13 In the next place, in order that the union of hearts between their chief Pastor and the whole Catholic flock may daily be strengthened, We here call upon you, venerable brothers, with particular earnestness, and strongly urge you to kindle, with priestly zeal and pastoral care, the fire of the love of religion among the faithful entrusted to you, that their attachment to this chair of truth and justice may become closer and firmer, that they may welcome all its teachings with thorough assent of mind and will, wholly rejecting such opinion, even when most widely received, as they know to be contrary to the Church's doctrine. In this matter, the Roman Pontiffs, Our predecessors, and the last of all, Pius IX, of sacred memory, especially in the General Council of the Vatican, have not neglected, so often as there was need, to condemn widespreading errors and to smite them with the apostolic condemnation. This they did, keeping before their eyes the words of St. Paul: "Beware lest any man cheat you by philosophy and vain deceit, according to the tradition of men, according to the elements of the world and not according to Christ."(7) All such censures, We, following in the steps of Our predecessors, do confirm and renew from this apostolic seat of truth, whilst We earnestly ask of the Father of lights(8) that all the faithful, brought to thorough agreement in the like feeling and the same belief, may think and speak even as Ourselves. It is your duty, venerable brothers, sedulously to strive that the seed of heavenly doctrine be sown broadcast in the field of God, and that the teachings of the Catholic faith may be implanted early in the souls of the faithful, may strike deep root in them, and be kept free from the ruinous blight of error. The more the enemies of religion exert themselves to offer the uninformed, especially the young, such instruction as darkens the mind and corrupts morals, the more actively should we endeavor that not only a suitable and solid method of education may flourish but above all that this education be wholly in harmony with the Catholic faith in its literature and system of training, and chiefly in philosophy, upon which the direction of other sciences in great measure depends.(9) Philosophy seeks not the overthrow of divine revelation, but delights rather to prepare its way, and defend it against assailants, both by example and in written works, as the great Augustine and the Angelic Doctor, with all other teachers of Christian wisdom, have proved to Us.
Source: Inscrutabili Dei Consilio (Vatican.va)