their horses to try and steal your agricultural excess? And in fact,

the Chinese word for a city and walls is the same, Ching, which I found

is interesting, because that's how important walls were in the emergence of cities in Chinese

history.

Yeah, and if you guys haven't already figured out, we are seriously talking about walls today,

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