Transcript الفكر الكينزي والكلاسيكي العرض الكلي والطلب الكلي ودور الدولة

‫الجزء الرابع‬
‫الفكر الكينزي والكالسيكي‬
‫العرض الكلي والطلب الكلي ودور الدولة‬
‫‪Keynes vs. the Classicals‬‬
‫‪Aggregate Demand and Supply and the role of the‬‬
‫‪government‬‬
‫د‪.‬إقبال الرحماني‬
‫‪2001‬‬
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Keynes vs. the Classical economists
Aggregate demand & aggregate supply and the government role
Recall the main macroeconomic goals,
and review your understanding about:
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1- Economic growth
4- Potential output
2- Aggregate Supply
5- Actual output
3- Aggregate Demand
6- Business cycle
The Classical economists:
Most Classical economists (major exception Malthus) believed that
the economy operated with certain mechanisms that insured the
achievement of full employment (a self correction process) , i .e
achieving potential output. A famous representative of this belief is
known as SAY’s Law (Supply creates its own demand).
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Hence, the economy will always
be at the PPC in the long run / LR;
and actual output = potential output.
Any slow down of the economy will
only be temporary (in the short run /
SR).
‫االقتصاديون الكالسيكيون (ملخص(‬
‫أغلب المفكرين الكالسيكيين اعتقدوا أن‬
‫االقتصاد له القدرة الذاتية للوصول لحالة‬
‫التوظف الكامل‪ .‬أحد المقوالت الشهيرة‬
‫المعبرة عن هذا االعتقاد هي ما يعرف بقانون‬
‫ساى “ العرض يخلق الطلب عليه”‪ ،‬مما يضمن‬
‫الوصول لحالة توازن العرض الكلي والطلب‬
‫الكلي عند التوظف الكامل ‪ ،‬وبالتالي فإن‬
‫أي إنخفاض في معدالت النمو اإلقتصادي ستكون‬
‫مؤقتة أي فقط في األجل القصير ‪.‬‬
‫رأى المفكرون الكالسيكيون إن هناك ثالثة‬
‫آليات تصحيحيةتضمن الوصول لحالة التوظف‬
‫الكامل‪ ،‬وهي‪ :‬مرونة األسعار‪ ،‬ومرونة األجور‪،‬‬
‫وأسعار الفائدة‪.‬‬
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The Classical economists:
The Classical economists believed that aggregate demand will equal
aggregate supply. If AS > AD , and a recession occurred, it will
only be temporary (SR). In the LR three mechanisms will insure that
AD = AS . These three mechanisms are:
1- Changes in the price level: if AS > AD , and positive
inventories occurred, then the general price level will
decrease, leading to an increase in AD and a reduction of
inventories.
2- Changes in wages : if AS > AD , and unemployment
increased, then nominal wages will drop, which will
eventually increase the demand for workers and reduces
unemployment.
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The Classical economists:
3- Changes in interest rate : if AS > AD , and the saving level
is higher than investment, then interest rate will drop
leading to an increase in investment and consumption
expenditure (increasing AD) and reducing saving.
Hence,
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Since, the economy has its own internal mechanisms, to
overcome any recessionary trend and reaches full
employment, the Classical economists believed there is no
need for government intervention in the economy (Lassies
Fair).
Keynes:(1883- 1946)
Keynes major contribution at the time of the
Great Depression.
Unlike the Classical economists
Keynes did not believe that the
economy have self correcting
mechanisms to assure full
employment. He believed that the
three mechanisms the Classical
believed in, were in fact not as
flexible (sticky/ rigid) as they
thought.
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John Maynard Keynes
Keynes thought that if AS > AD, then the accumulated inventories
would lead investors to reduce output. This reduction will mean the
utilization of less factors of production, hence increasing
unemployment. A higher rate of unemployment means less income
and hence will reduce AD further. A reduction in AD, will have
more recessionary impact and AS >> AD
Keynes looked at investment expenditure as a factor affecting both
AS and AD. Investment expenditure not only changes the capital
stock and output (AS), but also changes the demand for factors of
production, and the income level, and hence the AD.
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‫كينز‬
‫على خالف أغلب المفكرين الكالسيكيين ‪ ،‬كينز لم‬
‫يؤمن أن االقتصاد يحمل آليات تصحيحية تمكنه‬
‫من الوصول لحالة التوظف الكامل‪ .‬وقد أعتبر‬
‫إن آليات األسعار واألجور غير مرنة بالشكل‬
‫الذي رآه الكالسيكيون‪.‬‬
‫ففى حالة ارتفاع العرض الكلي عن الطلب الكلي‬
‫(ركود اقتصادي) رأى كينز إن تكدس المخزون‬
‫السلعي سيدفع المنتجين لخفض اإلنتاج (وليس‬
‫األسعار) ‪ ،‬هذا الخفض يعني توظيف أقل للموارد‬
‫االقتصادية بما فيها العمل مما سيؤدي الرتفاع‬
‫معدل البطالة‪ .‬إن ارتفاع البطالة بدوره‬
‫يعني انخفاض في األجور والدخل وبالتالي‬
‫انخفاض في الطلب الكلي ومن ثم تفاقم حالة‬
‫الركود‪.‬‬
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Keynes
If AS > AD
Reduce demand for
factors of production
Increase
unemployment
Reduce income
Reduce AD
Reduce further demand for
factors of production
Higher
unemployment
Reduce income
further
AS >> AD
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Hence, the economy may be at
equilibrium blow its potential
output even in the long run /
LR. Any slow down of the
economy can continue into a
depression . The persistence of
the economic depression for
years in Europe and the USA
supported his theory.
‫إذن حسب رأي كينز إن االقتصاد يمكن أن يستقر عند مستوى أقل من‬
‫ إن استمرار حالة‬.‫التوظف الكامل (االنتاج الممكن) لفترة طويلة‬
‫الكساد في أمريكا وأوربا لسنوات طويلة تعتبر حالة تطبيقية لهذا‬
.‫الرأي‬
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AS(SR)
AD
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Keynes:
“In the long run we are all dead”
Keynes believed that the government should intervene to
assist the economy to reach full employment. This
intervention can be done through fiscal and monetary
policies, that affect directly and indirectly the aggregate
demand. Otherwise, the economy’s recession will continue
causing more unemployment.
Note: Fiscal and monetary policies can also be used to
reduce the aggregate demand to avoid inflation.
We will explore these policies later. But first examine the meaning and
impact of unemployment and inflation.
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‫على خالف المفكرين الكالسيكيين آمن كينز‬
‫بضرورة تدخل الحكومة في االقتصاد عبر‬
‫سياسات اقتصادية (السياسة المالية‬
‫والنقدية) للتأثير بشكل مباشر وغير مباشر‬
‫على الطلب الكلي للخروج من حالة الركود‬
‫االقتصادي ( أو في حاالت التضخم(‬
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