A thousand ploughmen consume fully as much corn and cloth in the course of a year as a regiment of soldiers. But the difference between the kinds of consumption is immense. The labour of the ploughman has, during the year, served to call into existence a quantity of property, which not only repays the corn and cloth which he has consumed, but repays it with a profit. The soldier on the other hand produces nothing. What he has consumed is gone, and its place is left absolutely vacant. The country is the poorer for his consumption, to the full amount of what he has consumed. It is not the poorer, but the richer for what the ploughman has consumed, because, during the time he was consuming it, he has reproduced what does more than replace it.
— James Mill in Commerce Defended (1808).