It is here that the _Essay on Rent_ is connected with the _Essay on Population_. By the law of population the tendency is that where food enough for six is being produced by two, the other four will soon make their appearance; and so, thinks Malthus, the farmer makes his customers by simply making his wares. Something like this, we might add, would happen in a completely developed co-operative society, where the makers would sell to each other and buy from each other. It is even true, in a sense, of all manufacturers as things now are, in proportion as their articles come near to being necessaries;—if they supply that without which people cannot live, they go far to bring people into being. Malthus, however, regarded it as much more true of agricultural production than of any other. He regarded food as the chief necessary, and thought with Adam Smith, that “when food is provided it is comparatively easy to find the necessary clothing and lodging.”[526] Against this we need only remember, how the _Essay on Population_ showed that it was only in the lower stages of existence that increase of mere food involved increase of population; and so the tendency of the supply to create its own demand was, on the author’s own showing, nothing more than a tendency.[527] His economical reasoning was swayed a little by his circumstances. The insularity of English life in his days prevented him from conceiving how a nation could safely derive half its food from abroad; what Adam Smith had thought too good to be likely,[528] he thought too dangerous to be desirable. Good or bad, it is our position now, and the result is, first, that the supply of food does not, in the same degree or way, produce its own demand as formerly, and, second, that our other productions are, even more truly than the agricultural, the supply that creates its own demand, for they give the power of buying the food that feeds new demanders. The production carried on, on the surface of the land, has come in this way to be a more potent cause of the Progress of rents than production from the soil itself. With this restatement the second of Malthus’ causes of rent becomes perhaps a little more intelligible.