This week on Moyers & Company (check local listings), the Nobel Laureate economist Joseph E. Stiglitz says the economic situation in America is grave. Inequality is too great, unemployment too high, public investments too meager, corporations too greedy, and the tax code too biased toward the very rich. "We already have a system that isn't working," he tells Bill Moyers. "We already have a tax system that has contributed to making America the most unequal society of the advanced countries... "We can have a tax system that can help create a fairer society. Only ask the people at the top to pay their fair share. It's not asking a lot. It's just saying the top 1% shouldn't be paying a lower tax rate than somebody much further down the scale - [they] shouldn't have the opportunity to move money offshore." Stiglitz believes that taxes can be used as incentives: "If your taxes say we want to encourage real investments in America, then you get real investment in America... But I also believe that you have to shape incentives and that markets on their own don't necessarily shape them the right way." The economist concludes that the barriers to solving our problems are political, not economic, and we can change what's wrong if enough of us insist. Now a professor at Columbia University, Joseph E. Stiglitz served as chairman of the Council of Economic Advisers in the Clinton White House, as chief economist of the World Bank and is currently president of the International Economic Association. He is a best-selling author with a worldwide following that includes presidents and prime ministers. Last week, he published a new call to action, a 27-page report for the Roosevelt Institute on how to reform our tax system and rebuild our country.