Physicist Stephen Hawking has added his voice to the long-running debate over whether assisted suicide for those with terminal illnesses should be legalised. The 71 year-old professor, who is almost entirely paralysed due to motor neurone disease, has given his argument to the BBC: "We don't let animals suffer, so why humans?"

Stephen Hawking
Stephen Hawking Has Publically Stated That He Supports Assisted Suicide.

However, Hawking has warned of the dangers of assisted suicide without proper safeguards where the system could be abused, including the absolute consent of the terminally ill person. "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," he said, referring to the 1985 bout of pneumonia that left him on life support.

Stephen Hawking Chelsea Flower Show
Hawking Would Have Died In 1985 Had His Wife Chosen To Turn His Life Support Off.

His first wife, Jane Wilde, was given the option of turning off the machines keeping her husband alive but she refused, meaning Hawking would eventually recover but would lose his speech completely. Hawking, who has frequently featured in pop culture television shows, such as Star Trek: The Next Generation, The Simpsons, Futurama, and The Big Bang Theory, has narrated a biographical feature-length film that will be released this Friday (20th September).

Watch The Hawking Trailer:

The film, Hawking, is comprised of clips, interviews, and photographs pieced together to narrate the extraordinary story of a man who has not only defied medical science after he was given just two years to live in 1964, he is also one of the greatest scientific minds of our time and has enjoyed an illustrious and ground-breaking career as a cosmoslogist, theoretical physicist and lecturer.

Stephen Hawking Science Fair
Hawking Will Narrate The Documentary Film

Though suicide facilities exist abroad, it is currently a criminal offence in the UK for anyone to encourage or assist another to take their own life regardless of where the death occurs. It is argued by campaigners that assisted suicide aids those who are terminally ill can have no quality of life and they should be permitted to end their life with dignity.

There is opposition by those who believe the instatement of such a system in the UK would be riddled with moral issues and the option could be abused by some.

Hawking will be released on the 20th September in the UK and USA.