Former Microsoft (NASDAQ:MSFT) CEO Bill Gates has voiced his concerns over advanced AI.

Bill Gates talked about AI during a Reddit AskMeAnything Q&A discussion. One user asked him how he felt about the subject and he said we should be more concerned about it than what people are, reports Tech Radar.

Bill Gates didn’t say that AI was an immediate concern. However, he did say that in the next few decades people should start focusing on it more. Stephen Hawking and Tesla Motors (NASDAQ:TSLA) CEO Elon Musk have also expressed their concerns over AI, Tech Radar notes.

“AI doomsday scenarios belong more in the realm of science fiction than science fact,” Eric Horvitz, director of research for Microsoft, told VentureBeat.

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