Galileo Galilei

Galileo Galilei (15 February 1564 – 8 January 1642) was an Italian physicist, mathematician, astronomer, and philosopher who played a major role in the Scientific Revolution. His achievements include improvements to the telescope and consequent astronomical observations, and support for Copernicanism. The motion of uniformly accelerated objects, taught in nearly all high school and introductory college physics courses, was studied by Galileo as the subject of kinematics. His contributions to observational astronomy include the telescopic confirmation of the phases of Venus, the discovery of the four largest satellites of Jupiter, named the Galilean moons in his honour, and the observation and analysis of sunspots. Galileo also worked in applied science and technology, improving compass design.

Galileo's championing of Copernicanism (within the pages of Dialogue Concerning the Two Chief World Systems) was controversial within his lifetime. The geocentric view had been dominant since the time of Aristotle, and the controversy engendered by Galileo's presentation of heliocentrism as proven fact resulted in the Catholic Church's prohibiting its advocacy as empirically proven fact, because it was not empirically proven at the time and was contrary to the literal meaning of Scripture. Galileo was eventually forced to recant his heliocentrism and spent the last years of his life under house arrest on orders of the Roman Inquisition.

Galileo Galilei in "But It Does Move"
In 1633 Galileo Galilei was a prisoner in Rome of the Inquisition. He had previously been interrogated by ten different Cardinals when he was approached by Cardinal Sigismondo Gioioso who questioned him using a different approach that he called "an analysis".

Galileo had been quite proud of his Dialogue Concerning the Two Chief World Systems, and had gone out of his way to make sure he had the approval of the Inquisition before publishing it. Unfortunately, Galileo did not present a balanced an examination of the Copernican and Ptolemaic views. His protests to the contrary, Galileo, based on his observations via telescope, concluded that the Copernican view was correct, and made that conclusion plain in the Dialogue. Thus, in 1633, Galileo was summoned to Rome for investigation.

Cardinal Gioioso's approach puzzled Galileo. The Cardinal shared wine and cakes with Galileo before their first meeting, and allowed Galileo to lay on a couch while answering questions. After some brief discussion of the Dialogue, Gioioso questioned Galileo about his mother and his father, and suggested that Galileo resented his father's initial attempts to steer him away from music and mathematics. Galileo denied such anger. He also denied that in his youth he'd wished his father had been removed so as to have the full attention of his mother. At the end of the first session, the Cardinal gave Galileo the choice of continuing their conversations. While Galileo realized that Gioioso was being sincere in giving him the choice, Galileo felt that the Inquisition really left him no choice. At the very minimum, participating in "analysis" with Gioioso would insure that the Inquisition could not inflict harm upon Galileo. Galileo agreed.

The Cardinal's questions brought forth several memories from Galileo's youth. Gioioso explained that this was necessary to get at the heart of Galileo's decisions as an adult, particularly his decision to produce the Dialogue.