Stephen Hawking was a remarkable advocate for people with disabilities

When Stephen Hawking spoke, the world listened. 

The physicist, who died early Wednesday at the age of 76, could never be contained to just one subject. He talked about his life's work — exploring the origin of the universe — while contributing to conversations about topics like fighting for Britain's National Health Service and the importance of bringing science to the masses. 

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And Hawking, who was diagnosed with a nervous system disease known as amyotrophic lateral sclerosis (ALS) in 1963, also became one of the world's most famous advocates for people living with disabilities.

Lucie Bruijn, chief scientist of The ALS Association, an advocacy and research organization in Washington, D.C., described Hawking as an "icon." 

"He was a real figure of hope — that you can do things like communicate and continue to pursue a lifelong dream," she said. 

That Hawking lived more than 50 years beyond his diagnosis was remarkable; the life expectancy of a person with ALS averages two to five years from diagnosis. The disorder progressively robs people of the ability to walk, swallow, speak, and breathe. 

Hawking survived — and thrived — because of his access to high-quality medical care and assistive devices and technologies like a specialized wheelchair and innovative communication systems

His storied life served as inspiration to patients and ALS researchers and clinicians alike, but Bruijn said he worked hard to raise awareness of the disease, met with scientists to discuss medical research, and shared valuable insight about the assistive technologies that helped him communicate after he lost the use of his voice in 1985. 

A few years prior, in 1979, Hawking began working with the Motor Neurone Disease Association, a national charity in the United Kingdom. He was featured in a public awareness campaign for the association last year alongside British actors Benedict Cumberbatch and Eddie Redmayne, both of whom played him on screen. (Motor neurone disease is a term used to describe a group of conditions, including ALS, that affect nerves in the brain and spinal cord.) 

“Prof Hawking did so much to put motor neurone disease on the map," Steve Bell, deputy director of care at the MND Association, said in a statement about Hawking's death. 

When Indrajit Banerjee, director of the knowledge societies division at UNESCO, reached out to Hawking about somehow participating in the organization's 2014 conference on the role of information and communication technology in aiding people with disabilities, he received a moving video in which Hawking spoke about ensuring access to such technology for everyone. Banerjee opened the conference with the clip.

"Without this technology, I would be mute, a prisoner inside my own mind," he said. "I would not be able to ask for a cup of tea, let alone describe my no-boundary theory of how the universe began. Because I have had such phenomenal technological support, I feel a responsibility to speak for others who have not." 

Banerjee said Hawking's "remarkable message" left some in the audience in tears. 

"The way he persisted and continued doing his work — he's an icon by himself," said Banerjee. "But he was also very conscious about his role as someone who could inspire people with disabilities." 

Intel, which worked closely with Hawking to develop his computer-based communication tools, made that software available for free for anyone to use in 2015. Hawking celebrated the software's release of in a video and audio statement, eager to share the technology that transformed his life with countless others.  

The decision to make the software open-source was just one of many gestures that reflected Hawking's decades-long interest in raising awareness and trying to improve life for people with disabilities. 

"I think he had this [mentality]: Given my high profile, I would like to do something for all the people who don’t have the luck to to have access to equipment and access to infrastructure," said Banerjee. 

"It was just pure inspiration to see his determination."

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