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

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

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This episode is brought to you by Brilliant.

It has often been a common belief that our world was alive, a superorganism, or deity.

Could that be true?

And if so, might intelligent technological life forms, flying spaceships be how planets reproduce.

Earlier this year, a famous chemist and futurist James Lovelock died at the impressive age of 103.

Lovelock also had an impressive amount of work, both Neotorm and Speculiv, that he leaves

behind on everything from cryopreservation to geoengineering and worked for MI5, the British

Security Service for decades, where he was described as basically Q in the James Bond films.

He is probably best known for the Gaia hypothesis, also known as the Gaia principle or paradigm,

which comes in a number of variations these days but can be summed up quickly and mostly

accurately as the notion that Earth itself is alive and self-regulating, a type

of superorganism, arguably similar to how humans themselves have countless small cells and unrelated

organisms inside us, that life on Earth, its biosphere, in conjunction with its other

spheres like the atmosphere and hydrosphere, have regulated feedbacks

to keep Earth optimal for life to continue. Such being the case, we might extrapolate

that it happens on other planets or the exact opposite, that it is a near unique property

of Earth's emergent biosphere and the reason the universe doesn't seem to have ancient

alien empires sprawling

...