So there must be another reason why we only conceive of extraterrestrials as humans. And I think the answer is that we are, in reality, terribly frail animals. And we don’t like to be reminded of how frail we are—how delicate the balances are inside our own bodies, how short our stay on Earth, and how easily it is ended. So we imagine other life forms as being like us, so we don’t have to think of the real threat—the terrifying threat—they may represent, without ever intending to.”
