After all the fertile land in the immediate neighbourhood of the first settlers were cultivated, if capital and population increased, more food would be required, and it could only be procured from land not so advantageously situated. – David Ricardo
By far the greatest part of those goods which are the objects of desire, are procured by labour and they may be multiplied, not in one country alone, but in many, almost without any assignable limit, if we are disposed to bestow the labour necessary to obtain them. – David Ricardo