Galileo

From EvoWiki

Galileo Galilei (1564-1642) was a physicist and astronomer who got in serious trouble for some of his conclusions, making him a martyr figure. His work includes:

• A pendulum's oscillation period is independent of oscillation amplitude, to lowest order
• Objects with different masses fall with the same acceleration, in the absence of friction
• Invention of several mechanical devices.
• Development of a telescope in 1609.
• Discovery of the Moon's mountains, Venus's phases, Jupiter's satellites, the Sun's spots, and large numbers of stars.
• Advocacy of heliocentrism.

According to him some years later, early in his career, Galileo once noticed that both small and large hailstones start falling at around the same time. He wondered if Aristotle was really right about heavier objects falling faster than lighter ones in proportion to their weight, and he started his experiments on falling objects. He found that Aristotle was dead wrong, and as his career continued ,he ended up finding that Aristotle was in error about other subjects. This did not please some of his academic colleagues; some of them considered Aristotle's work almost as inspired as the Bible, calling him ille philosophus ("The Philosopher").

Galileo had a prickly personality. He did not suffer fools gladly, or at least those he considered fools. He often made sarcastic remarks about his critics:

• He commented that a critic who recently died would get to see Jupiter's moons on the way to Heaven.
• When someone claimed that Jupiter's moons were telescope artifacts, he offered a big reward for constructing a device that makes such artifacts only around Jupiter.
• When someone claimed that the Moon is covered with some transparent substance that gives it a flat and non-mountainous surface, he responded by claiming that that substance could just as well form mountains ten times as large as those he observed.

About religion, Galileo considered himself a good Catholic; he even consulted with theologians on how to make heliocentrism theologically acceptable. But they seemed reluctant to accept it, though they were OK with it being described as a speculative hypothesis without any special claim to truth, as Osiander had described Copernicus's work, and as philosophers had often described controversial theories in previous centuries.

He attribted to Cardinal Baronius the comment "that the intention of the Holy Ghost is to teach us how one goes to heaven. not how heaven goes" (Letter to the Grand Duchess Christina of Tuscany, 1615), and he expounded on theological matters in a similar vein. This was an early version of Stephen Jay Gould's Non-Overlapping Magisteria (NOMA), but some theologians back then may not have been pleased about sacrificing some territory. Heliocentrism was contrary to the literal statements of the Bible, as well as to what most scientists/philosophers had taught. They may also have been displeased about him quoting Copernicus about how Church Father Lactantius had ignorantly ridiculed the roundness of the Earth.

Some of the enemies he made were in the Church, and he was ordered to stop presenting heliocentrism as fact. But he was assured by Pope Urban VIII that he could present heliocentrism as a speculative hypothesis. So in 1632, he published his Dialogue Concerning the Two Chief World Systems, following the letter, but not the spirit, of that decree. The geocentrist was made to look silly, and the Pope concluded that it was a swipe against him.

The Church proscribed heliocentrism, and he was induced to recant it. And though the Church had some good scientists in its ranks, notably among the Jesuits, they became good soldiers and rejected not only heliocentrism but also a willingness to commit to new theories about the heavens.