"Certainly the mechanisms of the market offer secure advantages: they help to utilize resources better; they promote the exchange of products; above all they give central place to the person's desires and preferences, which, in a contract, meet the desires and preferences of another person. Nevertheless, these mechanisms carry the risk of an "idolatry" of the market, an idolatry which ignores the existence of goods which by their nature are not and cannot be mere commodities."