This Living on Earth transcript gives a concise look at the view of future longevity outlined by Ray Kurzweil in Fantastic Voyage: "there are three bridges, to dramatically extending our life - to radical life extension. ... only 10-15 years from now [we'll] have bridge two which [is] the full-flowering of the biotechnology revolution where we'll have the means of re-programming our own biology. ... health and biology and medicine are becoming information technologies, they are subject to what I call the 'Law of accelerating returns' which is this doubling of the power of these technologies every year. ... Bridge Three is nanotechnology. ... within about 20 years we will have fully reverse-engineered biology. We will have the means through biotechnolgy and nanotechnology to fix anything that goes wrong - ultimately at the cellular level and at the molecular level - with nanobots going inside our body and fixing each cell as something goes wrong. And that would really enable us to live indefinitely - it's a little bit different than a guarantee, I mean you could end up in an explosion somewhere or something. But it will really extend our human longevity indefinitely." I'm amongst those who think Kurzweil's projections are aggressive - but only by a decade or two.