Keynesian Economics

framework · economics · organizing-schema

Macroeconomic framework emphasizing aggregate demand and active fiscal management.

Keynesian economics is the macroeconomic framework descended from John Maynard Keynes's General Theory (1936), which argued that aggregate demand can fall persistently short of full-employment output and that active fiscal and monetary policy is sometimes required to restore it. The framework introduced the consumption function, the multiplier, liquidity preference theory of interest rates, and the paradox of thrift, and provided the analytical scaffolding for postwar demand management policy. Subsequent developments — neo-Keynesian synthesis (Hicks-Samuelson IS-LM), Post-Keynesian (Robinson, Minsky), and New Keynesian (Mankiw, Romer, Woodford with microfoundations and rational expectations) — represent very different theoretical commitments while sharing the central concern with demand-side determinants of output.

Originators

John Maynard Keynes; subsequent developments by John Hicks, Paul Samuelson, Hyman Minsky, Joan Robinson, and the New Keynesian school high

Year / Decade

1936 (General Theory); ongoing developments through twentieth and twenty-first centuries high

Primary sources

Keynes, J.M. (1936). The General Theory of Employment, Interest and Money, Hicks, J.R. (1937). 'Mr. Keynes and the Classics: A Suggested Interpretation', Econometrica high

Core components

Aggregate demand and effective demand
Consumption function and multiplier
Liquidity preference
Sticky prices and wages (especially in New Keynesian formulations)
Paradox of thrift
Fiscal stimulus
Animal spirits
IS-LM (Hicks synthesis)

Primary use case

Macroeconomic policy framework, particularly during demand-deficient downturns; basis for fiscal stimulus during the 2008 and 2020 crises; ongoing influence in central banking and Treasury practice.

Common criticisms

Lucas critique (1976) on the instability of estimated relationships under policy regime change
failure to account for stagflation in the 1970s prompted New Classical revival
debates over fiscal multiplier size and crowding-out remain unsettled empirically
assumes governments can identify and act on output gaps in real time
political-economy concerns about asymmetric application (stimulus in downturns without surplus in upturns).

Lineage

Siblings: Monetarism, Austrian School, Phillips Curve