The Great Filter — Are We Almost Past It?
Robin Hanson · 1998
"Given that we see no evidence of any other intelligent civilization in a universe old and vast enough to have produced many, some 'Great Filter' — an improbability barrier somewhere between lifeless matter and galaxy-colonizing civilization — must exist, and the crucial open question is whether humanity has already passed it or still has it ahead."
This essay is Hanson's contribution to the Fermi paradox: if the universe is so old and vast, where is everybody? His framing: think of the path from dead matter to a civilization expanding across the galaxy as a sequence of hard steps — the origin of life, the jump to complex cells, the emergence of intelligence, the emergence of technological civilization, civilization surviving its own technology, among others. Since we observe zero visible galaxy-spanning civilizations anywhere, at least one of these steps must be extraordinarily improbable, a filter that almost nothing gets through.
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Are You Living in a Computer Simulation?
"At least one of three propositions must be true: civilizations almost never reach the technological stage capable of running ancestor-simulations, or those that reach it choose not to run them, or we are almost certainly living inside a simulation ourselves — and there's no principled way to rule out the third."