group does or accepts an expenses surplus. Global sentence: A general decline of expenses always leads the totality to a decline of revenues and never to a revenue surplus. Related concepts The paradox of thrift has been related to the debt deflation theory of economic crises, being called "the paradox of debt" – people save not to increase savings, but rather to pay down debt. As well, a paradox of toil and a paradox of flexibility have been proposed: A willingness to work more in a liquidity trap and wage flexibility after a debt deflation shock may lead not only to lower wages, but lower employment. During April 2009, U.S. Federal Reserve Vice Chair Janet Yellen discussed the "Paradox of deleveraging" described by economist Hyman Minsky: "Once this massive credit crunch hit, it didn’t take long before we were in a recession. The recession, in turn, deepened the credit crunch as demand and employment fell, and credit losses of financial institutions surged. Indeed, we have been in the grips of precisely this adverse feedback loop for more than a year. A process of balance sheet deleveraging has spread to nearly every corner of the economy. Consumers are pulling back on purchases, especially on durable goods, to build their savings. Businesses are cancelling planned investments and laying off workers to preserve cash. And, financial institutions are shrinking assets to bolster capital and improve their chances of weathering the current storm. Once again, Minsky understood this dynamic. He spoke of the paradox of deleveraging, in which precautions that may be smart for individuals and firms—and indeed essential to return the economy to a normal state—nevertheless magnify the distress of the economy as a whole." Sectoral Balances analysis shows the effect of net savings by the private sector. It must either be funded by a public sector deficit or a by a foreign sector deficit which is equivalent to exports being higher than imports for the country analyzed. Therefore, there exists two types of possible equilibriums for a growing economy. Either the public sector is funding the growth of the private sector via a slight deficit or its current account balance is positive and the country is a net exporter of goods and services. Criticisms Within mainstream economics, non-Keynesian economists, particularly neoclassical economists, criticize this theory on three principal grounds. The first criticism is that, following Say's law and the related circle of