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- Walter Isaacson said on CNBC's Squawk Box that Musk's biggest motivator doesn't appear to be money.
- He shared his view that Musk's love of "contentiousness" is behind his decision-making with Twitter.
- Musk is the world's richest man with a $254 billion fortune, per Bloomberg's Billionaire Index.
For the world's richest person, Elon Musk is not all about the money.
That's according to Walter Isaacson, the biographer who spent three years trailing Musk for a book releasing in September.