Stephen Hawking, who has died aged 76, was Britain's most famous modern day scientist, a genius who dedicated his life to unlocking the secrets of the Universe.
Born on January 8, 1942 - 300 years to the day after the death of the father of modern science, Galileo Galilei - he believed science was his destiny.
But fate also dealt Hawking a cruel hand.
Most of his life was spent in a wheelchair crippled by amyotrophic lateral sclerosis (ALS), a form of motor neurone disease that attacks the nerves controlling voluntary movement.
Remarkably, Hawking defied predictions he would only live for a few years, overcoming its debilitating effects on his mobility and speech that left him paralysed and able to communicate only via a computer speech synthesiser.
"I am quite often asked: how do you feel about having ALS?" he once wrote. "The answer is, not a lot.
"I try to lead as normal a life as possible, and not think about my condition, or regret the things it prevents me from doing, which are not that many."
"My goal is simple," he once said. "It is complete understanding of the universe, why it is as it is and why it exists at all."
"I believe life on Earth is at an ever-increasing risk of being wiped out by a disaster such as sudden global warming, nuclear war, a genetically engineered virus or other dangers."
Hawking also warned Britain ahead of the Brexit referendum in 2016 against leaving the European Union: "Gone are the days when we could stand on our own against the world."