Money-capital is nothing but a sum of money, or the value of a certain quantity of commodities fixed in a sum of money. If a commodity is loaned out as capital, it is only a disguised form of a sum of money.
 Karl Marx, Das Kapital (1894). copy citation

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Author Karl Marx
Source Das Kapital
Topic loan money
Date 1894
Language English
Reference
Note
Weblink https://www.marxists.org/archive/marx/works/download/pdf/Capital-Volume-...

Context

“Interest, signifying the price of capital, is from the outset quite an irrational expression. The commodity in question has a double value, first a value, and then a price different from this value, while price represents the expression of value in money. Money-capital is nothing but a sum of money, or the value of a certain quantity of commodities fixed in a sum of money. If a commodity is loaned out as capital, it is only a disguised form of a sum of money. Because what is loaned out as capital is not so and so many pounds of cotton, but so much and so much money existing in the form of cotton as its value. The price of capital, therefore, refers to it as to a sum of money, even if not currency, as Mr. Torrens thinks (see Footnote 59).” source