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Thread: Is scientific method obvious?

  1. #61
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    Maybe he didn't really care about the phases of the moon and had no reason to think about it.

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    Quote Originally Posted by Mudskipper View Post
    oh I definitely believe in false memories, but I think this wasn't.....I was an adherent to Arthur Janov's primal therapy stuff for years, but I am very doubtful of it now, but a lot of the theory still makes sense to me.....that childhood memories are all still there but buried in the emotional stress, of the age, which must be blocked from awareness. That's why some people remember more of their childhood than others...less stressful childhood means more access to memories, and feelings etc.
    Of course, one of the features of false memories is that people think they're not false memories.
    Neuroscience (surprise!), says that Janov (and Freud before him) were just making stuff up. It seems we forget our early childhood because of the rapid turnover in hippocampal neurogenesis at an early age (2MB pdf).

    Grant Hutchison

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    Yea, John Lennon who went to have primal therapy directly with Janov later said it didn't work, but I still wonder if it works with some people. Janov always talked about hard-drug addicts having success with it, and I wonder if maybe they are the only people that might have success with it, and other people that go to have it, he just milks for their money. He always talks about abreactions, ie false 'primals', and anyone who claims it didn't work, he says just weren't suitable for the therapy.
    I sort of wish I had never read his books, as I find the ideas damaging, yet hard to shake.
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    Quote Originally Posted by grapes View Post
    I'm impressed with Ken's statistic of half of all people saying the earth's shadow causes moon phases. I tried to look it up, and found a lot of planetarium websites (of course they would say it's a common misconception!), but no statistic. Now, I'm trying to visualize a survey question that would fairly elicit that info.
    This is something we include in our pre-tests for intro astronomy classes (part of the process to document that students are learning something). Way over half of incoming college students will give some version of this answer relating the Earth's shadow to lunar phases. This does not seem like a very obvious (mis)interpretation to me, so I've mused about a widespread cabal of rogue 4th-grade teachers implanting the idea. What bothers me about it is how easy it is to see evidence that it's not true, once the question has been asked.

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    the simple rebuttal of the Earth shadow on the moon idea is to ask people what the moon looks like at half-moon...
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    Quote Originally Posted by ngc3314 View Post
    This is something we include in our pre-tests for intro astronomy classes (part of the process to document that students are learning something). Way over half of incoming college students will give some version of this answer relating the Earth's shadow to lunar phases. This does not seem like a very obvious (mis)interpretation to me, so I've mused about a widespread cabal of rogue 4th-grade teachers implanting the idea. What bothers me about it is how easy it is to see evidence that it's not true, once the question has been asked.
    I must say things aren't lookin' up (sorry), though they would do well to take Yogi's advice..."You can observe a lot by just watching."

    Also, I'd like to see any hard evidence on this. I got an email today to met in a few weeks the new education person with McDonald and this evidence might be an interesting addition.
    Last edited by George; 2017-Sep-29 at 09:10 PM.
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    I'd say that the whole issue stems from the two very separate ways that people use theories. First there are the theories we need (consider your own list), these are the theories that constantly make predictions for us because that's why we have them, and we are constantly checking these theories because that's why we need them-- to make predictions we can use to better our lives when they work.

    Then there is the other type of theory, one that we don't need to make predictions. Instead, we need this type to give us a "warm fuzzy feeling" of understanding something. Since the theory makes no predictions for us, we don't test it, and worse, to test it would be to spoil the whole purpose-- if the purpose is to create the illusion of understanding, why mess with the illusion? Testing can only ruin the purpose of theories like this. Consider your own list of this type of theory-- we see it everywhere, particularly in the realm of "ideology". And of course, for most people, theories that explain the phases of the Moon are clearly of this second type-- we don't need it to make predictions, because the Moon will go about its phases either way and we really don't need to know what the phase will be or why it will be that, we only want to have a sense of knowing. It might be a little sobering for us to tally how much of what we think we know falls into this latter category.

    By the way, the utter failure of the idea that phases are caused by the shadow of the Earth was demonstrated to me with crystal clarity at the recent total eclipse of the Sun. An hour before the beginning of the eclipse, an old timer at the hotel I was at said "there must be some kind of mistake, how can the Moon eclipse the Sun today? The Moon isn't there." The sheer brilliance of that observation stands in marked contrast against how utterly wrong it is.
    Last edited by Ken G; 2017-Sep-30 at 12:07 AM.

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    If anyone sees the moon and the sun in the sky, at the same time, if they put two and two together, they should realise............
    Formerly Frog march..............

    She was only a farmer's daughter, but she was outstanding in her field.

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    Quote Originally Posted by Mudskipper View Post
    If anyone sees the moon and the sun in the sky, at the same time, if they put two and two together, they should realise............
    Yet how many times have you heard hit said that "the Moon rises as the Sun sets..." ? Or, "the Sun rules the daytime and the Moon the nighttime," etc. Pick up pretty much any informal popularized account of the Sun and Moon, and that's what you see, over and over. So many people don't even realize it is possible to see the two at the same time! Sometimes the things we don't test are literally right in front of our eyes. What more subtle things that are right in front of our eyes are we not testing?

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    Plenty

  11. #71
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    Quote Originally Posted by Ken G View Post
    I'd say that the whole issue stems from the two very separate ways that people use theories. First there are the theories we need (consider your own list), these are the theories that constantly make predictions for us because that's why we have them, and we are constantly checking these theories because that's why we need them-- to make predictions we can use to better our lives when they work.

    Then there is the other type of theory, one that we don't need to make predictions. Instead, we need this type to give us a "warm fuzzy feeling" of understanding something. Since the theory makes no predictions for us, we don't test it, and worse, to test it would be to spoil the whole purpose-- if the purpose is to create the illusion of understanding, why mess with the illusion? Testing can only ruin the purpose of theories like this. Consider your own list of this type of theory-- we see it everywhere, particularly in the realm of "ideology". And of course, for most people, theories that explain the phases of the Moon are clearly of this second type-- we don't need it to make predictions, because the Moon will go about its phases either way and we really don't need to know what the phase will be or why it will be that, we only want to have a sense of knowing. It might be a little sobering for us to tally how much of what we think we know falls into this latter category.

    By the way, the utter failure of the idea that phases are caused by the shadow of the Earth was demonstrated to me with crystal clarity at the recent total eclipse of the Sun. An hour before the beginning of the eclipse, an old timer at the hotel I was at said "there must be some kind of mistake, how can the Moon eclipse the Sun today? The Moon isn't there." The sheer brilliance of that observation stands in marked contrast against how utterly wrong it is.
    Ken, I am sorry but you have lost me here, and my hunch is that you are overthinking something. Let me repeat that this is only a hunch, not a logical inference from analysis of any sort of data.

    My dad was a brilliant electronics and radar engineer whose work was in radar as an aid to navigation. As an adjunct to his electronics work he did continual updating of the orbital elements of U.S. Navy beacon satellites as they were perturbed by Earth's lumpy gravitational field. He showed great skill in the mathematical techniques for fitting curves to messy data, and made reliable and useful predictions that enabled the satellites to be reliable navigation references. At the same time he thought the figure 8 shape of the analemma was due purely to orbital eccentricity and that with a circular orbit the noon Sun's annual line of position would have been an oscillation along some sort of slanted line. I told him, "No, it would be a symmetrical figure 8. I can demonstrate it on a globe or on my Norton's Star Atlas charts." This is somewhat more complicated than the lunar phase issue, but I see it as analogous. I don't know whether he inferred that on his own or was misinformed by someone. For all I know he could have tried to work it out in his head and muffed it in the process. In any case, whatever error he made was not on something that occurred in his satellite orbital element work and thus was of no professional consequence. I have no way of knowing whether or not he had a warm and fuzzy feeling about his mental picture of the analemma geometry. For all I know he could have had such a feeling about his success in tracking the satellites and none at all about the analemma. I can imagine that he may have been chagrined by my rebuttal.

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    The answer to this lies in the history that led up to it, and understanding the differences
    You're really not going to like it, the meaning of life the universe and everything is.... is.... 42!
    What??????
    is that all you have to show for 7.5 million years of work?????
    it was a tricky assignment.

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    Quote Originally Posted by Hornblower View Post
    I told him, "No, it would be a symmetrical figure 8. I can demonstrate it on a globe or on my Norton's Star Atlas charts." This is somewhat more complicated than the lunar phase issue, but I see it as analogous. I don't know whether he inferred that on his own or was misinformed by someone. For all I know he could have tried to work it out in his head and muffed it in the process.
    But that's exactly why it is not analogous to the phases of the Moon-- there's no way anyone can see a crescent Moon, with the Sun nearby, and possibly think that the effect is being caused by the shadow of the Earth. That's not a "muff" that is at all possible. Ergo, the only other possibility is that he never noticed the situation I just described. But anyone who wanted to test their theory of the phases of the Moon would of course notice that situation, in the course of testing their theory, it's a prime opportunity for such a test if that were their goal. Ergo, it wasn't their goal-- it served their purpose without being tested, so it was never the purpose of the theory to pass tests, it was always the purpose of the theory to give a feeling of understanding, period. That's my whole point, he sounds like an absolutely classic example of what I'm talking about, because he would have been way too smart to hold to that theory for any other reason. In fact, I would argue that smart people tend to be even more susceptible to holding to theories just to get a sense of knowing-- such people are used to knowing, so they are uncomfortable not knowing, and may thus be susceptible to drawing premature conclusions. Being smart, and being confident in one's smarts, does not mean you tend to test more-- it may mean you tend to test less.
    Last edited by Ken G; 2017-Oct-01 at 01:12 AM.

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    I believe the scientific method is a proceduralization of fact based inquiry and it is not obvious. It probably took many leaps in thinking to get to it.

    Without it, we still achieved much because we are intelligent. But even animals ( la Pavlov) exhibit the ability to do basic observing and concluding.

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    Quote Originally Posted by Ken G View Post
    But that's exactly why it is not analogous to the phases of the Moon-- there's no way anyone can see a crescent Moon, with the Sun nearby, and possibly think that the effect is being caused by the shadow of the Earth. That's not a "muff" that is at all possible. Ergo, the only other possibility is that he never noticed the situation I just described. But anyone who wanted to test their theory of the phases of the Moon would of course notice that situation, in the course of testing their theory, it's a prime opportunity for such a test if that were their goal. Ergo, it wasn't their goal-- it served their purpose without being tested, so it was never the purpose of the theory to pass tests, it was always the purpose of the theory to give a feeling of understanding, period. That's my whole point, he sounds like an absolutely classic example of what I'm talking about, because he would have been way too smart to hold to that theory for any other reason. In fact, I would argue that smart people tend to be even more susceptible to holding to theories just to get a sense of knowing-- such people are used to knowing, so they are uncomfortable not knowing, and may thus be susceptible to drawing premature conclusions. Being smart, and being confident in one's smarts, does not mean you tend to test more-- it may mean you tend to test less.
    Aristotle was undoubtedly smart but made some basic mistakes both in observations and introspection, which survived as dogma for more than a thousand years. I have to admire those who Challenged dogma and were ridiculed for it. Some you have to wonder about. Marconi believed he could send radio across the Atlantic but he was right for the wrong reasons. The shift from philosophical reasoning to really testing was an intellectual leap, part of the enlightenment when dogma about what God wanted was challenged. The formulation of method as in Popper, was a slow jump that has not really become public yet. People are ignorant and superstitious and still wary of science. So no, it's not obvious at all.
    sicut vis videre esto
    When we realize that patterns don't exist in the universe, they are a template that we hold to the universe to make sense of it, it all makes a lot more sense.
    Originally Posted by Ken G

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    Quote Originally Posted by Tom Mazanec View Post
    He was also a deer hunter. When I read "Bambi" as a child, I went into a deer reading frenzy (aspie). I mentioned to him that bucks shed their antlers once a year. "ARE YOU CRAZY!? A DEER CAN'T GROW A HUGE RACK LIKE THAT IN A YEAR!".
    He later apologized to me.
    I think this is an example of one of those unexamined assumptions that we all keep turning up in our lives.
    Many hunters only ever see a deer in the hunting season, when it has fully formed antlers. So they miss out on the spring cycle of shedding and regrowth in velvet. And of course many animals we see all year round don't shed horns - cows and sheep, for example. So there's a sampling error that leads to the default assumption that deer antlers work like cow horns.
    There are observations that might lead to questions - shed antlers on the ground, for one, and the fact that older deer have more tines on their antlers than younger deer. Once these are pointed out, they create a puzzle that might make you want to go out to look at deer in other seasons.

    But it's amazing how difficult it is to notice things that conflict with unexamined assumptions. So maybe another component of the scientific method is cultivating a disposition to poke at everything, to consider what it implies and what it doesn't imply. We have pretty good mechanisms now (although patchily used) to ensure we don't fool ourselves with badly designed tests. But we don't have so many mechanisms that help us reliably spot our invisible assumptions.

    Grant Hutchison

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    Quote Originally Posted by profloater View Post
    Aristotle was undoubtedly smart but made some basic mistakes both in observations and introspection, which survived as dogma for more than a thousand years. I have to admire those who Challenged dogma and were ridiculed for it. Some you have to wonder about. Marconi believed he could send radio across the Atlantic but he was right for the wrong reasons. The shift from philosophical reasoning to really testing was an intellectual leap, part of the enlightenment when dogma about what God wanted was challenged. The formulation of method as in Popper, was a slow jump that has not really become public yet. People are ignorant and superstitious and still wary of science.
    Ah yes, good point about Popper-- he tells a story of how he came to understand the pitfalls in semi-scientific thinking (not his word, but it seems to fit). He had a colleague who had a theory of psychology that he claimed was quite general. At first Popper was impressed by the theory, but then he read of a case that seemed to go completely opposite the predictions of the theory. When he told his friend about the case, he expected his friend to say something like, there might be exceptions that require further scrutiny, etc. But instead, his friend just reinterpreted the case, via hindsight, to make it sound like it fit the theory! Popper realized that the theory was not about making successful predictions at all, it was about providing an illusion of understanding. This insight was seminal to his reformulation of the key elements of scientific thinking.

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    Quote Originally Posted by grant hutchison View Post
    But it's amazing how difficult it is to notice things that conflict with unexamined assumptions. So maybe another component of the scientific method is cultivating a disposition to poke at everything, to consider what it implies and what it doesn't imply. We have pretty good mechanisms now (although patchily used) to ensure we don't fool ourselves with badly designed tests. But we don't have so many mechanisms that help us reliably spot our invisible assumptions.
    Exactly, which is why I so often point out the pitfalls in the whole concept of an "assumption" in science. Many people seem to think an assumption is like a mathematical axiom-- something that you regard as true because it really seems like it should be, and even though you know there could be situations where it isn't true, you simply aren't interested in those situations. But assumptions in science shouldn't be thought of like that at all-- they should be tended like gardens, constantly remembered that they are in the background of all our conclusions. All they are is a kind of prioritization of what we are choosing to spend our time and energy to test-- the "assumption" is simply the thing we are less concerned about testing because we think it is more important to test something else. The fallacy, of course, is when we never go down the list-- we test the thing we were most concerned about, get a satisfactory result, and then commit the cardinal sin of science-- we stop! That's because we forgot the difference between an assumption in science and an axiom in mathematics.

    The classic example of this phenomenon was Copernicus and Ptolemy. The Greeks were not interested in testing the "assumption" that stars could not be a million times farther than the Sun, so they were not interested in the possibility that stars were suns. Stars not being suns was the centerpiece of the geocentric model, but it was never an axiom, it was always just something that was hard to test and seemed unlikely, somehow. So when it got turned from a lower priority test to an axiom, the Earth went from being "the stationary center of the universe unless stars are suns" into "the stationary center of the universe, period." That's how assumptions should not be used in science.

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    Quote Originally Posted by Chuck View Post
    Maybe he didn't really care about the phases of the moon and had no reason to think about it.
    Exactly. Unless you're an astronomer the whole issue of the origin of the Moon's phases is trivia. (And judging people by how much trivia they know seems to be a bad thing to me.)

    I recall a Dilbert cartoon where the cartoonist was decrying that "extensive knowledge of trivia, combined with arrogance" is often mistaken for intelligence.
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    I meet people regularly who do not know about the 28 day cycle, they just never thought about it and if they were ever taught it slipped away as irrelevant stuff. City dwellers do not catch sight of the moon often. For them indeed it is trivia, like which side was (pick a country) on during WW2. And to understand scientific method, ? Just another irrelevance. Something somebody else does when they don't have to work. Am I getting bitter? I now have to explain to professional electricians what a relay is and why inductive loads trip RCDs (GFCIs) not just science but technology is getting remote from the majority, it'S not good. Is it?
    sicut vis videre esto
    When we realize that patterns don't exist in the universe, they are a template that we hold to the universe to make sense of it, it all makes a lot more sense.
    Originally Posted by Ken G

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    Quote Originally Posted by plant View Post
    Greeks-> Romans take on Greek Culture-> dark age texts copied by Muslim Scholars->The Reformation (Germany) -> The Renaissance (Italy): $$$ talks> American/French Revolution->The Enlightenment (France & Britain)-> The industrial Revolution (Britain) due to lots of coal underground.
    I think the issues are:
    1) an uneducated serf chatting to 3 other serfs in a field covered with horse-sh@t is not going to have a gedanken experiment.
    2) you need a population of literate people living in cities
    The development of agriculture (1) can be considered a scientific process (noting that selecting certain plants can lead to better crops) preceded the development of cities (2).

    I think most of the other items in your list are equally wrong and/or irrelevant.

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    Quote Originally Posted by Mudskipper View Post
    If anyone sees the moon and the sun in the sky, at the same time, if they put two and two together, they should realise............
    There was an entire thread recently about whether the relationship between the positions of the Sun and Moon, and the phase of the Moon was "obvious" ... it was quite heated, as I remember.

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    Quote Originally Posted by Strange View Post
    There was an entire thread recently about whether the relationship between the positions of the Sun and Moon, and the phase of the Moon was "obvious" ... it was quite heated, as I remember.
    Oh, yeah. That was a great one.
    And then there was the one about whether the gibbous moon is "obviously" not aligned with the sun when they're both in the sky at the same time.

    Maybe we should have infraction points for anyone who advances an argument involving the phrase "it is obvious that ..."

    Grant Hutchison

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    Perhaps it is obvious to some 3 year-old aliens that e=mc^2.
    Formerly Frog march..............

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    Quote Originally Posted by Ken G View Post
    Exactly, which is why I so often point out the pitfalls in the whole concept of an "assumption" in science. Many people seem to think an assumption is like a mathematical axiom-- something that you regard as true because it really seems like it should be, and even though you know there could be situations where it isn't true, you simply aren't interested in those situations. But assumptions in science shouldn't be thought of like that at all-- they should be tended like gardens, constantly remembered that they are in the background of all our conclusions. All they are is a kind of prioritization of what we are choosing to spend our time and energy to test-- the "assumption" is simply the thing we are less concerned about testing because we think it is more important to test something else. The fallacy, of course, is when we never go down the list-- we test the thing we were most concerned about, get a satisfactory result, and then commit the cardinal sin of science-- we stop! That's because we forgot the difference between an assumption in science and an axiom in mathematics.
    Nicely stated! It is harder to excuse untested assumptions in the realm of science vs. other realms, though some comments are only meant to sound objective-based when they are just social comments stated for various reasons. When I was little I noticed the strange, thin black cloth stapled underneath our couch and asked my mother if it was fire-proof, thinking it may be there as fire protection. She casually said yes. I was amazed that I had guessed right so that night, after all were asleep, I decided to test her claim. She was surprisingly wrong! In panic, I grabbed only a small glass to shuffle back and forth with water. I don't recall if the fire department came on this particular occasion but it was quite a scene. It puzzled me why Mom was so tolerant of my bad behavior, calming Dad as well. I do know she really liked her new couch.

    I think it's easier to make careless comments with more abstract things, which includes anyone who doesn't take certain sciences very serious due simply to lack of interest. With Mom, she was just more interested in something else and perhaps thought it wise to not say, "I don't know". Maybe she feared I would test the cloth to find the answer.

    The classic example of this phenomenon was Copernicus and Ptolemy. The Greeks were not interested in testing the "assumption" that stars could not be a million times farther than the Sun, so they were not interested in the possibility that stars were suns.
    Is this not an assumption? Hipparchus used parallax to accurately determine the distance to the Moon. Perhaps they had already tried this with the stars, which would have been evidence that they were fixed. Am I forgetting something?

    Stars not being suns was the centerpiece of the geocentric model, but it was never an axiom, it was always just something that was hard to test and seemed unlikely, somehow. So when it got turned from a lower priority test to an axiom, the Earth went from being "the stationary center of the universe unless stars are suns" into "the stationary center of the universe, period."
    Hmmm. I don't see why the Earth-center model condition that stars are not suns was the key to the model. Back then, little bitty suns would be as valid a claim as stars about the same size of the Sun, and the inverse square law for light might not have be around, though I'm too rushed to check this idea out.
    Last edited by George; 2017-Oct-01 at 09:06 PM.
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    Quote Originally Posted by George View Post
    NI don't recall if the fire department came on this particular occasion but it was quite a scene. It puzzled me why Mom was so tolerant of my bad behavior, calming Dad as well. I do know she really liked her new couch.
    Perhaps she had a guilty conscience-- thinking the couch was fire retardant when in fact it was a fire hazard!
    With Mom, she was just more interested in something else and perhaps thought it wise to not say, "I don't know". Maybe she feared I would test the cloth to find the answer.
    Apparently your desire to test was activated all the same. Science does have a place for those who test what is commonly known, not just what is "on the frontier"!
    Is this not an assumption? Hipparchus used parallax to accurately determine the distance to the Moon. Perhaps they had already tried this with the stars, which would have been evidence that they were fixed. Am I forgetting something?
    The problem with parallax is that it deals in apparent motions, so it only tells you ratios of distances. So you can put an upper limit on the movement of something only if you have an upper limit on the distance. Which was their problem in the first place! The Greeks knew they were only getting ratios, but they mistook an assumption for an axiom, so they thought they were safe in concluding that the Earth was stationary.
    Hmmm. I don't see why the Earth-center model condition that stars are not suns was the key to the model. Back then, little bitty suns would be as valid a claim as stars about the same size of the Sun, and the inverse square law for light might not have be around, though I'm too rushed to check this idea out.
    What I mean by "stars are suns" is that they are similar objects. That requires they be something like a million times farther away. Since the Greeks geocentrism was anchored on the absence of stellar parallax, they would have known their anchor was dragging if they had allowed themselves to imagine that stars are suns.

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    Quote Originally Posted by Ken G View Post
    The problem with parallax is that it deals in apparent motions, so it only tells you ratios of distances. So you can put an upper limit on the movement of something only if you have an upper limit on the distance. Which was their problem in the first place! The Greeks knew they were only getting ratios, but they mistook an assumption for an axiom, so they thought they were safe in concluding that the Earth was stationary.
    Yes, I was too quick on the trigger with this. The lack of parallax was the one big problem for Copernicus. While searching for parallax, it is interesting (serendipity) that stellar aberration was discovered before parallax.

    What I mean by "stars are suns" is that they are similar objects. That requires they be something like a million times farther away. Since the Greeks geocentrism was anchored on the absence of stellar parallax, they would have known their anchor was dragging if they had allowed themselves to imagine that stars are suns.
    Yes, but I don't expect this to have been a real concern. Glowing orbs of various sizes might have been easy for them to imagine, but vast distances were not. Ptolemy chose to put Venus between us and the Sun rather than beyond the Sun because he reasoned that God would not waste all that empty space. Such teleological reasoning likely existed for the earlier Greeks. Parallax, no doubt, would have made a difference, but I suspect it might have resolved itself with an early Tychonic model to "save the appearance".

    Aristotle's principles that elements go to their natural spot seems to me to be the key to their geocentric model. This explains all that was observed, though retrograde added some quirkiness. This model also favored a spherical Earth. His "first element" (aether) would be whatever they wanted to dream-up, no doubt, since the idea of getting samples would have made for some fun jokes.
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    I would not call the stars not being suns the centerpiece of the geocentric model. I would call Earth the centerpiece, with the idea that it is stationary being a reasonable common sense default at the time. The fixed stars were peripheral, and their lack of observable parallax reinforced the geocentric line of thought.

    The idea that God would not have wasted the space needed to place the stars far enough away to make the parallax from a moving Earth unobservable was a belief that was not supported by observational testing, and thus was not scientific by our present standard of scientific method. However, some critics of the moving Earth model thought they had a valid test. They thought a Sun-like body would be invisible if that far away. They did not yet understand that a sufficiently luminous body could be visible against a dark background in spite of being too small to be seen without that luminance. That would be hard to test with scaled down lights in those days because they probably could not make a torch that would be anywhere near as intense as the Sun.

  29. #89
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    Quote Originally Posted by Hornblower View Post
    The idea that God would not have wasted the space needed to place the stars far enough away to make the parallax from a moving Earth unobservable was a belief that was not supported by observational testing, and thus was not scientific by our present standard of scientific method.
    Agreed, they did enjoy reasoning such things. I'm finally reading Huygen's work about inhabitants on other planets and it's rich in subjective reasoning especially coming from someone of his intellect. His advocacy reminds me of some of Galileo's style.

    However, some critics of the moving Earth model thought they had a valid test. They thought a Sun-like body would be invisible if that far away. They did not yet understand that a sufficiently luminous body could be visible against a dark background in spite of being too small to be seen without that luminance. That would be hard to test with scaled down lights in those days because they probably could not make a torch that would be anywhere near as intense as the Sun.
    That's a great point. This reasoning, though erroneous, would indeed reinforce their Geocentric model. They could have imagined, alternatively, that stars were even bigger than the Sun to suggest their possible vast distances but at the risk of being mocked, no doubt.
    We know time flies, we just can't see its wings.

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    An issue that I only recently was brought to appreciate about the geocentric-heliocentric debate was that some people were trying to measure the apparent sizes of stars (not yet having the optics to understand that the naked-eye, or for that matter telescopic, disks of stars are optical rather than physical) and pointed out that stars far enough away to not show obvious parallax would have had to be so large as to be nothing at all like the Sun. I may have linked it before, but a very detailed historical discussion, by a historian of science, provided in The Great Ptolemaic Smackdown (stay for all 9 parts, it's worth it). Short form: it was way more complicated, more people were important at the time, and what we like to present as the Cartoon Network thread of discovery wasn't at all so obvious at the time.

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