Eternal life has always been the stuff of myth, fantasy, or faith. But artificial intelligence expert and futurist Ray Kurzweil and physician Terry Grossman have a provocative message: that people alive today can make use of existing medical knowledge to extend their lives and remain healthy until a time, just decades hence, when advanced biotechnology will make "radical life extension" (a slightly hedged euphemism for living forever) feasible. It's an audacious claim, and the authors make a serious case for it in their new book, Fantastic Voyage: Live Long Enough To Live Forever.

No, it's not the Isaac Asimov science fiction classic, but the title is appropriate, since nanotechnology is likely to be a big part of the future of health care. While the book is, indeed, part futurist vision it's also part advocacy for "aggressive supplementation" and part general health guide. The split focus makes it a sometimes frustrating and even difficult read. For one thing, in order to back up their claims for nutritional supplementation, the authors provide quite detailed biochemistry. There's a reason most of us didn't become biochemists, and plowing through the hard science can be tough.

On the plus side, it shows they have a high opinion of their readers. And let's face it, without supplying the hard science behind "Ray & Terry's Longevity Program" they'd have a hard time being taken seriously by a public that's already saturated with confusing and contradictory health information.

In the authors' conceptualization,

the goal of extending longevity can be taken in three steps, or Bridges. This book is intended to serve as a guide to living long enough in good health and spirits - Bridge One - to take advantage of the full development of the biotechnology revolution - Bridge Two. This, in turn, will lead to the nanotechnology-AI (artificial intelligence) revolution - Bridge Three - which has the potential to allow us to live indefinitely...

Our core idea is that we now have the knowledge to determine where each of us is located in the progression of... [our] decades-long degenerative [biological] processes and reverse them... [emphasis added]

Although human ability to take command of the course of life and death is controversial, we believe that the ability to broaden our horizons is a unique and desirable attribute of our species.

That passage contains one of a very few hints that the authors recognize the importance of ethical issues in biotechnology. Kurzweil and Grossman do not pose or address the questions ethicists, philosophers and science fiction writers have been asking for a long time: what would be the psychological effects of living for hundreds of years? At what level of artificial enhancement might a person cease to be human (and who is to judge)? Can people with varying degrees of physical and mental enhancements maintain sociopolitical equality?