Leonard Mlodinow in the New York Times:
I always thought that Stephen Hawking would outlive me. I broke into tears when I heard on Wednesday that he had not. He died at his home in Cambridge, England, at 76, after more than half a century of living with amyotrophic lateral sclerosis.
When a man is given three years to live at 21, and he dies 55 years later, it shouldn’t come as a shock. But though I’m 15 years younger then Stephen was, and he had been gravely ill for years, if you knew him you couldn’t help thinking that he would always be around, that his life force was inexhaustible, that he would always have another miracle to pull off.
The scientific community rightly makes much of one of his miracles, a discovery he made in 1974 of something now known as Hawking radiation: the phenomenon in which black holes — so named because nothing can escape them — actually allow radiation to get out.
In popular culture Stephen was another kind of miracle: a floating brain, a disembodied intellect that fit snugly into the stereotype of the genius scientist.
But to me Stephen was also the everyday miracle of an ordinary embodied human — albeit one who had to battle in heroic ways within the confines of his particular shell.