Keynesianism

Keynesian economics (/ˈkeɪnziən/ KAYN-zee-ən; or Keynesianism) are the various theories about how in the short run, and especially during recessions, economic output is strongly influenced by aggregate demand (total spending in the economy). In the Keynesian view, aggregate demand does not necessarily equal the productive capacity of the economy; instead, it is influenced by a host of factors and sometimes behaves erratically, affecting production, employment, and inflation.

The theories forming the basis of Keynesian economics were first presented by the British economist John Maynard Keynes during the Great Depression in his 1936 book, The General Theory of Employment, Interest and Money. Keynes contrasted his approach to the aggregate supply-focused classical economics that preceded his book. The interpretations of Keynes that followed are contentious and several schools of economic thought claim his legacy.

Keynesian economists generally argue that, as aggregate demand is volatile and unstable, a market economy will often experience inefficient macroeconomic outcomes. These can be mitigated by active policy responses, in particular, monetary policy actions by the central bank and fiscal policy actions by the government, can help stabilize output over the business cycle. Keynesian economists often advocate an active role for government intervention during recessions.

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