From Pope St. John Paul II’s encyclical Fides et Ratio (1984):
It is not only in recent times that the Magisterium of the Church has intervened to make its mind known with regard to particular philosophical teachings.* It is enough to recall, by way of example, the pronouncements made through the centuries concerning theories which argued in favour of the pre-existence of the soul,56 or concerning the different forms of idolatry and esoteric superstition found in astrological speculations,57 without forgetting the more systematic pronouncements against certain claims of Latin Averroism which were incompatible with the Christian faith.58
If the Magisterium has spoken out more frequently since the middle of the last century, it is because in that period not a few Catholics felt it their duty to counter various streams of modern thought with a philosophy of their own. At this point, the Magisterium of the Church was obliged to be vigilant lest these philosophies developed in ways which were themselves erroneous and negative. The censures were delivered even-handedly: on the one hand, fideism59 and radical traditionalism,60 for their distrust of reason’s natural capacities, and, on the other, rationalism61 and ontologism62 because they attributed to natural reason a knowledge which only the light of faith could confer. The positive elements of this debate were assembled in the Dogmatic Constitution Dei Filius, in which for the first time an Ecumenical Council—in this case, the First Vatican Council—pronounced solemnly on the relationship between reason and faith. The teaching contained in this document strongly and positively marked the philosophical research of many believers and remains today a standard reference-point for correct and coherent Christian thinking in this regard.
The Magisterium’s pronouncements have been concerned less with individual philosophical theses than with the need for rational and hence ultimately philosophical knowledge for the understanding of faith. In synthesizing and solemnly reaffirming the teachings constantly proposed to the faithful by the ordinary Papal Magisterium, the First Vatican Council showed how inseparable and at the same time how distinct were faith and reason, Revelation and natural knowledge of God. The Council began with the basic criterion, presupposed by Revelation itself, of the natural knowability of the existence of God, the beginning and end of all things,63 and concluded with the solemn assertion quoted earlier: “There are two orders of knowledge, distinct not only in their point of departure, but also in their object”.64 Against all forms of rationalism, then, there was a need to affirm the distinction between the mysteries of faith and the findings of philosophy, and the transcendence and precedence of the mysteries of faith over the findings of philosophy. Against the temptations of fideism, however, it was necessary to stress the unity of truth and thus the positive contribution which rational knowledge can and must make to faith’s knowledge: “Even if faith is superior to reason there can never be a true divergence between faith and reason, since the same God who reveals the mysteries and bestows the gift of faith has also placed in the human spirit the light of reason. This God could not deny himself, nor could the truth ever contradict the truth”.65
56 Cf. Synod of Constantinople, Denzinger, Heinrich, and Adolf Schönmetzer, Enchiridion symbolorum definitionum et declarationum de rebus fidei et morum [DS], 403.
57 Cf. Council of Toledo I, DS 205; Council of Braga I, DS 459-460; Sixtus V, Bull Coeli et Terrae Creator (5 January 1586):Bullarium Romanum 4/4, Rome 1747, 176-179; Urban VIII, Inscrutabilis Iudiciorum (1 April 1631): Bullarium Romanum 6/1, Rome 1758, 268-270.
58 Cf. Ecumenical Council of Vienne, Decree Fidei Catholicae, DS 902; Fifth Lateran Ecumenical Council, Bull Apostoli Regiminis, DS 1440.
59 Cf. Theses a Ludovico Eugenio Bautain iussu sui Episcopi subscriptae (8 September 1840), DS 2751-2756; Theses a Ludovico Eugenio Bautain ex mandato S. Cong. Episcoporum et Religiosorum subscriptae (26 April 1844), DS 2765-2769.
60 Cf. Sacred Congregation of the Index, Decree Theses contra Traditionalismum Augustini Bonnetty (11 June 1855), DS 2811-2814.
61 Cf. Pius IX, Brief Eximiam Tuam (15 June 1857), DS 2828-2831; Brief Gravissimas Inter (11 December 1862), DS 2850-2861.
62 Cf. Sacred Congregation of the Holy Office, Decree Errores Ontologistarum (18 September 1861), DS 2841-2847.
63 Cf. First Vatican Ecumenical Council, Dogmatic Constitution on the Catholic Faith Dei Filius, II: DS 3004; and Canon 2, 1: DS 3026.
64 Ibid., IV: DS 3015, cited in Second Vatican Ecumenical Council, Pastoral Constitution on the Church in the Modern World Gaudium et Spes, 59.
65 First Vatican Ecumenical Council, Dogmatic Constitution on the Catholic Faith Dei Filius, IV: DS 3017.
— Fides et Ratio 52-53
* The confusion that would be engendered and disseminated during Francis’ papacy appears not to have been foreseen by St. JPII. — Ed.