Fides et Ratio §52

⁵² 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, or concerning the different forms of idolatry and esoteric superstition found in astrological speculations, without forgetting the more systematic pronouncements against certain claims of Latin Averroism which were incompatible with the Christian faith. 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, fideism and radical traditionalism, for their distrust of reason's natural capacities, and, on the other, rationalism and ontologism 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.