Thomas Piketty, the French economist whose best-selling book has added tinder to the debate on income inequality, counts the world's richest person among his fans.

"I had this discussion with Bill Gates a couple of weeks ago," Piketty, the author of "Capital in the Twenty-First Century," said today at an economics conference in Boston. "He told me, `I love everything that's in your book, but I don't want to pay more tax." A tax on wealth is one of Piketty's key recommendations for addressing inequality.

"I understand his point," said Piketty, 43, who teaches at the Paris School of Economics. "I think he sincerely believes he's more efficient than the government, and you know, maybe he is sometimes."

Sure, at cornering a market.