Chapter 1 — Preface to the Roman Catechism
Section 10. For those who intended to corrupt the minds of the faithful, knowing that they could not hold immediate personal intercourse with all, and thus pour into their ears their poisoned doctrines, adopted another plan which enabled them to disseminate error and impiety more easily and extensively. Besides those voluminous works by which they sought the subversion of the Catholic faith - to guard against which (volumes) required perhaps little labour or circumspection, since their contents were clearly heretical - they also composed innumerable smaller books, which, veiling their errors under the semblance of piety, deceived with incredible facility the unsuspecting minds of simple folk.