An assault on the wealthy isn't a helpful approach to the unequal distribution of income, says former Obama administration economic adviser Larry Summers, now a Harvard professor.

"America succeeds by raising everybody up. It doesn't succeed by tearing anybody down," he told CNBC. "The rhetoric of envy and the rhetoric of tearing down, I don't think, is the right rhetoric for America's leaders."

Summers' comments might have been aimed at progressive politicians who favor higher taxes on the wealthy to fund programs for the poor.

Editor’s Note: 18.79% Annual Returns . . . for Life?

"I think it's important to do something about [income] inequality," Summers said. But it's easier to offer the poor more from a growing pie than a "stagnant pie," he said.

The key economic issue is growth, he explained. If we take care of that, other things will follow.

"If the economy grows fast, the long-term budget will be fine," Summers said. "If the economy does not grow fast, we can do one measure or another, [but] we're still going to have rapid debt accumulation. . . . I hope we move to a focus on more rapid growth."

Meanwhile, a new study from a group of economists indicates that income mobility hasn't changed much in the past 20 years, even though many politicians say it's falling.

Still, the lack of income mobility is a major problem, the economists maintain. "The level of opportunity is alarming, even though it's stable over time," one of the authors, Emmanuel Saez of the University of California, Berkeley, told The New York Times.

Editor’s Note: 18.79% Annual Returns . . . for Life?

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