Sourced from The Economist:
In neither contribution did Mr Krugman claim great originality for his ideas or great realism. His achievement was to formalise insights that many people had previously had informally. Ideas that had fluttered in and out of people’s grasp for decades, he pinned down like a butterfly on display. Sometimes a good economist, like a good columnist, succeeds not by making a point before everyone else, but by making it better than anyone else.