In no system is everything so singular as to preclude even the hint of exchange. And in no system /…/ is everything a commodity and exchangeable for everything else within a unitary sphere of exchange. Such a construction of the world – in the first case as totally heterogenous in terms of valuation and, in the second, as totally homogenous – would be humanly and culturally impossible. But they are two extremes between which every real economy occupies its own peculiar place.
/…/
The counterdrive to this potential onrush of commodization is culture. /…/
In every society, there are things that are publicly precluded from being commoditized. Some of the prohibitions are cultural and upheld collectively.
/…/
Although the singular and the commodity are opposites, no thing ever quite reaches the ultimate commodity end of the continuum between them. There are no perfect commodities. On the other hand, the exchange function of every economy apears to have a built-in force that drives the exchange system toward the greatest degree of commoditization that the exchange technology permits. The counterforces are culture and the individual, with their drive to discriminate, classify, compare, and sacralize. This means a two-front battle for culture as for the individual – one against commoditization as a homogenizer of exchange values, the other against the utter singularization of things as they are in nature.
Excerpt from Igor Kopytoff (1984), “The cultural biography of things: commodization as process”.