A true measure of the effect of governmental increase in the amount of money made available, then, is not the simple dollar value of the initial injection but the cumulative effect of this injection through spending and re-spending. In the optimum case the initial expansion of income flow could be great enough to produce tax revenues in excess of the original "deficit spending" or the "tax cut", so that deficits are not only smaller than the increased GNP but are recouped. In Keynesian economics the fundamental point of government policy clearly is not budget-balancing but spending in the event of unused productive capacity and unemployment. Spending increases productivity. This productivity resulting from federal spending has overwhelmed the older economic myths of the balanced budget where government is conceived of as just another business firm.