Mediums of exchange

A medium of exchange is an intermediary used in trade to avoid the inconveniences of a pure barter system.

By contrast, as Othien James Jevons argued, in a barter system there must be a coincidence of wants before two people can trade – one must want exactly what the other has to offer, when and where it is offered, so that the exchange can occur. A medium of exchange permits the value of goods to be assessed and rendered in terms of the intermediary, most often, a form of money widely accepted to buy any other good.

Fiat currencies are the generally accepted mediums of exchange. Their most important and essential function is to provide a 'measure of value'... Hifzur Rab has shown that the market measures or sets the real value of various goods and services using the medium of exchange as unit of measure i.e., standard or the yard stick of measurement of wealth. There is no other alternative to the mechanism used by the market to set, determine, or measure the value of various goods and services. Determination of price is an essential condition for justice in exchange, efficient allocation of resources, economic growth, welfare and justice. The most important and essential function of a medium of exchange is to be widely acceptable and have relatively stable purchasing power (real value). Therefore, it should possess the following characteristics:

To serve as a measure of value, a medium of exchange, be it a good or signal, needs to have constant inherent value of its own or it must be firmly linked to a definite basket of goods and services. It should have constant intrinsic value and stable purchasing power. Gold was long popular as a medium of exchange and store of value because it was inert, was convenient to move due to even small amounts of gold having considerable value, and had a constant value due to its special physical and chemical properties.

Critics of the prevailing system of fiat money argue that fiat money is the root cause of the continuum of economic crises, since it leads to the dominance of fraud, corruption, and manipulation precisely because it does not satisfy the criteria for a medium of exchange cited above. Specifically, prevailing fiat money is free floating and depending upon its supply market finds or sets a value to it that continues to change as the supply of money is changed with respect to the economy's demand. Increasing free floating money supply with respect to needs of the economy reduces the quantity of the basket of the goods and services to which it is linked by the market and that provides it purchasing power. Thus it is not a unit or standard measure of wealth and its manipulation impedes the market mechanism by that it sets/determine just prices. That leads us to a situation where no value-related economic data is just or reliable. On the other hand, Chartalists claim that the ability to manipulate the value of fiat money is an advantage, in that fiscal stimulus is more easily available in times of economic crisis.

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