At age 17, Elon Musk left his home in South Africa and moved to Canada, where he enrolled at Queen's University in Kingston, Ontario. During his freshman-year in the fall of 1990, Musk befriended Navaid Farooq while living in the same dorm, according to the book "Elon Musk: Tesla, SpaceX, and the Quest for a Fantastic Future," by Ashlee Vance.

Farooq, a Canadian who grew up in Geneva, bonded with Musk over their backgrounds abroad and their interest in strategy games, according to the book. Living in such close quarters, Farooq learned a lot about Musk, including what Farooq sees as his defining trait.

"When Elon gets into something, he develops just this different level of interest in it than other people," Farooq said in Vance's book. "This is what differentiates Elon from the rest of humanity."

For example, Farooq recalled that when strategy video game Civilization was released in 1991, the two spent hours playing together.

"Elon could lose himself for hours on end," Farooq said. (Research has linked the ability to filter out distracting information to high intelligence.)

Farooq related: "We were the kinds of people that can be by ourselves at a party and not feel awkward. We can think to ourselves and not feel socially awkward about it."

According to the book, Musk's intensity was a "constant" during the pair's long friendship, even beyond video games.

In college, Musk took his education more seriously — he studied business, competed in public speaking contests and went head-to-head with his classmates when it came to test scores, according to the book.

After an economics exam, Musk, Farooq and their other classmates compared notes to try to estimate their exam scores, when it became clear that Musk had a much better handle on the material than the rest.

"This was a group of fairly high achievers, and Elon stood way outside the bell curve," Farooq said.

Others close to Musk noticed the tendencies in him as Farooq did.

"He would call very insistently," Justine Musk, Elon's first wife, told author Vance about dating Musk in college. "You always knew it was Elon because the phone would never stop ringing. The man does not take no for an answer. You can't blow him off. I do think of him as the Terminator. He locks his gaze on to something and says, 'it shall be mine.'"

Justine also said Musk would compare his grades with hers. She and Musk took the same abnormal psychology class, and after an exam, Justine received a 97, Musk a 98.

"He went back to the professor, and talked his way into the two points he lost and got a hundred," Justine said in the book. "It felt like we were always competing."

Musk still seems to have that intensity and the ability to lose himself in whatever project is at hand. He told Kara Swisher in November 2018 that he was working 120 hours a week in an effort to ramp up Tesla Model 3 production.

"There were times when, some weeks ... I haven't counted exactly, but I would just sort of sleep for a few hours, work, sleep for a few hours, work, seven days a week. Some of those days must have been 120 hours or something nutty," Musk said.

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