Galileo > Dialogo di Galileo Galilei
Now referred to as The Dialogue Concerning the Two Chief World Systems, Galileo's watershed work was first published in 1632 with a very long title that indicates the tenseness surrounding its publication. The long title makes sure to announce Galileo's dedicatee, the powerful Duke of Tuscany (Fernando II de Medici, whose name appears bigger than Galileo's on the title page), and suggests that the author will take an even-handed and dispassionate approach to the subject. The frontispiece shows Galileo in conference with Ptolemy and Copernicus. Only Copernicus and Galileo hold scientific instruments.
In this work, Galileo postulated and implicitly advocated the heliocentric (Copernican) world view, contrasting it to the prevailing geocentric (Ptolomeic) model. In order to obtain permission to publish, Galileo promised religious authorities—importantly including his sometime supporter Pope Urban VIII—that he would present heliocentrism as hypothetical, because the view contradicts passages of the Bible that refer to the stillness of the earth and the orbit of the sun. Not convinced that the work did not come out in favor of heliocentrism, after the publication of this work the Roman Inquisition found Galileo “vehemently suspect of heresy” and the book was placed on the Pope's Index of Forbidden Books, where it remained for over 200 years.