[E]very individual spontaneously tries to find the place and the trade in which he can best increase National gain, if laws do not prevent him from doing so.
Every man seeks his own gain. This inclination is so natural and necessary that all Communities in the world are founded upon it. Otherwise Laws, punishments and rewards would not exist and mankind would soon perish altogether. The work that has the greatest value is always best paid, and what is best paid is most sought after.
As long as I can produce 6 Daler worth of goods a day in one trade, I do not willingly change to another that brings in 4. In the former case the Nation’s gain and mine was one-third more than in the latter.
It is thus undoubtedly a loss to the Nation when somebody is forced or is encouraged by public rewards to work in a trade other than the one in which he earns the highest profit; for this does not happen without such inducements, just as a merchant does not sell his Wares for less than what is offered him.
If he whose work someone has been forced to do gains as much as the worker has lost, it is not National gain; but if he gains more, only the difference is the gain of the Nation, but obtained through the oppression of its citizens.