It is, however, in the present low state of economical knowledge, often possible for Governments to venture on an issue of currency, when they could not venture on an additional loan or tax, because the real operation of such issue is not understood by the people, and the pressure of it is irregularly distributed, and with an unperceived gradation. Finally, the use of substances of intrinsic value as the materials of a currency, is a barbarism;--a remnant of the conditions of barter, which alone can render commerce possible among savage nations. It is, however, still necessary, partly as a mechanical check on arbitrary issues; partly as a means of exchanges with foreign nations. In proportion to the extension of civilization, and increase of trustworthiness in Governments, it will cease. So long as it exists, the phenomena of the cost and price of the articles used for currency, are mingled with those of currency itself, in an almost inextricable manner; and the worth of money in the market is affected by multitudinous accidental circumstances, which have been traced, with more or less success, by writers on commercial operations; but with these variations the true political economist has no more to do than an engineer fortifying a harbour of refuge against Atlantic tide, has to concern himself with the cries or quarrels of children who dig pools with their fingers for its ebbing currents among the sand. SECTION III.--RICHES. According to the various industry, capacity, good fortune, and desires of men, they obtain greater or smaller share of, and claim upon, the wealth of the world. The inequalities between these shares, always in some degree just and necessary, may be either restrained by law (or circumstance) within certain limits; or may increase indefinitely. Where no moral or legal restraint is put upon the exercise of the will and intellect of the stronger, shrewder, or more covetous men, these differences become ultimately enormous. But as soon as they become so distinct in their extremes as that, on one side, there shall be manifest redundance of possession, and on the other manifest pressure of need,--the terms "riches" and "poverty" are used to express the opposite states; being contrary only in the manner of the terms "warmth" and "cold"; which neither of them imply an actual degree, but only a relation to other degrees, of temperature.