Extraterrestrial: The First Sign of Intelligent Life Beyond Earth

by Avi Loeb

Enrico Fermi was one of the giants of twentieth-century physics. Among his accomplishments is the development of the first nuclear reactor and, as he was instrumental in the Manhattan Project and the production of the first nuclear bomb, he can claim some credit for the prompt ending of hostilities with Japan at the conclusion of World War II. Toward the end of his storied career, during a lunch with his colleagues, Fermi raised a simple, provocative question: How do we explain the paradox that, given the vastness of the universe, the probability of extraterrestrial life seems high, yet there is no certain evidence for anything but terrestrial life? If life is common in the universe, he asked, “Where is everybody?” Over the years, many answers have been formulated. One is especially arresting and especially pertinent to the unfolding mystery of ‘Oumuamua and its implications for us. In 1998, the economist Robin Hanson published an essay titled “The Great Filter—Are We Almost Past It?” Perhaps the answer to Fermi’s paradox was, Hanson argued, that throughout the universe a civilization’s own technological advancement overwhelmingly predicts its destruction. The very moment when a civilization reaches our stage of technological advancement—the window where it can signal its existence to the rest of the universe and begin to send craft to other stars—is also the moment when its technological maturity becomes sufficient for its own destruction, whether through climate change o...