As a former denizen of Harvard, I've had to learn that a sense of reality doesn't always flourish in elite institutions. It is the street virtue par excellence. Bus drivers can display a shrewder grasp of what's what than Nobel Prize winners. The only way any of us can improve our grasp of reality is to confront the world every day and learn, mostly from our mistakes, what works and what doesn't. Yet even lengthy experience can fail us in life and in politics. Experience can imprison decision-makers in worn-out solutions while blinding them to the untried remedy that does the trick.