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Interest is the use fee of money in a certain period of time, and it refers to the reward that money holders (creditors) get from borrowers (debtors) for lending money or monetary capital. Including deposit interest, loan interest and interest generated by various bonds. Under the capitalist system, the source of interest is the surplus value created by hired workers. The essence of interest is a special transformation form of surplus value and a part of profit.
theoretical basis
Marx's Political Economy Viewpoint
According to Marxism, interest is actually a part of profit and a transformation form of surplus value. Money itself cannot create money, nor will it increase in value by itself. Only when functional capital buys means of production and labor with money can it create surplus value through the labor of hiring workers in the production process. Monetary capitalists share surplus value with functional capitalists by virtue of their capital ownership. Therefore, the separation of capital ownership and capital use right is the inherent premise of interest generation. Due to the characteristics of reproduction process, the coexistence of capital surplus and capital shortage is the external condition for interest generation. Money becomes capital when it is possessed by capitalists and used as a means to exploit the surplus value of hired workers. Money performs the function of capital and gains additional use value, that is, the ability to generate average profits. All capitalists are driven by the interests of pursuing surplus value, and profits are converted into average profits. The average profit is divided into interest and income of business owners, which are owned by different capitalists. Therefore, interest, like profit in essence, is the transformation form of surplus value, which reflects the relationship between loan capitalists and functional capitalists who jointly exploit workers.
Western economic viewpoint
The theory of actual interest is the actual restraint of remuneration and actual qualifications. Interest theory has always been in a dominant position in the field of interest research.
Monetary interest theory holds that interest is the cost of borrowing money and selling securities, as well as the income from borrowing and buying securities. As a monetary phenomenon, interest rate is completely determined by the relationship between supply and demand of money. China scholars believe that in a socialist society with public ownership as the main body, benefits come from the value-added part of national income or social wealth. In real life, interest is regarded as the general form of income, which leads to the capitalization of income.