Publisher: Against the Current
Date Written: 01/07/2014
Year Published: 2014
Resource Type: Article
Cx Number: CX20784
In celebration of the 450th anniversary of Galileo's birth, this article examines the famous scientist's life, contributions, and relevance today.
Publication of The Starry Messenger brought Galileo instant fame. But along with his great celebrity came a barrage of criticisms, from both secular and religious sources.
Secular critics, upset by the inherent rejection of Aristotelian astronomy, questioned the efficacy of the telescope in revealing the nature of viewed objects without distortion. They also found Galileo's explanations incomplete, since he didn't explain how unattached heavenly bodies could fail to fall onto the earth and why the earth's rotation does not result in vicious winds that would create havoc on earth.
Galileo had no doubt that the objects and phenomena he observed through the telescope had a consistency that was not compatible with hypothetical distortions produced by the telescope. He was also convinced that his hypothesis of untethered planets and stars was correct, and there would ultimately be a viable explanation for why they do not fall to earth. The lack of winds due to the rotation and motion of the earth was explained by Galileo (see below) by understanding sufficiently well what we now call the principle of inertia.
The religious criticisms centered on his adoption of the Copernican hypothesis of a heliocentric universe, a view counter to the doctrines of the Catholic Church.(8)
Physics was Galileo's life-long intellectual preoccupation that predated his interest in astronomy. Today, astronomy is a subfield of physics. This was not the case in Galileo's time when the Aristotelian distinction between corruptible (terrestrial) and incorruptible (heavenly) matter held sway.
Paradoxically, astronomy was always a subject rooted in detailed measurements, while physics was based on qualitative principles that were not tested in quantitative detail. Perhaps Galileo's most important contribution to physics was to make measurement a central aspect of the practice of physics.