Microsoft co-founder and billionaire Bill Gates is worried about machines becoming super-intelligent one day and doesn't understand why more people aren't right there with him sharing his concerns.

As part of a wide-ranging and fascinating recent Reddit AMA, a fan asked Gates if he thought machine super-intelligence might become a concern going forward. Gates said, at first, machines will do human-helping jobs like picking fruit, but danger could come as they grow smarter and smarter.

"I am in the camp that is concerned about super-intelligence," he said. "First the machines will do a lot of jobs for us and not be super-intelligent. That should be positive if we manage it well. A few decades after that though the intelligence is strong enough to be a concern. I agree with Elon Musk and some others on this and don't understand why some people are not concerned."

Musk, founder of SpaceX and Tesla, said last summer that super-intelligent AI systems are "potentially more dangerous than nukes."

Gates was also asked if he thought full end-to-end encryption of all Internet activity could do anything to protect humanity from the threat of super-intelligent machines. Unfortunately, Gates didn't answer.

If you haven't read Gates' entire Reddit AMA, you should do that. It's a great read.

Are you concerned with machines becoming super-intelligent one day? Let us know in the comments below!