Saint Thomas Aquinas, O.P. (Thomas of Aquin or Aquino) was an Italian priest of the Roman Catholic Church in the Dominican Order, and an immensely influential philosopher and theologian in the tradition of scholasticism, known as Doctor Angelicus and Doctor Communis. He is frequently referred to as Thomas because Aquinas refers to his residence rather than his surname. He was the foremost classical proponent of natural theology, and the father of the Thomistic school of philosophy and theology. His influence on Western thought is considerable, and much of modern philosophy was conceived as a reaction against, or as an agreement with, his ideas, particularly in the areas of ethics, natural law and political theory.