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

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They say in space, no one can hear you snore.

Of course, they also can't hear you finding doomsday devices at their planets when you wake

up to find your galaxy has been colonized by upstart apes while you slept. So today we are returning to the Alien Civilization series to explore the concept

of civilizations which spend a lot of time of sleep or hibernating.

This is one of the more common explanations we see for the phoey paradox in science fiction,

as it explains a galaxy which is full of some ancient alien

menace, but in such a way that we can somehow also exist to get in a fight with them.

Well you would normally expect is for them to have crushed us before we ever discovered

fire, let alone rocketry. If on the other hand they go dormant for a millennia at a time,

waking sporadically, this works better and also better matches with our current observations of the galaxy, which is to say it seems to be fairly empty of enormous and powerful alien civilizations.

We can see examples of this scenario everywhere from games like Mass Effect with the Reapers, the ancient

shadows and volons of the science fiction show Babylon 5, or the inhibitors from the novel

Revelation space, as well as a number of other examples.

Indeed, it's a fairly central concept of the cosmic horror genre of fiction pioneered by

folks like H.B. Lovecraft, which often has

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