Yes I agree, you have highlighted similar sources of potential confusion previously, such as the phrase "it's just a model" which I admit to having used more than once. It is easy to fall prey to the notion that a model is a poor substitute for the actual when in fact, as you say, the model is the interface between our limited intelligence and the actual - hardly any kind of superficial notion then, in fact more of an essential survival mechanism.

A model is usually a simplification of reality, but that's a good thing when reality is dumbfoundingly complex. If science had started off by trying to explain the world exactly in all its richness of detail, and never settled for anything less, it would never have got anywhere.

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"A witty saying proves nothing" Voltaire.
"All your bias are belong to us" Ara Pacis.

Which of our golfer's putts is the one true putt? The notion of absolute truth doesn't always work that well. I'm arguing against the utility of comparing what we do or try to do against some alleged Platonic Ideal, some "absolute truth." Note that I am not saying "do whatever you want, anything goes." I am saying that, strictly speaking, there is no literal model, there is no literal "absolute truth", and there is no means to establish a correspondence relation between the two. The notion of models in regards to scientific theories makes us think that a theory is like a painting or a photograph of the object depicted. Science, I am saying, is a way of living--just like golf is. People get ahead in either endeavor in many sorts of ways. There doesn't always have to be one "true" technique that somehow stands holier than the rest.

Your reference leads me to an article discussing an experiment that was performed. What is the model here? Is it the words on the page? The meter readings from the lab equipment? The printed words of the theory published in a peer-review journal? Something in the heads of the scientists?

Here is a clear-cut instance of a model:

Copernican Solar System Model

What physically in scientific theory is like that plastic and metal assembly? (Is it the ink markings on the paper, etc.?)

As an aside, let me point out that being in possession of that solar system model does not make one adept at understanding and dealing with the solar system. You can use the model to teach someone about the solar system, but there is little to no gain in merely producing or possessing the model. We could say that the scientific knowledge is not contained in the model. But if we see our student pointing out planets in the night sky and describing their orbits, then we are more likely to feel that we are in the presence of scientific knowledge, even if we cannot put our finger on exactly what that is.

The objective is efficiency, making the most of our time and resources. Given a handful of observations, Newton (or Halley) could predict future positions of a comet. The "model," if there is one here, is the solar system itself. (Sometimes, the world can serve as its own model.) Newton discovered a method that allows predicting positions from a limited set of observations of that solar system. Newton did not need to construct a limited, sketchy replica of the solar system to simplify the problem. He just needed to discover the most relevant aspects of the solar system to handle the problem at hand.

Only for those who have no idea what a theory actually is.

And no one ever said there had to be. What does that have to do with models? Models do not claim to be the "one true" anything.
The model is what it is-- the model. Therefore, that is the answer to the question you pose here.
Indeed, no one ever said that "possessing" a model was all you needed to use one effectively. Did they?

__________________
Logic is the grammar of truth.

Meaning and absolute certainty are incompatible, and profound meaning and absolute certainty are profoundly incompatible.

The only thing intelligence is capable of is recognizing itself.

I agree that speaking of scientific theory as a model is a means of acknowledging that science can always improve. I quibble with the notion that way out in the distance there is "the actual" that science falls short of. When your theory fails, there is no "actual" sitting remotely at a distance. Think of any new drug introduced to the market that ends up harming or killing people. We do not live separately from the actual. We either master the world well enough or we don't.

But notice that science doesn't work that way at all. Science tests its theories to the utmost degree, but it never once compares some model to some deeper underlying reality. "Model" and "deeper underlying reality" are philosophical notions imposed on science. (I'm not suggesting that is bad.) The scientific method is an instance of a dynamic, closed-loop system where experimentation and peer review serve as correcting feedback for the overall process. The scientist, and his science, is embodied in the environment and does not stand isolated from it.

You have to define what you mean by "what we observe" on one side and "what that observation actually relates to" on the other. Pointing out instances of each would be best. Otherwise, it is not clear what sort of distinction is being drawn.

I observe a woman being sawn in two. In fact, it turns out there are actually two women concealed in the magician's box. There is a distinction here, but not between a model and a deeper underlying reality. I observe "the actual." The women in the box do constitute something "deeper," but perhaps you meant something more out of reach by "deeper underlying reality." It just so happens that some actual things look like other actual things from particular perspectives, that is, there is ambiguity in the light patterns, as the magician Teller says. Most importantly, none of this means I am in some way isolated behind a model. I'm in touch with the actual in all cases. I just come to master it better with experience and exploration.

I saw David Copperfield perform the sawing-in-two-trick, except he did it with himself as the subject. True, what was taking place on the stage was fake in one sense, but it was no representation of some other absolute reality. There was only one thing, the performance, not two. That performance was real. He was just taking advantage of the optical ambiguity such that it was visually consistent with being sawn in two.

The point here is that it is still possible to be in contact with actual, yet to be wrong. My examples with the golfer practicing his putts shows that as well. You don't need to introduce the model/absolute-reality dichotomy to explain why we are wrong. We can directly observe the actual and still screw it up!

About all I can recommend at this point is that you spend a day appreciating all the ways science has altered the way we live our lives. Science is not about an unreachable absolute. It's about grasping onto the reachable and exploring for more fertile grounds.

I'm really trying, Ken. I enjoy these discussions and partake of them in good faith. And I know how irritating I must be to others coming off as stubborn or as somebody who just doesn't get what seems obvious and in no need of explanation to most everyone else. One function of philosophical discussions, however, is to re-examine the obvious from time-to-time.

Just to speak clearly here, a person--not a model--makes predictions and unifies observations.

Well, I was hoping for something a little more clear-cut than in the mind of a baby, but on the other hand, that you chose this example is informative as to what you consider models to be.

But you are attempting an indirect argument for a model here when something a little more direct is called for. You observe a parent attend to the baby when it cries and the baby ceasing crying after it is taken care of. That's what is known to exist here. You then posit a model as a singular entity that explains the crying done afterward. That doesn't help me understand what a model is. All you have done is state the observed patterns of behavior and then said that a model causes it. We could more effectively just leave it at saying that the reason the baby cries is that its parents came to it when it cried. At least there would be a clear cause and a clear effect.

I entirely agree, but what we find when we examine the obvious is the obviousness of the importance of making models whenever engaging in intelligent thought.Actually, it is perfectly normal physics parlance to say that a model makes predictions. There is no imprecision there that isn't purely pedantic. Your objection is no different than objecting to the claim that an exception disproves a theorem, or that rain adds water to a puddle (only people can prove, only people can add, etc., etc.). A pointless distinction.
My point is that you can start anywhere you want in your own personal history of making models. It is probably the single most common activity of conscious intelligence, along with language (which itself has a close relationship with modeling, because language is nothing but syntactic relationships between labeled experiences, and the way we consciously understand and conceptualize our experience is pretty much uniquely via modeling it.) So in short, you ask, "what is a model", to which I respond, "what isn't?" Indeed, everything you say about behavior is not actually behavior at all, it is your model of behavior. (What is the act of putting, after all? Do I have to be using a putter to be doing it? What is a putter anyway? What is your model of a golf ball? None of the behaviors you describe are actually behaviors.)

No, that is not what I am doing at all, which is why I did not use those words. I went into the mind of the child, and asked, what is it thinking, when it actually starts to think, rather than simply reacting instinctively? Answer: it is thinking in terms of models. It is you who insist on considering your own model of what behavior is. Even in this very quote, you are modeling the interaction of a parent and a child. Maybe the parent strikes the child in anger, or ignores it. Maybe the parent runs, or walks. Maybe the parent gives it milk, or maybe changes the diaper. What did you mean when you said "observe the parent attend to the baby"? You obviously have some model in mind. If the parent ignores the baby, is that attending? You never actually observe anyone "attending" anything, you only observe movements of their body. "Attending" is just your own personal model of what they are doing (likely a model shared by many if not all onlookers). Luckily, we do indeed think in terms of models, with great efficacy, for language itself would be virtually meaningless otherwise.

The reason you claim to not understand what a model is is sheer obstinence. Virtually everything you say is making models, even now. You just used the word "understand", for example. What does that mean, anyway? You obviously have some model in mind for what constitutes understanding, even if that model is behavioral in nature (as I'm sure it is). Speaking in terms of behavior in no way avoids the need to make models, it's just another kind of model-- that is all you are doing.
I stated no such thing. Why on Earth would I state that a model "causes" anything? Models are mental processes we use to understand and predict-- causes are something entirely different. Indeed, the whole concept of "cause" is also a model. What do you think you mean by "causes it", what model do you have in mind there?

But one must of course recognize that even "cause and effect" is a model relationship. The actual relationship is simply that one thing happens, and then the other-- you model it as something else when you use that phrase.

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Logic is the grammar of truth.

Meaning and absolute certainty are incompatible, and profound meaning and absolute certainty are profoundly incompatible.

The only thing intelligence is capable of is recognizing itself.

How do you know that there is "no actual" at a distance, actually?

I've decided to focus on this point, in the hope that it will clarify your position for me. I'm not sure that I quite understand what your position is--what it is that you're criticising. A lot of what you say sound like things I agree with, and have argued for many times too in these forums. Yet other things you say sound a lot like the pop-postmodernist "anything-goes" epistemological talk of ID proponents. But then you say you are not saying "do whatever you want, anything goes". And I get confused...

My model of your worldview seems to be amiss... Evidently I need to make further observations.

__________________
"A witty saying proves nothing" Voltaire.
"All your bias are belong to us" Ara Pacis.

The crux of this seems to be defining the actual. You define it as the “here and now” - so, prior to GR, Newton’s laws were the “actual” but post GR are these laws seen as a simplification/model or are they still an "actual"? Is GR an “actual” waiting to be a simplification/model? I suppose that if one thought science was able to reach an “actual reality”, then one would be justified in saying that each step along that road could be the “actual”, but that surely is a huge speculation to make. It seems to me that as long as we cannot be confident with regard to the ultimate completeness of scientific explanations, then they can only ever be a model. The degree to which the model can be thought of as representing the “actual” is I think a very difficult question, which is why I think essentially it is a case of models all the way down to the fundamental levels of nature. And what do we find at that fundamental level?, well, a notion of reality that is mind independent and inaccessible.

I can see how one may consider the predictive element of (say) Newton's laws will always be valid within its domain (unlike the rather transitory nature of descriptive elements) and from this perspective it could be thought of as always being an "actual", but after all said and done it is still an incomplete representation.


Well we can’t compare the model to a deeper underlying reality simply because we would have no recourse to identifying in a scientific manner that reality. We may have philosophical notions, but those are hardly suitable for such scientific comparisons. But the very fact that we employ differing models logically points to a distinction between the models and a deeper reality.

In the case of my example (the electric field) engineers can observe the RF energy through instruments, they can observe that the adding, moving or changing the antenna elements can affect the energy levels received, and those measurements could be shown to relate directly to a concept of an electric field as a real propagating electric wave (ignoring the magnetic component). But what does this observation really relate to in a scientific (not engineering) sense? The changing electric field is not a familiar observable notion like ripples on a pond, it is a concept based entirely on notions that are not part of our every day life (our macroscopic reality). Those notions have been created by science as a means of representing measurements that we perform at a detector. I have no idea if those notions have a close resemblance or not to the underlying reality that allows us to observe a correlation between a source and detector separated in vacuum. Ken G pointed out that there are three different models that scientists use to explain this correlation, which one of them is correct? They are all correct of course in that they are all usable models of an underlying reality that underpins our macroscopic notion of EM radiation propagating between a source and sink.

We are never in touch with absolute reality other than through human representation, this is my point - and that human representation can only be a model since we can never access the absolute directly.

That I wouldn’t appreciate the role of science in our lives seems unlikely, what I did lack from science was a sense of what it was supposed to be telling us - notions of a reality consisting of “material” objects as particles or “photons in flight” seemed a bit fanciful to me. Yet I was aware that the science worked, so what was this scientific reality? Well what physics has told me is that there is a distinction to be made between scientific reality and the absolute. The latter exists in the absence of sentient beings, but at the most fundamental level is of a form that is inaccessible through science. The former gives rise to human representations that we label as atoms, photons etc, or in other words they are models.

Exactly. It is a shame that in the normal science education, we so often fail to convey that important insight.

__________________
Logic is the grammar of truth.

Meaning and absolute certainty are incompatible, and profound meaning and absolute certainty are profoundly incompatible.

The only thing intelligence is capable of is recognizing itself.

The burden is not on me to show that science produces a model that may or may not correspond to some actual that forever lies inaccessible. Speaking of science as if it were in a model/absolute framework, however, follows the same pattern of the picture metaphor in which we draw an analogy for what we say or claim to a picture or painting of an object. The metaphor is fine, but in philosophical discussions I think you can resolve some issues by noting the figurative aspects of the language. We don't have to seriously worry if our theories are literally asymptotically approaching some absolute or not if that is just a figure of speech.

As for the question “Is the scientific method obsolete (because modern research methods don't produce models or underlying mechanisms)?” my answer is: No, it is not obsolete. The scientific method doesn't produce models, strictly speaking, nor does it always reveal an underlying mechanism. Both Newtonian and quantum mechanics succeed quite well without specifying an underlying mechanism.

Philosophies often run parallel to each other. They say some of the same things in different ways. If you are trying to pin me down to a well-known philosophy, it's probably somewhat like later Wittgenstein (Philosophical Investigations) or Gilbert Ryle (Concept of Mind), but really, all the blame lies with me.

In noting metaphorical aspects of what this or that person says, I am not criticizing; I am trying to clarify by offering another way of looking at the matter.

We are not shielded behind models or representations from a reality which is “underlying” or otherwise always just out of reach. Our actions have consequences, so it's not “anything goes.” We are up to our necks in an enveloping reality and must swim to stay afloat. Science, and all branches of learning, teach us how to swim. Swimming, to use a different metaphor than the picture metaphor, is not a model or picture of anything else. You either do it well enough or you don't.

That's all I am saying. Once you acknowledge the figurative aspects of language, and recognize when they have creeped into a philosophical discussion, you can momentarily set such notions aside and look at what people actually do to succeed, to fail, to recovery from failure, to improve, etc.

Look at what is going on here. You act to resolve a problem in the world that you are temporarily engaged in. You ask a serious of questions to prompt suitable feedback from me. There is no model that you amend. Rather, you refine the way you will deal with me, interpret what I say, disagree with me, and so on. The way we interact with each other is changing by the give-and-take of this discussion.

How about this: think of the here and now as part of the larger actual that extends off into the distance. You don't need dualism to say what you want to say. There doesn't have to be a model-reality with a real-reality hidden somewhere behind or underneath it. Science was supposed to have split from the view where we think that behind all the events we see in front of us, there are gods on Mt. Olympus or whatever directing it all. That is, science was supposed to have moved away from occult explanations where the real stuff was hidden underneath or behind the scenes. We don't need such a dualistic view to highlight the fact that science can always improve.

Which of these tuna casserole recipes is closer to the "actual"?

Tuna Casserole Recipe 1
Tuna Casserole Recipe 2

Newton and GR are two recipes or techniques for (among other things) predicting the positions and motions of bodies. Don't think of Newton's theory as just ink markings in a book. Think of a student who has drilled on the subject and then proceeds to calculate for us where to look for a given comet in 90 days time. That student is not moving closer to or farther from anything. He is doing something. It will either work well for him or it won't—for any number of reasons.

Notice that with the approach I am using here, we don't need to speak in terms of model and actual to illustrate that science is rarely, if ever, certain. We can be wrong for many reasons. We might be sloppy or careless. We might make a mistake. The quality of our observations might be poor. Our methods might be untested or not well developed. We might use a formula in inappropriate circumstances.

Suggesting that we are wrong because we possess a model that does not accurately represent reality overlooks all those factors. Blaming scientific failure on a model is an extremely simplistic metaphor. That strategy works to our advantage in general circumstances, so, I am not saying we shouldn't use the term “model” interchangeably with “theory.” But we may need to remind ourselves now and then that it is just a metaphor.

Stated more straightforwardly, there may be some aspects of nature that we never master.

Newton's book does not represent nor stand for anything else. It is a bunch of ink markings on paper. Altering the shapes of the markings does not move it closer to or farther from anything else, nor does it make it a more complete or less complete stand-in for something else.

Except figuratively speaking.

Or that there is more than one way to skin a cat.

I'm going to try to strip out some of the dualism inherent in that:

The engineers don't observe RF energy “through instruments.” They observe the instruments and how they change as they alter the environment. They don't “relate the observed behavior to a concept of an electric field.” They calculate and cut antenna element lengths and configure antenna array geometries to maximize the needle positions on their instruments, to reduce the amount of static relative to signal coming out of the speakers, and so on.

The way they treat antennas and the rest of their RF equipment may be similar to the ways they treat water waves and oscillating springs, but their techniques are not pictures, models, or representations of water waves or anything else.

You start out saying you have no idea if these notions have a close resemblance or not to the underlying reality, and then you say that they must be models of that reality. So far, nobody has really pointed out in this discussion what the model is and what the underlying reality is supposed to be, so it is not clear why we should think the two share a relation of representation.

Briefly, the techniques work as well as they do because they were tested. Good science is good procedure.

What about those times when you bang your toes on the damn coffee table leg?

There is more than one way to skin a cat, but that doesn't mean that cat skinning must then be a model or representation of skinned cats or some underlying skinned cat or whatever.

That all sounds more like philosophy than science.

No one needs to show it, for it is obvious.

Oh, I disagree that it's just a figure of speech. It's an image that illustrates three important facts about science:

1) Scientific knowledge is not the same as truth. If it were, we wouldn't need to revise it and correct it all the time.

2) Scientific theories should be regarded as simplifications of and approximations to the data on which they're based. They are never identical to the data. Therefore, we should not be surprised when they fail to describe the data with 100% accuracy.

3) I noted above that scientific knowledge is permanently subject to revision. But how do scientists determine when it should be revised, what should be revised, and how it should be revised? The answer is that scientific theories do not exist in a vacuum. They are not self-justifying (another reason why they are not the same as truth). There are standards in science that good theories must meet. One such standard is that the theory must be reasonably compatible with observation (though perhaps not with 100% accuracy, as I noted in the previous point).

Each of these three facts shows that there are important dualities in science. Truth on one side, science on the other. The complexity of the data on one side, the simplifications of science on the other. Observation on one side, theory on the other. This is why it makes perfect sense to describe science and scientific theories as models of something else (it doesn't matter that we can't access that something else directly).

Some people may feel uneasy about these dualities. They may long for a simpler, more holistic image, where science is not subject to the flawed judgement of the scientists, but merely proceeds forward with a life of its own, impartial and unhindered, gathering more and more itty bitty little facts until it becomes one with the truth -- like a shopping cart at a supermarket.

The shopping-cart image of science has the appeal of giving the impression that science can do no wrong. Scientists never make any mistakes; they just need further data, sometimes. It's a more comfortable position. But isn't it interesting that many people formed in the hard sciences, such as Ken G, will instinctively reject the shopping-cart view of science?

I would say more: it's telling. Because the shopping-cart image shows a deep misunderstanding of the scientific process. In reality, science is not an additive process that keeps going forward like a train firmly on its tracks, and just gobbles up more and more data. Sometimes, scientists need to throw away what came before, and go back to the drawing board.

I find the picture metaphor much more realistic than the shopping-cart metaphor.

__________________
"A witty saying proves nothing" Voltaire.
"All your bias are belong to us" Ara Pacis.

Joe

This word "model" certainly seems to causing some problems that I'm not entirely sure are fully justified, so would it be worth getting back to basics? The dictionary defines the word as "a simplified description, esp. a mathematical one, of a system or process, to assist calculations and predictions."

I think of the "system" as being our macroscopic reality, so from that perspective, the scientific model is a simplified description of that reality that allows us to understand nature in an objective manner. If we understood everything about nature then that understanding would not be a model, it would be the "system", but is science up to such a feat?(I think not). So if I suggest that science simplifies, then according to the dictionary definition Newton's laws and GR are both a model of the gravitational "system". Now this seems fairly uncontroversial to me, so is it the case that you don't see science as simplifying anything about our reality, or is it solely your dislike of the word "model" seeming to invoke a notion of underlying or distant reality as being distinct from a simplified scientific representation?

Our science at the quantum level takes the form of predictive observations, not events - there is no "particle" prior to a measurement/observation. The predicted observation of a particle is clearly a simplified description of "something" within the "complex system" that consists of us as observers and a reality that is mind independent and inaccessible. That we are forced to acknowledge an element within the "system" that is outside of our knowledge, reinforces (for me) the dictionary definition of a model as a simplified representation since we have no possibility of ever reaching this element of mind independent reality. Again, in this context, the use of the term "model" to me seems fairly uncontroversial.

I'm trying to avoid repetition from my posts, but I apologize for seemingly going over the same ground, I am having some difficulty in seeing where the problem with the use of the term model lies, and where exactly you are coming from (and why). Perhaps if we try and clarify things from basics, it may help.

Incidentally, I am reading a book at the moment on Maxwell and there is a chapter entitled "spinning cells". It seems that Maxwell formulated a mechanical model to represent current flow, magnetic and electrostatic force and electromagnetic waves consisting of cells and wheels. He also derived the ratio of electrostatic and electromagnetic units of electric charge to give c from this model.

This is what Maxwell said of the model: (from "The life of James Clerk Maxwell" by Basil Mahon)

"The conception of a particle having its motion connected with that of a vortex by perfect rolling contact may appear somewhat awkward. I do not bring it forward as a mode of connexion existing in nature, or even as that which I would willingly assent to as an electrical hypothesis. It is however, a mode of connexion which is mechanically conceivable, and easily investigated, and it serves to bring out the actual mechanical connexions between the known electromagnetic phenomena; so that I venture to say that any one who understands the provisional and temporary nature of this hypothesis, will find himself rather helped than hindered by it in his search after the true interpretation of the phenomena."

How would you see this in terms of the discussion? To me it seems that Maxwell obviously knew that electromagnetic and electrostatic fields were not actually microscopic cells and wheels, but he saw it as a means of representing a reality that he knew was completely different in nature to the model. There is implied a clear distinction between model and reality, and I can't help thinking that we could pretty much repeat Maxwell's quote in a more modern context say when (for example) talking about "travelling photons between a source and sink in vacuum)".

Hmm - correlation replacing theoretical constructs. It's interesting, but isn't equating correlation with cause, or ignoring cause altogether what got us magical thinking in the first place? Maybe the new magic will work a bit better than the old, being based on mountains of data, rather than a few scattered points mangled by confirmation bias - but at the end of the day, doesn't it leave you just as ignorant?

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http://amssolarempire.blogspot.com

I think Hume made a pretty good philosophical (yet logical) argument that there can be no fundamental difference between correlation and cause. The effort to attribute cause that is more than strict correlation is simply its own form of magical thinking, albeit a more successful one.

Yes. Unfortunately, we have no other option. Attempts to understand "why" things are as they are does nothing but generate useful pictures that help us isolate unifying elements of the correlations we observe. We are seeking two elements then: unification and reliability. What you are calling magical thinking is strong on the former, correlation analysis is strong on the latter, and good science tries to find the best of both worlds. Who was it that said magic is indistinguishable from advanced technology? (They said it the other way around, but I like it better this way.)

__________________
Logic is the grammar of truth.

Meaning and absolute certainty are incompatible, and profound meaning and absolute certainty are profoundly incompatible.

The only thing intelligence is capable of is recognizing itself.

There it is....efficacy. I liked it the first time you used it long ago. It kicks!

Very nice. I like your use of "interfacing" since it implies a functional connect, which is not easily seen in most pedagogical pictoral view; pictures lack efficacy. [Did I mention I like this word?]

Yes. Using the Copernican model that was mentioned, at least in the 16th and 17th centuries, this model thrived on the use of Occam's Razor, contrary to what I used to understand of it. It was simple and elegant with the way it addressed retrograde and orbital periods. This "interface" was thought to have fewer wires, but later, more wires were needed to match the accuracy of Ptolemy's model because both were stuck on the circular orbit idea. [Too bad Galileo did not jump into Kepler's ellipses model. Perhaps, the additional distaste this brought against Aristotle outweighed the efficacy benefit.] Nevertheless, the Copernican model ran its wires in a very orderly and understandable way. Not until Newton's gravity model did the Copernican efficacy become realized.

Another very nice thread, folks.

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Lighten up! This is a stellar board! Author: duh.

"The mean of five measures each of which is not worth a dang (sinc), has a maximum value of only five dangs (sinc)". Heber Curtis

"(sinc)" - spelling is not correct (in its orginal form) :)

That's a point that I think is not widely appreciated. The main problem there, I believe, is that Copernicus always gets compared to Ptolemy, but Ptolemy's model was wrong for a host of other reasons that don't necessarily have anything to do with its core differences from Copernicus' ideas. The crucial problems with Ptolemy's model that Copernicus saves you from is that Ptolemy's includes incorrect notions about motion, inertia, gravity, and most importantly, the distance to the stars. Once you correct them, you find that there is nothing special about the motion of the Earth, which was really the core error in the Ptolemy model. But we tend to put too much stress on other details of that model that are easily disproved, like how the phases of Venus show that Venus goes around the Sun. The first telescope would have disproven Ptolemy even if there had been no Copernicus-- that's not really the crucial issue.

A more interesting comparision is between Copernicus and the model of Tycho Brahe, because Tycho made all the same errors the Greeks did about inertia, motion, gravity, and the distance to the stars, but he had better data than Ptolemy, so he knew Ptolemy's model didn't work. So he was led to the idea that all the other planets orbit the Sun, not the Earth, but he still had to have the Earth be stationary so he had to make the Sun orbit the Earth! This is not nearly the "paper tiger" that is Ptolemy's model, because it is actually much more like Copernicus' model, it just focuses attention on that most key of questions: is the motion of the Earth special in some way?

So it does require Newton's laws to give us the answer to this, nothing less will really suffice. Newton's laws unify our understanding so completely that they leave no room for the sterile idea that the Earth's motion is special, and that's what selects Copernicus over Tycho. Note I do not say we know whether the Earth orbits the Sun or the Sun orbits the Earth, because general relativity tells us that this is a meaningless question-- it is how we choose to look at it. But what we can say is that there is nothing special about the motion of the Earth, relative to other planets, that derives in anything but the fact that we are here and can therefore choose to treat its motion as special for purely subjective reasons. This is the real culmination of that debate, once the gross flaws in the Ptolemy model are dispensed with via even the most rudimentary telescopic observations, and once the Greek (and Tycho's) misconceptions about motion and gravity are corrected.

Reaching this destination required Galileo's notions about inertia, Newton's notions about the sources and nature of forces, and even to some extent Einstein's notions about the arbitrariness of reference frames. What will be the next chapter?

__________________
Logic is the grammar of truth.

Meaning and absolute certainty are incompatible, and profound meaning and absolute certainty are profoundly incompatible.

The only thing intelligence is capable of is recognizing itself.

Indeed, Ptolemy built upon Aristotle's views, where the Earth was the logical center of the universe. [Aquinas then added rebar to give it concreteness when he anchored it into theology, which was going adrift.]

Yes, it was the introduction of the Copernican model that caused him to rethink Ptolemy's. I suspect he was taken by the persuasiveness and elegance presented in de Revolutionibus, again an Ockham's Razor view, no doubt.

It is interesting how Tycho combined the benefits of both models into his third model that brought the tidal change for the Jesuit scholars, who quickly adopted it. It seems his math skills were not exceptional, however, since he had to rely on Kepler to put his data to real use. [Kepler knew this, too, and refused to be an underling to Tycho.]

Agreed, though I suppose we could argue that had Kepler's laws been understood by others, with the right dash or two of Ockham, then Copernicus would have been more respected. Yet, interestingly enough, GR is supportive of either the Tychonic or Copernican model, though I see this as a somewhat mathematical approach that is effective for launching rockets, for example.

I see you had beat me to it. However, I think we disagree here, just maybe. A causal foundation to any model has to be superior to one that offers little or no causal explanation if both models give the same predictions. This GR question is still quite foggy for me since both Newton and GR do offer a causal explanation for each: a gravitational field and spacetime warpage proportionate to mass, respectively. [Though my view of GR must be naive since we are still trying to snag some gravitons.]

[I appreciate your view that it is the Earth's motion that is not special, as I doubt Copernicus would agree with the Copernican principle used to apply to Earth itself.]

I don't know, but it will probably add new dimensions on how we look at things. I'll probably try to string along, in a flailing kind of way.

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Lighten up! This is a stellar board! Author: duh.

"The mean of five measures each of which is not worth a dang (sinc), has a maximum value of only five dangs (sinc)". Heber Curtis

"(sinc)" - spelling is not correct (in its orginal form) :)

Quote:
The funny thing is that the "physical" model and theory builders do not see the funny side of this. Decades ago Box and Jenkins demonstrated that in economics, all the theories and models and using 100 time series to forecast just one of interest could not compete with a "dumb" model that knew nothing about economics and that used only the series itself. I don't think that has stopped economic modeling, but it has largely obsoleted it.

Much of the stuff done as physics and nearly all of cosmology fits into the same category. You don't need the "physical model" to get the best results. Modeling is just for us to be able to get new ideas, it doesn't help with the results.

I think you are asking the key questions, but there may be one thing you haven't recognized, which is that GR largely removes the issue of causality from all levels of motion other than the most deeply geometric. In other words, in GR we only ask what is "causing" the curvature of spacetime-- the motion within that spacetime is 100% purely a question of reference frame. So there is a spacetime with all the right geometry (caused by the Sun's gravity) in which the Earth is stationary and the Sun orbits the Earth. In that spacetime, the motion of the Sun derives from the coordinate chart we have chosen to give values to the quantities that describe the positions of things-- which is completely arbitrary once the geometry is fixed.

You can think of this like taking your favorite vase from your living room, and deciding on a way to specify quantitatively the location of every point on the vase. You can put a "coordinate chart" on the vase to do that, and you can do the chart any way you like. However, once done, if you ask questions like how tired does an ant get crawling between various points, the answer will depend on some things that are special to your coordinates, and other things that are special to the shape of the vase. The former is arbitrary, the latter is the only thing in need of a "cause" (the shape of the vase).

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Logic is the grammar of truth.

Meaning and absolute certainty are incompatible, and profound meaning and absolute certainty are profoundly incompatible.

The only thing intelligence is capable of is recognizing itself.

Yeah, but what causes the Sun's gravity?

Exactly. Causality is itself a model that gets folded into other models for all the same reasons that we make models in the first place: to unify experience.

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Logic is the grammar of truth.

Meaning and absolute certainty are incompatible, and profound meaning and absolute certainty are profoundly incompatible.

The only thing intelligence is capable of is recognizing itself.

Sorry to bump a (now) old post in this thread, but I'm late to the party ...(emphasis added)

I don't know what "astronomy meetings" you're referring to Ken G, but at the very least I think you are missing out on what happens when everyone gets back to the lab/institute/cubicle/whatever.

I mean, if that were all there was, where would ideas for new observations come from? After all, astronomers don't use their zippy new equipment to simply get yet another spectrum of Vega with an x-fold improvement in resolution (to take a ridiculous example)!

But perhaps I misunderstand what you were saying here ...

Ok, but your parenthetic(the Sun's gravity) is foundational to how the various coordinate systems will look. Adjusting the mass, I assume, will change either the coordinate system itself or the coordinate results of motion; cause and effect, in effect.

You would pick ants. But, yes, that makes sense to me as I see the coordinate issue a math construct and not an interface; a wiring diagram but not the wires that actually interface with that reality beyond. It is the wires that have the juice.

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Lighten up! This is a stellar board! Author: duh.

"The mean of five measures each of which is not worth a dang (sinc), has a maximum value of only five dangs (sinc)". Heber Curtis

"(sinc)" - spelling is not correct (in its orginal form) :)

I think you see what I'm saying, but you are choosing to see the glass as half full while I see it as half empty. "Black box" simulations are like fishing nets, and the bigger the net the better the chance of "catching the fish", i.e, including the key physics that describes some astronomical observation. However, they also have the (large) disadvantage that you only know the "fish" is in there somewhere-- they don't tell you which fish was the one you were trying to find, without a lot of additional and painstaking analysis that in my experience rarely actually happens.

Indeed, I see it rarely enough that I take notice when I do see it (it does happen, of course). So that could be improved-- it turns out the skill to create a huge simulation is often quite a bit different than the skill to "boil one down" into what "really happened". It is the latter skill that I see as more and more lacking, whereas decades ago it was much more prevalent (largely because the black boxes had to be much simpler). I'm not saying no one combines those skills-- some do, and admirably at that. It's just not the typical theory or observational talk that does.

As for stimulating future observations, in my experience observations are more often technology driven than theory driven. The CMB was not found because someone said "look for it" (though it almost was, it's true), it was found because the technology to see it was developed. Ditto for quasars, ditto for pulsars, ditto for gamma ray bursts. The theory does often say "you'll need X spatial and Y spectral resolution to see Z effect", but again those can all be callibrated by black box simulations once the discovery of the effect has occured. We do often see "cartoon" level descriptions of "what happened", but that's not what I'm talking about either, as the cartoons don't really tell you much (they won't usually give you factor-2 sorts of estimates, for example). What is (somewhat) lacking is descriptions like "although the full physics that went into the simulation was Y, it turns out that if you just focus on the simple effect X, you get a result whose gross level of accuracy is not that far out of step with the other gross idealizations that are being applied to the question." That is loosely how I would define "understanding".

I should mention, however, that some problems do indeed have a fairly reliable level of precision in the calculations, like stellar interior models. So when the neutrinos come out wrong to a factor of 2 or 3, or if the model won't supernova when it is supposed to, those problems may be taken seriously and lead to new discoveries that can only come from detailed "kitchen sink" simulations (the fishing net, again). So such simulations have their place. I would say they are pretty much all you see, however. (Welcome back Nereid, long time no see!)

__________________
Logic is the grammar of truth.

Meaning and absolute certainty are incompatible, and profound meaning and absolute certainty are profoundly incompatible.

The only thing intelligence is capable of is recognizing itself.

That seems like no more than handwaving. What evidence do you have of what you're saying?

I don't mean the economic stuff, which I won't comment on, but your claims about physics and cosmology.

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"A witty saying proves nothing" Voltaire.
"All your bias are belong to us" Ara Pacis.

I would say it is foundational to the shape of the vase-- but the coordinate systems can still look very different. For example, issues like which is orbiting which are entirely coordinate dependent issues, and GR tells you how to make any coordinate system function. They may result in awkward or unphysical seeming boundary conditions, but who can say what the "right" boundary conditions are? That's pretty much the road that leads to Mach, which is where the GR journey all started.
What makes a coordinate system useful for doing physics is having a mapping from the coordinates to distances (a metric). Different looking coordinates can have different looking metrics yet still be the same (i.e., they apply to the same vase). The "coordinate invariant" properties will be the only ones that "nature itself knows", so that doesn't include which object is orbiting which. However, given the way we read extra things into the situation, it seems the more "objective" perspective to say that the Earth orbits the Sun, as it shows that the Earth does not need to be stationary, and we do not need to invoke "coordinate forces" (like centrifugal force) to understand what is happening. So on that basis some claim that this is the "truth" of the matter.

__________________
Logic is the grammar of truth.

Meaning and absolute certainty are incompatible, and profound meaning and absolute certainty are profoundly incompatible.

The only thing intelligence is capable of is recognizing itself.

Yes, and my wording failed my intent. What I meant was that regardless of which maping method you like to use for the vase, if you change the vase, either you will find the new coordinates of the vase will be different on the map or another map method will be needed. The point is to focus on the importance of a changing vase as a causal action.

Yes, and I think the difference in the spacetime effects that corresponds to the body's gravity is a sure sign as to which is the more likely correct view as to which object is orbiting which, even though the GR math (if you allow this abuse) allows either.

This is better seen, I think, when we regress to the antipodal apples scenario where apples on opposite ends of the globe fall simultaneously toward the ground so a fixed Earth model (relative to the apples at least) is superior than any other model for human semi-reality consumption.

__________________
Lighten up! This is a stellar board! Author: duh.

"The mean of five measures each of which is not worth a dang (sinc), has a maximum value of only five dangs (sinc)". Heber Curtis

"(sinc)" - spelling is not correct (in its orginal form) :)