The Wealth of Nations – libro en inglés C2

AS men, like all other animals, naturally multiply in proportion to the means of their subsistence, food is always, more or less, in demand. It can always purchase or command a greater or smaller quantity of labour, and somebody can always be found who is willing to do something in order to obtain it. The quantity of labour, indeed, which it can purchase, is not always equal to what it could maintain, if managed in the most oeconomical manner, on account of the high wages which are sometimes given to labour. But it can always purchase such a quantity of labour as it can maintain, according to the rate at which that sort of labour is commonly maintained in the neighbourhood.

BUT 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.