>But for Marx, the characterisation of exchange as an equivalence relation
depends on positing money, or at >least a "universal equivalent". In Chapter
1 this is discussed under the section "C. The general form of value" >where
Marx at first posits linen in the role of general equivalent.
>As he puts it (p71), "The value of every commodity is now, by being
equated to linen, not only differentiated >from its own use-value, but from
all other use vlues generally, and is, by that very fact, expressed as that
which >is common to all commodities. By this form, commodities are, for the
first time, effectively brought into >relation with one another as values,
or made to appear as exchange-values".
>That is, only by the existence of a universal equivalent is exchange
constituted as an equivalence relation.
>And later (p73), "Finally, the form C gives to the world of commodities a
general social relative form of value, >because, and in so far as, thereby
all commodities, with the exception of one, are excluded from the
>equivalent form. A single commodity, the linen, appears therefore to have
acquired the character of direct >exchangeability with every other commodity
because, and in so far as, this character is denied to eery other
>commodity." Marx continues in a footnote, "It is by no means self-evident
that this character of direct and >universal exchangeability is, so to
speak, a polar one, and as intimately connected with its opposite pole, the
>absence of direct exchangeability, as the positive pole of the magnet is
with its negative counterpart. It may t>herefore be imagined that all
commodities can simultaneously have this character impressed upon them,
>just as it can be imagined that all Catholics can be popes together. It is
of course highly desirable for the petit >bourgeois, for whom the production
of commodities is the nec plus ultra of human freedom and individual
>independence, that the inconvieniences resulting from this character of
commodities not being directly >exchangeable, should be removed. "
>Later, in the section, "3. Transition from the General form of value to the
Money-form" he states that it is only >when the General form of value
becomes restricted to a particular commodity, money, that "the general form
>of relative value of the world of commodities obtains real consistence and
general social validity".