In his encyclical Laborem Exercens, Pope John Paul II rejected the idea that "private ownership of the means of production" should remain an "untouchable dogma" of economic life. He also rejects a mere conversion of private property into state property and the creation of a command economy. His vision of an alternative is captured in the following lines:
Merely converting the means of production into State property in the collectivist system is by no means equivalent to "socializing" that property. We can speak of socializing only when the subject character of society is ensured, that is to say, when on the basis of his work each person is fully entitled to consider himself a part-owner of the great workbench at which he is working with every one else… the members of each body would be looked upon and treated as persons and encouraged to take an active part in the life of the body.
There is little said here about markets – in fact, the word "market" does not appear even once throughout the entire encyclical. Thus the "socializing" of the economy is evidently a task that can take place without excessive and ultimately harmful interference in the market. Instead, it can come about through the proliferation of organizations wherein the "subject character of society is ensured," where "each person is fully entitled to consider himself a part-owner" of his place of work, and where the members are "encouraged to take an active part in the life of the body." These are the underlying principles of workers' cooperatives.
One example of the cooperative principle in action is the Mondragón, a cluster of cooperatives in the Basque region of Spain. It can't be mere coincidence that this organization, which is the largest and most successful cooperative in the world, was founded by a Catholic priest by the name of José María Arizmendiarrieta. To me it suggests that there is something in the Catholic view of society and justice that is naturally hospitable to the idea of the workers' cooperative.