Intelligent Life May Have Appeared in the Universe Billions of Years Ago

[W]e might expect intelligent life and technological communities to have emerged in the universe billions of years ago. Given that human society is only a few thousand years old, and that human technological society is mere centuries old, the nature of a community with millions or even billions of years of technological and social progress cannot even be imagined. ... What would we make of a billion-year-old technological community?

P. C. W. Davies, Are we alone? (1995-06-23)

• alien life
• extraterrestrials