From GOOD: "How long do you think you'll be around for? Ninety years? One hundred and twenty? Aubrey de Grey, a biogerontologist and Cambridge-trained Ph.D. who studies aging, thinks we could engineer techniques that reverse the wear on our bodies by replacing lost cells in our bones and hearts and even tweaking the cells themselves to prevent their degeneration. If de Grey is right, these therapies could help us live for hundreds - if not thousands - of years. ... In my view, we probably can't [slow down aging] much at all. All we can do is reverse it. Yes, I know it seems paradoxical that reversal would be easier than slowing, but if you think about it, that's what we do with simple manmade machines such as cars or airplanes: We do periodic repair and maintenance. That's how we'll delay the ill health that aging eventually causes. ... It's impossible to say for sure [as to what social changes will result from radical life extension], but I think the changes would actually be rather slight. We don't make career or life choices today in early adulthood on the basis of only having 50 more years to live."