The Wealth of Nations by Part 4 Chapter 9 Page 9

employments; but, from a regard to his own interest, must desert it as soon as possible and seek some other. That part of the produce of the land which is thus necessary for enabling the farmer to continue his business ought to be considered as a fund sacred to cultivation, which, if the landlord violates, he necessarily reduces the produce of his own land, and in a few years not only disables the farmer from paying this racked rent, but from paying the reasonable rent which he might otherwise have got for his land.

The rent which properly belongs to the landlord is no more than the net produce which remains after paying in the completest manner all the necessary expenses which must be previously laid out in order to raise the gross or the whole produce. It is because the labour of the cultivators, over and above paying