That's irrelevant for two reasons. First, the life expactancy for someone who is x years old was higher than 38, which is the life expectancy at birth. Second, there's no obvious rule of nature that people will accomplish amazing feats at an earlier age if their life expectancy is lower.
Third: That was the life expectancy at birth across society in general at the time, not the life expectancy of somebody fortunate enough to be able to go into academia.
Most of the people mentioned in this thread from that era in fact lived into their 70s or 80s (70 for Leibniz, 84 for Newton, etc). That might be a coincidence, but I suspect that reduced occupational hazards played a significant role.
Yes, and I recommend the article: it confirms that life expectancy was 38 and only 8% of people reaching adulthood lived to be 60.
The article is trying to say that life expectancy is reduced by high child mortality, but that's a pretty harsh adult life expectancy too. Surely almost everybody alive was under 30.
Actually, that's still true: a majority of people in the world are under 30.
Newton himself lived to be 84. He published Principia Mathematica aged 45. As the article explains, life expectancy is just an average.
But it is relevant here: if most people alive are under 30, most stuff gets done by under 30s.
