I understand Paul C.'s reasoning about why only relative values and prices
can be quantitatively compared. But I'm perplexed that Paul does not think
it is clear that Marx had a different view. In an earlier post, Paul
acknowledged that in the Vol. III, Ch. 9 transformation, MArx was concerned
with the quantitative differences between surplus-value and profit. Now, if
profit is an exchange-value category and surplus-value a value category (i.e.
money and labor-time categories *only*, respectively), talk of quantitative
differences between them--not to speak of an identiy of their aggregate sums--
is pure nonsense. Its like saying 5 apples are more than 3 VCRs--more what?
I do agree that Marx held abstract labor to be the substance of value. But
this does not imply that value is only measurable in terms of that substance.
On p. 148-149 of _Capital_ I, Penguin/Vintage ed., Marx draws an analogy
to sugar and iron: "in order to express the sugar-loaf as a weight [value],
we put it into a relation of weight [value] with the iron [money]. ...
Quantities of iron [money] therefore serve to measure the weight [value] of
the sugar ...." And on p. 188, at the beginning of Ch. 3, we writes "Money
as a measure of value is the necessary form of appearance of the measure of
value which is immanent in commodities, namely labour-time."
Andrew Kliman