Index of Prohibited Books

INDEX OF PROHIBITED BOOKS. — The expression “prohibited books” designates books whose reading is forbidden to the faithful by positive ecclesiastical law, whether general or particular, or by a decree issued by the competent authority, ordinarily the S. Congregation of the S. Office or the Ordinary of the place.

The faithful, however, must refrain from reading not only books proscribed by law or decree, but every writing that exposes them to the danger of losing the faith or corrupting morals. This is a moral obligation imposed by natural law, which admits neither exemption nor dispensation. The seriousness of this obligation is proportionate to the danger to which the soul is exposed.

But since ordinary members of the faithful would rarely be able to perceive the danger to which they are exposing themselves, it is natural that the Church, through suitable warnings and prohibitions, should keep them away from bad reading.

The I. dei l. p. (Index librorum prohibitorum) is the catalogue of books that the Holy See has prohibited as bad or dangerous to the integrity of faith and morals, and which the faithful, without special permission, may neither read nor keep. The Church has always fulfilled her duty of vigilance over books, but until the invention of printing she did not feel the need

to compile a catalogue of prohibited books, because writings considered dangerous were burned.

The Council of Nicaea (325) prohibited the book Thalia by Arius; Pope Anastasius condemned the works of Origen, because they were more harmful to the ignorant than useful to the learned; s. Leo the Great rejected in Rome the writings of the Manichaeans and enjoined the Spanish bishops to rise up against the books of the Priscillianists. From the earliest centuries the question of the pagan classics (v.) was debated. The danger increased with the spread of printed books, and the Church’s intervention then

became more frequent. At first censorship (v.) Imprimatur (v.), having been preceded in this by the civil authorities, such as Henry VIII in England and Charles V in the Netherlands, and by the Sorbonne in France.

But despite this, numerous heretical books were published, and Paul III, in order to contain the danger, entrusted the proscription of books infected with heresy to the cardinal inquisitors general. Paul IV was the first to order them, in 1557, to compile an I. (or catalogue) of l. p., which was published in 1559. It comprised three lists: of authors, of book titles,

(courtesy of Prof. E. Josi)