# Galileo's Real Enemies

1. Aug 31, 2005

### zoobyshoe

I'm reading the book Galileo's Daughter by Dava Sobel, and discovering from it, one again, that the popular notions that are in the air about historic figures are usually skewed and misleading.

The title of the book comes from the fact this is a biography of Galileo that draws heavily on the letters written to him by one of his daughters. His letters to her were destroyed, but hers to him survived, and much of what he wrote to her can be deduced from her replies and comments.

I'm not even up to the point where she is old enough to start writing to him, and the controversy has already started to brew concerning what his discovery of the moons of Jupiter and the existence of sunspots means about the then view of the universe.

At this point, no one in the Church is the least bit upset. The Pope and many Cardinals like Galileo, and are intrigued by his discoveries. He is respected and approved of.

Except by the followers of Aristotle.

Galileo has been chewing the teaching of Aristotle up and spitting them out, debunked, for many years. He proved that an object does not fall 10 times faster because it is 10 times heavier than another falling object, and he also severely trounced and embarrassed an aristotelian philosopher in a public debate over why ice floats. The Aristotelian's confabulation about this was that ice, while it was heavier than water, couldn't break the water's surface tension because of it's shape: usually having flat surfaces.

Galileo asked why, then, if he forcibly shoved a piece of ice beneath the surface of the water, breaking it's surface tension, and let the ice go, it always floated back to the surface?

"Before answering the adversaries' arguments," a contemporary observer reported of Galileo's debating style, "he amplified and reinforced them with apparently very powerful evidence which then made his adversaries look more ridiculous when he eventually destroyed their positions."

-p.[44]

It was, apparently, his correction of the Aristotelian ideas on purely terrestrial matters, not any of his astronomical discoveries, that so provoked the hate of the embarrassed Aristotelians, that they undertook to blacken his name and reputation with the highest authorities in existence at the time: the church.

"While working on his project [a treatise on floating bodies], he recieved a disturbing letter from an artist acquaintance in Rome: I have been told by a friend of mine, a priest who is very fond of you,' the painter Ludovico Cardi da Cigoli warned Galileo, that a certain crowd of ill-disposed men envious of your virtue and merits met at the house of the archbishop there [in Florence] and put their heads together in a mad quest for any means by which they could damage you, either in regard to the motion of the earth or otherwise. One of them wished to have a preacher state from the pulpit that you were asserting outlandish things. The priest, having percieved the animosity against you, replied as a good Christian and a religious man ought to do. Now I write this to you so that your eyes will be open to such envy and malice on the part of that sort of evildoers.'"

From then on the conspirators worked to gain the ears of anyone with any influence, and turn them against Galileo by highlighting where his discoveries seemed to contradict scripture.

When they eventually found a priest who would denounce him from the puplit, a Cardinal stepped in, censured the priest and made him apologize. The Aristotelians, though, found yet another. One of them also worked on one of Galileo's patrons, with some success.

That's as far as I've gotten in the book, but everyone knows the ending, and it's clear that the Aristotelian conspirators succeed in turning the Catholic Church against Galileo.

I was so surprised to discover that the eventual gagging of Galileo was not instigated by imperious church authorities, as is the conventional notion, but the embarrassed, debunked followers of Aristotle, that I thought it worth a mention.
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The paperback edition I have is published by Penguin books, N.Y. 2000.

2. Aug 31, 2005

### Math Is Hard

Staff Emeritus
So the letters were real? I just assumed it was completely a work of fiction.

3. Aug 31, 2005

### SpaceTiger

Staff Emeritus
Wow, nice summary, thanks zoob. I actually have that book on my shelf, but never got around to reading it.

4. Aug 31, 2005

### hypatia

It does tease me enough to make me want to read it. And we thought it was ruff to show new trends of science today, jeesh!

5. Aug 31, 2005

### Staff: Mentor

Such a thing can be incredibly embarassing, and its not surprising that he earned a lot of enemies with, essentially, his invention of the scientific method. Things that were held as self-evident before him quickly became self-evidently wrong.

Tyco Brahe is said to have dropped fruit at dinner parties to demonstrate that mass has no effect on rate of fall (acceleration). I wonder if such a blunt, brash demonstration of the obviousness of Aristotle's error ever caused someone to jump over the table at him?

Last edited: Aug 31, 2005
6. Aug 31, 2005

### zoobyshoe

Same here, at first. I thought it was "historical fiction". I picked it up on a whim for a quarter at the swap meet a couple weeks ago. Turns out, though, it's pure history, with a strong sidelight on his relationship by letter with his eldest daughter, whom he put into a nunnery when she was a girl. She was illegitimate, like all three of his children, and back then that meant she had no hope of marrying well, so he figured the best thing he could do for her and her sister was get them into a nunnery. This was common practise back then, apparently.

The author, Dava Sobel, translated the letters she used herself. I suspect they have never been translated into English before.

7. Aug 31, 2005

### zoobyshoe

I'm afraid I'm completely bored with the letters from the nunnery parts and am just reading it for the Galileo history, which is all new to me.

I'm now on page 156, and the new Pope, Urban VIII is still a great fan of Galileo, and very much enjoys having his treatises read to him while he eats. He loves Galileo's style.

The Church, stirred up by the Aristotelians, has already issued it's official stand on the notion of a heliocentric universe, which is that it is contrary to scripture, but Galileo has taken this very much in stride and thus far the clergy is very lenient with him provided he only refers to Copernican notions as "hypothetical".

Galileo is a devout Catholic, and is in no way trying to undercut the Church. He is pretty certain that Copernicus was right, though, and now that, thanks to him, everyone has a telescope, he is afraid the Protestant astronomers in Germany and elsewhere are going to arive at some proof the earth revolves around the sun, and he doesn't want the Church to be characterized as backward and illogical by these heretical enemies of the Church. He's working, very subtly, to get the policy about the heliocentric universe revoked.

8. Aug 31, 2005

### Math Is Hard

Staff Emeritus
hmmm.. now I am wondering if that's what got his nose snipped off..

9. Aug 31, 2005

### zoobyshoe

It proves the truth of Newton's remark about standing on the shoulders of giants. Galileo was doing some unbelievable grunt work to prepare the way for he elegant mind of the Englishman, by cracking apart 2000 years of calcified nonsense.

10. Aug 31, 2005

### zoobyshoe

There were no physicists back then, only philosophers and it isn't surprising that such things as laws of motion weren't arrived at by experiment but by developing explanations that were philosophically pleasing. I'm sure it was an enormous shock to encounter someone who thought that explanations of Nature should have something to do with the reality.
It wouldn't surprise me. The philosophers were, apparently, willing to go to great lengths to prevent reality from interfering with their ideas.

11. Aug 31, 2005

### zoobyshoe

A bit of googling reveals that his adversary was not a philosopher but a mathematician and the point of conflict was one of mathematics. Which probably means it's a good thing that the internet keeps people in the math forums physically separate.

12. Sep 1, 2005

### cragwolf

Yes, do not trust popular notions of anything. Science is not immune from its own historical myths and biases, even including recent affairs like the Sokal hoax. A very good article on the subject of the Galileo affair can be found here:

http://www.galilean-library.org/galileo1.html

Doubt and skepticism are your friends.

13. Sep 1, 2005

### zoobyshoe

The book seems to be following this "de-mythified" version very closely. It's more interesting reading, though, with inclusions of descriptions Galileo's love of gardening, his mysterious chronic illness, and other touches that make him more vividly human.

That site does a really excellent job with things like the in-depth explanation of the importance of the patronage system, and how it operated, which the book is more sketchy about (so far, anyway).