Seventy-one students graduated from Stow Public High School in June, 1947. Fifty-two of them, or 73%  are still alive. Yesterday, on the way home from the reunion, it occurred to me that lifestyle, as well as chance and genetics, must play a role in the generation of life expectancies. Some unfortunate individuals have had shortened life-spans because of inherited disabilities such as diabetes or hyperlipodemias (conditions that should soon be correctable). Others are felled by accidents, or similar acts of chance...  which brings us to life styles. To some degree, there must be attrition among those who have embraced unhealthy life styles. I don't know what the average life expectancy is among an average group of 18-year-old high school graduates, but if you subtracted those with life-shortening conditions and those who practice unhealthy health habits (e. g., living on junk food) from the total group, you would probably get a significantly higher life expectancy than you would for the group as a whole. 
    The good news is that if the average life expectancy at birth is somewhere in the seventies, the average life expectancy at 18 would be, perhaps, two or three years higher than that. If you subtracted out those poor folk who have a predisposition toward an early demise, and those who don't strive to maintain good health, the remainder probably has an extended life expectancy in the eighties or nineties. With this go advances in medical science that may be responsible, in part, for the fact that life-spans are rising 1/4th year per year with no end in sight. Twenty years from now, life expectancies should be 5 years greater than they are today. Forty years from now, life spans would be 10 years greater than they are today. And 80 years from now, if we can simply extrapolate this trend, they should be 20 years greater than they are today. . . if you take care of health. (This ignores the advances that I think will take place in longevity research. This is based simply upon the extrapolation of current trends.) (One dark horse is a company that has been established recently by Harvard to bring to market the protein or proteins that bestows long lives on centenarians.)
    One influence might be our growing knowledge of regimens that tend to ward off cancer, and that protect against cardiovascular disease. Cures or preventives for Parkinson's disease and Alzheimer's disease will give a little boost to life expectancies. Ditto for other autoimmune diseases, such as lupus and multiple sclerosis. The discovery of a way to mimic the effects of restricted caloric intake would be a breakthrough in slowing the aging process.
    Of course, these gradual improvements in health and longevity have brought other problems in their wake. People are living longer, and no doubt, there are other people who don't want anyone to live longer than they have in the past (except, maybe, themselves when their turn comes). But it seems to me that the extension of youth-spans that has occurred over the 20th century has been a very positive thing. In 1900, the elderly had to live with their children and grandchildren, and that was not a happy situation for anyone. 
    Some members of our class may be expected to survive at least into their nineties, and more pleasantly than nonagenarians have had it in the past.
   It has been said repeatedly that the average life-span can't increase much beyond what tit is now, and that the maximum life-span can't exceed its present maximum value.
    In the 18th century, scientists had shown that if a vehicle went faster than about 20 miles an hour, its driver/passengers would die (of asphyxiation?).
    My grandparents were assured that Harvard's Dr. Simon Newcomb had shown that passenger-carrying, heavier-than-air flying machines were forever impossible.
   When I was a child, it was absurd to imagine that anything could ever be propelled into outer space. "What goes up, must come down. There's no air to push against out there. The temperature in the highest layers of the Earth's atmosphere is hundred of degrees Fahrenheit. You'd burn up if you reached them. Anyway, rockets just blow up and kill their creators. Look at that Max Valier fella'!.Even if you could build a rocket ship, and it worked, and didn't explode or burn out or like of that, it can't go faster than its exhaust. And even if you could make it take you into space, why would you want to go there? There's nothing out there! That's why they call it 'empty space'! And who would pay for it? Companies aren't going to invest money in something that has no payoff."