Ray Kurzweil, a futurist, predicts a world of conscious machines and greatly increased life expectancy.

JOHN TIERNEY ESSAY

Do you have trouble sticking to a diet? Have patience. Within 10 years, Ray Kurzweil explained, there will be a drug that lets you eat whatever you want without gaining weight.
Worried about greenhouse gas emissions? Have faith. Solar power may look terribly uneconomical at the moment, but with the exponential progress being made in nanoengineering, Dr. Kurzweil calculates that it’ll be cost-competitive with fossil fuels in just five years, and that within 20 years all our energy will come from clean sources.
Are you depressed by the prospect of dying? Well, if you can hang on another 15 years, your life expectancy will keep rising every year faster than you’re aging.
At least that’s Dr. Kurzweil’s calculation. It may sound too good to be true, but even his critics acknowledge he’s not your ordinary sci-fi fantasist. He is a futurist with a successful record of predictions and enough credibility for the National Academy of Engineering to publish his forecast for solar energy.
He makes his predictions using what he calls the Law of Accelerating Returns, a concept he illustrated at the recent World Science Festival in New York with a history of his own inventions for the blind. In 1976, when he pioneered a device that could scan books and read them aloud, it was the size of a washing machine.
Two decades ago he predicted that “early in the 21st century’’ blind people would be able to read anything anywhere using a handheld device. In 2002 he narrowed the arrival date to 2008. On May 29 at the festival, he pulled out a new gadget the size of a cellphone, and when he pointed it at the brochure for the science festival, it had no trouble reading the text aloud.
This invention, Dr. Kurzweil said, was no harder to anticipate than some of the predictions he made in the late 1980s, like the growth of the Internet in the 1990s and a computer chess champion by 1998. (He was off by a year - Deep Blue’s chess victory came in 1997.)
“Certain aspects of technology follow amazingly predictable trajectories, he said, and showed a graph of computing power starting with the first electromechanical machines more than a century ago. At first the machines’ power doubled every three years; then in midcentury the doubling came every two years ; now it takes only about a year.
Dr. Kurzweil has other graphs showing a century of exponential growth in the number of patents issued, the spread of telephones, the money spent on education. One graph of technological changes goes back millions of years, starting with stone tools and accelerating through the development of agriculture, writing, the Industrial Revolution and computers.
Now, he sees biology, medicine, energy and other fields being revolutionized by information technology. By the 2020s we’ll be adding computers to our brains and building machines as smart as ourselves, he says.
Dr. Kurzweil’s predictions come under intense scrutiny in the engineering magazine IEEE Spectrum . Some of the experts writing in the issue endorse Dr. Kurzweil’s belief that conscious, intelligent beings can be created, but most think it will take more than a few decades.
He is accustomed to this sort of pessimism . But if experts in neurology and artificial intelligence don’t believe his optimistic predictions, he says, that’s because exponential upward curves are so deceptively gradual at first.
“Scientists imagine they’ll keep working at the present pace, he said. “They make linear extrapolations from the past. When it took years to sequence the first 1 percent of the human genome, they worried they’d never finish, but they were right on schedule for an exponential curve. If you reach 1 percent and keep doubling your growth every year, you’ll hit 100 percent in just seven years.