The introduction of money does not interfere with the operation of any of the laws of value. Things which by barter would exchange for one another will, if sold for money, sell for an equal amount of it, and so will exchange for one another, still through the process of exchanging them will consist of two operations instead of one. Money is a commodity, and its value is determined like that of other commodities, temporarily by demand and supply and permanently by cost of production. Credit, as a substitute for money, is but a transfer of capital from hand to hand, generally from persons unable to employ it to hands more competent to employ it efficiently in production. Credit is not a productive power in itself, though without it the productive powers already existing could not be brought into complete employment. In international trade we find that the law that permanent value is proportioned to cost of production does not hold good between commodities produced in distant places as it does in those produced in adjacent places. Between distant places, and especially between different countries, profits may continue different, because persons do not usually remove themselves or their capital to a distant place without a very strong motive. If capital removed to remote parts of the world as readily, and for as small an inducement, as it moves to another quarter of the same town, profits would be equivalent all over the world, and all things would be produced in the places where the same labour and capital would produce them in greatest quantity and of best quality. A tendency may even now be observed towards such a state of things; capital is becoming more and more cosmopolitan. It is not a difference in the _absolute_ cost of production which determines the interchange between distant places, but a difference in the _comparative_ cost. We may often by trading with foreigners obtain their commodities at a smaller expense of labour and capital than they cost to the foreigners themselves. The bargain is advantageous to the foreigner because the commodity which he receives in exchange, though it has cost us less, would probably have cost him more. The value of a commodity brought from a distant place does not depend on the cost of production in the place from whence it comes, but on the cost of its acquisition in that place; which in the case of an imported article means the cost of production of the thing which is exported to pay for it. In other words, the values of foreign commodities depend on the terms of international exchange, which, in turn, depend on supply and demand.