Why Zuckerberg and Musk Are Fighting About the Robot Future

Elon Musk and Mark Zuckerberg are having a spat about whether or not artificial intelligence is going to kill us all.

Musk, the chief of Tesla and SpaceX who has longstanding worries about the potentially apocalyptic future of AI, recently returned to that soapbox, making an appeal for proactive regulations on AI. “I keep sounding the alarm bell,” he told attendees at a National Governors Association meeting this month. “But until people see robots going down the street killing people, they don’t know how to react.”

In a , Zuckerberg, Facebook’s CEO, offered riposte. He called Musk a “naysayer” and accused his doomsday fears of unnecessary negativity. “In some ways I actually think: “I’ve talked to Mark about this. His understanding of the subject is limited.”