01/22/2011 02:04 am ET Updated Nov 17, 2011

Will Our Species Survive Another Century?

Don't we have enough troubles without being told, especially by scientists, that humans may not survive another century? Frank Fenner, an Australian scientist involved in the global elimination of the smallpox virus, recently predicted the demise of another species within 100 years -- our own. (Fenner died last month at age 95.)

Other English-speaking scientists who have envisioned doom include, with various qualifications, Stephen Hawking (holder of Newton's chair at Cambridge), James Lovelock (Dr. Gaia) and Martin Rees (Astronomer Royal).

Most of us reject or ignore these messages: the men are old and perhaps confuse their own demise with that of the species; accomplishments in virology, astronomy, or biology do not confer prophetic power; academics are known to be less optimistic than (say) business people; no single person can solve our poly-problems but, as the English say, we'll somehow muddle through, perhaps as a result of technology unknown today.

Here on the other side of the Atlantic, we had Leó Szilárd (a nuclear physicist) imagining that dolphins start a movement to save the humans, and more recently Bill Joy (a founder of Sun Microsystems) explaining in Wired magazine "why the future doesn't need us." I'm leaving aside the list of climate scientists who foresee a world unlike the one on which civilization developed.

Just for purposes of a thought-experiment, assume they are right. Assume further that, even if authorities acted intelligently, with foresight and courage, it's too late to save the species:

How then should we live?

Even if most people would carry on as before until a collapse happened and they panicked, what about those who now understand and accept the prediction? Some might party, as if they were in a fraternity, all classes have been called off, and a supply of intoxicants were assured. Some might, like evacuees from the black plague in Boccaccio's "Decameron," tell stories about how it used to be, how humans behave. Some might belatedly try to adapt to worsening conditions, in the hope of being among the last survivors: "off the grid."

At least since the Cuban missile crisis of 1962, I've been concerned along with many others about an accidental nuclear exchange, using "accidental" in a broad sense. When I was bending the ear of a Manhattan friend who was director of a foundation, she asked, "Why should I worry? Living in New York I'd die immediately."

At the time I judged this to be a selfish attitude: what about the future of civilization? (This judgment led me to taking a job in the 1980s to help end the Cold War, the kind of job you hope to work your way out of.)

But the premise of our thought experiment is that it's almost surely too late to prevent the demise of the species. How should we live? Some might try anyway to define problems and solve them: you never know what surprises may emerge.

A friend said the only sane response would be to celebrate and exemplify the best that the species has been and done. In this context, she says, recent talk about "the gift culture" is relevant. What if our default question were no longer, "what's in it for me?" but rather, "what can I give?" While she knows that people can be greedy, she raises an eyebrow about our trust that "the invisible hand" will automatically transmute individual greed into social welfare, rather than this mysterious hand, as she says, picking our pockets.

Okay, that's one response. What's yours? If you expected the species to expire within a century, would you have children? Stay at your job? Work on any of the issues that fill our mailboxes with appeals for funds? Or what?

Stephen Levine wrote a book, "A Year To Live." His point was that, even in the absence of a life-threatening disease, it's a good exercise to act as if death is coming in only 12 months, as if this year is your last. In his experience, this exercise is not morbid, but life-enhancing.

I want to make clear that this blog is not predicting anything, but is rather proposing a thought-experiment in the spirit of Levine. What if the death of our species were less than a century away?