What is the social doctrine of the Church?
The expression “the Church’s social teaching” designates the set of orientations of the Catholic Church with respect to social issues. It brings together the pronouncements of the Catholic magisterium on everything that has to do with man’s presence in society and in a social context. It is a reflection developed in the light faith and the ecclesial tradition.
The function of Catholic social doctrine is to proclaim an entire vision of man and humanity and denounce the sin of injustice and violence that moves through society in various ways (cf. Compendium of the Social Doctrine of the Church, No. 81). 
The Church’s social doctrine, therefore, is not an ideology, nor is it to be confused with a political doctrine. It might accord with the various ideologies and political doctrines when these seek the truth and the building of the common good, but it will denounce them whenever they stray from these ideals.
The Church’s social doctrine “is to be found at the crossroads where Christian life and conscience come into contact with the real world. This teaching is seen in the efforts of individuals, families, people involved in cultural and social life, as well as politicians and statesmen to give it a concrete form and application in history” (John Paul II, “Centesimus Annus,” No. 59).
It pursues integral human development, which is “the fulfillment of the whole man and of every man” (Paul VI, “Populorum Progressio,” No. 42; Benedict XVI, “Caritas in Veritate,” No. 8).
Proclaiming the Gospel to society in its political, economic, juridical and cultural dimensions, the Church wishes to actualize Jesus’ message in the course of history and seeks to collaborate in the building of the common good, illuminating social relations with the light of the Gospel. 
The expression “social doctrine” goes back to Pius XI (“Quadragesimo Anno,” 1931) and designates the doctrinal corpus that refers to the society developed in the Church beginning with the encyclical “Rerum Novarum” (1891) of Leo XIII. In 2004, the Pontifical Council for Justice and Peace published the Compendium of the Social Doctrine of the Church, which presents in systematic form the content of the social doctrine of the Church produced up to that time. From that point forward it became the obligatory document to refer to for those who desire to deepen their knowledge of this sector.
“Rerum Novarum,” considered the first major document of the social doctrine of the Church, deals with the worker question at the end of the 19th century. Leo XIII denounced the distressing situation of factory workers, afflicted by misery, in a contest much transformed by the industrial revolution. After “Rerum Novarum,” various encyclicals and various messages touching on social questions appeared.
With its social doctrine, the Church does not wish to impose itself on society, but rather to furnish criteria of discernment for the orientation and formation of consciences. In this regard, Catholic social doctrine has a function of proclaiming an entire vision of man and humanity, and also of denouncing the sin of injustice and violence that moves through society in various ways (Compendium of the Social Doctrine of the Church, No. 81). It does not get into technical details nor does it present itself as a third way to substitute for political and economic systems.
Its purpose is religious, being the object of the field of moral theology. Its goal is to interpret the realities of human existence, examining their conformity to evangelical teaching. It is a doctrine that is especially addressed to every Christian who assumes a role of responsibility in society, helping him to act with justice and charity, that is, it aims at orienting Christian conduct.
Because of this, Catholic social doctrine implies “responsibilities regarding the building, organization and functioning of society, that is to say, political, economic and administrative obligations -- obligations of a secular nature -- which belong to the lay faithful, not to priests or religious” (Compendium of the Social Doctrine of the Church, No. 83).
Human rights, the common good, social life, development, justice, family, work, economy, politics, the international community, the environment, peace. These are all areas upon which the Church reflects in the context of social doctrine.
Every man is a being open to relationships with others in society. To secure his own personal good and the good of his family, every person is called fully to realize himself, promoting the development and good of his society. The person is thus the center of Catholic social teaching. Any content of this teaching has its basis in the dignity of the human person. Other fundamental principles of Catholic social teaching are the common good, subsidiarity and solidarity. 
Dignity of the human person: the Church does not think of the state, the party, or the ethnic group, in the first place. She thinks of the person as a unique and unrepeatable being, created in the image of God. A society is just only if it knows how to respect the dignity of every person. Accordingly, “the social order and its development must invariably work to the benefit of the human person if the disposition of affairs is to be subordinate to the personal realm and not contrariwise” (“Gaudium et Spes,” No. 26).
Respect for human dignity necessarily comes through the fact of considering our neighbor as another “I”, without excluding anyone. The life of the other must be taken into consideration along with the means that are necessary for maintaining it in a dignified way. The content of Catholic social doctrine is therefore universal, because it considers every person’s dignity inalienable, unique and necessary for building the good of all.
Common good: the common good is “the sum of those conditions of social life which allow social groups and their individual members relatively thorough and ready access to their own fulfillment” (“Gaudium et Spes,” No. 26). It is not the simple sum of particular goods of every subject. It is an indivisible good, because only together is it possible to attain it, add to it and conserve it (Compendium of the Social Doctrine of the Church, No. 164).
To put itself authentically at the service of man, society must make its aim the common good, as the good of all men and each man (Catechism of the Catholic Church, No. 1912).
The common good, for example, refers to essential services for human beings: access to food, shelter, work, education, culture, transportation, health, information, freedom. It requires commitment to peace, the organization of state powers, a solid juridical order, protection of the environment.
Subsidiarity: the principle of subsidiarity indicates that in society the institutions and organizations at a higher level must have the attitude of help (“subsidium”) -- and, therefore, of support, promotion and growth -- in relation to those at a lower level (Compendium of the Social Doctrine of the Church, No. 186).
What is meant by “higher level” institutions are those more general institutions (for example, the federal government in relation to regional governments, and the latter in relation to municipal governments) and the state organizations in relation to nongovernmental bodies. It is important to note the principle of subsidiarity inverts the logic of centralized governments and welfare states. For these governments, the state must organize and control social services, and the nongovernmental organizations do nothing else but help in this work. According to the principle of subsidiarity, people, organizing themselves, must seek, in their own history, values and principles, the best solutions to their problems, and the state must help them to implement these solutions in seeking the common good.
The fundamental objective of this principle is to guarantee that the person is the protagonist in his personal and social life. It defends persons from the abuses of higher-level social bodies -- for instance, the state -- and directs that the higher level institutions help individuals and intermediary groups to carry out their proper functions (Compendium of the Social Doctrine of the Church, No. 187).
Subsidiarity does not call for forms of centralization, bureaucratization, welfarism, the unjustified and excessive presence of the state and public apparatus, because it holds that depriving society of responsibility provokes the loss of human energies and the overgrowth of the domain of the state.
On the positive side, the principle of subsidiarity indicates the importance of giving support to persons, families, associations, private initiatives, promoting “appropriate methods for making citizens more responsible in actively ‘being a part’ of the political and social reality of their country” (Compendium of the Social Doctrine of the Church, No. 187).
Solidarity: solidarity is not a mere sentiment of compassion for the evils suffered by many persons near or far. It is the firm and persevering determination to commit ourselves to the good of each and every person, because “we are all really responsible for all” (“Sollicitudo Rei Socialis,” No. 38).
Solidarity presents itself under two complementary aspects: that of social principle -- organization of institutions -- and that of moral virtue -- personal responsibility toward our neighbors (Compendium of the Social Doctrine of the Church, No. 193).
Solidarity manifests itself above all in the distribution of goods and the remuneration of labor. Catholic social teaching defends the fact that socio-economic problems “can be resolved only with the help of all the forms of solidarity: solidarity of the poor among themselves, between rich and poor, of workers among themselves, between employers and employees in a business, solidarity among nations and peoples” (Catechism of the Catholic Church, No. 1941).
The integration of subsidiarity and solidarity: in the application of the Church’s social doctrine, the principles of subsidiarity and solidarity must always be seen and applied together because “the former without the latter gives way to social privatism, while the latter without the former gives way to paternalist social assistance that is demeaning to those in need” (“Caritas in Veritate,” No. 58).
Catholic social teaching has the value of an instrument of evangelization. It proclaims and actualizes the message of Jesus Christ in areas of importance for man’s life. Major themes of the Church's social doctrine are the family, work, economic life, politics, the international community, protection of the environment and promotion of peace. 
Family: the Church considers the family “the first natural society, with underived rights that are proper to it, and places it at the center of social life.”It is “the first and vital cell of society,” the basis of the life of persons and of every social order (Compendium of the Social Doctrine of the Church, No. 211).
The family has its foundation in the free decision of the husband and wife to join themselves in matrimony. It is an environment of life, of the reciprocal giving of the man and the woman and of good for the children. It is a natural community in which human sociality is experienced and “makes a unique and irreplaceable contribution to the good of society” (Compendium of the Social Doctrine of the Church, No. 213).
Work: human work has a double dimension. In an objective sense “it is the sum of activities, resources, instruments and technologies used by men and women to produce things.” In a subjective sense it “the activity of the human person as a dynamic being capable of performing a variety of actions that are part of the work process and that correspond to his personal vocation” (Compendium of the Social Doctrine of the Church, No. 270).
Work is a duty for man but it must never be considered a simple commodity or an impersonal element of productive organization. Work is an essential expression of the person, the person himself being the parameter of the dignity of work (Compendium of the Social Doctrine of the Church, No. 271).
Economy: the object of economy is “the development of wealth and its progressive increase, not only in quantity but also in quality.” All of that “is morally correct if it is directed to man's overall development in solidarity and to that of the society in which people live and work” (Compendium of the Social Doctrine of the Church, No. 334).
Catholic social teaching considers the freedom of the person in economic matters a fundamental value and recognizes the just function of profit, harmonized with the capacity of business to serve society. It defends the free market, recommends that the state operate by the principle of subsidiarity, values the co-presence of public and private action, defends the achievement of an integral and solidary development for humanity.
Politics: The political community is “the organic and organizing unity of a real people.” Its duty is to promote the common good, acting in view of a human environment in which there is offered to citizens “the possibility of truly exercising their human rights and of fulfilling completely their corresponding duties” (Compendium of the Social Doctrine of the Church, Nos. 385, 389).
Catholic social teaching recognizes the value of the democratic system and validity of the principle of the division of powers of a state. It affirms that the political community is constituted to be at the service of civil society. The Church and political community are different by nature, both by configuration and by the goals they propose (Compendium of the Social Doctrine of the Church, No. 424).
The international community: the coexistence of nations “is based on the same values that should guide relations among human beings: truth, justice, active solidarity and freedom.” Such coexistence has law as the guarantee of its order (Compendium of the Social Doctrine of the Church, Nos. 433, 434). International politics must aim at the objective of peace, of development and the struggle against poverty through the adoption of coordinated measures.
The Church’s magisterium defends the institution of “some universal public authority acknowledged as such by all and endowed with effective power to safeguard, on the behalf of all, security, regard for justice, and respect for rights” (Compendium of the Social Doctrine of the Church, No. 441).
Environment: the Catholic Church affirms that taking care of the environment is a challenge for all of humanity. It is a matter of a common and universal duty to respect a good that is collective and destined for all (Compendium of the Social Doctrine of the Church, No. 466).
In the face of grave economic problems, Catholic teaching defends a change of mentality that leads to the adoption of new lifestyles. These lifestyles must be marked by sobriety, temperance, self-discipline on the personal and social level.
Peace: peace is a universal value and duty. It is the fruit of justice, understood in the broad sense of respect for the balance of all of the dimensions of the human person. Peace is also the fruit of love, it is the proper and specific act charity (Compendium of the Social Doctrine of the Church, No. 494). The Church the promotion of peace in the world an integral part of her mission and also calls every citizen to this task.
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For the Church’s social doctrine, the ultimate objective of every social action is integral human development, that is, to permit that the development of all the dimensions of the human person (material, affective, social, spiritual) regards everyone in society. 
In 1967 Pope Paul VI published his encyclical “Populorum Progressio” in which he presented the concept of integral human development. With this, he criticized the idea that the progress of nations could be measured only by their economic growth or only by the growth of the buying power of the population.
Paul VI anticipated in this way critical reflections that in the succeeding decades became common, through ideas such as that of sustainable development, which began to spread beginning with a 1980 document of the International Union for the Conservation of Nature, or indices of human development and development understood as growth in social opportunities, which were seen in the 1990s. In 2009 Pope Benedict XVI took up the concept again, using it as the basis for the composition of his encyclical “Caritas in Veritate.”
Integral human development implies that the possibilities created by growth and economic development of nations be within everyone’s reach. Besides that, it considers that development cannot only be material, but must include all dimensions of the person. Those, for example who have much increased their buying power but who are shut up in an individualistic mentality and do not collaborate in the building of the common good, or who have not grown intellectually or in the spiritual life, has not developed in an integral way.
In a world whose wealth continues to grow but that sees global inequalities and suffers from dehumanization in social relations and in the lifestyles of the populations with the most resources, the concept of integral human development is clearly an instrument for dialogue with every current of social and political thought and for the denunciation of the crisis of meaning and the injustices relevant to society.
The popes have worked without ceasing to shed light on the vast reality of social life and to offer, in the light of the Gospel, directives to illuminate the journey of an authentic human development. 
While the Church’s social doctrine has been characterized by a more structured development since the end of the 19th century, it is the result of ancient experience and pastoral work. “[T]he Church has never failed to show interest in society. Nonetheless, the Encyclical Letter ‘Rerum novarum’ marks the beginning of a new path” (Compendium of the Social Doctrine of the Church, No. 87).
Stages of Catholic social teaching:
-- From 1891 to today the Church’s social doctrine has been a constant teaching of all the popes.
-- Leo XIII (1878-1903), in “Rerum Novarum” (1891), denounced the miserable conditions in which lived the working classes, who were the protagonists of the industrial revolution.
-- Pius XI (1922-1939), in Quadragesimo Anno” (1931), enlarges Christian social doctrine. Faces the difficult issue of totalitarianism, embodied in the fascist, communist, socialist and Nazi regimes.
-- Pius XII (1939-1958), who reigned during and after World War II, focused attention on the “signs of the times.” Although he did not publish a social encyclical, in his numerous speeches there is an enormous variety of political, juridical, social and economic teachings.
-- John XXIII (1958-1963), in “Mater et Magistra” (1961) and in “Pacem in Terris” (1963), he opens Catholic social doctrine “to all men of good will,” and the social question thus becomes a universal topic that is the interest and responsibility of all men and peoples.
-- With the pastoral constitution “Gaudium et Spes” (1965), Vatican II highlights the face of a Church truly solidary with humanity and its history. Already in the declaration “Dignitatis Humanae” (1965), the Council stresses the right of religious liberty.
-- Paul VI (1963-1978), in “Populorum Progressio” (1967) and in “Octogesima Adveniens” (1971), states that development is “the new name for peace.” He created justice and peace commission, which is now known as the Pontifical Council for Justice and Peace.
-- John Paul II (1978-2005) works to spread the Church’s social teaching to all continents. He writes 3 social encyclicals: “Laborem Exercens”(1981), “Sollicitudo Rei Socialis”(1987) and “Centesimus Annus”(1991). Besides this, the Compendium of the Social Doctrine of the Church bears his apostolic signature.
-- Benedict XVI (2005), in his social encyclical “Caritas in Veritate”(2009), defends the integral development of the human person based on charity and truth.
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