Some men, as the Apostle of the Gentiles warns us, are "ever learning yet never attaining knowledge of the truth." They contend that the human mind can discover no truth that is certain or sure; they reject the truths revealed by God and necessary for our eternal salvation. Such men have strayed pathetically far from the teaching of Christ and the views expressed by the Apostle when he said, "Let us all attain to the unity of the faith and of the deep knowledge of the son of God...that we may no longer be children, tossed to and fro and carried about by every wind of doctrine devised in the wickedness of men, in craftiness, according to the wiles of error. Anyone who consciously and wantonly attacks known truth, who arms himself with falsehood in his speech, his writings, or his conduct in order to attract and win over less learned men and to shape the inexperienced and impressionable minds of the young to his own way of thinking, takes advantage of the inexperience and innocence of others and engages in an altogether despicable business. In this connection we must urge to careful, exact, and prudent presentation of the truth those especially who, through the books, magazines, and daily newspapers which are so abundant today, have such a great effect on the instruction and development of the minds of men, and especially of the young, and play such a large part in forming their opinions and shaping their characters. These people have a serious duty to disseminate, not lies, error, and obscenity, but only the truth; they are particularly bound to publicize what is conducive to good and virtuous conduct, not to vice. (Papal Encyclical, Ad Petri Cathedram, 29 June 1959).