PAGE Section I.—Commentary. 1. The Index 1 2. The Power of the Church 4 3. Book Prohibitions Antedating the Roman Index 7 4. The Roman Index 11 5. Books Forbidden by General or Particular Decrees 13 6. Duties Imposed by Law and by Nature 18 7. Who Puts Books on the Index? 24 8. The Method of Examination 28 9. The Spirit of the Index Congregation 33 10. Further Explanations 35 a. Why an Author is not Permitted to Defend His Book 35 b. The Index does not Advertise Bad Books 37 c. Index Decisions not Omitted for Fear of Apostasies 39 d. The “Good Catholic” 41 e. A Mortal Sin 43 f. The Galileo Case 44 g. Non-Catholic Book-Laws 46 h. Some Examples of Submission to the Index 48 Section II.—A Summary of the Index. 1. Our Duties in Relation to Forbidden Books 51 2. Forbidden Books 53 a. Books Forbidden by General Decrees 54 b. Books Forbidden by Particular Decrees 57 SECTION I COMMENTARY 1. The Index. In 1901, a reviewer of the Roman Index of Forbidden Books opened his criticism by congratulating himself upon having before him a genuine copy of that book, of which, he says, only a very limited number were printed for the exclusive use of “the leaders of the Church.” Owing to its scarcity, he thinks, the owner of the volume, which he had borrowed, must have paid at least two hundred dollars for it. He could have bought a brand new copy for $2.25. The Index of which he speaks, issued by order of Leo XIII, in 1900, is for sale in this country by B. Herder, St. Louis, Mo. So are the three later editions (1901, 1904, 1907), the last two issued under, and by order of, our gloriously reigning Pontiff, Pius X. When the critic felt his heart beat with joy upon being allowed to view with his own blessed eyes a book so rare, so expensive, and so jealously guarded by “the leaders of the Church,” a whole edition of that same book had already been sold, and a second was about to be put on the market. Its title is now: