Teoria keynesiana

What Is Teoria keynesiana?

Teoria keynesiana, or Keynesian economics, is a macroeconomic theory that posits that government intervention can stabilize an economy, particularly during economic downturns. It is a fundamental school of thought within the broader field of macroeconomia. Developed by British economist John Maynard Keynes, the theory argues that aggregate demand—the total spending in an economy—is the primary driver of economic activity and that inadequate demand can lead to prolonged periods of high unemployment and economic recession. Unlike earlier classical economic views, Teoria keynesiana suggests that economies do not automatically self-correct to full employment in the short run and may require active stabilization policies, such as fiscal policy and monetary policy, to mitigate the adverse effects of business cycles.

History and Origin

Teoria keynesiana emerged from the intellectual ferment of the Great Depression, a period marked by unprecedented unemployment and economic stagnation that defied conventional economic explanations. John Maynard Keynes's seminal work, The General Theory of Employment, Interest and Money, published in February 1936, laid the foundation for this new economic paradigm. Key⁴nes challenged the prevailing classical belief that markets would naturally lead to full employment, arguing instead that a lack of effective demand could result in an equilibrium with high unemployment. His work provided a theoretical justification for government intervention to manage the economy, shifting the focus of economic policy from laissez-faire to active demand management. The ideas presented in The General Theory catalyzed a profound shift in economic thought, giving macroeconomics a central place in economic theory and contributing much of its terminology.

Key Takeaways

• Teoria keynesiana emphasizes that aggregate demand is the primary force determining economic output and employment.
• The theory posits that market economies can experience prolonged periods of high unemployment and underutilized capacity if aggregate demand is insufficient.
• Keynesian economics advocates for active government intervention through fiscal and monetary policies to stabilize the economy and counteract economic downturns.
• Keynesian analysis suggests that sticky wages and prices prevent rapid market self-correction, necessitating policy action.
• A core tenet is the belief that government spending can stimulate demand and employment, particularly during a recession.

Formula and Calculation

While Teoria keynesiana is a broad theoretical framework rather than a single formula, a central concept is the composition of aggregate demand (AD), which can be expressed as:

$AD = C + I + G + (X - M)$

Where:

• (AD) represents Aggregate demand, the total spending on goods and services in an economy.
• (C) represents Consumption, total spending by households.
• (I) represents Investment, total spending by businesses on capital goods.
• (G) represents Government Spending, total spending by the government.
• (X) represents Exports, goods and services sold to other countries.
• (M) represents Imports, goods and services purchased from other countries.

The Keynesian model also highlights the multiplier effect, which illustrates how an initial change in spending (e.g., government spending or investment) can lead to a larger change in overall economic output.

Interpreting the Teoria keynesiana

Interpreting Teoria keynesiana involves understanding that economic downturns, such as recessions or depressions, are primarily caused by insufficient aggregate demand. When businesses face low demand, they reduce production and lay off workers, leading to higher unemployment and further declines in consumption. Keynesian thought suggests that self-correcting mechanisms, often relied upon by classical economists, are too slow or ineffective to restore full employment quickly. Therefore, policymakers should actively intervene to boost demand. This often means increasing government spending or cutting taxes (fiscal policy), or lowering interest rates and increasing the money supply (monetary policy). The goal is to stimulate economic activity, create jobs, and bring the economy back to its potential output.

Hypothetical Example

Consider a hypothetical country, "Econland," experiencing a severe economic recession with high unemployment and factories operating far below capacity. According to Teoria keynesiana, this situation stems from a significant fall in private sector aggregate demand. Businesses are not investing, and consumers are not spending.

To combat this, Econland's government, advised by Keynesian economists, decides to implement a large-scale infrastructure project, such as building new high-speed rail lines. This involves a substantial increase in government spending. The government contracts construction companies, which then hire unemployed workers, purchase raw materials, and invest in new machinery. These workers, now earning incomes, begin to spend more on goods and services, leading to increased demand for other businesses. These businesses, in turn, may hire more staff or increase their own investments. This ripple effect, known as the multiplier effect, demonstrates how the initial government spending injection leads to a much larger increase in overall economic activity and a rise in Econland's Gross Domestic Product.

Practical Applications

Teoria keynesiana has profoundly influenced global economic policy, particularly in response to crises. Governments worldwide have adopted Keynesian principles, especially during significant economic downturns. For instance, the fiscal stimulus packages implemented by various countries following the 2008 global financial crisis were largely rooted in Keynesian ideas of boosting aggregate demand when private spending falters. Cen³tral banks, influenced by Keynesian thought, often engage in expansionary monetary policy, such as lowering interest rates or implementing quantitative easing, to encourage borrowing, investment, and consumption during recessions. Historically, the passage of the Employment Act of 1946 in the United States also reflected a Keynesian commitment to using government policy to promote maximum employment and economic stability.

##² Limitations and Criticisms

Despite its widespread influence, Teoria keynesiana has faced several limitations and criticisms. One common critique revolves around the potential for inflation and government debt. Critics argue that persistent increases in government spending and loose monetary policies can lead to excessive inflation or unsustainable levels of national debt, potentially crowding out private investment.

An¹other significant challenge arose in the 1970s with the phenomenon of "stagflation" – high inflation coupled with high unemployment – which Keynesian models at the time struggled to explain effectively. This period led to the rise of alternative economic schools of thought, such as monetarism, which emphasized the role of the money supply. Milton Friedman, a prominent critic of Keynesian economics, argued that attempts by central banks to manipulate interest rates were often misguided and could lead to unintended consequences for the broader economy. Furthermore, the concept of the liquidity trap, where monetary policy becomes ineffective because interest rates are already near zero, highlights a specific limitation of monetary intervention in severe downturns.

Teoria keynesiana vs. Economia Clássica

Teoria keynesiana fundamentally diverges from Economia Clássica primarily in its view of how market economies function without intervention. Classical economics, which predated Keynes, generally held that free markets would naturally self-correct to full employment through flexible wages and prices. Any unemployment was seen as voluntary or temporary. Supply was believed to create its own demand (Say's Law).

In contrast, Teoria keynesiana rejects the notion of automatic full employment. Keynes argued that wages and prices are often "sticky" downward, meaning they do not adjust quickly enough to clear markets, leading to involuntary unemployment. For Keynesians, aggregate demand drives the economy, and insufficient demand can lead to persistent underemployment of resources. While classical economists advocated for minimal government intervention, Keynesians championed active fiscal and monetary policies to stabilize the economy and manage business cycles.

FAQs

What is the main idea behind Teoria keynesiana?

The main idea is that total spending in the economy, or aggregate demand, determines the overall level of economic activity and employment. When demand is too low, governments should intervene to boost it.

How does Teoria keynesiana propose to fix a recession?

Teoria keynesiana proposes that governments combat a recession by increasing government spending (e.g., infrastructure projects) or cutting taxes (fiscal policy), and by central banks lowering interest rates or increasing the money supply (monetary policy) to stimulate demand.

Is Teoria keynesiana still relevant today?

Yes, Teoria keynesiana remains highly relevant. Its principles frequently guide policymakers' responses to economic downturns, such as the use of stimulus packages during recessions or the implementation of expansionary monetary policies by central banks. While other schools of thought have emerged and refined economic understanding, core Keynesian concepts continue to inform contemporary macroeconomics.