The encyclical Fides et Ratio is a continually inspiring document in which John Paul II sought to answer the question of the relationship between faith and reason, and thus between theology and philosophy. It follows the tradition of the Church, but at the same time reflects the post-Conciliar view of the autonomy of the empirical sciences and the humanities. The present study deals with philosophy which John Paul II calls “Christian philosophy.” The concept of metaphysics, which has influenced Christian philosophy, is crucial here. Despite a lot of criticism concerning metaphysics since the modern period, John Paul II defends the metaphysical position as an integral part of the Christian philosopher’s thinking. His understanding of metaphysics will be discussed in the following study.