Stephen Hawking fears AI could destroy humankind. Should you worry?

Machines turning on their creators has been a popular theme in books and movies for decades, but very serious people are starting to take the subject very seriously. Physicist Stephen Hawking says, "the development of full artificial intelligence could spell the end of the human race." Tesla Motors and SpaceX founder Elon Musk suggests that AI is probably "our biggest existential threat." Artificial intelligence experts say there are good reasons to pay attention to the fears expressed by big minds like Hawking and Musk -- and to do something about it while there is still time. Hawking made his most recent comments at the beginning of December, in response to a question about an upgrade to the technology he uses to communicate, He relies on the device because he has amyotrophic lateral sclerosis, a degenerative disease that affects his ability to move and speak.