Elon Musk Has A 'Demon Mode,' Says Biographer Who Shadowed The Billionaire For 3 Years

Elon Musk's biographer says the world's richest person lacks empathy and even has what he referred to as a "demon mode."

What To Know: Walter Isaacson has followed Musk closely over the last three years, writing the Tesla Inc TSLA CEO's biography. One of his biggest takeaways during that time is that the eccentric billionaire lacks empathy and has a fierce side that he called "demon mode."

"I'm more impressed with him as an engineer. I think that he does not have a fingertip feel for, you know, empathy, emotions," Isaacson said earlier this year on CNBC's "Squawk Box."

Isaacson's comments don't come as a complete surprise. It's been reported that Musk has a direct communication style and that you don't always know what to expect from the billionaire. 

Related Link: Elon Musk Poses 'Top Risk' To Tesla, Says EV Expert: 'Such An Unpredictable Person'

In an Insider report from the beginning of the year, one of the founding employees of SpaceX Jim Cantrell recalled his time spent working alongside Musk. 

"Working with Elon was like working with two different people: the good Elon and the bad Elon, and you never knew which you were going to get," Cantrell said.

Isaacson told CNBC that a lot of Musk's faults make him who he is. He is a driven individual and it's not just about money for him. He's also impulsive and he will tweet anything that's in his head, he added. 

"When you get up very close to a person, as I have for the past three years with him, you understand that person, you understand the motivations. And there are a lot of faults and he has a demon mode that is destructive," Isaacson said. 

"The question when you write a biography though, is how do you take the dark threads and realize that you can't just pull them out? He wouldn't be who he is without both demon mode and his drive." 

Isaacson's biography on Musk is available for pre-order and is set to be released in later this month. 

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This illustration was generated using artificial intelligence via MidJourney.

Some elements of this story were previously reported by Benzinga and it has been updated.