http://www.perlmonks.org?node_id=1172118


in reply to Re: Extraterrestrials haven't visited the Earth yet because:
in thread Extraterrestrials haven't visited the Earth yet because:

Not exactly. #2 is meant to cover the case where there is extraterrestrial life, but it never evolves to a human level of intelligence (or higher). i.e. we don't know if the emergence of life inevitably leads to technological capability.
  • Comment on Re^2: Extraterrestrials haven't visited the Earth yet because: