" I have already quoted in Marx's own words the passages relative to the subject. The line of argument divides itself clearly into three steps.
First step. Since in exchange two goods are made equal to one another, there must be a common element of similar quantity in the two, and in this common element must reside the principle of Exchange value.
Second step. This common element cannot be the Use value, for in the exchange of goods the use value is disregarded.
Third step. If the use value of commodities be disregarded there remains in them only one common property—that of being products of labour. Consequently, so runs the conclusion, Labour is the principle of value; or, as Marx says, the use value, or "good," only has a value because human labour is made objective in it, is materialised in it.
I have seldom read anything to equal this for bad reasoning and carelessness in drawing conclusions.
The first step may pass, but the second step can only be maintained by a logical fallacy of the grossest kind. The use value cannot be the common element because it is "obviously disregarded in the exchange relations of commodities, for"—I quote literally—"within the exchange relations one use value counts for just as much as any other, if only it is to be had in the proper proportion." What would Marx have said to the following argument?
In an opera company there are three celebrated singers—a tenor, a bass, and a baritone—and these have each a salary of £1000. The question is asked, What is the common circumstance on account of which their salaries are made equal? And I answer, In the question of salary one good voice counts for just as much as any other—a good tenor for as much as a good bass or a good baritone—provided only it is to be had in proper proportion; consequently in the question of salary the good voice is evidently disregarded, and the good voice cannot be the cause of the good salary.
The fallaciousness of this argument is clear. But it is just as clear that Marx's conclusion, from which this is exactly copied, is not a whit more correct. Both commit the same fallacy. They confuse the disregarding of a genus with the disregarding of the specific forms in which this genus manifests itself. In our illustration the circumstance which is of no account as regards the question of salary is evidently only the special form which the good voice assumes, whether tenor, bass, or baritone. It is by no means the good voice in general. And just so is it with the exchange relations of commodities. The special forms under which use value may appear, whether the use be for food, clothing, shelter, or any other thing, is of course disregarded; but the use value of the commodity in general is never disregarded. Marx might have seen that we do not absolutely disregard use value from the fact that there can be no exchange value where there is not a use value—a fact which Marx himself is repeatedly forced to admit."