The Catholic Church’s Index Librorum Prohibitorum banned the Protestant Reformation first and many later classics of European culture after it. The first Index, published in 1559, barred every book by Luther, Calvin and the other reformers. Catholics who owned or read a listed book faced excommunication.
The Vatican offices behind it ran from 1559 until 1966. Hubert Wolf, a priest and historian at Münster University, said no other institution had tried to control books for over 400 years.
What the first list banned
Bibles came next. Translating scripture into everyday languages was a Protestant habit, so the Index banned every Bible except the Latin Vulgate. The Talmud and the Koran were banned too.
A second list named books to be purged rather than banned. Plato, Aristotle, Homer, Virgil and Euclid were among the classical authors on it, for reflecting pagan belief. A book could land on the list merely for being printed in a Protestant city. The Index planned purged editions of about 300 books and finished about 50, Wolf said.
How a book got on
After that start, the Vatican worked only on books someone denounced to it. The Congregation of the Index, founded in 1571, met three or four times a year. Two consultors reported on each book, the cardinals debated, and the pope approved the decision.
The public heard which books were banned but never why. The Vatican opened the files to outside researchers in 1998.
The case of Kant
On June 11, 1827, the Index added Immanuel Kant’s Critique of Pure Reason. Kant had died in 1804 and was not a Catholic. Even scholars then needed permission from a bishop or superior to read it.
Writing in Commonweal after research in the Vatican archives, a scholar of the case found the process shallow. The censor, the Camaldolese abbot Alberto Bellenghi, could not read German. He worked from a flawed 1820 Italian translation and copied the prejudices of a hostile 1803 introduction by Francesco Soave.
The committee’s report dismissed Kant’s thought as dark and incomprehensible, fit only for sowing doubt about every kind of truth. Kant never doubted that God exists. He argued that reason alone could not prove it.
