The more highly developed the division of labor is, the more frequent and necessary do exchanges become. While the hermit engaged in production thinks only of his own wants, and the mere housekeeper of the wants of his household, the man who is part of a nation and who plays a part in its general economy, must bear in mind the MARKET in which goods of one kind are exchanged against goods of other kinds. The greater, more various and more changeable the conditions of this market are, the greater are the intellectual faculties demanded to engage in it successfully, and to the advantage of everybody concerned in it.(569) Goods intended to be exchanged are called commodities. By the circulation of commodities is meant their going over from one owner to another.(570) Among the principal causes of circulation, we may mention the difference in the nature and civilization of countries and peoples, the distinction between city and country, the division of people into classes etc.(571) The rapidity of circulation depends, on the one hand, on the quantity of commodities, and on the other, on the degree to which the division of labor has been carried. In both respects it is, therefore, an important indication of the wealth of the nation, and of the world. Different commodities have very different degrees of capacity for circulation (_Circulationsfähigkeit_), that is, of certainty of finding purchasers, and of facility of seeking purchasers. The smaller, compared with its value, the volume and weight of a commodity are; the longer and more conveniently it can be stored away; the more invariable and well-known are its value in use and value in exchange: the more readily does it go from one place to another, the more easily is it transmitted from one period of time to another and from the possession of one person into the possession of another. Thus, for instance, the precious metals circulate more rapidly than industrial products; these in turn more than raw material,(572) and immovable property circulates least rapidly of all. An improvement in the means of transportation naturally increases the capacity of circulation of the entire wealth of a people, and especially of those commodities which were not before transferable as well as of those of which the cost of transportation constituted a peculiarly large component part of the price.(573) The greater the capacity for circulation of any kind of goods, the greater is the power of control of its owner in the world of trade. If we compare two men, each of whom possesses a million of dollars, but one of whom has that million in money and the other in land, we shall find that the former is able, for present purposes, such as loaning to the state in case of need, aiding a conspiracy etc., to command resources much more readily and effectively than the latter. Under the ordinary circumstances of a nation’s economy, we find that the owner of money is very seldom in want of bread, fuel or