The conditions of labor, which creates exchange value, as shown by the analysis of the latter, are social conditions of labor or conditions of social labor. Social, not in the ordinary, but in a special sense. It is a specific form of the social process. The homogeneous simplicity of labor means first of all equality of the labors of various individuals, a reciprocal relation of equality of their labors determined by the actual reduction of all kinds of labor to uniform labor. The labor of every individual, as far as it is expressed in exchange value possesses this social character of equality and finds expression in exchange value only in so far as it is a relation of equality with the labor of all other individuals.
Furthermore, the labor-time of a single individual is directly expressed in exchange value as universal labor-time, and this universal character of individual labor is the manifestation of its social character. The labor-time represented by exchange value is the labor-time of an individual, but of an individual undistinguished from other individuals in so far as they perform the same labor; therefore, the time required by one individual for the production of a certain commodity is the necessary labor-time which any other individual would have to spend on the production of the same commodity. It is the labor-time of an individual, his labor-time, but only as labor-time common to all, regardless as to which particular individual’s labor-time it is. As universal labor-time it is represented in a universal product, in a universal equivalent, in a definite quantity of materialized labor-time: the latter is indifferent as to the particular form of use-value in which it appears directly as the product of an individual, and may be turned at will into any other form of use-value to represent the product of any other individual. Only as such a universal quantity, is it a social quantity. In order to result in exchange value, the labor of an individual must be turned into a universal equivalent, i. e., the labor-time of an individual must be expressed as universal labor-time, or universal labor-time as that