Edward
Shapiro
MACROECONOMIC ANALYSIS
Chapter 17: The Classical Theory
Index THE CLASSICAL THEORY The Level of Output and
Employment in Classical Theory Say’s
Law The Quantity Theory of
Money
The Quantity Theory as a Theory of the Price
Level The Quantity Theory as a Theory of Aggregate Demand Classical Model without
Saving and Investment
Effects of a Change in the Supply of Money
Effect of a Change in the Supply of Labor
Effects of a Change in the Demand for Labor
Effects of a Rigid Money Wage Monetary Policy and Full Employment Web 4
Classical Model with Saving
and Investment |
CLASSICAL MODEL WITH SAVING
AND INVESTMENT
Although formally correct,
the classical model we have been discussing is oversimplified because it fails
to break aggregate demand down into demand for consumption goods and demand for
capital goods. This means that it
does not recognize the processes of saving and
investment.
We must now recognize that
not every dollar of income earned in the course of production is spent for
consumption goods; some part of this income is withheld from consumption, or
saved. Clearly, unless there is a
dollar of planned investment spending for every dollar of income saved, Say’s
Law is invalidated. Another part of
classical theory provides the mechanism that presumably assures that planned
saving will not exceed planned investment.
This mechanism is the rate
of interest. Classical theory
treated saving as a direct function of the rate of interest and investment as an
inverse function, as illustrated in Figure 17-6. The investment curve is simply the curve
of the marginal efficiency of investment (MET), whose derivation was explained
in some detail in Chapter 11. There
it was a part of our development of Keynesian theory; here we see that this was
actually a part of the classical theory taken over by Keynes. It is important to note, however, that
although both theories show investment as an inverse function of the rate of
interest, this is not to say that both assign equal importance to the rate of
interest as an influence on investment spending. The whole question of the elasticity of
the investment demand schedule is involved, a topic we discussed at length in
Chapter 13. Keynes and most
economists since Keynes have argued that the curve is relatively inelastic.
If it is elastic, a relatively
small change in the rate of interest will be sufficient to call forth a
relatively large change in investment; relatively small changes in the rate of
interest will then be all that are required to keep planned saving and planned
investment in balance as the saving and investment schedules shift. If it is inelastic, relatively large
changes in the rate of interest will be required for this purpose. 14
The question then arises
as to whether the
14. It is also conceivable
that both the investment and saving curves are so inelastic that a shift to the
right in the saving curve or a shift to the left in the investment curve or a
combination of the two may result in an intersection of the two curves only at a
negative rate of interest. However
low the rate of interest might fall, it assuredly could not fall below zero.
The result is an impasse at which
the rate of interest is completely powerless to equate saving and
investment. See W.S. Vickrey,
op. cit., pp. 172-73.
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rate of interest will
fluctuate freely over the wider range necessary to equate saving and investment.
To simplify the exposition of the
classical system, let us assume here that the curve is indeed elastic, so that
investment is relatively responsive to changes in the rate of interest. Small changes will then keep saving and
investment in balance.
The saving curve of Figure
17-6 is new. Here saving is made a
direct function of the interest rate; in Keynesian theory, saving is a direct
function of the level of income. The rate of interest may have an
influence on saving, but it is of minor importance in the Keynesian scheme.
In classical theory, the rate of
interest is all important, and the level of income is of minor importance. Since the classical model argues that
full employment is the normal state of affairs in the economy, the level of
income is in effect ruled out as a variable in the short run, and so it is ruled
out as an influence on the amount of saving. The problem in classical economics is to
explain how saving will vary at the full-employment level of income, and the
solution is provided by the rate of interest. The higher the rate of interest, the
greater the amount of the full-employment income that is withheld from
consumption or devoted to saving.
Given saving and investment
curves such as S and I of Figure 17-6,
competition between savers and investors would move the rate of interest to the
level that equated saving and investment. If the rate were above r1, there would be more funds
supplied by savers than demanded by investors, and the competition among savers
to find investors would force the rate down. If the rate were below r1,
competition would force the rate up. When the rate is at r1, equilibrium
is established, with every dollar saved or withheld from consumption spending
matched by a dollar borrowed and devoted to investment
spending.
It is important to see that
this transfer of money from savers to investors also involves a transfer of
resources. The decision to save
part of current income is a decision by income recipients not to exercise their
claims to the full amount of output that results from their productive services.
This releases resources from the
production of consumption goods and makes them available for the production of
capital goods. These resources will
be fully absorbed in the production of capital goods only if investors choose to
purchase exactly the amount
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of capital goods that can
be produced by the resources released as a result of saving. This means that if the rate of interest
were above r1 and somehow stayed above r1, unemployed
resources would appear, for the excess of S over I at an interest rate above
r1 reflects, in real terms, an excess of resources released
from the production of consumption goods over the amount absorbed in the
production of capital goods. One of
these resources is, of course, labor, and the excess of S over I also means that there is
an excess of labor available over labor employed. In a word, there is unemployment. Thus, in the classical system, if the
rate of interest fails to equate saving and investment, it also fails in its
assigned task of promptly reallocating the resources released from production of
consumption goods to the production of capital goods, and unemployed resources
are the result.
Changes in Saving and
Investment
As long as the interest
rate adjusts upward and downward to correct any disequilibrium, shifts in the
saving and investment functions will lead to the establishment of new
equilibrium positions. Suppose that
income recipients become more thrifty; at each rate of interest they choose to
save a larger part of their current income. This appears in Figure 17-6 as a shift to
the right from S to S’ in the saving curve and a decrease in
the rate of interest from r1 to the new equilibrium level
r2. A numerical
example such as those presented earlier is given below to bring out the effects
of an increase in thrift in the classical system. The first row indicates the values of the
variables at the original full-employment equilibrium. Full employment of the labor force is
N of 100, and full-employment output is O of 300. With the interest rate at
r1, say 6 percent, the real income of 300 was divided into 250
of consumption and 50 of saving; r of 6 percent also produced
equilibrium with saving of 50 and investment of 50. If the saving curve
now shifts to the right and the interest rate drops to r2, say 4
percent, a new equilibrium is established at which saving of 75 (in real terms,
O of 300 less C of 225) equals investment
of 75. With no shift in the
production function or the supply of labor, full-employment output remains at
300. The only change is in the
distribution of output from 250 of consumption goods and 50 of capital goods to
225 of consumption goods and 75 of capital goods. Thus we see that the increased
thriftiness of the public has produced a reallocation of resources - one away
from the production of consumption goods and to the production of capital goods
- but with the total production of goods unchanged at the full-employment level
of 300.
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If the saving function
shifted in the opposite direction so that there was less saving at each rate of
interest, we would have a higher rate of interest at which a smaller flow of
saving would be equated with a smaller flow of investment but still with the
flow of aggregate output unchanged from the full-employment level with which we
started. The effects of shifts in
the investment curve resulting from shifts in the MEC curve may be traced in the
same way. Whatever the shifts in
the saving and investment curves, however, the possibility of “oversaving” or
“underconsumption” could not arise as long as the interest rate succeeded in
balancing saving and investment.
Does the interest rate
always promptly adjust as required to maintain equality between saving and
investment? The Swedish economist
Knut Wicksell (1851-1926)
was one of the first to point out that there are conditions under
which it would not. However, the
full-employment conclusion would still result if prices and wages were
sufficiently flexible. If the
interest rate did not promptly adjust, there would be an excess of planned
saving over planned investment or planned investment over planned saving. According to Keynesian theory, a fall or
rise in income (output and employment) would be required at this point to bring
saving and investment back into balance. This was not the case in classical
theory, however. An excess of
saving over investment would mean a deficiency of aggregate demand at the
existing price level. This would
lead to a deflation of prices and wages but would not interfere with the
maintenance of the real wage consistent with full employment. Aggregate demand that had become
deficient at the original price level would now be adequate to purchase the
full-employment level of output at a lower price level. Conversely, an excess of planned
investment over planned saving would mean an excess of aggregate demand at the
existing price level. This would
lead to an inflation of prices and wages but again would not interfere with the
maintenance of the real wage consistent with full
employment.
The purpose of this chapter
has been to show, in terms of a simple model, how classical theory answered the
fundamental questions of macroeconomics. What determines the levels of employment,
output, consumption, saving, investment, prices, and wages? Our discussion may now be summarized in a
list of the basic propositions that make up classical theory. Each of these propositions will be
related to the graphic apparatus of Figure 17-7, which adds nothing new but
brings together the saving-investment branch of the classical system with its
other branches, presented in two steps in the preceding pages.
-
1. As shown in Part B, the supply, SL, and demand, DL, for labor are both
functions of the real wage, W/P.
Because of diminishing
returns, the demand curve slopes downward to the right (i.e., more labor is
hired only at a lower real wage). Because of the essential
disagreeableness of work, the supply curve slopes upward to the right (i.e.,
more labor is offered only at a higher real wage).
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The intersection of the
supply and demand curves thus determines both the real wage (W/P)1 and the level of
employment N1.
2. With fixed techniques of
production and fixed capital stock, output in the short run becomes a function
of employment, as shown by the production function in Part A. With employment determined in Part B as
N1, output is determined
in Part A as O1.
3. The price level, P, is determined by the supply of money,
M, the curve MV in Part C defining the particular
supply of money and a stable velocity of money. With output determined in Part A as O1, the price level of that
output is determined on Part C as P1.
4. The money wage, W, adjusts to the price level to produce
the real wage required for equilibrium.
With the equilibrium real wage determined in Part B as (W/P)1 and the price level
determined in Part C as P1, the required money wage
is determined in Part D as W1.
5. As shown in Part E,
saving, S, is a direct function of
the rate of interest; and investment, I, is an inverse function of the
rate of interest. With the rate of
interest as a measure of the reward for saving, the higher the rate of interest
the greater will be the volume of saving.
With the interest rate as the “price” of capital goods, the lower the
interest rate, the greater will be the volume of
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investment. The rate of interest is determined by the
intersection of the saving and investment functions, and it determines how real
income is allocated between saving and consumption and how production (equal to
real income) is allocated between consumption goods and capital
goods.
These propositions are the
basis for answers to the questions originally posed. But another equally important question
lies behind the first and most critical one: Will the level of employment be
that which equates the supply of and the demand for labor? Will it be the full-employment level?
An affirmative answer to this
question follows in classical theory as soon as we add a final
proposition:
6. Both prices and wage are
flexible, which simply means that the money wage will fall if unemployment
appears, and the price level will fall if the existing level of output cannot be
sold at going prices. If such
flexibility does in fact exist, then the automatic full-employment conclusion
follows logically. It also follows
that output will be that which can be produced with a fully employed labor
force, that the price level will be that at which the money supply with its
given velocity will purchase this full-employment level of output, and that the
money wage will be so related to the price level as to make it profitable for
employers to produce the full-employment level of
output.
The classical conclusion
that the economy has an automatic tendency to move toward a full-employment
equilibrium is not widely accepted today. But this and other conclusions of
classical employment theory can be rejected only by rejecting the assumptions on
which that theory rests, for the theory itself appears to be internally
consistent. Once its assumptions
are granted, the theory inevitably leads to the indicated
conclusions.
We will not enter here into
Keynes’s specific attack on the assumptions that underlie classical theory, but
most economists agree that his attack was successful. Not only did he offer persuasive
arguments against these critical assumptions, but he replaced the rejected
assumptions with others that appeared much more consistent with the facts of
ordinary observation and statistical evidence. To the extent that the assumptions on
which the classical theory was based could be shown to be unacceptable, the
conclusions, including the automatic full-employment conclusion, reached by that
theory also became unacceptable.
A CONCLUDING
NOTE
If the classical analysis
of the process by which the levels of employment, output, and prices are
determined is unacceptable, at least in its application to the modern economy,
it may appear that this lengthy chapter is basically unnecessary. To this there are a number of
replies.
First, it is not altogether
correct to label the classical theory of employment. output. and prices as
unacceptable or in some sense
“wrong”. Since the aim of this chapter was to do
no more than introduce the broad outlines
of
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that theory, it could do no
more than draw broad conclusions and compare these with the somewhat more
detailed conclusions so far derived from our study of Keynesian theory. The omission of refinements that would
give us a more accurate picture of classical theory leaves us with little choice
but to categorize the basic propositions of classical theory as correct or
incorrect, and such categorization is itself inherently incorrect. Alfred Marshall once said that every
short statement about economics is misleading (with the possible
exception of this one). Our
statement here, relative to what is involved in a complete treatment, is such a
short statement and unavoidably somewhat
misleading.
Second, one’s understanding
of a new theory is surely enriched when that theory is contrasted with the old
theory that it seeks to displace. The classical system was the accepted
explanation of macroeconomic phenomena for well over a hundred years. A discussion of this theory, which is
partially correct and a product of the not so distant past, helps us understand
and appreciate the changes in macroeconomic theory that have occurred since the
Great Depression.
Finally, it is important to
note that, despite the dramatic success of Keynesian theory over the past three
decades, classical theory is still the theory on which many men in positions of
great responsibility, both in government and business, were raised. It is not even necessary for them to have
received formal training in economics as young men - the stuff of which
economics is made has a way of permeating men’s minds and influencing their
outlooks without any awareness on their part. At the very end of the General Theory,
Keynes expressed this thought in what has come to be a much-quoted
statement:
the ideas of economists and
political philosophers, both when they are right and when they are wrong, are
more powerful than is commonly understood. Indeed the world is ruled by little else.
Practical men, who believe
themselves to be quite exempt from any intellectual influences, are usually the
slaves of some defunct economist. Madmen in authority, who hear voices in
the air, are distilling their frenzy from some academic scribbler of a few years
back. 15
The defunct economists who
continue to influence many of these men today are the economists who constructed
the classical theory.
In a similar vein, we find
the very last sentence in Alexander Gray’s classic little handbook on economic
thought:
No point of view, once
expressed, ever seems wholly to die; and in periods
of transition like the
present, our ears are full of the whisperings of dead
men.16
For more than one reason,
the teachings of the classical economists are of something more than historical
interest today. The few reasons
here given should be sufficient to make this point. The “Keynesian Revolution” did not so
completely wipe out the “old order” that no sign of it remains today. So far at least, for both academic and
practical reasons, a proper introduction to macroeconomic theory should include
the fundamentals of the theory that held sway for more than a century before
Keynes.
15. General Theory, p.
383.
16. The Development of Economic Doctrine,
Longman, Green, 1931, p. 370.
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End of Chapter