According to Keynes, classical economics held that swings in employment and economic output create profit opportunities that individuals and entrepreneurs have an incentive to pursue, eventually correcting imbalances in the economy. In contrast, Keynes argued that, during recessions, business pessimism and certain characteristics of market economies would exacerbate economic weakness and cause aggregate demand to plunge further. Keynesian economics hold that, during periods of economic woe, governments should undertake deficit spending to make up for the decline in investment and boost consumer spending to stabilize aggregate demand.