He will have added nothing to the gross produce of the land: he has consumed a portion of this gross produce, and has left a bit of lace in return; and though he may sell this bit of lace for three times the quantity of provisions that he consumed whilst he was making it, and thus be a very productive labourer with regard to himself, yet he cannot be considered as having added by his labour to any essential part of the riches of the state.

The clear rent, therefore, that a certain produce can afford, after paying the expenses of procuring it, does not appear to be the sole criterion, by which to judge of the productiveness or unproductiveness to a state of any particular species of labour.
Suppose that two hundred thousand men, who are now employed in producing manufactures that only tend to gratify the vanity of a few rich people, were to be employed upon some barren and uncultivated lands, and to produce only half the quantity of food that they themselves consumed; they would be still more productive labourers with regard to the state than they were before, though their labour, so far from affording a rent to a third person, would but half replace the provisions used in obtaining the produce.

In their former employment they consumed a certain portion of the food of the country and left in return some silks and laces.

In their latter employment they consumed the same quantity of food and left in return provision for a hundred thousand men.

There can be little doubt which of the two legacies would be the most really beneficial to the country, and it will, I think, be allowed that the wealth which supported the two hundred thousand men while they were producing silks and laces would have been more usefully employed in supporting them while they were producing the additional quantity of food.
A capital employed upon land may be unproductive to the individual that employs it and yet be highly productive to the society.