If the average human lifespan was 40 years, how would you live your life differently?Well, I would have retired at the age of 30, so I'd have plenty of time to enjoy that last decade or so. To be honest, I don't know that I would do much differently at all. I have no real regrets as I look back on my life at this point. I don't see the need to change that view just because my lifespan has been cut in half. Things that happen happen for a reason, whether it happens over the course of 40 years, 80 years or 120.