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Intelligent life can't be all that common because it's really rare on Earth and especially since we define ourselves to be intelligent. But in the eyes of an alien coming here who has the technology to make it here, they might observe us and conclude that there's no sign of intelligent life on Earth.

"Neil deGrasse Tyson's 'Cosmos'". "Here and Now" with Jeremy Hobson, kuow.org. March 6, 2014.
Intelligent life can't be all that common because it's really rare on Earth and especially since we define ourselves to be intelligent. But in the eyes of an alien coming here who has the technology to make it here,