Physicist Paul Davies: “I think it very likely—in fact inevitable—that biological intelligence is only a transitory phenomenon, a fleeting phase in the evolution of the universe. If we ever encounter extraterrestrial intelligence, I believe it is overwhelmingly likely to be post-biological in nature.” Key word: extraterrestrial. You can slot Grey automatons into that niche. However, when it comes to "beings" of a more spiritual or ethereal nature, then the post-biological misnomer doesn't cut...