One of history’s most inspiring and fascinating humans has breathed his last. Stephen Hawking is dead.

Hawking defied barriers.

A brilliant physicist, he used humor and plain language to make the wonders of the universe more understandable and relevant to the average Joe and Jane.

Hawking’s communication skills overcame a debilitating physical condition which left him confined to a wheelchair and, by 1985, unable to speak. So he developed a computerized voice synthesizer. It became a defining feature of his public persona.

That the University of Cambridge professor lived so long, dying at 76, defied all odds. Diagnosed at 21 with amyotrophic lateral sclerosis, experience suggested he would die in a few years. There is no record of anyone living so long with ALS. Some might call it a miracle, but Hawking, who looked to the laws of physics to explain humanity’s reason for being, would certainly demand a scientific explanation.

“As recent advances in cosmology suggest, the laws of gravity and quantum theory allow universes to appear spontaneously from nothing. Spontaneous creation is the reason there is something rather than nothing, why the universe exists, why we exist. It is not necessary to invoke God to light the blue touch paper and set the universe going. Our universe seems to be one of many, each with different laws,” Hawking wrote in 2010’s “Grand Design,” co-authored by fellow physicist Leonard Mlodinow.

He leaves to physicists the challenge of exploring his many theories, including “Hawking radiation,” an attempt to explain some inexplicable contradictions between the laws of physics and the growing knowledge of black holes.

To humanity, Hawking leaves his explanations of how physics demonstrates the interconnectedness of all things, most eloquently described in his 1988 bestseller, “A Brief History of Time.”

“Space and time not only affect but also are affected by everything that happens in the universe,” he wrote.

Far out, Stephen.

And he leaves us with warnings about humanity’s failure to consider the consequences of our actions.

Hawking feared humans were on a fast track to extinction because of rapid climate change, population growth, the presence of nuclear and biological weapons and threat of uncontrolled epidemics. Colonizing other planets might be the only assurance of survival, he concluded.

And, said Hawking, people should move cautiously in developing artificial intelligence, potentially opening a door to self-aware robots that could supplant, or eliminate, their inferior biological creators.

Stephen Hawking made you think.

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