Hello, SFIA audio listeners. In this month's Nebula exclusive, big alien theory,

we're asked at the reason alien civilizations might be rare is because most aliens are huge.

To hear it and every episode early and ad-free, plus hours of bonus content,

check out go.nebola.tv slash Isaac Arthur and use my code, Isaac Arthur.

The universe is a cold and hostile place, and may be inhabited by ruthless civilizations

or machine minds bent on destroying anything in their way.

Today we'll be looking at xenocide, which if you didn't already know is the alien equivalent

of genocide, where you wipe out an entire intelligent species.

This term was popularized by Orson Scott Carld in his epic science fiction series built

around the original two novels, Ender's Game and Speaker for the Dead, which deal with

a protracted war between humans and an alien civilization

and its aftermath. The third book is titled Zenocide, and it's also the epitat human civilization

gave the main hero of that war centuries after Humani won and reconsidered the ethics of their actions.

As you might guess, the book explores themes of if and when it can ever be acceptable to wipe out an alien civilization,

and the book pulls few punches, starting with the title and the obvious allusion to genocide.

That term itself was only coined in 1944, with World War II very much in mind.

And the definition is a bit vague or debatable, but for today, we'll just go with the deliberate

and systematic destruction of a national, ethnic, racial, or religious group.

That's the first definition that came up on the Internet for me, which is the sole reason

for its specific selection.

Etymologically, Geno comes from the Greek genus for race or tribe, and side is to kill, and

Zeno means foreign or alien.

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