Nobel prize-winning economist Paul Krugman says that Sen. Jim DeMint (R-SC) is taking "the think out of the think tank" and turning the Heritage Foundation into a "purely political institution" by accepting a job as its president.

The tea party-backed lawmaker announced last week that he would be resigning from the Senate to head the Heritage Foundation because "the conservative movement needs strong leadership in the battle of ideas."

During a Sunday panel discussion on ABC, Republican strategist Mary Matalin sarcastically noted that her "hero," British economist John Maynard Keynes, had said that "ideas drive history, ideas drive progress and Heritage has long been the fount of so many great ideas."

"As a conservative, as a constitutionalist, that was a brilliant move -- a good move for us, a brilliant move for him," she insisted.

"The actual Keynes quote was he said, it's ideas 'which are dangerous for good or evil,'" Krugman pointed out. "I guess I've got a view in this case."

"I'm more interested in what does this do to Heritage?" the liberal economist continued. "I mean, this is somebody who has no sense that he's a researcher or an academic, anything like that. This is sort of taking the think out of the think tank, right? This is turning into a purely political institution."

Watch this video from ABC's This Week, broadcast Dec. 9, 2012.