Summers says that today the problem of too much saving has reappeared. The centerpiece of his argument is “the natural interest rate,” defined as the interest rate at which full employment is established by the equality of saving with investment. If people save more than investors invest, the saved money will not find its way back into the economy, and output and employment will fall.
Summers notes that despite a zero real rate of interest, there is still substantial unemployment. In other words, not even a zero rate of interest can reduce saving to the level of investment, thus frustrating a full employment recovery. Summers concludes that the natural rate of interest has become negative and is stuck below zero.
How to fix this? The way to fix it, Summers says, is to charge people for saving money. To avoid the charges, people would spend the money, thus reducing savings to the level of investment and restoring full employment.
Summers acknowledges that the problem with his solution is that people would take their money out of banks and hoard it in cash holdings. In other words, the cash form of money provides consumers with a freedom to save that holds down consumption and prevents full employment.
Summers has a fix for this: eliminate the freedom by imposing a cashless society where the only money is electronic. As electronic money cannot be hoarded except in bank deposits, penalties can be imposed that force unproductive savings into consumption.