The form taken by value in exchange places value in a category beyond the strict meaning of subjectivity and objectivity. In exchange, value becomes supra-subjective, supra-individual, yet without becoming an objective quality and reality of the things themselves. Value appears as the demand of the object, transcending its immanent reality, to be exchanged and acquired only for another corresponding value. The Ego, even though it is the universal source of values, becomes so far removed from the objects that they can measure their significance by each other without referring in each case to the Ego. But this real relationship between values, which is executed and supported by exchange, evidently has its purpose in eventual subjective enjoyment, that is, in the fact that we receive a greater quantity and intensity of values than would be possible without exchange transactions.
Georg Simmel The Philosophy of Money (1907 [1990]) p.78
