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.

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In recent centuries, we've had an avalanche of new technologies developed, and yet

none eclipsed the impact fire has had on our civilization.

But could a civilization arise without fire?

No. But could a civilization arise without fire? I recently completed an episode on the Fermi paradox asking if technology might be a good

deal less likely to develop than we might expect, and it got me thinking about possibly

the other direction that it's near inevitable to develop

once these species has sufficient technology.

This is our usual basic assumption that anyone clever enough to invent something will likely

be around those clever enough to see its usefulness and replicate and improve the design.

Not always, but occasionally, and more often than they'd discard something they knew was

useful, so you'd expect any clever critters from our ancestors to aliens on some other world

to eventually accumulate more technology.

In that episode, rare technology, we challenged that assumption, and a point I raised there

was that it seems

like humanity has had fire for around a million years, but took considerably longer

to use it for cooking food or fire sharpening sticks into spears. Indeed, it was only relatively

recently that we started using it for making ceramics or metals. 99% of the time we had

...