>Alternatively, if one *restricts* the field to commodities, i.e. products
>of labor, as a pre-condition, then one need not talk about exchange at all
>to conclude that all bundles have in common the fact of being products of
>labor. The conclusion was assumed already.
Only the conclusion you state is thereby assumed. It is not Marx's
conclusion. Marx's whole point is the correction of the classical labor
theory of value, viz. the idea that labor was the cause of the value of
commodities. To return to Blake: "they {Smith and Ricardo] did not know
that labor produces two values, one a use value that is antecedent to the
product becoming a commodity and which does enter into a commodity
relations, or into value itself, which is the labor time socially required
in production and which we recognize only as it appears in exchange. If
there were no social contradiction, that is, if goods were produced by
labor in direct social relations, there could no such two fold character of
labor. The reason for this twofold character is social, the division of
classes, and the realization of value by exchange, that is, the recognition
of the value of one commodity by way of another. THE CRITICS OF THE LABOR
THEORY OF VALUE ATTACK THE SMITH-RICARDO HYPOTHESIS WHICH HAS LITTLE IN
COMMON WITH THE MARXIST. Marx neither holds (as nearly everyone believes)
that labor creates all wealth, nor that labor creates all value. Only
*abstract labor creates all value*, and then only for a definite social
reason." (capitalisation mine)
Rakesh