A generation ago, humans eluded nuclear annihilation; with luck, we’ll continue to dodge that and other mass terrors. But now we often find ourselves asking whether inadvertently we’ve poisoned or parboiled the planet, ourselves included. We’ve also used and abused water and soil so that there’s a lot less of each, and trampled thousands of species that probably aren’t coming back. Our world, some respected voices warn, could one day degenerate into something resembling a vacant lot, where crows and rats scuttle among weeds, preying on each other. If it comes to that, at what point would things have gone so far that, for all our vaunted superior intelligence, we’re not among the hardy survivors?
The truth is, we don’t know. Any conjecture gets muddled by our obstinate reluctance to accept that the worst might actually occur. We may be undermined by our survival instincts, honed over eons to help us deny, defy, or ignore catastrophic portents lest they paralyze us with fright.
If those instincts dupe us into waiting until it’s too late, that’s bad. If they fortify our resistance in the face of mounting omens, that’s good. More than once, crazy, stubborn hope has inspired creative strokes that snatched people from ruin. So, let us try a creative experiment: Suppose that the worst has happened. Human extinction is a fait accompli. Not by nuclear calamity, asteroid collision, or anything ruinous enough to also wipe out most everything else, leaving whatever remained in some radically altered, reduced state. Nor by some grim eco-scenario in which we agonizingly fade, dragging many more species with us in the process.
Instead, picture a world from which we all suddenly vanished. Tomorrow.
Alan Weisman, The World Without Us (2007)