Stephen Hawking was no ordinary person. But was he ‘extraordinary’?

At age 21 he was given two years to live, but he died aged 76. People thought that the ALS that afflicted him, eating away at his nerves and withering his body, would end him, and yet he survived: more than that, for decades he contributed his brilliant thinking to the world of science. He was confined to a wheelchair, using machines and computers so the contents of his head