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Books which treat, narrate, or teach lascivious or obscene matters by profession are entirely prohibited, since regard must be had not only for the faith but also for morals, which are easily corrupted by the reading of such books; and those who possess them shall be severely punished by the Bishops.
Ancient books, however, written by heathens, are permitted on account of the elegance and propriety of their language, yet they are by no means to be read by boys.
Books whose principal argument is good, but in which some things are inserted incidentally which pertain to heresy, impiety, divination, or superstition, may be granted once they have been expurgated by Catholic theologians by the authority of the General Inquisition.
The same judgment applies to prologues, summaries, or annotations which have been added by condemned authors to books that are not condemned; but hereafter, they shall not be printed unless corrected.
All books and writings of Geomancy, Hydromancy, Aeromancy, Pyromancy, Onomancy, Chiromancy, and Necromancy, or those in which are contained sorceries, poisoning, auguries, auspices, and incantations of the magical art, are utterly rejected.
Bishops shall diligently provide that books, treatises, and indexes of judicial Astrology be neither read nor held, which dare to affirm as a certainty that anything will come to pass concerning future contingencies, successes, fortuitous events, or those actions which depend upon human will.
However, judgments and natural observations which have been written for the sake of aiding navigation, agriculture, or the medical art are permitted.
In the printing of books or other writings, that which was established in the Lateran Council under Leo X, session 10, shall be observed.
Therefore, if some book is to be printed in the Alma Urbe Rome, it must first be examined by the Vicar of the Supreme Pontiff and the Master of the Sacred Palace, or by a person deputed by Our Most Holy Lord.
In other places, however, the approval and examination shall pertain to the Bishop or another having knowledge of the book or writing to be printed, to be deputed by the same Bishop, and to the Inquisitor of heretical depravity of the City or Diocese in which the printing will take place; and it shall be approved by their hand, to be affixed by their own signature freely and without delay, under the penalties and censures contained in the same decree; with this law and condition added, that an authentic copy of the book to be printed, signed by the author's hand, remain with the Examiner.
The deputed Fathers judged that those who publish manuscript booklets, unless they have first been examined and approved, ought to be subject to the same penalties as printers; and those who have possessed and read them, unless they produce the authors, shall be held as the authors.
The approval of such books itself shall be given in writing, and shall appear authentically on the front of the book, either written or printed; and the approval, examination, and the rest shall be done freely.
Furthermore, in individual Cities and Dioceses, houses or places where the printing art is exercised and libraries of books for sale shall be visited frequently by persons deputed for this purpose by the Bishop or his Vicar, and also by the Inquisitor of heretical depravity, so that nothing of those things which are prohibited is either printed, sold, or possessed.
All Booksellers and whosoever are sellers of books shall have in their libraries an Index of books for sale which they possess, with the signature of the said persons; nor shall they possess or sell or in any way hand over other books without the license of the same deputies, under pain of loss of the books and other penalties to be imposed at the discretion of the Bishops or Inquisitors. Buyers, Readers, or Printers shall be punished at the discretion of the same.
But if anyone introduces any books whatsoever into any City, they shall be bound to declare them to the same deputed persons; or if a public place has been established for merchandise of this kind, the public ministers of that place shall signify to the aforesaid persons that the books have been brought in.
No one shall dare to hand over for reading to anyone, or in any way alienate or lend, a book which he or another has introduced into a City, unless the book has first been shown and license obtained from the deputed persons, or unless it is notoriously known that the book is already permitted to all.
The same shall also be observed by heirs and executors of last wills, so that they may offer the books left by the deceased, or an index of them, to those deputed persons, and obtain license from them before they use them or transfer them to other persons in any way.
In all and each of these cases, a penalty shall be set, either of loss of the books or another, at the discretion of the same Bishops or Inquisitors, according to the quality of the contumacy or offense.
Regarding books which the deputed Fathers have either examined, or expurgated, or handed over to be expurgated, or granted under certain conditions so that they might be printed again, whatever it is established that they have determined, both booksellers and others shall observe.
Nevertheless, it shall be free for Bishops or General Inquisitors, according to the faculty they possess, to prohibit even those books which seem to be permitted by these Rules, if they judge this to be expedient in their Kingdoms or Provinces or Dioceses.
Furthermore, the Secretary of the same deputies shall hand over the names of those books which have been purged by the deputed Fathers, as well as those to whom they have given this province, described by the Notary of the sacred universal Roman Inquisition, by the order of our Most Holy Lord.
Finally, it is commanded to all the faithful that no one dare to read or possess any books contrary to the prescription of these Rules or the prohibition of this Index.