NEW YORK (CNNMoney) -- An Occupy Wall Street group at Harvard University staged a walk-out Wednesday afternoon of the introductory economics class of Greg Mankiw, a former Bush administration economic advisor now working with Republican presidential candidate Mitt Romney.

Mankiw is the main professor in the Economics 10 class that has about 750 students. Jose DelReal, a reporter with The Harvard Crimson, the student newspaper, said about 60 students participated in the walk-out.









Mankiw told CNNMoney Wednesday morning that the class is relatively apolitical, and that guest lecturers have included Larry Summers, who was a top economic advisor for both Presidents Obama and Clinton.

"When I enter a classroom, I try to leave my politics at a door," Mankiw said. "The class is very conventional economics. Adam Smith is pretty non-controversial among economists. But it can seem pretty conservative the first time you hear it."

An open letter to Mankiw posted online by protest leaders explained that the walk-out was being done "to express our discontent with the bias inherent in this introductory economics course."

It objected to the attention given to the teachings of Adam Smith, the father of free market capitalism, at the expense of other economic theorists.

"A legitimate academic study of economics must include a critical discussion of both the benefits and flaws of different economic simplifying models," said the letter. "If Harvard fails to equip its students with a broad and critical understanding of economics, their actions are likely to harm the global financial system. The last five years of economic turmoil have been proof enough of this."

Mankiw said he was initially surprised when he heard of the walk-out plans, but then understood the thinking.

"The economics profession has been implicated, by some people on the left, as a reason for recent developments," he said. "So I shouldn't have been too surprised that we ended up one of the targets."

Mankiw said he was already prepared to have his Wednesday lecture focus on growing inequality in recent decades.

"I'm disappointed the students will miss the lecture," he said. "I think the material is something they'd actually find interesting."

And Mankiw said he is more supportive of the Occupy Wall Street efforts than most of the protestors would realize.

"Over the past 20 years I've noticed a trend towards Harvard students becoming more and more focused on polishing their resumes," he said. "I think focusing more on social and economic policy issues we face is a healthy thing. I may not agree with all Occupy Wall Street movement's positions, but I understand their desire to think about alternative ways to structure society."