David Rubenstein's new book shares billionaires' investing secrets

David Rubenstein, co-founder of The Carlyle Group and huge philanthropist, is out today with "How To Invest: Masters on the Craft" — interviews with fellow billionaires and pioneers about building wealth.

• A big takeaway, synthesized from advice by Warren Buffett and others: Don't sell so much! Hold on for a long time: You avoid transaction costs, avoid taxes and keep compounding.

Rubenstein, who's donating the book's proceeds to several children's hospitals, told me he set out to "put together a book that would talk about what the insights are from the greatest investors — recognizing that the average person reading it is not going to become one of the greatest investors in the world."

• "Make sure you know what you're doing," he said. "You spend so much time working to earn the money. Spend as much time reading about what you should do with your money."
• He said he hopes to "inspire business students or other undergraduates to want to go into the investing world."

"Investing is not about greed," Rubenstein said. "Most of the investors who really make money are giving away the bulk of it."

• "Secondly, I think that they are doing something useful for society by actually allocating capital to useful things. The venture capitalists who put money into Moderna [maker of a COVID vaccine] did a pretty good thing for society."

Rubenstein's dream for the book? "Well, if I can get my children to read it, that would be Number 1." Don't worry: They're in private equity.

• More on the book.