Why Mass Extinctions Make Intelligence Vanishingly Rare in the Universe: The Charmed Life Hypothesis

Mass extinctions may explain why intelligent life is rare in the universe. On many worlds catastrophes may wipe out complex life, or sterilize the planet, preventing the evolution of intelligence. We may have gotten incredibly lucky to have a planet that remained habitable for 4.5 billion years. I call this the Charmed Life Hypothesis, and it’s one of the most terrifying explanations for why we haven’t made contact with aliens. It's a counterintuitive idea because necessarily most of the evidence in favor of it can't be found by studying Earth's history, or we wouldn't be here. Earth's history shows an unbroken period of habitability extending back 4 billion years... but it could hardly be otherwise, or we wouldn't be here to see it. Numerous nonlethal mass extinction events- the asteroid impact that killed the dinosaurs, the Permo-Triassic extinction, Snowball Earth glaciations- failed to wipe out complex life, but this may be survivorship bias; only on planets where life survives the gauntlet of mass extinctions can intelligence emerge to study its history.