In a substantial finale to a series of posts (1218-1220 plus 1234), 
Mike offers a schematic of the connection between Marx's value 
theory and his historical materialist analysis of capitalist exploitation, in 
particular as this relates to the role of the capitalist mode of 
production in the latter.
Before responding to this, I should make clear what I believe to be 
at issue.  I do not deny, although I remain a bit skeptical, that there might 
be very good reasons to couch Marx's analysis of capitalist exploitation 
in value-theoretic terms--e.g., to maintain terminological continuity with 
his labor-based notion of exploitation.  What I have criticized are certain 
specific claims as to "necessary" connections between value-theoretic 
postulates and the analysis of exploitation.  
But here, in light of "Gil and Mike's surprising agreement" (about 
which more below), much of this criticism need not concern us.  That 
is: my *primary* critique of Marx's value-theoretic account of 
capitalist exploitation is that it is based on the invalidly derived 
conclusion to Ch. 5, to the effect that surplus value must be 
explained on the basis of price-value equivalence.  Quite plainly 
this conclusion does not follow from the arguments presented by Marx 
in the body of the chapter.  But Mike and I agree on this.  
[Mike considers our agreement on this point "surprising".  To the 
contrary, I'm surprised that more listmates have not 
accepted this point.  I mean, an invalid argument is an invalid argument, 
no matter what you think about Marx's method, the value of money, 
or the connection between total prices and total values.]
I'm willing to believe that a valid argument might be constructed, as 
Mike puts it, 
>to  bridge from the understanding of capital as M-C-M' to the
> buying and selling of labour-power as the premise of
> capitalist relations of production
, but I know that the *necessity* of purchase and 
subsumption of labor power under capital as the basis for modern 
capitalist exploitation cannot be established on the sole basis of 
value-theoretic categories, because as Mike's earlier posts ably 
demonstrated, the basis of this necessity is rooted in historically 
contingent strategic terms which are essentially independent of 
Marx's value theory.  
This point informs my response to Mike's latest post.  
Here Mike makes two arguments concerning the connection between 
Marx's value theory and his account of capitalist exploitation, and 
nominally, his focus on the role of the purchase and subsumption of 
labor power in that account.
The first argument is that labor, *understood as the unique use-value 
of labor power*, is the necessary basis of capital.  But it's better 
here to let Mike speak for himself:
>      Let's go back to the Grundrisse. It was there that
> Marx, who had long understood that the central relationship
> in capitalism was that of capitalist and wage-labourer (cf.,
> eg, 1844 Mss., Wage-Labour and Capital), grasped that you
> could not move (logically) from labour to capital but
> needed--- if one was to grasp the nature of capital--- to
> proceed from money to capital. Where, then, did wage-labour
> come in? The question Marx asked in the Grundrisse is---
> what is the use-value for capital which stands outside
> capital as such? He answered (Vintage/Penguin, 272), "The
> only *use-value*, therefore, which can form the opposite
> pole to capital is *labour (to be exact, value-creating,
> productive labour*." He underlines his (dialectical) point
> two pages later: "the real *not-capital* is *labour*.
>      It is obvious here from the outset that the subject
> Marx has in mind is capital-as-a-whole, since the opposite
> pole to any *individual* capital can be *another* individual
> capital (as it is indeed at the level of many capitals).
> There is no need to reveal this by pointing out that the
> capitalist class cannot defraud itself, and there is no
> place at all here for questions of equivalent or non-
> equivalent exchanges. Rather, the question is what is not-
> capital, what is the opposite to the objectified labour (in
> money and commodities) of which capital is a specific unity?
>      Marx's point was the same when he began to plan the
> extension of his Contribution to the Critique of Political
> Economy. You can see this in the Collected Works, Vol. 29
> (p. 503), when he says: "*Labour is* the only *use value
> which can present an opposite and a complement to money as
> capital*, and it exists in labour capacity, which exists as
> a subject." And, he continues: "The exchange through which
> money becomes capital cannot be its exchange with
> commodities [in general] but can only be one with its
> conceptually determined opposite, the commodity which is
> itself a conceptually determined opposite of it--- labour."
> (504). (I restrained myself from adding italics to
> "conceptually determined".)
>      Marx returned to the same point in his 1861-3 Mss in
> his discussion of the transformation of money into capital,
> where he notes, "The sole antithesis to objectified labour
> is non-objectified, *living labour*." (Vol. 30, p.35) He
> goes on to note that the only commodity which "has any
> direct use value at all for the value which is to be
> valorised" is one whose "use itself constitutes the creation
> of value" and "such use value is only possessed by *living
> labour capacity*" (36).
>      As can be seen, Marx is very clearly arguing here in
> value-theoretic terms.
That's true, but it's not enough to establish the essential 
connection between capitalist exploitation and the purchase and 
subsumption of wage labor.  Here's why:  as a general matter,
**it is not necessary to purchase and subsume the commodity
labor power in order to enjoy the use value of labor power.**
Two counter-examples explicitly affirmed by Marx:  usurer's capital 
did not purchase or subsume the commodity labor power, and yet it 
managed to "swallow up everything in excess of the producer's most essential 
means of subsistence", thus constituting "capital's mode of 
exploitation without its mode of production." [III, 732, Penguin]
Second: proto-industrial merchant's capital also gained the use value 
of labor power, but it didn't subsume labor power.  Marx again: "A 
further example is *merchant's capital*, which commissions a number 
of immediate producers, then collects their produce and sells it, 
perhaps making them advances in the form of raw materials, etc, or 
even money...Here too we find no formal subsumption of labor under 
capital." [I, 1023] 
Of course, the subsumption of wage labour becomes central to the 
process of capitalist exploitation given the historical 
pre-conditions of the capitalist mode of production (primarily the 
emergence of a class "free in the double sense"), but the reasons for 
this, quite ably spelled out by Mike (and initiated by Marx in Ch. 23 
of Volume III), are historically contingent strategic ones, not value 
theoretic ones.  
So, granting everything Mike said in the preceding passage, no 
value-theoretic basis for focusing on the purchase and subsumption of 
labor power on capital has been established.  That means, putting 
aside invalid arguments, there are no value-theoretic grounds for 
Marx's exclusive Volume I focus on the purchase and subsumption of 
labor power as the basis for capitalist exploitation.  
Thus, from the standpoint of valid theoretical arguments in Volume 
I, the purchase and subsumption of labor power is no less 
"incidental" to the process of capitalist exploitation than are 
price-value disparities (in combination with "something...in the 
background which is not visible in the circulation itself", i.e. 
production of new value).  More on this in a second.
Now, time out for an aside before turning to Mike's second argument.
This has to do a seeming disparity in Mike's and my 
perception of where "the problem" is in Marx's argument of Volume I, 
part 2.  Mike writes:
> The logical question (once the
> concept of capital is developed) which drives [Marx's] enquiry
> is-- what can be a use-value for capital, self-valorising
> value, when it enters into an exchange? The only trace you
> can find of this, however, in Ch. 5 and Ch. 6 is Marx's
> statement at the beginning of Ch. 6 that capital "must be
> lucky enough" to find on the market "a commodity whose use-
> value possesses the peculiar property of being a source of
> value, whose actual consumption is therefore an
> objectification of labour, hence a creation of value"
> (Vintage,270). That's it! No discussion of how labour-power
> is necessary for capital to exist as such (as opposed to as
> money), no consideration of labour as "the conceptually
> determined opposite" of capital, no stress upon living,
> subjective labour vs. objectified labour.
>      In its place, we get the exercise of Ch. 5 (which
> surfaces in the 1861-3 Mss as an exploration of whether
> capital as such is compatible with the nature of money,
> commodity and circulation) and Ch. 6's dropping from the sky
> of both the existence of the doubly-free producer (as a
> "historical presupposition") and *also* the situation of
> that doubly-free producer as seller of labour-power
> (presumably *another* historical presupposition--- since
> nothing here has explained why that producer does not rent
> means of production).
>      I've always felt that Gil's ammunition was misdirected,
> and that his real target should be the leap Marx makes in
> Ch. 6 to the buying and selling of labour-power because this
> step is not developed logically in CAPITAL. 
Well, Mike, I think this is a case of you say to-MAY-to, I say 
to-MAH-to.  Marx concludes Ch. 5, invalidly as we agree, that surplus 
value must be based on the stipulation of price-value equivalence.  
On the very next page, beginning Ch. 6, Marx reasserts this 
stipulation **and uses it to motivate his subsequent focus on that 
particular commodity, labor power**.  That is, if one accepts this 
stipulation, then Marx is perfectly legitimate in taking the fact of 
a working class "free in the double sense" as a theoretical given--it 
does exist, after all.  **If**, however, one discards the stipulation 
of price-value equivalence, then Marx's procedure in Ch. 6 **is** 
utterly arbitrary, as you suggest.
Now, to Mike's second argument:
>      Finally (for now), come back to how/why Marx proceeded
> from money as capital to the sale of labour-power (and thus
> capitalist relations of production). Fred and I have argued
> Marx makes this transition because "societies in which the
> capitalist mode of production prevails" was the subject from
> the outset. In the 1861-3 Mss, Marx explicitly offers
> another point after having decribed living labour as the
> sole antithesis to objectified labour:
> 
> "Let us therefore assume that the money-owner buys labour,
> hence the seller sells not a commodity but labour. This
> relation cannot be explained on the basis of the relation of
> the circulation of commodities, considered previously, where
> the only parties confronting each other are the owners of
> commodities. For the moment we shall not inquire here into
> the conditions for this relation, and simply assume it as a
> fact." (Vol. 30,35)
> 
> And, he then proceeds to follow the familar argument in
> Ch.6. In short, Marx *assumed as a fact* the sale of labour-
> power (presumably because it was the characteristic relation
> in capitalism). The logical development isn't there in the
> Mss, and it isn't there in CAPITAL. Gil thinks it needs to
> be--- because he doesn't accept that the subject of CAPITAL
> is societies in which the capitalist mode of production
> prevails; 
That's not exactly true.  I'm willing to accept this given for 
Volumes I and II of Capital, anyway.  However, granting that Marx
took the sale [and subsumption] of labor power "as a fact" cannot 
justify its centrality in Marx's theoretical account of capitalist 
exploitation.  Marx also took price-value disparities "as a fact" 
about modern capitalism, for example, and yet he dismisses such disparities 
as "accidental" while crowning the purchase and subsumption of labor 
power as *central* to the logic of modern capitalist exploitation.
But--and this is the bottom line--there is no legitimate 
value-theoretic basis whatsoever for this differential treatment, 
even including the passages from the Grundrisse that Mike cites 
above.
To put it another way, Mike has established two things in this post.  
First:  capitalist exploitation as Marx defines it requires the 
production of new value (the use value of labor power).  True, and I 
have not suggested otherwise.  However, this does not of itself imply 
the necessity of subsuming wage labor under capital, as demonstrated 
both by Marx's historical analysis and Roemer's theoretical analysis.
Second:  Marx assumes what must be proven, that the purchase and 
subsumption of labor power is central to capitalist exploitation given 
the existence of a working class "free in the double sense."  Yes, he does 
indeed assume this, but also yes, it must still be proven.
In solidarity, Gil