In the last several weeks, I have come to know more about Galileo than I do about many of my close friends.  After reading Dava Sobel’s Galileo’s Daughter and attending the convocation on Thursday, I have a good background understanding of both Galileo himself and of 17th century Italy.  Sobel presents Galileo in a different way from typical history books, which usually explain that, as an astronomer and philosopher, Galileo refined the telescope to reveal the heavens.  He shocked the world with startling evidence for Copernicus’ heliocentric model of the universe, and he was accused of being a heretic.  Sobel affirms all of these facts except the final one; in fact, she makes it quite clear that Galileo was a devout Catholic who acquiesced when the church told him to stop spreading his “heretical views.”
         The convocation reasserted many of the key points of Sobel’s book, but from a different angle.  After hearing the thesis of the lecture, I began thinking to myself how elementary I must sound to educated people when I write.  Not only was it eloquent, it completely outlined the main points of the lecture--that Galileo used pictures to verify Copernican cosmology, and that equally powerful pictures have distorted our image of Galileo's character and achievements.
        For a long time, people valued Aristotle’s use of empiricism, which is using logic to prove a theory, instead of scientific evidence.  Ptolemy, also an empiricist, proposed a explanation of the universe in which the earth is the center, and it is surrounded by a rotating sphere containing the sun and the stars.  Sensory perceptions, such as the sun appearing to move across the sky and the feeling of motionlessness, support this geocentric view.  The Catholic Church endorsed geocentricism because it seemed to be in agreement with several passages of the Bible, including Joshua 10:12-14 and Psalms 103:1,5.  Also, as I noted from the lecture, if the earth is not the center of the universe, a possibility arises for multiple worlds.  If multiple worlds exist, then multiple Christs could exist, and this idea is heretical to the Church.  This “reality” held unchallenged for 13-1500 years.  We viewed several ancient drawings illustrating Ptolemy’s geocentricism.  In 1543, mathematician Nicolaus Copernicus published De Revolutionibus.  He had the right idea for the heliocentric universe, but he lacked evidence for his claim.  Galileo provided much evidence for the theory, using drawings of the moon’s roughness as part of his proof for the sun-centered world.  I was particularly interested in hearing about the process by which Galileo and other artists create perspective.  Galileo’s use of this element in his sketches helped make them credible.
         The second part of the lecture focused on how pictures have distorted our impression of Galileo himself.  One portrait showed him with a whimsical smile on his face, which made me think twice about taking this man’s work seriously.  Perhaps the strangest image we viewed was Galileo’s preserved middle finger, displayed in an upright position (see below).  I wonder what he would think of that!  In a way, it is fitting--although he was a humble man, he enjoyed the sport of tearing down the theories that opposed his own.