(a) If a book is forbidden, one may not read even the harmless parts of it, for there is the danger that, if one part is read, the other parts will also be read. But, if the part that occasioned the prohibition be removed, the prohibition ceases as regards the remainder of the book.
(b) If a work is forbidden, one may not read any volume, if all the volumes deal with the same subject. But, if the volumes treat of different subjects or of one subject that is divisible (e.g., universal history), one may read such volumes as do not contain the danger that occasioned the prohibition.
(c) If all the works of an author are condemned, the prohibition is understood to apply only to books (i.e., not to smaller works), and only to books dealing with religion, unless it appears that the other kinds of writings are also included; but the prohibition is to be presumed to include works that appear after the condemnation, unless the contrary is manifest.
861. Some outstanding works that have been condemned are the following: (a) In English: _Decline and Fall of The Roman Empire_ (Gibbons); _Myth, Ritual, and Religion_ (Andrew Lang); _History of England_ (Goldsmith); _The Roman Popes_ (Ranke); _The Life and Pontificate of Leo X_ (Roscoe); _Constitutional History of England_ (Hallam); _Political Economy_ (Mill); _Happiness in Hell_ (Mivart); _History of English Literature_ (Taine); _Reign of Charles V_ (Robertson); _Zoonomia_, or The Laws of Organic Life (Darwin).
(b) In French: _Notre Dame de Paris_ (Hugo); _Life of Jesus_ and eighteen other works of Renan; all the works of Anatole France; _The Social Contract_ and four works of Rousseau; nearly all the works of Voltaire; _The Gospel and the Church, Gospel Studies, The Fourth Gospel, Apropos of a Little Book, The Religion of Israel_ (Loisy); all the works of Jean Paul Sartre; _La Deuxieme Sexe_ and _Les Mandarins_ by Simone de Beauvoir.
862. What is meant by “use” of forbidden writings? (a) In the first place, those “use” a writing who read it—that is, who go over it with their eyes, understanding the meaning therein contained. Hence, a person does not violate the church law against forbidden books if he merely listens to another read; although he might sin against the natural law, and even against the church law, if he induced the other to read to him; neither does a person violate the church law, if he merely glances at the characters, without understanding the sense expressed. Example: Titus, a professor of theology, has permission to read forbidden books, and he sometimes reads to his class doctrinal passages from works on the Index in order to explain and refute errors. Balbus examines very carefully the pages of a beautifully printed copy of a forbidden work, but he understands hardly a word of it, since it is in a foreign language. Neither Titus’ class nor Balbus are guilty of reading as forbidden by the Church, for strict interpretation is given to penal laws (see 485).
(b) In the second place, those “use” a forbidden writing who retain it—that is, who keep it in their home as belonging to themselves or borrowed from another, or who give it for safekeeping to another, even though they are not able to read it. Hence, a librarian who has forbidden books on his shelves does not break the law, since the books are not his property, nor are they kept in his home. A bookbinder also who receives forbidden books is considered as excused through _epieikeia_ for the time the books are in his shop, especially if his customer has the permission to read those books. Example: Sempronius bought an expensive work and then discovered that it is on the Index. Is he obliged to destroy it? No, if he does not wish to destroy it, he may, if he does not delay beyond a month, either give it to someone who has permission to keep it, or obtain that permission for himself.
(c) In the third place, those “use” a forbidden writing who communicate it to others—for example, those who make presents of works that are on the Index, who lend such books to others, or place them where others will read them, who read to others passages or write out excerpts for them. It is lawful, however, for professors in theological and other classes of sacred science to read from forbidden works to their student body, if a suitable explanation and refutation exclude all danger.
(d) Lastly, those fall under the law as violators who co-operate in the production or distribution of forbidden literature—for example, publishers, owners, authors, translators, booksellers, printers, etc. (cfr. 976 sqq., on cooperation in Worship).
863. The church law on forbidden literature affects all Catholics not excepted by law, no matter how learned they may be, what position they may hold, or how immune from danger they may seem, unless they obtain permission to read such literature from the Holy See, the Ordinary, or their regular Superior (Canon 1402). Those excepted by law and who do not need to seek such permission are certain prelates and students. (a) Cardinals, Bishops, and other Ordinaries (Canon 1401), and likewise major superiors in exempt clerical orders (Canon 198, Sec. 1) are not bound by the church prohibition of books dangerous to faith; (b) those who are pursuing theological or biblical studies may use forbidden editions of scripture, provided these are correct and complete as to the text, and contain no attacks on Catholic teaching in the introductions and annotations (Canon 1400). This permission extends not only to seminarians, but also to lay students; not only to those who are at school, but also to those who are really studying outside of school, such as professors, writers and those who are preparing lectures or dissertations.