Ben Bernanke: I spent my entire academic career studying the Great Depression. The depression may have started because of a stock market crash, but what hit the general economy was a disruption of credit. Average citizens unable to borrow money, to do anything. To buy a home, start a business, stock their shelves. Credit has the ability to build a modern economy, but lack of credit has the ability to destroy it, swiftly and absolutely. If we do not act, boldly and immediately, we will replay the depression of the 1930s, only this time it will be far, far worse. We don't do this now, we won't have an economy on Monday.