One of the many cognitive failings of human beings is that we tend to think tomorrow will be a lot like today. As a day to day heuristic, this is actually pretty sensible; if you predict that tomorrow's weather will likely be quite similar to today's weather, you'll be right most of the time. Except, of course, when you're wrong. In the 1930s and 40s, Europe's Jews assumed that each day would be much like the previous day, and they were right, by and large -- but a whole series of days that are only marginally different from the previous day can bring you, with surprising speed, to some terrible places.
Setting cognitive errors aside, we do not, as a nation or as a species, have much basis for assuming that things will keep on getting better. For that matter, we have little basis for assuming that things that are crummy now will get fixed, or even stay only as crummy as they are now (as opposed to getting a whole lot crummier). To keep things in perspective, the cataclysm of World War II was only 70 years ago. World War I was only a century ago. Why would anyone imagine that such catastrophes -- still alive in the memories of older Americans -- can't happen again? Do we really think the human species has evolved somehow in the last few decades?
Steven Pinker thinks so: In his 2011 book, The Better Angels of Our Nature, he argues that human violence is in decline, at least if viewed over the last few centuries. Whether he's "right" or "wrong," however, his argument is, for present purposes, largely irrelevant. Even if humans are somewhat less nasty to one another than they used to be, the complexity of our world has increased exponentially, and our ability to inadvertently mess the world up has similarly increased.
Take your pick of anthropogenic apocalypse scenarios. You don't like enslavement to intelligent toasters? Fine. There's always nuclear annihilation, still a distinct possibility. Or deadly epidemics spread by bio-engineered germs (or naturally occurring germs whose transmission is aided by air travel and so on), or a meltdown of the global financial system that will make 2008 look like a boom year, or climate change that submerges coastal cities, or cyberattacks that cause catastrophic infrastructure failure. (Richard Posner, who will certainly be the only law professor to survive the apocalypse, offers lurid details of these scenarios and many more in his 2005 book, Catastrophe).
Ah, you're still scoffing. "Ha," you say, "People have been predicting catastrophes for decades -- remember Silent Spring? Acid Rain? Overpopulation? SARS? Swine flu? Betcha all those doomsday prophets feel silly now!"
I bet they do feel silly. I feel silly whenever I contemplate buying more than a few extra flashlight batteries. But once again, feeling silly doesn't mean you're wrong to worry. Black swans may yet appear, and low-probability/high-consequence events may yet happen.
But don't take my word for it. Consider this recent report from Chatham House, which is not known for apocalyptic hysteria: "Current contingency planning often assumes the return of the status quo ante after a crisis. But this approach may be inadequate in a world of complex economic and social risks, especially when combined with slow-motion crises like climate change and water scarcity. Slow-motion crises such as these build over many years, but are likely to result in a higher frequency and greater severity of shocks....We have always had risks to face. Two things seem to have changed today: the frequency of catastrophes seems to be increasing; and our population remains relatively unaccustomed to the magnitude and probability of the risks we are currently facing." Adjusting for the dryness of British think-tank reports, this is a hysterical cry for help.
Even if we think catastrophic events are extremely unlikely to occur, it makes sense to start thinking about how to mitigate risks. In the words of philosopher Huw Price, co-founder of the new Centre for the Study of Existential Risk at the University of Cambridge, shouldn't we all be trying to "shift some probability from the bad side to the good"?
Yup. I'm ready to pledge my support for the project of mitigating existential risks.
And in the meantime, I might even buy some more flashlight batteries.