Instead of these four categories, "AI will increasingly replace repetitive jobs. Not just for blue-collar work but a lot of white-collar work," Lee explains, predicting that 40 percent of jobs in the world will become "displaceable" by technology. "Basically chauffeurs, truck drivers anyone who does driving for a living their jobs will be disrupted more in the 15- to 20-year time frame and many jobs that seem a little bit complex, chef, waiter, a lot of things will become automated, we'll have automated stores, automated restaurants." The difference between the robot revolution and other revolutions that have disrupted the labor markets is the rate of change, says Lee. "The invention of the steam engine, the sewing machine, electricity, have all displaced jobs. And we've gotten over it. The challenge of AI is this 40 percent, whether it is 15 or 25 years, is coming faster than the previous revolutions," he said on "60 Minutes."

Billionaire Elon Musk has said cash handouts'will be necessary' if robots take human jobs, in his latest flurry of tweets. Musk made the comment in response to a question from a Twitter user about whether he supported universal basic income (UBI) - a cash handout that could be given to people irrespective of their employment. Musk believes UBI could be a possible solution for unemployment caused by machines taking over the workforce. Billionaire Elon Musk has said cash handouts'will be necessary' if robots take human jobs, in his latest flurry of tweets A universal basic income would give a standard amount of money to every citizen to cover basic expenses like food and living costs each month. Musk first joined the growing list of tech executives supporting the payment system in 2016 when he spoke about the concept in an interview.

So new jobs will have to be created, says Branson. But also, a "basic minimum earnings," or a universal basic income, should be instituted "so that there is nobody that is having to sleep on the street," Branson tells CNN. "One hundred percent, I think that is really important." Universal basic income is a cash handout, distributed irrespective of employment status. CNN's Romans says a common opposition to a cash handouts is that it would create a "nanny state," where individuals are disincentivized to work.