Thomism is the philosophical school that arose as a legacy of the work and thought of Thomas Aquinas. The word comes from the name of its originator, whose Summa Theologica is arguably second only to the Bible in importance to the Catholic Church. In the Encyclical Doctoris Angelici, Pius X cautioned that the teachings of the Catholic Church cannot be understood scientifically without the basic philosophical underpinnings of Aquinas's major theses.
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