Nor is the demand for food limited, as in economic reasoning is frequently, but erroneously, assumed. Subsistence is often spoken of as though it were a fixed quantity; but it is fixed only as having a definite minimum. Less than a certain amount will not keep a human being alive, and less than a somewhat larger amount will not keep a human being in good health. But, above this minimum, the subsistence which a human being can use may be increased almost indefinitely. Adam Smith says, and Ricardo indorses the statement, that the desire for food is limited in every man by the narrow capacity of the human stomach; but this, manifestly, is true only in the sense that when a man’s belly is filled, hunger is satisfied. His demands for food have no such limit. The stomach of a Louis XIV., a Louis XV., or a Louis XVI., could not hold or digest more than the stomach of a French peasant of equal stature, yet, while a few rods of ground would supply the black bread and herbs which constituted the subsistence of the peasant, it took hundreds of thousands of acres to supply the demands of the king, who, besides his own wasteful use of the finest qualities of food, required immense supplies for his servants, horses and dogs. And in the common facts of daily life, in the unsatisfied, though perhaps latent, desires which each one has, we may see how every increase in the power of producing any form of wealth must result in an increased demand for land and the direct products of land. The man who now uses coarse food, and lives in a small house, will, as a rule, if his income be increased, use more costly food, and move to a larger house. If he grows richer and richer he will procure horses, servants, gardens and lawns, his demand for the use of land constantly increasing with his wealth. In the city where I write, is a man—but the type of men everywhere to be found—who used to boil his own beans and fry his own bacon, but who, now that he has got rich, maintains a town house that takes up a whole block and would answer for a first-class hotel, two or three country houses with extensive grounds, a large stud of racers, a breeding farm, private track, etc. It certainly takes at least a thousand times, it may be several thousand times, as much land to supply the demands of this man now as it did when he was poor. And, so, every improvement or invention, no matter what it be, which gives to labor the power of producing more wealth, causes an increased demand for land and its direct products, and thus tends to force down the margin of cultivation, just as would the demand caused by an increased population. This being the case, every labor-saving invention, whether it be a steam plow, a telegraph, an improved process of smelting ores, a perfecting printing press, or a sewing machine, has a tendency to increase rent. Or to state this truth concisely: