O N C O M P A R I N G C O M M O D I T I E S A T D I F F E R E N T
P E R I O D S .
PERHAPS no part of their investigations has perplexed political economists more than their attempts to compare the value of the same object at different periods of time.
It is a direct inference from the explanation of value in the preceding chapters, as denoting a relation between two commodities, a relation incapable of existing when there is only one commodity, that it cannot exist between a commodity at one period and the same commodity at another period. We cannot ascertain the relation of cloth at one time to cloth at another, as we can ascertain the relation of cloth to corn in the present day. All  that we can do is to compare the relation in which cloth stood at each period to some other commodity. When we say, that an article in a former age was of a certain value, we mean, that it exchanged for a certain quantity of some other commodity. But this is an inapplicable expression in speaking of only one commodity at two different periods. We cannot say, that a pair of stockings in James the First's reign would exchange for six pair in our own day; and we therefore cannot say, that a pair in James the First's reign was equal in value to six pair now, without reference to some other article.
Value is a relation between contemporary commodities, because such only admit of being exchanged for each other; and if we compare the value of a commodity at one time with its value at another, it is only a comparison of the relation in which it stood at these different times to some other commodity. It is not a comparison of some intrinsic, independent quality at one period, with the same quality at  another period; but a comparison of ratios, or a comparison of the relative quantities in which commodities exchanged for each other at two different epochs. If a commodity of in the year 100 was worth 2 B, and in 1800 was worth 4 B, we should say that A had doubled its value to B. But this, which is the only kind of comparison we can institute, would not give us any relation between A in 100 and A in 1800; it would be simply a comparison of the relation between A and B in each of those years.
It is impossible for a direct relation of value to exist between A in 100 and A in 1800, just as it is impossible for the relation of distance to exist between the sun at the former period and the sun at the latter. This perhaps will be still more apparent if we make use of the definition of value instead of the term. It will at once be seen how absurd it would be to talk of the power of A in the year 100, to command in exchange the same commodity in 1800.
It may, perhaps, be alleged, that I am here fighting with a mere shadow of my own crea-tion; for that nobody ever imagined the possibility of comparing the value of any commodity at one period with its value at another, without reference to some other object, the bare notion of such a comparison being absurd, and scarcely susceptible of being stated in intelligible language; and further, that when the value of a commodity in one year is compared with its value in another, the very terms necessarily imply a reference to other articles, and are always so considered.
A slight inspection, however, of our principal writers will prove, that if I am fighting with a shadow, which I by no means deny, it is not one of my own creation. When Mr. Ricardo tells us, that a commodity always produced by the same labour is of invariable value, he implicitly maintains all I have been attempting to disprove. By the epithet invariable he clearly means, that its value at one time will be precisely the same as its value at another, not in relation to other commodities, for he supposes all other con. modities to vary, but in relation to  itself. He distinctly states, that if equal quantities of gold could always be obtained by equal quantities of labour, the value of gold would be invariable, and it would be eminently well calculated to measure the varying value of all other things, whence it follows, that this invariableness must be intended to be affirmed of the value of gold compared with itself, and not of any relation between gold and some other commodity.
The same remarks apply to all attempts to find out something of invariable value. Adam Smith and Mr. Malthus, in considering labour alone as never varying in its own value, assert by implication, that labour at one period may be compared in value with labour at another period, without reference to any other thing whatever*. I fully concede that such a notion  involves an absurdity, that they might have talked with equal propriety of the possibility of comparing the distance of the sun in the year 100 with its distance in 1800, without reference to any other body in space and that language can scarcely be found to express the idea in direct terms, without a palpable contradiction: but that such a notion has extensively prevailed no one will doubt, who attentively turns over the pages of the first writers on the subject.
The following passage from the Templars' Dialogues on Political Economy, is a conspicuous instance of the error in question.
I wish to know, says he, whether a day's labour at the time of the English Revolution bore the same value as a hundred years after, at the time of the French Revolution, and if not the same value, whether a higher or a lower. For this purpose, if I believe that there is any commodity which is immutable in value, I shall naturally compare a day's labour with that commodity at each period. Some for instance  have imagined, that corn is of invariable value, and supposing me to adopt so false a notion, I should merely have to inquire what quantity of corn a day's labour would exchange for at each period, and I should then have determined the relations of value between labour at the two periods *.
It scarcely needs pointing out, after the explanation I have given, that no relation of value could exist between labour at these two periods: the only point to be ascertained would be, whether the same or a different relation existed at both periods, between corn and labour, and this would be equally well ascertained, without supposing the condition of corn being immutable in value. This very supposition implies, either that the fact which it is wished to ascertain is already ascertained, or, that the value of corn at one period may be compared with the value of corn at another period, with no reference to any other commodity in the world.
 Many errors appear to have arisen from this inattention to the real nature of a comparison of objects at different periods in regard to their value.
Much indistinctness has also proceeded from blending the comparison of contemporary commodities with that of the same commodity at different times, particularly when writers have been speaking of the comparative quantity, or the comparative value of the labour concerned in the production of commodities. It is not always clear to their readers, nor does it seem to have been clearer to themselves, whether they intended to compare the same commodity, as to the producing labour, at separate periods, or different commodities at the same period. There appears to me to be considerable confusion in this respect in Mr. Ricardo's first section on value; a confusion which is probably one of the latent causes of the obscurity felt by many to hang over that section, and which, if I mistake not, is perceptible in the very sentence which forms its title.
 The value of a commodity, says lie, or the quantity of any other commodity for which it will exchange, depends on the relative quantity of labour which is necessary for its production, and not on the greater or less compensation which is paid for that labour.
In the first part of this sentence he appears to be speaking of contemporary commodities, but in the latter clause he has changed his ground: it does not form a proper logical counterpart to the former: there is, I think, an implied although an unconscious reference to the same commodity at different periods. For if not, if he is speaking in the latter clause also of contemporary commodities, the amount of the proposition would be this :
The values of two contemporary commodities, A and B, are to each other as the quantities of labour necessary to their production, and they are not to each other as the values of the labour employed in their production. But if commodities are to each other as the quantities, they must also be to each other as the  values of the producing labour; for the contrary would necessarily imply, that the two commodities A and B might be equal in value, although the value of the labour employed in one was greater or less than the value of the labour employed in the other; or that A and B might be unequal in value, if the labour employed in each was equal in value. But this difference in the value of two commodities, which were produced by labour of equal value, would be inconsistent with the acknowledged equality of profits, which Mr. Ricardo maintains in common with other writers *.
It is probable, therefore, that this was not Mr. Ricardo's meaning, but that he unconsciously confounded this proposition with another, and really intended to say, that the value of A at two different periods, No. 1 and 2, was  not proportioned to the value of the labour necessary to its production at each period; that although, for example, the value of the labour were doubled at the latter period, the value of the commodity might not be affected. The proposition expressed more simply is, that the value of a commodity and the value of the labour employed in its production, do not bear to each other a constant ratio; or more simply still, that labour may rise and fall in value without affecting the value of the commodity.
This is obviously a very different proposition from the other, and depends in fact on the falsity of the other, or on the contrary proposition, that the values of two contemporary commodities are to each other as the values of the labour employed in producing them. For as value must be value in something, let us ask, in relation to what object might the value of A at period No. 2 be, as here asserted, the same as its value at period No. 1, although the value of the producing labour were doubled? In re-lation to other commodities. And why? Because the rise in labour would be the same in all commodities; but if the values of commodities are to each other as the values of the labour employed in producing them, and if the labour employed in all commodities rose in equal proportion, there could not possibly be any disturbance of the relations existing between all commodities before the rise, and of course A would be of the same value at period No. 2 as at period No. 1.
The only alteration in this instance would be, an alteration in the relation of value between labour and commodities. It would be a simple case of a rise in labour, and (proceeding on the assumption that commodities are determined in value solely by the quantity of labour) the whole amount of the proposition is this, that the values of commodities in relation to each other are not disturbed by an alteration in their values in relation to labour; which is only a particular application of the more general pro-position, that when one commodity or thing alters its value in relation to other commodities, the mutual relations of these other commodities, caeteris paribus, are not thereby affected *.
The reader will notice, that in supposing that while the value of the producing labour was doubled, the commodity remained the same, I have used the expression, the value of the commodity might not be affected, for this reason, that whether it was or was not affected, would depend on the nature of the cause by which the value of the labour was doubled. In the proposition, the values of A and B are to each other as the values of their producing labour, the value of labour means aggregate value. Now the aggregate value of the labour necessary for the production of a commodity may be increased in two ways, either by an augmentation of the quantity of the labour at  the same rate, or by a rise in the rate, that is in the value of a definite portion of it, while the quantity remains the same. It is only in the latter event (which is the one I have supposed to take place) that the value of the commodity would in general continue the same in relation to other commodities, for the precise reason already assigned, that all commodities would be affected in equal proportions. It would be a positive not a comparative rise in the value of the producing labour of the commodity in question; while on the other hand, should the increase in the value have arisen from an augmentation in the quantity of labour, such increase would be probably, although not necessarily comparative.
As the misconception on the part of Mr. Ricardo here noticed is a fundamental one, I make no apology for presenting the reader with a further attempt to show it. The confusion in the proposition will be more apparent by a little alteration in the language.
The value of a commodity A, or the quan-tity of any other commodity B, for which it will exchange, depends on the comparative quantities of labour necessary for the production of A and B. So far there is no obscurity, and the position can be construed only in one sense. When Mr. Ricardo, however, adds, and not on the greater or less compensation which is paid for that labour, everyone must be sensible of a confusion of ideas. In the former clause he is telling us on what circumstance the mutual value of A and B depends, or, in other words, what circumstance determines the quantities in which these two commodities are exchanged for each other; in the latter clause it was evidently his business, as it was his design, to tell us on what the mutual value of A and B did not depend; or, in other words, what circumstance did not determine the quantities in which these commodities are exchanged for each other. Now the only circumstance assigned is obviously the compensation paid for the labour, and the proposition really asserted in this latter clause is, that the mutual value  of A and B does not depend on the compensation paid for the producing labour of A being equal to, or greater, or less than the compensation paid for the producing labour of B : so that this compensation might be equal in the two cases, while the quantities in which A and B were exchanged for each other were unequal.
As far, however, as any thing can be gathered from the confusion of thought and language in Mr. Ricardo's opening section, this is not what he intended to assert. In the first clause he was comparing A and B, and asserting the cause which determined the relation between them; but dropping B by the way, in this latter clause he is speaking of A alone. By quantity of labour in the first clause, he meant quantity of labour necessary to produce A, compared with the quantity of labour necessary to produce B; but by compensation of labour in the latter clause, he does not intend the compensation of labour in A compared to the compensation of labour in B, but the compensation paid for the labour required to produce A at  one time, compared with the compensation paid for the producing labour of A at another time. Hence Mr. Ricardo's sentence is a completely false antithesis.
The author of the Templars' Dialogues on Political Economy seems to have followed Mr. Ricardo in confounding the two distinct propositions above pointed out. This appears the more extraordinary, since he has laid down the first proposition (which I have supposed Mr. Ricardo did not clearly perceive to be involved in the terms employed) in such bold and unmeasured language, as almost to preclude the possibility of its being mistaken either by himself or his readers for any other.
After telling us, that Mr. Ricardo's doctrine is, that A and B are to each other in value as the quantity of labour is which produces A to the quantity which produces B, he says, I assert in the most peremptory manner, that he who says, 'the value of A is to the value of B, as the quantity of labour producing A 18 to the quantity of labour producing B,' does of  necessity deny by implication, that the relations of value between A and B are governed by the value of the labour which severally produces them. Again, so far are the two formulae from presenting merely two different expressions of the same law, that the very best way of expressing negatively Mr. Ricardo's law (viz. A is to B in value as the quantities of the producing labour) would be to say, A is not to B in value as the values of the producing labour *."
Let us examine the reasoning employed to support this extraordinary assertion. It is too long to be introduced here, but it amounts to this, that when the producing labour is increased in quantity, the commodity produced is increased in value; but when the producing labour is increased in value, the value of the commodity produced remains unaltered; and therefore the values of commodities are not to each other as the values of the producing la-bour. For instance, if A and B were each produced by six days' labour, they would be equal in value; but if A should from some cause or other require 12 days' labour, then the value of A would be to the value of B as 12 to 6. But suppose that A in 1810 required six days' labour at 4s., making 24s., and in 1811, 6 days at 6s., making 36s., if the value of the commodity was 40s. at the former period, it would still be 40s. at the latter. And suppose that B in 18 10 required 3 days' labour at 4s., making 12s., and in 1811, 3 days' labour at 6s., making 18s., the value of the commodity at each period would be 20s.
Now this author's argument is, that because A and B at these two periods do not vary in value with the varying value of labour, therefore they are not to each other in value as the values of the producing labour. But it is evident that 40s.) the value of A in 1810, is to 20s., the value of 13 at the same period, as 24s., the value of the producing labour in A, is to 12s., the value of  the labour in B; and again in 1811, 40s. is to 20s., the values of the commodities, as 36s. to 18s., the values of the labour.
The author appears to me to have vacillated unconsciously between two essentially distinct propositions. He has begun (not an uncommon case) by proposing one as the object of his attack, and ended by contending with the other.
This will be seen at a glance when they are placed together.
1. A and B are to each other in value as the values of the producing labour.
2. The value of A at one period is to the value of the producing labour, as the value of A at another period is to the value of the producing labour; or, to conform the expression of it to the preceding instance, the value of A in 1810, 40s., is to the value of the labour at that period, 24s., as the value of A in 1811, 40s., to the value of the producing labour in the same year, 36s., which is manifestly ab-surd; but I lie under a great mistake, if it is not really the proposition which X Y Z * has been attacking, while he supposed himself to be in logical combat with the first.
It is difficult to imagine how an error of this kind (if I am right in supposing it to be one) should have escaped a mind evidently well versed in the detection of ambiguities in argumentation. It appears to have arisen, as in the case of Mr. Ricardo, from blending the comparison of contemporary commodities with that of the same commodity at different periods, which led them to the erroneous inference, that because the value of A at one period did not bear the same relation to the value of its producing labour as at another period, therefore the values of two contemporary commodities did not bear the same relation to each other as the values of the labour respectively bestowed on their production.
 In this chapter I beg not to be understood as contending, either that the values of commodities are to each other as the quantities of labour necessary for their production, or that the values of commodities are to each other as the values of the labour: all that I intend to insist upon is, that if the former is true, the latter cannot be false; and I have endeavoured to explain the source of the misconception which has regarded the two propositions as incompatible and contradictory*. The fact is, that the quantity of labour and the value of labour are in the same case. Any alteration in the comparative quantities of labour required to produce A and B, would alter their value in relation to each other; and an alteration in their mutual value would equally follow from any change in the comparative values of the producing labour,  while the comparative quantities of labour remained the same.
Again, an alteration in the positive quantities of the producing labour in A and B, which left the comparative quantities the same, would not affect the mutual value of these two commodities, any more than an alteration in the positive values of the producing labour, while the same ratio subsisted between those values as before.