Centesimus Annus §40

⁴⁰ It is the task of the State to provide for the defence and preservation of common goods such as the natural and human environments, which cannot be safeguarded simply by market forces. Just as in the time of primitive capitalism the State had the duty of defending the basic rights of workers, so now, with the new capitalism, the State and all of society have the duty of defending those collective goods which, among others, constitute the essential framework for the legitimate pursuit of personal goals on the part of each individual. Here we find a new limit on the market: there are collective and qualitative needs which cannot be satisfied by market mechanisms. There are important human needs which escape its logic. There are goods which by their very nature cannot and must not be bought or sold. 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.