The quantity theory of money states that the quantity of money is the main determinant of the price level or the value of money. Any change in the quantity of money produces an exactly proportionate change in the price level. In the words of Irving Fisher, “Other things remaining unchanged, as the quantity of money in circulation increases, the price level also increases in direct proportion and the value of money decreases and vice versa.” If the quantity of money is doubled, the price level will also double and the value of money will be one half. On the other hand, if the quantity of money is reduced by one half, the price level will also be reduced by one half and the value of money will be twice. Fisher has explained his theory in terms of his equation of exchange: PT=MV+ M’ V’ : Where P = price level, or 1 IP = the value of money; M = the total quantity of legal tender money; V = the velocity of circulation of M; M’ – the total quantity of credit money; V’ = the velocity of circulation of M; T = the total amount of goods and services exchanged for money or transactions performed by money. This equation equates the demand for money (PT) to supply of money (MV=M’V). The total volume of transactions multiplied by the price level (PT) represents the demand for money. According to Fisher, PT is SPQ. In other words, price level (P) multiplied by quantity bought (Q) by the community (S) gives the total demand for money. This equals the total supply of money in the community consisting of the quantity of actual money M and its velocity of circulation V plus the total quantity of credit money M’ and its velocity of circulation V’. Thus the total value of purchases (PT) in a year is measured by MV+M’V’. Thus the equation of exchange is PT=MV+M’V’. In order to find out the effect of the quantity of money on the price level or the value of money, we write the equation as P= (MV+M’V’)/T Fisher points out the price level (P) (M+M’) provided the volume of tra remain unchanged. The truth of this proposition is evident from the fact that if M and M’ are doubled, while V, V and T remain constant, P is also doubled, but the value of money (1/P) is reduced to half. Criticisms of the Theory: The Fisherian quantity theory has been subjected to severe criticisms by economists. 1. Truism: According to Keynes, “The quantity theory of money is a truism.” Fisher’s equation of exchange is a simple truism because it states that the total quantity of money (MV+M’V’) paid for goods and services must equal their value (PT). But it cannot be accepted today that a certain percentage change in the quantity of money leads to the same percentage change in the price level. 2. Other things not equal:: The direct and proportionate relation between quantity of money and price level in Fisher’s equation is based on the assumption that “other things remain unchanged”. But in real life, V, V and T are not constant. Moreover, they are not independent of M, M’ and P. Rather, all elements in Fisher’s equation are interrelated and interdependent. For instance, a change in M may cause a change in V. Consequently, the price level may change more in proportion to a change in the quantity of money. Similarly, a change in P may cause a change in M. Rise in the price level may necessitate the issue of more money. Moreover, the volume of transactions T is also affected by changes in P. When prices rise or fall, the volume of business transactions also rises or falls. Further, the assumptions that the proportion M’ to M is constant, has not been borne out by facts. Not only this, M and M’ are not independent of T. An increase in the volume of business transactions requires an increase in the supply of money (M and M’). 3. Constants Relate to Different Time: Prof. Halm criticises Fisher for multiplying M and V because M relates to a point of time and V to a period of time. The former is a static concept and the latter a dynamic. It is therefore, technically inconsistent to multiply two non-comparable factors. 4. Fails to Measure Value of Money: Fisher’s equation does not measure the purchasing power of money but only cash transactions, that is, the volume of business transactions of all kinds or what Fisher calls the volume of trade in the community during a year. But the purchasing power of money (or value of money) relates to transactions for the purchase of goods and services for consumption. Thus the quantity theory fails to measure the value of money. 5. Weak Theory: According to Crowther, the quantity theory is weak in many respects. First, it cannot explain ’why’ there are fluctuations in the price level in the short run. Second, it gives undue importance to the price level as if changes in prices were the most critical and important phenomenon of the economic system. Third, it places a misleading emphasis on the quantity of money as the principal cause of changes in the price level during the trade cycle. Prices may not rise despite increase in the quantity of money during depression; and they may not decline with reduction in the quantity of money during boom. Further, low prices during depression are not caused by shortage of quantity of money, and high prices during prosperity are not caused by abundance of quantity of money. Thus, “the quantity theory is at best an imperfect guide to the causes of the trade cycle in the short period” according to Crowther.