The liberty of thinking and publishing whatsoever each one likes, without any hindrances, is not in itself an advantage over which society can wisely rejoice. On the contrary, it is the fountainhead and origin of many evils.
Pope Leo XIIIThe family was ordained of God that children might be trained up for himself; it was before the church, or rather the first form of the church on earth.
Pope Leo XIIIBut the supreme teacher in the Church is the Roman Pontiff. Union of minds, therefore, requires, together with a perfect accord in the one faith, complete submission and obedience of will to the Church and to the Roman Pontiff, as to God Himself.
Pope Leo XIIIIf unbridled licence of speech and writing be granted to all, nothing will remain sacred and inviolate; even the highest and truest mandates of nature, justly held to be the common and noblest heritage of the human race, will not be spared. Thus, truth being gradually obscured by darkness, pernicious and manifold error, as too often happens, will easily prevail.
Pope Leo XIIIWhoso turns his attention to the bitter strifes of these days and seeks a reason for the troubles that vex public and private life must come to the conclusion that a fruitful cause of the evils which now afflict, as well as of those which threaten us, lies in this: that false conclusions concerning divine and human things, which originated in the schools of philosophy, have crept into all the orders of the state, and have been accepted by the common consent of the masses.
Pope Leo XIII