CHAPTER VI.

ON MEASURES OF VALUE.

WE now come to the consideration of a subject which has made a conspicuous figure in the writings of political economists, and than which, none perhaps has been a greater source of error and confusion; I mean the measurement of value.

Our first inquiry must therefore be directed to the signification of the term. The analogies suggested by the word measure seem to have bewildered almost every author who has touched on the subject. It has been taken for granted

that we measure value as we measure extension, or ascertain weight; and it has been consequently imagined, that to perform the opera

tion we must possess an object of invariable

value.

Let us examine, therefore, how far measuring value and measuring space are similar operations. In every case of measuring we merely ascertain ratios-the ratio which one thing bears to another. In measuring the length of an object we find what ratio it bears to the length of some other object, or in other words, how many times one is contained in the other. We measure the longitudinal extension of a piece of timber, for example, by a footrule; that is, we find how often the length of the latter is contained in the former, and this is effected by the actual application of the rule to the timber. It is a physical operation, by which we obtain the knowledge of a fact before unknown, the ratio of length subsisting between the object and the instrument we employ.

In measuring value, what resemblance to this operation can possibly be discovered? We may place two objects by the side of each other, or apply one to the other in any way we please,

but we shall never be able by such means to discover the relation of value existing between them. We shall never extort from them a single fact with which we were before unacquainted. What then is it possible to do in the way of measuring value? What kind of measurement is intended, when the term is so frequently employed? All that is practicable appears to be simply this: if I know the value of a in relation to B, and the value of в in relation to c, I can tell the value of a and c in relation to each other, and consequently their comparative power in purchasing all other commodities. This is an operation obviously bearing no resemblance at all to the process of measuring length. There is no unknown fact discovered by a physical operation: it is in truth a calculation from certain data, a mere question in arithmetic. It is not, let it be observed, what on a first glance it may appear, like ascertaining the comparative length of two pieces of timber which cannot be brought into juxta-position, by means of a foot rule or other instrument which we apply

first to one and then to the other: it is far from being so much as this: it is merely like calculating the ratio of length between the two pieces of timber, after we are informed how many feet are contained in each. For of each commodity a and c the value in relation to B must be given, or, in other words, their value must be expressed in a common denomination, before their mutual relation can be ascertained; just as in the case supposed the relation of each piece of timber to the foot-rule must be given, before their relation to each other can be deduced. The actual application of the foot rule is that part of the process which is alone entitled to the appellation of measuring, the rest being mere calculation, but to this there is nothing at all analogous in any possible attempt to ascertain value. The way in which the commodity в would be used, in the above instance, is in truth as a medium of comparison, not a measure, yet it is the only process which bears any analogy to measurement.

It appears, therefore, that all we can under

stand by a measure of value, is some commodity which would serve as a medium to ascertain the relation subsisting between two other commodities, that we had no means of bringing into direct comparison. Thus, if I wished to know the relation in exchange between corn and cloth, and there happened to be no instance of direct barter of one of these commodities for the other, I could acquire the desired information only by ascertaining their relations to a third commodity. Supposing this commodity to be money, if a yard of cloth were worth 10s., and a bushel of corn 5s., I should learn immediately that a yard of cloth was worth two bushels of corn, and would have an equal power of commanding all other things in exchange, silver in this instance being the commodity employed as a measure. This kind of measure of value, which is merely a medium of comparison, and obviously quite dissimilar to a measure of length, is the only one which it is possible to have; and although money is the measure generally employed, and by far the