After this long and cautious introduction, Galileo comes to the matter itself,—the discussion of the principles of exegesis of Scripture with respect to natural science. He employs the same arguments as in his letter to Castelli, only more in detail, and cites several passages from St. Augustine in support of his views, as to how far questions of natural philosophy should be left to the understanding and to science. He also quotes a saying of Cardinal Baronius: “The Holy Spirit intended _to teach us how to go to heaven, and not how the heavens go_.” Galileo then illustrates by examples how derogatory it will be to the dignity of Holy Scripture if every unauthorised scribbler is permitted to adduce passages from it in support of his views, which he often does not interpret rightly; and experience shows the futility of this method of proof. He then turns to the claim of theologians to enforce upon others in scientific discussions opinions which they hold to agree with passages of Scripture, while maintaining that they are not bound to explain the scientific phenomena which are opposed to their decisions. In support of this they affirm that theology is the queen of all the sciences, and need not condescend to accommodate herself to the teachings of other sciences far beneath her: they must submit to her as their sovereign, and modify their conclusions accordingly. This leads Galileo to some considerations which he will here set forth, that he may learn the opinions of others more expert on such questions than he is, and to whose decisions he is always ready to bow. He is in doubt whether some ambiguity has not crept in for want of more precision in defining why theology is entitled to be called a queen. It must either be because all that is taught by other sciences is comprised in and explained by theology, only in a higher sense; or because theology treats of a subject which far surpasses in importance all the subjects of which profane science treats. But even the theologians themselves will hardly maintain that the title belongs to theology in the first sense; for no one can say that geometry, astronomy, music, and medicine, are better treated of in Scripture than in the writings of Archimedes, Ptolemy, Boccius, and Galen. It appears then that the royal prerogative of theology must be derived from some other source. Galileo here remarks:— “If then theology occupies herself solely with the highest problems, maintains her throne by reason of the supreme authority conferred on her, and does not condescend to the lower sciences as not affecting salvation, the professors of theology should not assume authority on subjects which they have not studied. For this is just as if an absolute ruler should demand, without being a physician or an architect, that people should treat themselves, or erect buildings, according to his directions, to the great peril of poor sick people and obvious ruin of the edifices.”