Our Backup Planet

“Every sensate being we’ve encountered in the universe so far—from dogs and humans and mice to turtles and spiders and seahorses—has evolved to suit the cosmic accident that is Earth. The notion that we could take these forms, most beautiful and most wonderful, and hurl them into space, and that this would, to use Petranek’s formulation, constitute “our best hope,” is either fantastically far-fetched or deeply depressing.”

“As Impey points out, for six decades we’ve had the capacity to blow ourselves to smithereens. One of these days, we may well do ourselves in; certainly we’re already killing off a whole lot of other species. But the problem with thinking of Mars as a fallback planet (besides the lack of oxygen and air pressure and food and liquid water) is that it overlooks the obvious. Wherever we go, we’ll take ourselves with us. Either we’re capable of dealing with the challenges posed by our own intelligence or we’re not. Perhaps the reason we haven’t met any alien beings is that those which survive aren’t the type to go zipping around the galaxy. Maybe they’ve stayed quietly at home, tending their own gardens.”