I highly recommend (sci-fi author) Micheal Flynn's (long-ish) chronological timeline on the series of events that led the general consensus going from Ptolemaic system to heliocentrism:
We tend view things in hindsight and judge people with our 20/20 view, when events really unfolded over a period of time, and so people made decisions with imperfect knowledge.
Two things that people forget or don't know: (a) Galileo was technically wrong, since he insisted on Copernicus' circular orbits, and it was Kepler that got it right (with elliptical orbits). And (b), it was not until 1806 that the Earth's motion was demonstrated through parallax (150+ years after Galileo died), at which point heliocentrism was more than simply an untested hypothesis.
Regarding (a) and (b) together: people when from Ptolemy to Kepler by the 1690s not because they had proof that it was true, but mainly because it made the answer easier. Ptolemy worked reasonably well mathematically at predicting orbits, it just took a damn long time.
Great points. For a quick summary I suggest reading the highest rated answer to this Physics SE question: https://physics.stackexchange.com/questions/26291/why-did-th.... The keypoint that most people fail to realize is that "Ironically, geocentrism persisted because the ancients were decent scientists and were unimpressed by (pre-Kepler) heliocentrism's failure to support itself with observational data."
"We tend view things in hindsight and judge people with our 20/20 view, when events really unfolded over a period of time, and so people made decisions with imperfect knowledge."
I think the same when people think Newton was crazy for pursuing alchemy. With hindsight it's clear that this wouldn't work but with the information he had at the time this was not so clear.
To be fair, the alchemists have accomplished virtually every one of their goals via a mixture of chemistry, particle physics, and electrical engineering invented by alchemists, their academic students, their students' students, etc (that is, from the academic tree rooted in the alchemists) --
- Life expectancies are soaring.
- Wounds that easily would've been fatal in 1850 are routinely survived by even the poor or middle class.
- Diseases of every variety are being tamed or eradicated.
- You can transmute elements, if you try hard.
- We've weaponized transmuting elements, at least two different ways.
- We've invented machines and materials that embody some human faculties, eg the ability to perform logic.
- We're making significant progress on artificial souls.
- We've created several varieties of artificial life.
I think people who regard the alchemists as failures are completely nuts and exactly the sort of people rebranding and marketing work on. Science is nothing but rebranded magic -- to the point if you substitute nouns with unfamiliar words, it sounds like magic out of a book. (Go on -- try explaining how cellphones accessing Wikipedia works at the level of electrons and photons with entirely new nouns in place of the familiar ones.)
For fun, we can even argue about if LIGO is actually just a successful version of the Michelson-Morley experiment and the detection of gravitational waves is also a confirmation of the existence of an aether. (It's obvious why M-M was a failure, given that it was trying to detect a much weaker effect with much less sensitive equipment.)
> Galileo's Daughter: A Historical Memoir of Science, Faith, and Love is a book by Dava Sobel. It is based on the surviving letters of Galileo Galilei's daughter, the nun Suor Maria Celeste, and explores the relationship between Galileo and his daughter. It was nominated for the 2000 Pulitzer Prize for Biography or Autobiography.[1]
Maybe we couldn't distinguish "the earth goes around the sun" from "the sun goes around the earth" until 1806, but we could tell that the other planets have the sun, rather than the earth, as their primary much earlier than that.
Isn't that the most important difference between the systems?
In the second episode, we saw a slew of new telescopic discoveries during 1610-1611; viz., the mountains on the moon, the Medicean stars, and (more decisively) the phases of Venus. Now the first two do not demonstrate geomobility, not do they undermine geostationarity. The first indicates that the moon is not incorruptible. But this is agreed to by theology, and it undermines only Aristotelian physics. The second indicates that some heavenly bodies -- Cosmo, Franco, Carlo, and Lonzo -- circle Jupiter and not the Earth. This bothers Aristotelian physicists, but not Tychonic astronomers. Only the phases of Venus KOs Old Man Ptolemy.
But eliminating Ptolemy does not prove Copernicus any more than eliminating Darwin would prove ID. There may be [and were!] other alternatives. When Ptolemy was ptossed, astronomers flocked... to the Tychonic and Ursine systems -- because none of the telescopic observations have so far established the motions of the Earth.
No, because there was a system (the Tychonic system IIRC) where the sun orbits the earth and the planets orbit the sun. It seems to have been popular at the time also.
This series is rather spoiled by the author's determination to trash Galileo's reputation. While he definitely has a point about simplistic, hagiographical accounts of Galileo's contributions, especially those that present geocentrists as being blind to the obvious, he goes on about it at length, introducing some rather weak and self-serving arguments along with the valid ones.
I don't see this as spoiled by any kind of determination to trash Galileo's reputation. Pointing out the reality of Galileo's situation is exactly the point, and to people who believe Galileo's fairy tale, of course that's going to hurt his reputation.
This account is actually more careful and nuanced than other accounts of the Galileo trial that I've come across.
Another possibly useful insight into Galileo is that he ridiculed Kepler for suggesting that the planets would have elliptical orbits. Galileo could never make his heliocentric model fit the observations, and meant he couldn't convince anyone that it was correct, because it wasn't. Kepler basically saved heliocentrism by proposing a model that worked, and Galileo mocked him for it, because he found non-circular orbits as ridiculous as others found his heliocentric model.
Galileo did a lot of important other work, but in the past his role in proving the heliocentric worldview has incorrectly been painted as unrealistically saintly. He was about as wrong as he was right, and he was self-centered and careless.
I am careful about Galileo. You see a lot of Catholics trying to rewrite history by presenting the Galileo trial as a simple scientific debate where Galileo lacked proofs of his hypothesis.
Actually I find it very suspicious that the author of this article skips the trial altogether.
We have the minutes. We have the judgement. Even if Galileo was an ambitious asshole Ith political afterthoughts, one important fact remains: The Church used the literal interpretation of the Bible to contradict a scientific theory.
This is the main point and the main problem of the Galileo trial and why it is significant. Galileo deserved opposition in a debate, not condemnation in a religious tribunal. It happened and the blame is solely on the dogmatism of the church. From this point, science diverged more and more from religious teaching and stopped seeing the church as an ally.
I haven't seen any Catholics yet trying to rewrite this history. I have seen atheists correcting incorrect beliefs about this period of history. I'm protestant and not a fan of the RC church hierarchy, but I do care about an accurate representation of history, and the Galileo trial is muddled with fairy tales and misinterpretations, because people don't know the context.
But whatever your religious beliefs are, Galileo did lack proof. His model was wrong. His idea was correct (though originally from Copernicus, of course). But without proof, and without a correct model (which Kepler later provided) there was no way at the time they could know it was correct. There was simply no scientific basis yet to accept it over the existing geocentric model.
The RC Church's position on science was not homogenous. Various officials have said that if an interpretation of the bible ever conflicted with verifiable observations, then clearly the interpretation of the bible must be incorrect. Obviously not everybody agreed, but heliocentrism did have its supporters within the church. It was not considered heresy until Galileo made his position impossible and alienated his biggest fan (pope Urban). In any case, Galileo's theory here, his model, was simply incorrect, and they knew it. There was a solid scientific basis to contradict it. They did pile on a bunch of other accusations, but that's primarily because he angered the wrong people.
Galileo did receive opposition in debate. His problem is that he didn't accept it. He wanted everybody to accept his model, despite the lack of a scientific basis for it.
> But whatever your religious beliefs are, Galileo did lack proof. His model was wrong.
You know who else lacked proof? It didn't bother you just as it didn't bother the inquisition. Maybe try using the same standards for those theocrats as you apply to Galileo.
The whole point is that geocentricism wasn't just dogma, it also happened to match observations. It was the null hypothesis, if you will, and Galileo failed to disprove the null hypothesis.
Geocentrism could not explain retrograde motion of inner planets. This alone disqualify it as a serious hypothesis. Galileo may not have had solid proofs but geocentrism made absolutely no sense.
Geocentrism only selling point was dogma: the idea that our planet was important and had to be in the center of the universe. That was the main reason to defend it.
Geo heliocentrism was an attempt to keep this, but really, it makes little additional sense: it is basically a frame substitution for a heliocentric model and required some orbits to cross each other if you wanted to assume the outer planets orbited the Earth.
Galileo had no solid proofs but lots of evidence: respective sizes of Earth and sun (there was an intuition that bigger objects were harder to move) the fact that other planets have moons.
The fact that a man had to fear for his life for having an opinion doesn't bare mentioning? All Galileo had to do was follow the rules as set out by the Inquisition, and all would have been well.
Is it a fact that he had to fear for his life? We're not talking about the Spanish Inquisition or an accusation of witchcraft here. He was questioned and got house arrest.
Of course it's still not good to get punished for dissing the pope according to our modern freedom of speech, but in those days, insulting rulers was still frowned upon. And Galileo went well beyond simply having an opinion; he insulted the pope. Not merely by ignoring the pope's instruction to present both alternatives in a balanced way, but by putting arguments from the pope (a good friend before this) in the mouth of a character called "Fool" (Simplico).
No. Galileo feared for his life more than once during decades of persecution. He was lucky to avoid torture. Read Heilbron's biography, or even just Wikipedia.
This notion that Galileo insulting the pope was some sort of rhyme and reason for his persecution is wrong. It's commonly accepted that Galileo had no intention of insulting the pope, and the pope didn't take it as an insult (Heilbron goes into much detail) . There is some minor evidence involving the rumour that someone suggested to the pope that it looked bad, but this is not at all the central reason for his persecution.
Did you get this from the Dava Sobel book? It's takes an awful license with history. Her Longitude book is the same, it's just wrong in so many aspects while presenting itself as accurate.
The church did not call Galileo's position unfounded. It called it absurd and heretical. To justify the latter it quoted the literal interpretation of the Bible.
"Galileo was fully aware that if his wished to cash in then he had to get his priority claim in tout suite....Now he had hit the jackpot and needed to cash in fast. He bunged his principal discoveries together in book form....his ego inflated by his recent successes....the sycophantic cheers of [Galileo's] high powered fan club....Beguiled by his silver tongued friend Barberini gave Galileo permission to write and publish a book....it is safe to say that he got stamped on for his hubris....Galileo was never the fearless defender of scientific truth or freedom of speech that his modern fan club like to present him as. He was an extremely egotistical social climber with an eye on the main chance, his own undying fame"
I think it's safe to call this an attack on Galileo's reputation. It does match my fuzzy understanding that the story we got in elementary school was not that accurate, but on a personal level, it's pretty mean spirited.
In particular, to modern ears, it's pretty jarring to hear a man convicted over scientific arguments described as being "stamped on for his hubris".
Exactly. It reminds me a lot like the defenders of the Soviet Union's house arrest of the dissident Andrei Sakharov -- the argument was, "He should have known what the reasonable limits of criticism of the government were. And the authorities didn't shoot him or anything the way they would have done in Stalin's time, so they were being quite reasonable".
* http://tofspot.blogspot.com/2013/10/the-great-ptolemaic-smac...
We tend view things in hindsight and judge people with our 20/20 view, when events really unfolded over a period of time, and so people made decisions with imperfect knowledge.
Two things that people forget or don't know: (a) Galileo was technically wrong, since he insisted on Copernicus' circular orbits, and it was Kepler that got it right (with elliptical orbits). And (b), it was not until 1806 that the Earth's motion was demonstrated through parallax (150+ years after Galileo died), at which point heliocentrism was more than simply an untested hypothesis.
Regarding (a) and (b) together: people when from Ptolemy to Kepler by the 1690s not because they had proof that it was true, but mainly because it made the answer easier. Ptolemy worked reasonably well mathematically at predicting orbits, it just took a damn long time.