**2. CST: The General Background**

While Catholic reflections on issues of justice and social ethics have long drawn on a scholastic tradition of natural-law reasoning and, more recently, on scriptural themes, CST generally refers to papal and episcopal documents beginning with Leo XIII's encyclical *Rerum Novarum* in 1891. The so-called "social encyclicals" continue to the present, with later popes sometimes using the anniversary dates of the publication of *Rerum Novarum* to issue encyclicals that draw upon, even as they extend, key elements of Leo's analysis. Such celebratory encyclicals include Pius XI's 1931 *Quadragesimo Anno* on the fortieth anniversary of *Rerum Novarum*, Paul VI's 1971 *Octogesima adveniens* on its eightieth anniversary, and John Paul II's 1991 *Centesimus Annus* on its one-hundredth anniversary. In overview, CST reveals both continuity and development, with three aspects especially prominent. First, CST self-consciously brings the Catholic theological tradition to an engagement with the political and socio-economic conditions of modernity that, depending on the historical circumstances at the time of publication, will offer different emphases. Thus, Leo XIII was especially concerned with the rights of workers in an era of largely unfettered capitalism. Forty years later, Pius XI, amidst the rise of communism and fascism, highlighted the dignity of persons in the context of intermediate institutions and voluntary associations with an appeal to the principle of subsidiarity. Paul VI, drawing from the writings of his predecessor, John XXIII, emphasized the global dimensions of human rights claims. John Paul II criticized the inadequacies of both collectivist economic systems and unregulated market approaches, emphasizing the need for both perspectives to offer safeguards to protect the dignity of persons, with particular attention paid to the needs of the poor.

Second, the social encyclicals illustrate the varied theological and philosophical warrants at work in Catholic teaching. Appeals to natural law reasoning, drawing on traditional Thomistic understandings, are significant. At the same time, and increasingly since the papacy of John XXIII, one finds the language of individual rights based on the dignity of persons, including civil, political, and economic rights. Moreover, especially since the papacy of John Paul II (1978–2005) and continuing in the social encyclicals of Pope Benedict XVI (2005–2013) and Pope Francis (2013–), one finds appeals to human solidarity as a central theme, an emphasis that reflects an increasingly global perspective on such issues as poverty, immigration, and environmental devastation.

Third, the range of warrants at work in CST reflects the broad audience for such documents: persons for whom expressly theological and scriptural themes will resonate, as well as others of "good will" for whom natural law and humanistic appeals may prove persuasive. While these different warrants may at times generate tensions, especially in the context of social and religious pluralism, there are ways to view Catholic social teaching as there are ways to view Catholic social teaching as distinctive in its own right while also often intersecting with other perspectives in political and social ethics.
