On the other hand,a commodity is an exchange-value in so far as a definite amount of labour-time has been expended on its production and it accordingly represents materialised labour-time .Yet the commodity as it comes into being is only materialised individual labour-time of a specific kind,and not universal labour-time.The commodity is thus not immediately exchange-value,but has still to become exchange-value.To begin with,it can be materialisation of universal labour-time only when it represents a particular useful application of labour-time,that is a use-value.This is the material condition under which alone the labour-time contained in commodities is regarded as universal,social labour-time.A commodity can only therefore become a use-value if it is realised as an exchange-value,while it can only be realised as an exchange-value if it is alienated and functions as a use-value.The alienation of a commodity as a use-value is only possible to the person for whom it is a use-value,i.e.,an object satisfying particular needs.On the other hand,it can only be alienated in exchange for another commodity,or if we regard the matter from the standpoint of the owner of the other commodity,he too can only alienate,i.e.,realise,his commodity by bringing it into contact with the particular need of which it is the object.During the universal alienation of commodities as use-values they are brought into relation with one another as discrete things which are physically different and because of their specific properties satisfy particular needs.But as mere use-values they exist independently of one another or rather without any connection.They can be exchanged as use-values only in connection with particular needs.They are,however,exchangeable only as equivalents,and they are equivalents only as equal quantities of materialised labour-time,when their physical properties as use-values,and hence the relations of these commodities to specific needs,are entirely disregarded.A commodity functions as an exchange-value if it can freely take the place of a definite quantity of any other commodity,irrespective of whether or not it constitutes a use-value for the owner of the other commodity.But for the owner of the other commodity it becomes a commodity only in so far as it constitutes a use-value for him,and for the owner in whose hands it is it becomes an exchange-value only in so far as it is a commodity for the other owner.
One and the same relation must therefore be simultaneously a relation of essentially equal commodities which differ only in magnitude,i.e.,a relation which expresses their equality as materialisations of universal labour-time,and at the same time it must be their relation as qualitatively different things,as distinct use-values for distinct needs,in short a relation which differentiates them as actual use-values But equality and inequality thus posited are mutually exclusive.The result is not simply a vicious circle of problems,where the solution of one problem presupposes the solution of the other,but a whole complex of contradictory premises,since the fulfillment of one condition depends directly upon the fulfillment of its opposite.
The exchange process must comprise both the evolution and the solution of these contradictions,which cannot however be demonstrated in the process in this simple form We have merely observed how the commodities themselves are related to one another as use-values,i.e.,how commodities as use-values function within the exchange process.On the other hand,exchange-value as we have considered it till now has merely existed as our abstraction,or,if one prefers,as the abstraction of the individual commodity-owner,who keeps the commodity as use-value in the ware-house,and has it on his conscience as exchange-value.In the exchange process,however,the commodities must exist for one another not only as use-values but also as exchange-values,and this aspect of their existence must appear as their own mutual relation.The difficulty which confronted us in the first place was that the commodity as a use-value has to be alienated,disposed of,before it can function as an exchange-value,as materialised labour,while on the contrary its alienation as a use-value presupposes its existence as exchange-value.But let us suppose that this difficulty has been overcome,that the commodity has shed its particular use-value and has thereby fulfilled the material condition of being socially useful labour,instead of the particular labour of an individual by himself.In the exchange process,the commodity as exchange-value must then become a universal equivalent,materialised general labour-time for all other commodities;it has thus no longer the limited function of a particular use-value,but is capable of being directly represented in all use-values as its equivalents.Every commodity however is the commodity which,as a result of the alienation of its particular use-value,must appear as the direct materialisation of universal labour-time.But on the other hand,only particular commodities,particular use-values embodying the labour of private individuals,confront one another in the exchange process.Universal labour-time itself is an abstraction which,as such,does not exist for commodities.
