In 1982, he was diagnosed with a rare and usually fatal form of cancer:
I asked my first question of my doctor and chemotherapist: "What is the best technical literature about mesothelioma?" She replied, with a touch of diplomacy [...], that the medical literature contained nothing really worth reading. [...]
The literature couldn't have been more brutally clear: mesothelioma is incurable, with a median mortality of only eight months after discovery.
But Gould understood statistics from his work as an evolutionary biologist, and so:
When I learned about the eight-month median, my first intellectual reaction was: fine, half the people will live longer; now what are my chances of being in that half. I read for a furious and nervous hour and concluded, with relief: damned good.
He lived for 20 years, and though he died young, at 60, it was from a different and unrelated form of cancer. An average is indeed an average, and almost no one is the average.