Publication of Galileo's Dialogue Concerning the Two Chief World Systems

Publication Details. The book, titled Dialogo sopra i due massimi sistemi del mondo, was published in 1632. It was dedicated to Ferdinando II de' Medici, Grand Duke of Tuscany, who received the first printed copy on February 22, 1632. The work was published with formal authorization from the Inquisition and papal permission.

Content and Reception. The Dialogue compares Copernicus's heliocentric system with Ptolemy's geocentric model. The character Simplicio, defending the geocentric view, was often portrayed as making errors, leading to perceptions of the work as a polemic against Aristotelian geocentrism. Pope Urban VIII was initially charmed by the book, having it read aloud to him.

Consequences. Despite initial success, the book alienated Pope Urban VIII and the Jesuits. In 1633, Galileo was found "vehemently suspect of heresy" based on the book, which was placed on the Index of Forbidden Books. It was not removed from the Index until 1835.