The idea of achieving radical life extension - living healthily not just for additional decades, but centuries or even longer through advanced medical technology - by successive steps is far from new. It's been a part of modern transhumanist discussions of healthy life extension for as long as those discussions have been taking place. The concept is very simple: if a new technology can give you 20 extra years of healthy life, then you could benefit from the end results of another 20 years of further medical research and development. The application of those end results will extend your healthy life span again, and so it continues. If medical technology advances rapidly enough - a big if - then your life span will no longer be limited by disease and aging; you will have beaten the curve.
For all that this concept has been around for a long time, it has suffered from a lack of good packaging for public consumption. Ideas have to have a certain shape to make progress in our idea-saturated culture. This a terrible shame - it's a great concept, very intuitive and attractive once grasped. It's certainly simple enough to spread widely if explained well, but take a look at one of my attempts back in 2004:
If regenerative medicine can give us 30 extra years of healthy life, then we will have time to develop working medical nanotechnology - it will be 2050 already! While regenerative medicine is largely a matter of manipulating existing proteins, genes and cellular mechanisms to heal, nanomedicine promises to use tiny machines to do all that far more efficiently and with greater degrees of control and effectiveness.
Beyond nanomedicine...well, nanomedicine will give us many healthy years to think about what comes next.
This, in a nutshell, is the bootstrapping process: extending healthy life span faster than we age. It's a realistic goal for modern science. Not an easy goal, but a realistic one.
The bootstrapping metaphor didn't quite work. Elsewhere, and more recently, Ray Kurzweil and Terry Grossman use the metaphor of bridges - "a bridge to a bridge to a bridge" - in Fantastic Voyage. Biomedical gerontologist Aubrey de Grey and some other healthy life extension advocates have settled on "actuarial escape velocity":
An interesting scenario was thus unexplored: that in which mortality rates fall so fast that people's remaining (not merely total) life expectancy increases with time. Is this unimaginably fast? Not at all: it is simply the ratio of the mortality rates at consecutive ages (in the same year) in the age range where most people die, which is only about 10% per year. I term this rate of reduction of age-specific mortality risk 'actuarial escape velocity' (AEV), because an individual's remaining life expectancy is affected by aging and by improvements in life-extending therapy in a way qualitatively very similar to how the remaining life expectancy of someone jumping off a cliff is affected by, respectively, gravity and upward jet propulsion.
We're all searching for the right handle, the right hook by which this concept will spread far and beyond the cultural conversation about healthy life extension. People respond very positively to the idea of radical life extension via actuarial escape velocity - it's a great meme for encouraging support and understanding of our goals. We need to work on the packaging and delivery, however.