Professor Stephen Hawking has warned that future developments in artificial intelligence may just mean the end of humanity. In other words: sure, you and Siri get on pretty well now, but give her another hundred years and she might be harvesting your grandchildren as fuel cells.

"The primitive forms of artificial intelligence we already have, have proved very useful," the theoretical physicist told the BBC. "But I think the development of full artificial intelligence could spell the end of the human race."

"Once humans develop artificial intelligence it would take off on its own, and re-design itself at an ever increasing rate... Humans, who are limited by slow biological evolution, couldn't compete and would be superseded."

Hawking has amyotrophic lateral sclerosis (ALS) and uses A.I. to speak. He currently employs a new form of software from Intel Labs that predicts his next word based on his previous input. Thanks to the improved version, he needs to type less than 20% of his words. 

The scientist is not the only expert who has sounded caution over our increasing reliance on artificial intelligence. Tesla and SpaceX founder Elon Musk thinks that A.I. poses humanity's "biggest existential threat".

"With artificial intelligence we are summoning the demon," Musk said during a speech at MIT's Centennial Symposium. "In all those stories where there’s the guy with the pentagram and the holy water, it’s like, 'Yeah, he’s sure he can control the demon.' Doesn't work out."

So just how far are we from the robot apocalypse envisioned by films like Terminator and I, Robot? 

Professor Nick Bostrum, an Oxford academic who studies our impending technological future, believes that A.I. is relatively weak right now – but the forthcoming development of super-intelligent A.I. could spell doom for mankind within a century. Time to start stockpiling weapons for the impending war, everyone. 

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