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Neo-scholasticism and neo-Thomism are terms used to describe the 19th- and 20th-century revival of Thomistic and scholastic thought within the Roman Catholic Church. In response to the growing philosophical movement known as modernism, the Roman Catholic Church encouraged a rejuvenation of scholastic thought. Scholasticism, particularly the work of Thomas Aquinas, came to be viewed as the ultimate response to modernism and the appropriate philosophical position of the Roman Catholic Church.
Papal support for neo-scholasticism and neo-Thomism was explicitly given in Aeterni Patris. In this encyclical, Pope Leo XIII urged the Catholic Church to promote the philosophical teachings of St. Thomas and return to the philosophical framework of scholasticism. After describing Aquinas’s work in glowing terms, Pope Leo XIII urged the church to “restore the golden wisdom of St. Thomas, and to spread it far and wide for the defense and beauty of the Catholic faith, for the good of society, and for the advantage of all the sciences. . . . Let carefully selected teachers endeavor to implant the doctrine of Thomas Aquinas in the minds of students, and set forth clearly his solidity and excellence over others” (Encyclical of Pope Leo XIII, On the Restoration of Christian Philosophy, Aeterni Patris, August 4, 1879).
Neo-scholasticism is a general term that covers the revival of the teachings of multiple early church and medieval theologians; neo-Thomism, on the other hand, narrows the focus to the work of Thomas Aquinas. Neo-scholasticism as a whole seeks to apply scholastic philosophical frameworks, chiefly those developed by Aquinas, to modern issues. Proponents of this movement explain that it is not merely a slavish adherence to the intellectual ideas of the past, but a dynamic effort to adapt and expand those ideas for the modern world.
One Roman Catholic philosopher, writes, “Thomism is not simply a museum piece; it is a living and developing movement of thought, deriving its inspiration from Aquinas but conducting its meditation on his writings in the light of subsequent philosophy and of subsequent cultural developments in general” (Copleston, F., Aquinas, Penguin Books, 1991, pp. 258–259).
In summary, neo-Thomism or neo-scholasticism is a movement to reestablish Thomistic and scholastic thought within the Roman Catholic Church. Developed as a response to modernism and spurred on by several popes, most notably Pope Leo XIII, proponents of neo-Thomism strive to return Roman Catholic philosophy to the framework and principles of Thomas Aquinas. It continues to be a popular way to address reason and theology in Roman Catholicism, and, as a movement, continues to influence Roman Catholic philosophy today.