Abstract

That life probably exists on other bodies in the universe is now a commonplace. That intelligent life exists elsewhere in the universe--taking for granted its presence on earth--is a widespread hope. Scientific efforts are under way, including space probes, special observations, and broadcast programs, in the systematic search for extraterrestrial intelligence. The question naturally arises whether other human beings are somewhere out there. Fresh avenues of philosophic reflection are opening concerning ethics, theology, and the metaphysics of being human. Imagination has been abundantly working over such issues extraterrestrially. Science fiction has run worlds away from science fact. Surrounded by yearning, fantasy, and popular culture, we need to clarify the intellectual grounds for work on extraterrestriality. The topic of other worlds and other intelligent life is an ancient and recurrent theme in great world cultures, including the Western tradition.