Professor Stephen Hawking's carer, Claire Dutson, has said that "working with Stephen is never dull" as she escorted him to the UK premiere of a biopic of his life.
Written and narrated by the 71-year-old author of A Brief History Of Time, Professor Hawking tells how he overcame severe disability to become the most famous living scientist in the world.
He attended a reception at Emmanuel College before a showing at the nearby Picturehouse cinema for the opening night of the Cambridge Film Festival.
As she helped him on his arrival, one of his carers, Dutson, said: "I have worked with Stephen for 11 years - it has sometimes been harrowing but mostly fun.
"People see him as a renowned physicist but I just know him as Stephen, who has a great sense of humour."
Stephen Finnigan, the film's director, supported this description of the University of Cambridge professor.
He said: "Stephen was very different to how I imagined him to be.
"You expect him to be quite plain speaking, quite academic and quite brainy but actually you can have a laugh with Stephen Hawking.
"I went for a curry with him this afternoon and you can chat to him about anything."
In the trailer for the film, the University of Cambridge professor says: "This film is a personal journey through my life."
"I have lived five decades longer than doctors predicted. I have tried to make good use of my time."
Hawking has recently spoken out in favour of assisted suicide for people with terminal diseases.
In an interview which will reignite the heated debate surrounding euthanasia, he told the BBC: "We don't let animals suffer, so why humans?"
He said: "I think those who have a terminal illness and are in great pain should have the right to choose to end their lives and those who help them should be free from prosecution.
"But there must be safeguards that the person concerned genuinely wants to end their life and they are not being pressurised into it or have it done without their knowledge or consent, as would have been the case with me."
Prof Hawking was diagnosed with amyotrophic lateral sclerosis, a form of motor neurone disease, when he was 21. He was told he had only a few years to live.
The film goes back to his childhood and his student days and shows him at home with carers.
It features interviews with his family, including his first wife Jane Wilde, along with friends and fellow academics.
Following a bout of pneumonia in 1985, he was placed on a life support machine which his first wife, Jane Hawking, had the option to switch off.
Recovering from the disease, Prof Hawking went on to complete his popular science best-seller A Brief History of Time, which sold more than 10 million copies worldwide.
Only 5% of people with the kind of MND he has - called amyotrophic lateral sclerosis (ALS) or Lou Gehrig's disease - survive for more than a decade after diagnosis.
Referring to euthanasia in 2006, he said: "The victim should have the right to end his life, if he wants. But I think it would be a great mistake. However bad life may seem, there is always something you can do, and succeed at. While there's life, there is hope."