Intro to Humanity & Nature

Science is the method through which we encounter the third "other" with which we can compare and contrast humanity: nature.  Dr. Bencivenga is providing an introduction into the modern conception of science.  This interpretation will be coming from the sciences itself.  Specifically, we will be looking at Galileo and Heisenberg.  

Galileo is regarded as the founder of modern science, including the scientific method.  Dr. Bencivenga will introduce this method and critique it, as well.  We will also be looking at a dialogue between two important theories about the universe.  These two views are coming from Ptolemy and Copernicus.

When encountering nature, some of the most basic phenomena that we observe are the sun, moon, stars and planets.  Each night and each year, we see shifting patterns in these phenomena.  The sun moves in the same direction all the time, but sometimes it appears as if the stars move in an opposite direction.  The earth, however, seems to remain still.  Based on this most basic data, then, it was commonly thought that the earth was the center of the universe.

Three Ancient Views: Aristotle thought that the entire universe was spherical.  Indeed, he thought that it was a series of concentric spheres.  The innermost sphere was made of the four basic elements: earth, water, wind, and fire.  This allows for things to live, die and change. Beyond the moon, everything is made of ether, an unchanging substance. Ptolemy explained the motions of heavenly bodies by appealing to eccentrics and epicycles.  Eccentricity means that the earth is not exactly at the center of the universe.  An epicycle is a circle that is centered on the perimeter of another circle.  He hypothesized that planets and stars did not merely travel in a circular pattern, but that they traveled in a circle around the perimeter of another circle.  Copernicus, in contrast to these other two views, thought that the sun (rather than the earth) is the center of the universe.

The Players: Gallileo's dialogue includes three figures, but the author himself never directly speaks.  Simplicio is named after a commentator of Aristotle and he represents the Aristotelian/Ptolemic view.  Salviati is the spokesman for Gallileo and Copernicus.  Sagredo is a neutral and intelligent observer, but we also see that he ends up sympathizing with Salviati and he straightens the Copernican view.  The dialogue takes place over four days.  The first day is about Aristotelian physics.  The second is about the daily rotation of the earth around the sun.  The third is about the yearly rotation around the sun and the fourth is about the tides.

Practical Rhetoric: Dr. Bencivenga notes that the dialogue is meant to be somewhat leisurely and playful, so as to allow for transgressions.  He also reminds us of the danger of addressing such issues at the time.  It was considered heresy to claim that the earth revolved around the sun.  Indeed, one could be executed for such crimes.  Galileo himself was tried in 1616 and was forced to recant his views.  The dialogue is thus an attempt to distance himself from his own claims.  He distances himself from the views he represents in order to try to avoid persecution.  His attempt was unsuccessful, however.  It took two years for The Church to grant permission to publish the book, which was then revoked.  Galileo was then tried and shown the instruments of torture, after which he recanted his views again and was then sentenced as a heretic.