The fundamental difference between Keynes and Wicksell and in general the

supporters of the LFT [Loanable Funds Theory] lies in the specification of the consequences of the presence of bank money. Introducing the distinction between the natural rate of interest and interest rate on money, Wicksell and the LFT supporters state that an economy that uses bank money converges towards the equilibrium position that characterises an economy without banks, in which there is no credit market, but just a capital market where the resources not consumed by savers are exchanged. The presence of bank money does not alter the structure of the economic system; the only element that distinguishes a pure credit economy is the presence of an adjustment mechanism that drives the rate of interest on money, determined within the credit market, towards the natural rate of interest. The working of a pure credit economy can therefore be described using a theory that applies to a world without banks.

In contrast, Keynes states that the spread of a fiat money such as bank money changes the structure of the economic system. He underscores this point by introducing the distinction between a real exchange economy and a monetary economy. As is well known, Keynes uses the former term to refer to an economy in which money is merely a tool to reduce the cost of exchange and whose presence does not alter the structure of the economic system, which remains substantially a barter economy. Keynes notes that the classical economists formulated an explanation of how the real-exchange economy works, convinced that this explanation could be easily applied to a monetary economy. He believed that this conviction was unfounded …

Giancarlo Bertocco