When the most fertile and best situated lands have been all occupied, less profit can be made by the cultivation of what is inferior both in soil and situation, and less interest can be afforded for the stock which is so employed.
 Adam Smith, The Wealth of Nations (1776). copy citation

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Author Adam Smith
Source The Wealth of Nations
Topic profit interest
Date 1776
Language English
Reference An Inquiry into the Nature and Causes of the Wealth of Nations
Note
Weblink http://www.gutenberg.org/files/3300/3300-h/3300-h.htm

Context

“Its rapid accumulation in so profitable an employment enables the planter to increase the number of his hands faster than he can find them in a new settlement. Those whom he can find, therefore, are very liberally rewarded. As the colony increases, the profits of stock gradually diminish. When the most fertile and best situated lands have been all occupied, less profit can be made by the cultivation of what is inferior both in soil and situation, and less interest can be afforded for the stock which is so employed. In the greater part of our colonies, accordingly, both the legal and the market rate of interest have been considerably reduced during the course of the present century. As riches, improvement, and population, have increased, interest has declined.” source