History of Western Philosophy (Book Two): Catholic Philosophy is considered a seminal work by the philosopher Bertrand Russell, in which it reviews the influence of the Catholic Church on Western thought during the Middle Ages. This book features a discussion of how the Church dominated political, social, and cultural spheres, leading to the emergence of Catholic philosophy and the emergence of great philosophers such as Augustine and Thomas Aquinas. Russell highlights the intellectual changes that occurred in this era, pointing to the dualisms that characterized Catholic philosophy, such as the relationship between religious and secular authority, as well as the soul and body, and the kingdom of God and the kingdom of this world. The book also examines the influence of these ideas on the development of Western philosophy in the following eras.