Doctor Eternity

Grossman liked what he heard. Here was the concise, orderly and seemingly logical solution to mortality that he had dreamed of. To him, the idea of man merging with computer didn't sound crazy at all — in fact, he already saw it occurring all around him. "We have already begun to enter this phase of transhumanism," he says. Just look at his dad, who is on kidney dialysis: "My father is part human, part machine."

The doctor and the inventor hit it off. "He was the kind of doctor I was looking for," says Kurzweil. After all, Kurzweil's calculations peg the occurrence of the singularity at around 2045, at which point they'll both be nearing 100. In other words, Kurzweil has foreseen the future; now Grossman must keep them alive to see it.

The blood tests and bowls of ice water are just the beginning of my longevity evaluation. A few hours in, Diane, armed with a disposable razor, tells me to take off my shirt. They're going to cover me with electrodes and put me on a treadmill, but first they need to make sure the electrical conductors make contact with my skin. Soon the floor is covered with hairballs, and my torso is dappled with clean-shaven swaths. "You might just want to wax the rest," Diane advises before moving on to step two.

"What's that called?" I ask about the viscous liquid she's squirting onto a paper towel. "Liquid sandpaper," she says, then demonstrates why, vigorously rubbing the abrasive goop on the spots she shaved to remove my uppermost layer of skin. "That wasn't so bad," I manage unconvincingly when she's through, my red and blood-dappled chest heaving. "Well," she replies, "I haven't put on the alcohol yet."

Diane takes me to a small gym in another part of the office building for the treadmill test. When it's over, she suggests I clean up in a nearby bathroom. I walk in sweaty and shirtless, electrodes plastering my raw, half-shaven chest — and come face to face with a man washing his hands at the sink. I try to act casual.

When I finally meet with Grossman, he explains that all of these assessments are to determine my age — not my chronological age, but my biological one. He wants to know just how well my body has stood the test of time and what I can do to improve upon that. His method for doing so combines what he believes are the best practices from conventional and alternative medicine into a single, comprehensive procedure for detecting and preventing any and all ailments. He may sound like he's improvising, but as he's fond of saying, "Life is not a randomized, double-blind placebo-controlled trial. You only have one shot at it. So we make the best choices with the information we have."

Grossman and Kurzweil believe this sort of aggressive anti-aging strategy is the first of three bridges that will lead humanity to eternal life. The second bridge is the biotechnology revolution, a point in the next ten years or so when scientists will learn to control our DNA, turning diseases off with ease, not to mention cloning and regenerating our organs, developments that will dramatically increase life spans. The third bridge is the point at which nanotechnology and artificial intelligence allow humans to control their existence at the atomic level, the dawn of the singularity.

For years, the two fleshed out these ideas in e-mails sent back and forth from Grossman's office in Denver and Kurzweil's headquarters in Cambridge, Massachusetts. When they reached 10,000 missives, they figured they had enough for a book.

To figure out how far I am across bridge one, I'm left alone in a room in front of a computer. On the screen, a computerized woman runs me through one aptitude test after another to determine my biological age. I listen to high-pitched noises through bulky earphones to check my hearing. I hold a subtly vibrating box to gauge my touch sensitivity. I furiously punch computer buttons to demonstrate my muscle movement time. I eventually reach a memory quiz, during which the computer flashes lights in patterns that I have to repeat by pressing corresponding buttons, patterns that get increasingly difficult. It's just like that old electronic rhythm game Simon, at which I used to excel. Sure enough, I match the computer's pattern time after time, until a message flashes on the screen: "This is where I quit. Congratulations: You've beaten the computer!"

Grossman is impressed. "You redlined the computer," he remarks, something that only one other American and two Japanese patients have managed to do. The feat proves I'm doing fine, age-wise: The computer reports that I'm 28 years old biologically, a year younger than my chronological age. Not too shabby.

Searching for immortality has a dubious distinction: It's unquestionably the world's least successful occupation. This dreary track record hasn't stopped members of each succeeding generation to egotistically believe that they, unlike all the folks before them, will surely witness the conquest of death.

These days, the immense baby boomer generation, which has always gotten everything it's wanted, is now sauntering into its twilight years and has decided it wants everlasting life, too. It's no wonder then that products promising to make people look or feel younger have now ballooned into a $50 billion U.S. industry, or that the American Academy of Anti-Aging Medicine claims more than 20,000 member physicians from 100-plus nations.