Source: Simon Clarke (1980), The Value of Value, Capital and Class, 10.
“The more radical interpretation of the concept of value gave it more than a strictly economic significance. Marx’s concept of value expresses not merely the material foundation of capitalist exploitation but also, and inseperably, its social form. Within Marxist economics this implies that value is not simply a technical coefficient, it implies that the process of production, appropriation and circulation of value is a social process in which quantitative magnitudes are socially determined, in the course of struggles between and within classes . Thus the sum of value expressed in a particular commodity cannot be identified with the quantity of labour embodied in it, for the concept of value refers to the socially necessary labour time embodied, to abstract rather than to concrete labour, and this quantity can only be established when private labours are socially validated through the circulation of commodities and of capital . Thus the concept of value can only be considered in relation to the entire circuit of capital, and cannot be considered in relation to production alone.
Moreover neither the quantity of labour embodied in the commodity, nor the quantity of socially necessary labout time attributed to it can be considered as technical coefficients. The social form within which labour is expended plays a major role in determining both the quantity of labour that is expended in producing a commodity with a given technology, and the relation of this quantity to the socially necessary labour time through the social validation of labour time. Finally, the technology itself cannot be treated as an exogenous variable, for the pace and pattern of technological development is also conditioned by the social form of production . Thus consideration of the social form of labour cannot be treated as a sociological study that supplements the hard rigour of the economist, it is inseparable from consideration of the most fundamental economic and even technological features of capitalism.”
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“If we consider the production and circulation of use-values the two spheres can be defined independently of one another: a certain determinate quantity of use-values is first produced and then exchanged one for another. However as soon as we consider the production and circulation of value, which is the basis for our understanding of the social form of production, it becomes impossible to consider production and circulation independently of one another. Labour time is expended in production, but this labour time is only socially validated in circulation, so value cannot exist prior to exchange, while surplus value depends on the relation between the result of two exchanges (of money capital for labour power and of commodity capital for money) . Thus value cannot be determined within production, independently of the social validation of the labour expended within circulation: circulation is the social form within which apparently independent productive activities are brought into relation with one another and have the stamp of value imposed on them. However value cannot be determined in circulation either, for circulation is the form in which the social mediation of private labours takes place and the latter provide the material foundation of the social determination of value. Thus to isolate production from circulation, even analytically, is to isolate independent productive activities from one another, and so to deprive production of its social form. To isolate circulation from production, on the other hand, is to isolate the social relations between producers from their material foundation. It is in this sense that production and circulation can only be seen as moments of a whole, as the development of the contradictory unity of value and use-value with which Capital begins. The argument holds with added force when we turn to surplus value, and so capital, which depends in addition on the commodity form of labour power.
The idea that the circuit of capital is a totality of which production and circulation are moments is not a metaphysical idea, although Marx does say that the commodity appears to be ‘a very queer thing, abounding in metaphysical subtleties and theological niceties’ (Capital, I, p. 71, 1967 Moscow edition). The totality is not simply a conceptual totality, an Hegelian idea imposed on reality, it is real and it has a concrete existence. Its reality is that of the class relation between labour and capital, and its existence is the everyday experience of millions of dispossessed workers.”