British theoretical physicist professor Stephen Hawking speaks to reporters at a news  conference in London on Dec. 2, 2014. (Justin Tallis/AFP/Getty Images)

Famed theoretical physicist Stephen Hawking has lived longer than anyone ever known with the neurodegenerative disease amyotrophic lateral sclerosis, also known as ALS. But Hawking said Wednesday that he would consider assisted suicide under certain circumstances.

Hawking is a known supporter of the controversial practice of assisted suicide, in which the elderly or people with particularly painful or terminal illnesses can take their own lives peacefully, with the assistance of someone like a physician.

[How Stephen Hawking, diagnosed with ALS decades ago, is still alive]

In an interview with Irish comedian Dara O’Briain -- who happens to have his a degree in theoretical physics -- Hawking elaborated on the circumstances under which he would consider taking his own life, with help.

"To keep someone alive against their wishes is the ultimate indignity," Hawking said, according to the Telegraph. "I would consider assisted suicide only if I were in great pain or felt I had nothing more to contribute but was just a burden to those around me.”

[Stephen Hawking says that ‘aggression,’ humanity’s greatest vice, will destroy civilization]

At 21, Hawking was diagnosed with ALS. The disease left him unable to walk or speak. He communicates through a computer program and moves with the assistance of a wheelchair.

Hawking has been close to death before, but improbably, he has survived.

In 2013, Hawking lent his support to efforts to legalize assisted suicide in the United Kingdom, but cautioned that there should be sufficient precautions to protect the vulnerable.

[With its ban on assisted death lifted, will Canada become a ‘suicide tourism’ destination?]

“There must be safeguards that the person concerned genuinely wants to end their life and they are not being pressurized into it or have it done without their knowledge and consent," Hawking noted, according to the Telegraph.

He has lived through that very scenario, the Guardian notes:

In 1985, when suffering complications from pneumonia, his then-wife, Jane, refused to turn off his life-support machine. Hawking recovered and went on to complete his critically and popularly acclaimed book A Brief History of Time.

His work as a physicist continues to this day and Hawking made it clear that he has plenty more to do.

"I am damned if I'm going to die before I have unraveled more of the universe,” he said.

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