For two years, Walter Isaacson immersed himself in the life of Elon Musk to write the biography of the richest man in the world. Revelations from the book, released September 12, have already made headlines: the psychological scars Musk bears from the way his father treated him as a child; his decision to limit Ukraine’s access to the Starlink satellite network to prevent military operations; his last-minute decision to fire top Twitter executives before their stock options could vest.

Mr. Isaacson struggles with Mr. Musk’s contradictory character traits: He is a remarkably talented and tenacious entrepreneur who has led some of the most innovative companies of our time. But he also lacks empathy for many of the people around him, and his brash behavior has sparked questions about how he handles his extraordinary power.

Mr. Isaacson spoke to The New York Times ahead of the book’s publication. This conversation has been condensed for clarity.

I don’t know. He didn’t ask for a copy and I didn’t send him one.

Yes, but he didn’t give me any strong reactions. He seems remarkably optimistic.

It all started before his Twitter adventure: he became Time magazine’s “Person of the Year,” created an electric car company worth more than all other car companies combined, and put astronauts into orbit . Obviously, he became much more interesting and provocative when he started buying Twitter.

I knew he was unpredictable. I knew he was impulsive. But seeing him up close, especially after he went down the Twitter path, was a much more exciting roller coaster ride for me.

He has an epic vision of himself, almost like he’s a cartoon character wearing his boxers outside, trying to save the world. But I was surprised to see him suddenly realize the difficulty of having so much power, such as controlling where Starlink can be used by Ukraine.

I don’t think he understands it when it comes to X. He is impulsive and sometimes contradictory in the way he handles moderation issues. On the other hand, I think he is fully aware of the power and responsibility that comes from being the only entity that can put American astronauts and military satellites into orbit.

There is no one Elon Musk. He has multiple moods. There are moments where he sees himself in epic, and others where he thinks, “Okay, I need to be more careful. »

We all have demons in our heads since childhood, and he has two orders of magnitude more than most of us. He was able to harness these demons into a driving force. “I need to get humans to Mars, bring us into the era of electric vehicles, and make sure AI is safe. » These are three big missions that I thought were lip service, but which really motivate him. He also has such a need for excitement, drama and risk that whenever things are going well, he cannot settle for them or savor them. It has to put all its chips back on the table, which means it can either go into orbit or collapse.

I expected it and was honestly surprised it never happened. I expected him to say, “You need to leave now. » This only happened at times when SpaceX and classified information were being discussed. He would then say, “Can you leave the room for this? You do not have security clearance. »

One Friday evening, after spending a lot of time with him, I returned to New Orleans. I was at a football game at my old high school and my phone started vibrating. It was the night Musk was dealing with Starlink and Crimea issues with Ukraine. I remember standing behind the stands and being somewhat amazed that this was all happening in real time. He then showed me the encrypted text messages he exchanged with Mykhailo Fedorov, the Ukrainian deputy prime minister.

But I was equally amazed when I attended multiple meetings each week, where participants discussed how, once they colonized Mars, the government would look like, how decisions would be made. would be taken, how and where people would live, who would control the robots. And I was like, “This is crazy. “You know, I’m a normal person and here these people are talking about how to govern communities on Mars.

He thought they had misled him. And like a kid going to summer camp, he learned, “I have to punch people in the nose when they do that. » She’s a person who loves combat, whether it’s playing Elden Ring on her phone or engaging in combative battles on Twitter. Disruptors tend to be really disruptive. And that doesn’t excuse them from doing that kind of thing, but it’s part and parcel of who they are.

I wrote about three people who have had a profound impact on our time. The first is Steve Jobs, who brought us into the digital age with user-friendly computers and a thousand songs in our pockets and phones. The second is Jennifer Doudna, who helped discover the tool called CRISPR, which allows us to modify our own genes. And now, Musk. I think he will have a lasting impact, because, more than anyone, he brought us into the era of electric vehicles, when the big car manufacturers had given up on them, and into space. But in the meantime, I also think it has drawbacks. I think in 10 or 20 years he will be seen as someone important and controversial.