Keynesian economics (pronounced /ˈkeɪnziən/ KAYN-zee-ən, also called Keynesianism and Keynesian theory) is a
macroeconomic theory based on the ideas of 20th century British economist John Maynard Keynes. Keynesian
economics argues that private sector decisions sometimes lead to inefficient macroeconomic outcomes and therefore
advocates active policy responses by the public sector, including monetary policy actions by the central bank and
fiscal policy actions by the government to stabilize output over the business cycle.[1] The theories forming the basis
of Keynesian economics were first presented in The General Theory of Employment, Interest and Money, published
in 1936; the interpretations of Keynes are contentious, and several schools of thought claim his legacy.
Keynesian economics advocates a mixed economy—predominantly private sector, but with a large role of
government and public sector—and served as the economic model during the latter part of the Great Depression,
World War II, and the post-war economic expansion (1945–1973), though it lost some influence following the
stagflation of the 1970s. The advent of the global financial crisis in 2007 has caused a resurgence in Keynesian
thought. The former British Prime Minister Gordon Brown, former President of the United States George W. Bush[2]
( also alleged heavily being anti-Keynesian by some (The Shock Doctrine)), President of the United States Barack
Obama, and other world leaders have used Keynesian economics through government stimulus programs to attempt
to assist the economic state of their countries.[3]
Overview
According to Keynesian theory, some microeconomic-level actions—if taken collectively by a large proportion of
individuals and firms—can lead to inefficient aggregate macroeconomic outcomes, where the economy operates
below its potential output and growth rate. Such a situation had previously been referred to by classical economists
as a general glut. There was disagreement among classical economists (some of whom believed in Say's Law—that
"supply creates its own demand"), on whether a general glut was possible. Keynes contended that a general glut
would occur when aggregate demand for goods was insufficient, leading to an economic downturn with
unnecessarily high unemployment and losses of potential output. In such a situation, government policies could be
used to increase aggregate demand, thus increasing economic activity and reducing unemployment and deflation.
Most Keynesians advocate an activist stabilization policy to reduce the amplitude of the business cycle, which they
rank among the most serious of economic problems. Now, this does not necessarily mean fine-tuning, but it does
mean what might be called 'coarse-tuning.' For example, when the unemployment rate is very high, a government
can use a dose of expansionary monetary policy.
Keynes argued that the solution to the Great Depression was to stimulate the economy ("inducement to invest")
through some combination of two approaches: a reduction in interest rates and government investment in
infrastructure. Investment by government injects income, which results in more spending in the general economy,
which in turn stimulates more production and investment involving still more income and spending and so forth. The
initial stimulation starts a cascade of events, whose total increase in economic activity is a multiple of the original
investment.[4]
A central conclusion of Keynesian economics is that, in some situations, no strong automatic mechanism moves
output and employment towards full employment levels. This conclusion conflicts with economic approaches that
assume a strong general tendency towards equilibrium. In the 'neoclassical synthesis', which combines Keynesian
macro concepts with a micro foundation, the conditions of general equilibrium allow for price adjustment to
eventually achieve this goal. More broadly, Keynes saw his theory as a general theory, in which utilization of
resources could be high or low, whereas previous economics focused on the particular case of full utilization.
The new classical macroeconomics movement, which began in the late 1960s and early 1970s, criticized Keynesian
theories, while New Keynesian economics has sought to base Keynes' ideas on more rigorous theoretical
Source URL:http://www.en.wikipedia.org/wiki/Keynesian_economics
Saylor URL: http://www.saylor.org/courses/econ305
Attributed to [Wikipedia] Saylor.org
Page 1 of 12
, foundations.
Some interpretations of Keynes have emphasized his stress on the international coordination of Keynesian policies,
the need for international economic institutions, and the ways in which economic forces could lead to war or could
promote peace.[5]
Precursors
Keynes's work was part of a long-running debate within economics over the existence and nature of general gluts.
While a number of the policies Keynes advocated (notably government deficit spending) and the theoretical ideas he
proposed (effective demand, the multiplier, the paradox of thrift) were advanced by various authors in the 19th and
early 20th century, Keynes's unique contribution was to provide a general theory of these, which proved acceptable
to the political and economic establishments.
Schools
An intellectual precursor of Keynesian economics was underconsumption theory in classical economics, dating from
such 19th century economists as Thomas Malthus, the Birmingham School of Thomas Attwood,[6] and the American
economists William Trufant Foster and Waddill Catchings, who were influential in the 1920s and 1930s.
Underconsumptionists were, like Keynes after them, concerned with failure of aggregate demand to attain potential
output, calling this "underconsumption" (focusing on the demand side), rather than "overproduction" (which would
focus on the supply side), and advocating economic interventionism. Keynes specifically discussed
underconsumption (which he wrote "under-consumption") in the General Theory, in Chapter 22, Section IV [7] and
Chapter 23, Section VII [8].
Numerous concepts were developed earlier and independently of Keynes by the Stockholm school during the 1930s;
these accomplishments were described in a 1937 article, published in response to the 1936 General Theory, sharing
the Swedish discoveries.[9]
Concepts
The multiplier dates to work in the 1890s by the Australian economist Alfred De Lissa, the Danish economist Julius
Wulff, and the German American economist Nicholas Johannsen,[10] the latter being cited in a footnote of
Keynes.[11] Nicholas Johannsen also proposed a theory of effective demand in the 1890s.
The paradox of thrift was stated in 1892 by John M. Robertson in his The Fallacy of Savings, in earlier forms by
mercantilist economists since the 16th century, and similar sentiments date to antiquity:[12] [13]
Today these ideas, regardless of provenance, are referred to in academia under the rubric of "Keynesian economics",
due to Keynes's role in consolidating, elaborating, and popularizing them.
Keynes and the Classics
Keynes sought to distinguish his theories from and oppose them to "classical economics," by which he meant the
economic theories of David Ricardo and his followers, including John Stuart Mill, Alfred Marshall, Francis Ysidro
Edgeworth, and Arthur Cecil Pigou. A central tenet of the classical view, known as Say's law, states that "supply
creates its own demand". Say's Law can be interpreted in two ways. First, the claim that the total value of output is
equal to the sum of income earned in production is a result of a national income accounting identity, and is therefore
indisputable. A second and stronger claim, however, that the "costs of output are always covered in the aggregate by
the sale-proceeds resulting from demand" depends on how consumption and saving are linked to production and
investment. In particular, Keynes argued that the second, strong form of Say's Law only holds if increases in
individual savings exactly match an increase in aggregate investment.[14]
Source URL:http://www.en.wikipedia.org/wiki/Keynesian_economics
Saylor URL: http://www.saylor.org/courses/econ305
Attributed to [Wikipedia] Saylor.org
Page 2 of 12
macroeconomic theory based on the ideas of 20th century British economist John Maynard Keynes. Keynesian
economics argues that private sector decisions sometimes lead to inefficient macroeconomic outcomes and therefore
advocates active policy responses by the public sector, including monetary policy actions by the central bank and
fiscal policy actions by the government to stabilize output over the business cycle.[1] The theories forming the basis
of Keynesian economics were first presented in The General Theory of Employment, Interest and Money, published
in 1936; the interpretations of Keynes are contentious, and several schools of thought claim his legacy.
Keynesian economics advocates a mixed economy—predominantly private sector, but with a large role of
government and public sector—and served as the economic model during the latter part of the Great Depression,
World War II, and the post-war economic expansion (1945–1973), though it lost some influence following the
stagflation of the 1970s. The advent of the global financial crisis in 2007 has caused a resurgence in Keynesian
thought. The former British Prime Minister Gordon Brown, former President of the United States George W. Bush[2]
( also alleged heavily being anti-Keynesian by some (The Shock Doctrine)), President of the United States Barack
Obama, and other world leaders have used Keynesian economics through government stimulus programs to attempt
to assist the economic state of their countries.[3]
Overview
According to Keynesian theory, some microeconomic-level actions—if taken collectively by a large proportion of
individuals and firms—can lead to inefficient aggregate macroeconomic outcomes, where the economy operates
below its potential output and growth rate. Such a situation had previously been referred to by classical economists
as a general glut. There was disagreement among classical economists (some of whom believed in Say's Law—that
"supply creates its own demand"), on whether a general glut was possible. Keynes contended that a general glut
would occur when aggregate demand for goods was insufficient, leading to an economic downturn with
unnecessarily high unemployment and losses of potential output. In such a situation, government policies could be
used to increase aggregate demand, thus increasing economic activity and reducing unemployment and deflation.
Most Keynesians advocate an activist stabilization policy to reduce the amplitude of the business cycle, which they
rank among the most serious of economic problems. Now, this does not necessarily mean fine-tuning, but it does
mean what might be called 'coarse-tuning.' For example, when the unemployment rate is very high, a government
can use a dose of expansionary monetary policy.
Keynes argued that the solution to the Great Depression was to stimulate the economy ("inducement to invest")
through some combination of two approaches: a reduction in interest rates and government investment in
infrastructure. Investment by government injects income, which results in more spending in the general economy,
which in turn stimulates more production and investment involving still more income and spending and so forth. The
initial stimulation starts a cascade of events, whose total increase in economic activity is a multiple of the original
investment.[4]
A central conclusion of Keynesian economics is that, in some situations, no strong automatic mechanism moves
output and employment towards full employment levels. This conclusion conflicts with economic approaches that
assume a strong general tendency towards equilibrium. In the 'neoclassical synthesis', which combines Keynesian
macro concepts with a micro foundation, the conditions of general equilibrium allow for price adjustment to
eventually achieve this goal. More broadly, Keynes saw his theory as a general theory, in which utilization of
resources could be high or low, whereas previous economics focused on the particular case of full utilization.
The new classical macroeconomics movement, which began in the late 1960s and early 1970s, criticized Keynesian
theories, while New Keynesian economics has sought to base Keynes' ideas on more rigorous theoretical
Source URL:http://www.en.wikipedia.org/wiki/Keynesian_economics
Saylor URL: http://www.saylor.org/courses/econ305
Attributed to [Wikipedia] Saylor.org
Page 1 of 12
, foundations.
Some interpretations of Keynes have emphasized his stress on the international coordination of Keynesian policies,
the need for international economic institutions, and the ways in which economic forces could lead to war or could
promote peace.[5]
Precursors
Keynes's work was part of a long-running debate within economics over the existence and nature of general gluts.
While a number of the policies Keynes advocated (notably government deficit spending) and the theoretical ideas he
proposed (effective demand, the multiplier, the paradox of thrift) were advanced by various authors in the 19th and
early 20th century, Keynes's unique contribution was to provide a general theory of these, which proved acceptable
to the political and economic establishments.
Schools
An intellectual precursor of Keynesian economics was underconsumption theory in classical economics, dating from
such 19th century economists as Thomas Malthus, the Birmingham School of Thomas Attwood,[6] and the American
economists William Trufant Foster and Waddill Catchings, who were influential in the 1920s and 1930s.
Underconsumptionists were, like Keynes after them, concerned with failure of aggregate demand to attain potential
output, calling this "underconsumption" (focusing on the demand side), rather than "overproduction" (which would
focus on the supply side), and advocating economic interventionism. Keynes specifically discussed
underconsumption (which he wrote "under-consumption") in the General Theory, in Chapter 22, Section IV [7] and
Chapter 23, Section VII [8].
Numerous concepts were developed earlier and independently of Keynes by the Stockholm school during the 1930s;
these accomplishments were described in a 1937 article, published in response to the 1936 General Theory, sharing
the Swedish discoveries.[9]
Concepts
The multiplier dates to work in the 1890s by the Australian economist Alfred De Lissa, the Danish economist Julius
Wulff, and the German American economist Nicholas Johannsen,[10] the latter being cited in a footnote of
Keynes.[11] Nicholas Johannsen also proposed a theory of effective demand in the 1890s.
The paradox of thrift was stated in 1892 by John M. Robertson in his The Fallacy of Savings, in earlier forms by
mercantilist economists since the 16th century, and similar sentiments date to antiquity:[12] [13]
Today these ideas, regardless of provenance, are referred to in academia under the rubric of "Keynesian economics",
due to Keynes's role in consolidating, elaborating, and popularizing them.
Keynes and the Classics
Keynes sought to distinguish his theories from and oppose them to "classical economics," by which he meant the
economic theories of David Ricardo and his followers, including John Stuart Mill, Alfred Marshall, Francis Ysidro
Edgeworth, and Arthur Cecil Pigou. A central tenet of the classical view, known as Say's law, states that "supply
creates its own demand". Say's Law can be interpreted in two ways. First, the claim that the total value of output is
equal to the sum of income earned in production is a result of a national income accounting identity, and is therefore
indisputable. A second and stronger claim, however, that the "costs of output are always covered in the aggregate by
the sale-proceeds resulting from demand" depends on how consumption and saving are linked to production and
investment. In particular, Keynes argued that the second, strong form of Say's Law only holds if increases in
individual savings exactly match an increase in aggregate investment.[14]
Source URL:http://www.en.wikipedia.org/wiki/Keynesian_economics
Saylor URL: http://www.saylor.org/courses/econ305
Attributed to [Wikipedia] Saylor.org
Page 2 of 12
