"Such parts only of the produce of land," says Adam Smith, "can commonly be brought to market, of which the ordinary price is sufficient to replace the stock which must be employed in bringing them thither, together with its ordinary profits. If the ordinary price is more than this, the surplus part of it will naturally go to the rent of land. _If it is not more, though the commodity can be brought to market, it can afford no rent to the landlord._ Whether the price is, or is not more, depends upon the demand." This passage would naturally lead the reader to conclude that its author could not have mistaken the nature of rent, and that he must have seen that the quality of land which the exigencies of society might require to be taken into cultivation would depend on "_the ordinary price of its produce," whether it were "sufficient to replace the stock, which must be employed in cultivating it, together with its ordinary profits_." But he had adopted the notion that "there were some parts of the produce of land for which the demand must always be such as to afford a greater price than what is sufficient to bring them to market;" and he considered food as one of those parts. He says, that "land, in almost any situation, produces a greater quantity of food than what is sufficient to maintain all the labour necessary for bringing it to market, in the most liberal way in which that labour is ever maintained. The surplus too is always more than sufficient to replace the stock which employed that labour, together with its profits. Something, therefore, always remains for a rent to the landlord."