Surplus product

Surplus product (German: Mehrprodukt) is an economic concept explicitly theorised by Karl Marx in his critique of political economy. Marx first began to work out his idea of surplus product in his 1844 notes on James Mill's Elements of political economy.

Notions of "surplus produce" have been used in economic thought and commerce for a long time (notably by the Physiocrats), but in Das Kapital, Theories of Surplus Value and the Grundrisse Marx gave the concept a central place in his interpretation of economic history. Nowadays the concept is mainly used in Marxian economics.political anthropology, cultural anthropology, economic anthropology

The translation of the German "Mehr" as "surplus" is in a sense unfortunate, because it might be taken to suggest "unused", "not needed" or "redundant", while literally it means "more" or "added" - thus, "Mehrprodukt" refers really to the additional or "excess" product produced. In German, the term "Mehrwert" simply and literally means value-added, a measure of net output, (though, in Marx's specialist usage, it means the surplus-value obtained from the use of capital, i.e. it refers to the net addition to the value of capital owned).

In Theories of Surplus Value, Marx says in classical economics the "surplus" referred to an excess of gross income over cost, which implied that the value of goods sold was greater than the value of the costs involved in producing or supplying them. That was how you could "make money". The surplus represented a net addition to the stock of wealth. A central theoretical question was then to explain the kinds of influences on the size of the surplus, or how the surplus originated, since that had important consequences for the funds available for re-investment, tax levies, the wealth of nations, and (especially) economic growth.

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