From Pope St. John Paul II’s encyclical Fides et Ratio (1984):
I wish to repeat clearly that the study of philosophy is fundamental and indispensable to the structure of theological studies and to the formation of candidates for the priesthood. It is not by chance that the curriculum of theological studies is preceded by a time of special study of philosophy. This decision, confirmed by the Fifth Lateran Council,87 is rooted in the experience which matured through the Middle Ages, when the importance of a constructive harmony of philosophical and theological learning emerged. This ordering of studies influenced, promoted and enabled much of the development of modern philosophy, albeit indirectly. One telling example of this is the influence of the Disputationes Metaphysicæ of Francisco Suárez, which found its way even into the Lutheran universities of Germany. Conversely, the dismantling of this arrangement has created serious gaps in both priestly formation and theological research. Consider, for instance, the disregard of modern thought and culture which has led either to a refusal of any kind of dialogue or to an indiscriminate acceptance of any kind of philosophy.
I trust most sincerely that these difficulties will be overcome by an intelligent philosophical and theological formation, which must never be lacking in the Church.
For the reasons suggested here, it has seemed to me urgent to re-emphasize with this Encyclical Letter the Church’s intense interest in philosophy—indeed the intimate bond which ties theological work to the philosophical search for truth. From this comes the Magisterium’s duty to discern and promote philosophical thinking which is not at odds with faith. It is my task to state principles and criteria which in my judgement are necessary in order to restore a harmonious and creative relationship between theology and philosophy. In the light of these principles and criteria, it will be possible to discern with greater clarity what link, if any, theology should forge with the different philosophical opinions or systems which the world of today presents.
87 Cf. Fifth Lateran Ecumenical Council, Bull Apostolici Regimini Sollicitudo, Session VIII: Conciliorum Œcumenicorum Decreta, 1991, 605-606.
— Fides et Ratio 62-63