The Wealth of Nations by Part 2 Chapter 2 Page 66

time exceeded the quantity of gold and silver which he would otherwise have been obliged to keep by him for answering occasional demands; and that, consequently, the paper money, which they had circulated by his means, had not at any time exceeded the quantity of gold and silver which would have circulated in the country had there been no paper money.

The frequency, regularity, and amount of his repayments would sufficiently demonstrate that the amount of their advances had at no time exceeded that part of his capital which he would otherwise have been obliged to keep by him unemployed and in ready money for answering occasional demands; that is, for the purpose of keeping the rest of his capital in constant employment. It is this part of his capital only which, within moderate periods of time, is continually returning to