Living with motor neurone disease for more than 50 years, Stephen Hawking transcended his disability to becoming one of science's brightest stars, harnessing technology to once again give voice to his ideas.
"My expectations were reduced to zero when I was 21. Everything since then has been a bonus," he told the New York Times in 2004.
Hawking was given only a few years to live when he was diagnosed in 1964, but defied the medical profession in typically stubborn fashion.
"I have lived five decades longer than doctors predicted. I have tried to make good use of my time," he said in 2013 autobiographical documentary "Hawking".
"Because every day could be my last, I have the desire to make the most of each and every minute," he added.
But the disease gradually deprived him of mobility and confined him to a wheelchair.
He was eventually left almost completely paralysed and unable to speak, except through a voice synthesiser operated by facial movements.
Despite his handicap, the scientist was one of the first to popularise deep science, utilising a range of media to educate the general public on the secrets of the universe.
- Household name -
His struggle was portrayed in the 2014 film "The Theory of Everything", which won an Oscar and Golden Globes.
But it was through scientific articles and his 1988 international bestseller "A Brief History of Time" that Hawking was able to communicate his genius and share his discoveries about black holes.
Hawking was an undisputed heavyweight in his field, holding the Lucasian Chair of Mathematics professorship at the University of Cambridge between 1978 and 2009, a post once held by Isaac Newton, the father of universal gravity.
"My disabilities have not been a significant handicap in my field, which is theoretical physics," he said in Science Digest in 1984.
"Indeed, they have helped me in a way by shielding me from lecturing and administrative work that I would otherwise have been involved in."
In recent years, he enthusiastically adopted social media to spread his scientific research, responding to fans with messages signed off "SH".
He boasted 4.1 million Facebook followers, nearly 30,000 on Twitter and amassed millions of followers within hours when he signed up to Chinese social media platform Weibo.
- 'Keep talking' -
Hawking credited the support of his family and friends with giving him the strength to keep up his remarkable pace.
"I have managed, however, only because of the large amount of help I have received from my wife, children, colleagues and students," he said.
As news broke of his death, Hawking's philosophical musings became particularly poignant.
"For millions of years, mankind lived just like the animals," he once said.
"Then something happened which unleashed the power of our imagination.
"We learned to talk and we learned to listen. Mankind's greatest achievements have come about by talking, and its greatest failures by not talking.
"With the technology at our disposal, the possibilities are unbounded. All we need to do is make sure we keep talking."