This year Nicholaus Copernicus published De revolutionibus orbium coelestium (Cohen, I. 24). The old physics of Aristotle and the astronomy of Ptolemy were countered by Copernicus. ... This book, usually called the Little Commentary, set out Copernicus's theory of a universe with the sun at its center. ... Ptolemy used a number of devices to solve many of the discrepancies in Aristotle's astronomy while still staying true to Aristotle's natural philosophy. ... This proved that the heavens can change unlike Aristotle's beliefs that the heavens were incorruptible. ...

• Word Count: 1448
• Approx Pages: 6

The answer to his questions was: 'I think therefore I am'. ... Aristotle was the first to devise a plausible theory of the universe. ... He did this through combining his cosmology and astronomy with Aristotle's physics. ... In 1543 a priest named Copernicus published a book called 'De Revolutionibus Orbium Coelestium". In this book he discussed his heliocentric theory which argued that the Sun is the centre of the universe and does not move just like the stars. ...

• Word Count: 1993
• Approx Pages: 8
• Has Bibliography

In the letter he wrote: "I hold that the Sun is located at the centre of the revolutions of the heavenly orbs and does not change place, and that the Earth rotates on itself and moves around it. ... I confirm this view not only by refuting Ptolemy's and Aristotle's arguments, but also by producing many for the other side, especially some pertaining to physical effects whose causes perhaps cannot be determined in any other way, and other astronomical discoveries; these discoveries clearly confute the Ptolemaic system, and they agree admirably with this other position and confirm it."...

• Word Count: 1769
• Approx Pages: 7
• Has Bibliography

Both Aristotle and the Catholic Church approved of this truth, and at the time, it was extremely blasphemous to question either voice. ... However, even after Galileo had apologized for the contents of his "heretical" book, the Catholic Church still kept extremely close tabs on him, and proceeded to do so until the day of his death. ... Before leaving to face the Holy Office of the Inquisition in Rome, Galileo wrote a letter to a friend of his in which he stated, "I hear from well-informed parties that the Jesuit Fathers have insinuated in the highest quarters that my book is more execrable an...

• Word Count: 1974
• Approx Pages: 8
• Has Bibliography
• Grade Level: Undergraduate