Editor's note: This is the introductory article for the September 2010 special issue "The End".

Once again, the world is about to end. The latest source of doomsday dread comes courtesy of the ancient Mayans, whose calendar runs out in 2012, as interpreted by a cadre of opportunistic authors and blockbuster movie directors. Not long before, three separate lawsuits charged that the Large Hadron Collider would seed a metastasizing black hole under Lake Geneva. Before that, captains of industry shelled out billions preparing for the appearance of two zeros in the date field of computer programs too numerous to count; left alone, this tick of the clock would surely have shaken modern civilization to its foundations.

You might think that the enterprise of science, with its method and its facts, would inoculate us against the most extravagant doomsday obsessions. But it doesn’t. If anything, it just gives us more to worry about.

Some of the most fervent and convincing doomsayers, after all, are scientists. Bill Joy, co-founder and former chief scientist of Sun Microsystems, has warned that of out-of-control nanobots could consume everything on earth. Astronomer Royal Martin Rees has publicly offered a bet that a biological catastrophe—accidental or intentional—will kill at least one million people by 2020 (so far, no takers). Numerous climatologists sound the alarm about the possibility of runaway global warming. They all stand on the shoulders of giants: British economist Thomas Malthus predicted in the 19th century that the rise in population would lead to widespread famine and catastrophe. It never happened, but that didn’t stop Stanford biologist Paul R. Ehrlich from renewing the warning in his 1968 book The Population Bomb when he predicted that global famine was less than two decades away. Catastrophe didn’t arrive then, either, but does that mean it never will? Not necessarily. Still, people often worry disproportionately about disasters that are unlikely to occur. 

Science may be a culprit, but it also offers some explanation for why we can be so fearful. Some researchers think that apocalyptic dread feeds off our collective anxiety about events that lie outside our individual control. The fear of nuclear war and environmental decay that gripped the nation in the 1960s was a big factor in the rise of the counterculture, says John R. Hall, a sociologist at the University of California, Davis, and author of Apocalypse: From Antiquity to the Empire of Modernity. In this decade, civilization has suffered through even more fundamental threats. “After events like 9/11 and the Great Recession, as well as technological disasters like the BP oil spill, people begin to wonder—not just people who are fringe zealots or crazies—whether modern society is any longer capable of solving its problems,” Hall says. If the world appears to be going to hell, goes the thinking, perhaps that’s just what is happening.

The impulse is partially a consequence of our pattern-seeking nature—we are, after all, creatures of the savanna, programmed to uncover trends in the natural world. It is in our nature to weave a simple story from a complex set of data points. (In recent years this tendency has been amplified by news media that are very good at turning complex events into cartoon crises.) The desire to treat terrible events as the harbinger of the end of civilization itself also has roots in another human trait: vanity.

We all believe we live in an exceptional time, perhaps even a critical moment in the history of the species. Technology appears to have given us power over the atom, our genomes, the planet—with potentially dire consequences. This attitude may stem from nothing more than our desire to place ourselves at the center of the universe. “It’s part of the fundamental limited perspective of our species to believe that this moment is the critical one and critical in every way—for good, for bad, for the final end of humanity,” says Nicholas Christenfeld, a psychologist at the University of California, San Diego. Imagining the end of the world is nigh makes us feel special.

Our fears of the apocalypse may in the end mirror the most fundamental fear of all: fear of our own mortality. It is all of a piece—death, the dissolution of our people, the extinction of our species. Regardless of how we feel about it, flux is the nature of the world, and endings are an inescapable—and often overlooked—part of life. That is why we chose to devote the lion’s share of this issue of Scientific American to the theme of endings. We look at the chance that civilization will fall to pandemic or asteroid, to the loss of indigenous knowledge spread among the cultures of the world, to the declining resources that our planet will struggle to provide.

Some of these endings are more probable than others. Some, such as the end of time, are downright paradoxical. We start our journey, though, with a look at the inevitable—the private end that we will all have to face and our efforts to forestall it.