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Dave W.
Info Junkie
USA
26022 Posts |
 Posted - 11/01/2011 : 20:18:50 [Permalink]
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Originally posted by Sebastian
I'm getting a strong sense of a lack of clear thinking from some of you people. Let's examine some of Dave W's comments.
1. | And what's wrong with the indirect evidence that we have in hand, which has been tested, verified, examined, deconstructed and re-tested all over again and has not yet met a test which falsified it? |
It seems that Dave is confused about the difference between direct and indirect evidence. Indirect evidence is an inference or implication. |
Sebastian, you are pontificating about a subject you clearly do not understand. All scientific theories are inferences. Every one of them, even the ones you think are correct. Since a theory cannot be "indirect evidence," you obviously don't understand the meaning of the word "inference."
Evidence is never itself an inference (either direct or indirect), it is an observation. If the observation matches a prediction of a theory, then it is supporting evidence. If not, then it is falsifying evidence.
There are no scientifically rigorous definitions of "direct" or "indirect" evidence, because when one boils everything down, almost all (if not all) evidence is indirect in some way. Measurements depend upon the assumption that our measuring devices are accurate, for example.
To illustrate the point, is an anemometer reading above zero direct or indirect evidence for the presence of wind? Is seeing leaves flap around on trees direct or indirect evidence for the presence of wind? If the latter answer is different from the former, why?| By its very nature it cannot be verified or falsified except in a fictitious sense, as in the context of a novel where each character behaves in a credible manner. |
This is laughable. All the evidence we have for electrons is indirect, yet atomic theory has been verified over and over again.2. In response to my statement: "Even after all these processes have been carried out, sometimes over several generations, we can still be wrong."
Dave W replies, | Which, if taken to its extreme, suggests that we should never settle on anything, not even for an instant. We might find out we were wrong later, after all. |
Confusion again.There is always a good reason to settle on something (such as a well-tested theory) if it continues to work flawlessly... |
It could still be wrong.| ...and is instrumental in the production of the goods and service which we use for our survival and activities on this planet. |
That is in no way a basis for measuring the correctness of a scientific theory. Practicality in science isn't the same as practicality on the streets.| It's only when theories are found to be inadequate or not sufficiently accurate for certain purposes that we have to rethink them. Newtonian Mechanics is still valid for many tasks on the surface of our planet involving relatively short distances. |
And yet, General Relativity is more accurate.| And Dark Matter is a practical, functioning solution to many questions about the universe. To paraphrase you, IT WORKS. |
Just like the concept of God, or an intelligent creator works? Just as a character in a novel works? It seems we have a different understanding of the meaning of practical. |
No, it seems that you think that indirect evidence isn't evidence at all, and you don't have a clue as to what an inference is. One cannot make predictions about the behavior of the universe based on "god" or "intelligent design." One can make predictions of what will be found if Dark Matter theory is correct. Several of those predictions have been verified, providing positive evidence for Dark Matter's existence, even if we have no direct evidence of its composition (although we do have direct evidence for several things it cannot be).It's seems that Dr. Mabuse is just as confused as Dave W.
When push come to shove, you're making an argument from incredulity. While agreeing with the point that dark matter exist because we can measure its effects.
I think you need to go back and re-think your position on the matter. |
Firstly, all questioning begins with some degree of incredulity. When the question is satisfactorily answered the incredulity ceases. |
Your only argument against Dark Matter is that you personally think there's too much of it. That's neither an objective question, nor is it strictly falsifiable. It is based on no evidence, just your incredulity.| My position is clear. That which exists can be measured or detected. |
So demonstrate that Dark Matter cannot be measured or detected. Show all the scientists who've measured and detected Dark Matter to be wrong.| That which cannot and/or has not been measured or detected cannot be claimed to exist, although one may speculate that it may exist, which is the case with Dark matter and energy. |
Asserting something doesn't make it true. You need to support your case regarding Dark Matter with actual evidence and argument. You've done neither to date.| When a group of scientists have to invent the existence of an absolutely enormous quantity of totally invisible matter in order to preserve its current theories... |
This is a reversal of reality. The proposition of Dark Matter was a change to existing theories.| ...then warning bells should be ringing, especially on a skeptic site such as this. This is a skeptic site, isn't it? |
And now more ad hominem attacks.  |
- Dave W. (Private Msg, EMail)
Evidently, I rock!
Why not question something for a change?
Visit Dave's Psoriasis Info, too. |
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Dave W.
Info Junkie
USA
26022 Posts |
Posted - 11/01/2011 : 20:29:58 [Permalink]
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Originally posted by Sebastian
The confusion deepens. What is Tim Thompson trying to say in the following quote?| The "who" you question above is the scientific community itself. The original papers & reports present the scientific arguments, including the limitations of technology, and they are open to examination by the community. It is not a subjective process; the elements of science & technology are objective, constitute valid, objective limits on observation. If you know that object X, whatever it is, should lie within the bounds of detectability established by technology, and you don't see it, then you can confidently assert that object X in fact is not there to see. It's reasonable, it's objective, and it is wholly valid science. |
He seems to be saying that it is reasonable, objective and wholly valid science to assert that Dark Matter does not exist. |
No, your memory is faulty. He was telling you how it is possible to prove a negative within science.| However, I also believe in lateral thinking, outside the box. |
To think outside the box, one must first understand what is in the box. You do not.| I'm certainly not excluding the notion that 95% of our universe is currently invisible by its very nature. |
You called it "mythical." Are you retracting that characterization?| I just think the notion is 'a bit over the top', to put it mildly. |
Thankfully, reality doesn't care what you think. |
- Dave W. (Private Msg, EMail)
Evidently, I rock!
Why not question something for a change?
Visit Dave's Psoriasis Info, too. |
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Cuneiformist
The Imperfectionist
USA
4955 Posts |
Posted - 11/03/2011 : 09:32:57 [Permalink]
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Originally posted by Sebastian
The confusion deepens. What is Tim Thompson trying to say in the following quote?
| The "who" you question above is the scientific community itself. The original papers & reports present the scientific arguments, including the limitations of technology, and they are open to examination by the community. It is not a subjective process; the elements of science & technology are objective, constitute valid, objective limits on observation. If you know that object X, whatever it is, should lie within the bounds of detectability established by technology, and you don't see it, then you can confidently assert that object X in fact is not there to see. It's reasonable, it's objective, and it is wholly valid science. |
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Where did you get this quote from? It's not turning up at all in Google. |
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Dave W.
Info Junkie
USA
26022 Posts |
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Cuneiformist
The Imperfectionist
USA
4955 Posts |
Posted - 11/03/2011 : 10:19:10 [Permalink]
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Originally posted by Sebastian
My position is clear. That which exists can be measured or detected. That which cannot and/or has not been measured or detected cannot be claimed to exist, although one may speculate that it may exist, which is the case with Dark matter and energy.
When a group of scientists have to invent the existence of an absolutely enormous quantity of totally invisible matter in order to preserve its current theories, then warning bells should be ringing, especially on a skeptic site such as this. This is a skeptic site, isn't it? |
What's there to be skeptical about? Either way, we have to deal with a major problem: gravity-- a force we understand quite well-- doesn't behave as we expect when we look at galaxy rotation. So either (a) we posit that something is wrong with our understanding of gravity, or (b) our understanding of gravity is fine, but there's something we don't understand about matter (or a type of matter).
Given how robust our understanding of gravity is, scientists have tended towards option (b)-- namely that there's a type of matter that doesn't interact with electromagnetic radiation as we might expect.
Subsequent experiments have seemed to bear this out (such as through gravitational lensing) so that people are rather secure in positing a type of "dark matter" even if we can't yet directly observe it.
Your objection seems to be "since we can't see it, then we're crazy to posit that it exists!" which, given the history of science, is a rather juvenile position to hold. (For instance, the neutron was posited to exit in 1920, but wasn't actually observed until 1930.) So, sure-- it would be nice to observe things. But just because we can't see "dark matter" directly doesn't mean we should dismiss it. The other option is to totally revise our understanding of gravity, and you have to imagine that if that were a realistic prospect, someone would already be working on it. That we haven't heard much about entirely new approaches to gravity suggests that dark matter is the more viable solution to the observed problems. |
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Cuneiformist
The Imperfectionist
USA
4955 Posts |
Posted - 11/03/2011 : 10:21:51 [Permalink]
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Originally posted by Dave W.
It's in the middle of this post, Cune.
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Ah. So Tim Thompson is an actual SFN guy who worked at JPL? And he plays chess at the near-Expert level? Too bad he's not around more often! |
| Edited by - Cuneiformist on 11/03/2011 10:22:33 |
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Tim Thompson
New Member
USA
36 Posts |
 Posted - 11/03/2011 : 11:15:57 [Permalink]
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Originally posted by Sebastian
The confusion deepens. What is Tim Thompson trying to say in the following quote?
Originally posted by Tim Thompson
The "who" you question above is the scientific community itself. The original papers & reports present the scientific arguments, including the limitations of technology, and they are open to examination by the community. It is not a subjective process; the elements of science & technology are objective, constitute valid, objective limits on observation. If you know that object X, whatever it is, should lie within the bounds of detectability established by technology, and you don't see it, then you can confidently assert that object X in fact is not there to see. It's reasonable, it's objective, and it is wholly valid science.
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He seems to be saying that it is reasonable, objective and wholly valid science to assert that Dark Matter does not exist. If so, I would agree with him on that point.
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That is certainly not what I meant, and I should think that would be obvious from the context of the conversation (see the post from which this quote is taken and my earlier posts on 9/17 & on 9/24). I don't see how you can be confused to the point of asking "What is Tim Thompson trying to say ...", when it strikes me as quite obvious.
Quite simply, we know that the old standard theory that tells us how the universe should behave is incompatible with our observations of how the universe actually does behave. This leads us directly to the conclusion that either (1) there is additional unseen matter in the universe, or (2) we are using an erroneous law of gravity to describe the motion of the matter that we do see (or perhaps some combination of both). There are productive & active scientific groups investigating both possibilities in the open literature.
It is my contention, and the majority opinion of the relevant scientific community, that the evidence thus far favors case (1) over case (2). Investigations into the form of the law of gravity have produced interesting results to be sure, but the implication is always that changing the law of gravity will solve one problem for a specific system, but not for systems in general; case (2) creates more new problems than it solves old problems. On the other hand, case (1) works universally for all systems and does not create new problems as does case (2). So naturally case (1) is favored.
In the context of case (1), the additional unseen matter is either ordinary, baryonic matter, or it is exotic non-baryonic matter (or perhaps some combination of both). The advent of astronomical capabilities that allow us too look deeper to see intrinsically dimmer objects and see across the entire electromagnetic spectrum have significantly affected the search for this unseen "dark matter".
Now remember my previous comments:
Originally posted by Tim Thompson
When Zwicky first introduced the problem of "missing mass" (Zwicky, 1933; Zwicky, 1937; the latter translation into English was the first time many astronomers became aware of the issue) he had no reason to believe it was not ordinary matter; gas, dark clouds of dust, dim stars, planets & etc. And there is no single moment when suddenly & without warning astronomers exclaimed "it must be non-baryonic dark matter". It just slowly dawned on astronomers as they continued to look and did not see. In this case, the context was set by technology. If you look for something and do not see it, even though you know it lies well within the capabilities of your technology, then the failure to detect it is significant, and increases in significance as time & technology advance with continuing invisibility of that which should be seen. The advent of radio & infrared astronomy is particularly damaging to baryonic dark matter, since cooler stars & especially clouds of dust & gas will stand out clearly at theses wavelengths, where they would be truly invisible to Zwicky. Likewise, X-ray astronomy reveals hot gas & low-mass stars (the latter, being fully convective, are somewhat more prone to flare than solar-type stars and so become evident as X-ray flare sources). In the case of our own Milky Way, specific searches for low mass stars have clearly demonstrated that they cannot be the ultimate source of dark matter (e.g., Hubble Space Telescope, 1994).
Inference from observation is a crucial element of the scientific process and should not be discounted as "merely hypothetical". Not all hypotheses are created equal nor should they all be considered on equal footing. In this case, the hypotheses of dark matter & dark energy are both supported by significant observational data. If astrophysical dark matter is baryonic, then where & what is it and how does one explain that it is not visible to instruments which have the capability to see it? That is just as serious an issue as the fact that non-baryonic dark matter has not been directly detected, and in my mind a more serious issue in fact, which gives significant weight to the dark matter hypothesis.
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We now know that if the dark matter we seek by astronomical observation were in fact made of ordinary baryonic matter, we would have seen it. We also know that we have not seen it. Ergo, simple logic, the dark matter we seek by astronomical observation must not be made of ordinary baryonic matter. It must be made of exotic, non-baryonic matter. I fail to see why this should be a severe mental exercise.
I agree. I also assert that the scientific community is actively doing exactly that. No idea is being excluded, all ideas are being investigated. The explanation adopted as a consensus, or majority opinion, in the scientific community, is as a matter of fact the best and most effective explanation. If you think you have a better and more effective explanation, then let's have it.
Originally posted by Sebastian
I'm certainly not excluding the notion that 95% of our universe is currently invisible by its very nature. In fact I'm giving the idea a fair amount of publicity in this thread. I just think the notion is 'a bit over the top', to put it mildly. I think I could find more reason to believe in Intelligent Design. But I could be wrong.
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I think you are definitely wrong. Why is the notion "over the top"? Remember, we are dealing here with practical empirical science. Now we all understand that real science is done by real scientists, and while "science" may exist as an ideal construction, real scientists are far from ideal and so the practical science that they produce is also not necessarily ideal. Scientists may start with feelings, hunches, wild-ass-guesses or dreams. But that is where they start, not where they stop. Your hunch that it is an "over the top" notion means nothing to me, nor to the world of practical science. If you have a specific reason, based on a knowledge of the observational methodology, or the existing data, by which you can support an assertion that the idea is "over the top", then let's have it. Otherwise, this entire conversation really does not amount to anything other then idle gossip. |
The point of philosophy is to start with something so simple as not to seem worth stating, and to end with something so paradoxical that no one will believe it. -- Bertrand Russell |
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Sebastian
New Member
44 Posts |
Posted - 11/03/2011 : 18:52:05 [Permalink]
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| That is certainly not what I meant, and I should think that would be obvious from the context of the conversation (see the post from which this quote is taken and my earlier posts on 9/17 & on 9/24). I don't see how you can be confused to the point of asking "What is Tim Thompson trying to say ...", when it strikes me as quite obvious. |
There's no confusion on my part, Tim, that I'm aware of. If a statement is true, it's true whether or not the statement is in response to a question from one particular person, or from another particular person, or in response to no question at all, unless of course you're following the logic espoused by Dave W who seems to think that reality doesn't care what I think in particular, but by implication reality does care what certain other individuals might think.
| Quite simply, we know that the old standard theory that tells us how the universe should behave is incompatible with our observations of how the universe actually does behave. This leads us directly to the conclusion that either (1) there is additional unseen matter in the universe, or (2) we are using an erroneous law of gravity to describe the motion of the matter that we do see (or perhaps some combination of both). There are productive & active scientific groups investigating both possibilities in the open literature. |
I see no confusion in that statement, Tim. It seems a balanced summary of the situation.
| I think you are definitely wrong. Why is the notion "over the top"? Remember, we are dealing here with practical empirical science. Now we all understand that real science is done by real scientists, and while "science" may exist as an ideal construction, real scientists are far from ideal and so the practical science that they produce is also not necessarily ideal. Scientists may start with feelings, hunches, wild-ass-guesses or dreams. But that is where they start, not where they stop. Your hunch that it is an "over the top" notion means nothing to me, nor to the world of practical science. If you have a specific reason, based on a knowledge of the observational methodology, or the existing data, by which you can support an assertion that the idea is "over the top", then let's have it. Otherwise, this entire conversation really does not amount to anything other then idle gossip. |
Tim, whatever the state of knowledge of any individual, whether he be an expert in a particular field or a generalist or a layman or a philosopher, he can only approach or understand any subject or topic from the basis of what he already knows.
What is already known (by anyone, expert or layperson) is often simply wrong or at best inaccurate. Experts are not immune to being wrong, neither is a consensus of expert opinion immune from being wrong.
I've been pilloried in this thread for my incredulity and amazement that a group of experts in cosmology should attempt to reinforce their theories on gravity through the invention of truly massive amounts of invisible matter and undetectable energy.
Why should I be incredulous? Because my general understanding from readings in the history of science is that our theories of gravity have always been problematical. Correct me if I'm wrong.
Galileo puzzled over the fact that light objects seem to fall as fast as heavy objects.
Newton failed to adequately explain why the universe would not collapse upon itself as a result of his laws of gravity.
Einstein initially fell into the trap of believing the universe is static, until evidence suggested it was expanding, resulting in a modification of his theory of relativity.
The gravitational force itself has never been isolated. Einstein spent the latter part of his career trying to find a theory that united all the basic forces, gravitation, strong interaction, weak interaction, and electromagnetism, but failed. So has everyone else, as far as I know.
Whilst Einstein's theory of relativity admitted the possibility of Black Holes, Einstein personally didn't believe they could exist. As I understand, but correct me if I'm wrong, there are currently serious problems using Einstein's theories and equations in describing the behaviour at the Event Horizon of Black Holes.
It's within this context of a history of problems with our theories of gravity, plus the fact that the force of gravity itself, in a fashion, is as invisible as the proposed Dark Matter & Energy, that causes alarm bells to ring.
To my mind, to put it simply and perhaps crudely, it's as though a group of scientists is saying, "Heck! We don't even know what gravity is, so let's support our inadequate theories of gravity, when we have a serious problem a billion light years away, by inventing a much more elusive force called Dark Energy."
Well I never! 
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Cuneiformist
The Imperfectionist
USA
4955 Posts |
Posted - 11/03/2011 : 19:31:50 [Permalink]
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So your basic argument seems to be: since previous scholars got some aspect of gravity wrong, then current scholars must also have some aspect of gravity wrong, and this whole "dark matter" thing is a canard invented to make up for the fact that current researchers haven't figured out how to properly address the gravity problem.
Is this correct? |
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Dave W.
Info Junkie
USA
26022 Posts |
Posted - 11/03/2011 : 19:36:25 [Permalink]
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Originally posted by Sebastian
...unless of course you're following the logic espoused by Dave W who seems to think that reality doesn't care what I think in particular, but by implication reality does care what certain other individuals might think. |
A magnificently false implication. Reality doesn't give a damn what anyone thinks, me included. And how well our models fit our many and varied observations is an objective matter, and so your feelings (or anyone else's) don't factor into the equations at all.| I've been pilloried in this thread for my incredulity and amazement that a group of experts in cosmology should attempt to reinforce their theories on gravity through the invention of truly massive amounts of invisible matter and undetectable energy. |
You've been pilloried because that's not what the cosmologists did. You have attributed motivations to cosmologists that the historical evidence demonstrates they did not and do not have.| Why should I be incredulous? Because my general understanding from readings in the history of science is that our theories of gravity have always been problematical. Correct me if I'm wrong. |
No, you're incredulous about a straw man you've built.| It's within this context of a history of problems with our theories of gravity, plus the fact that the force of gravity itself, in a fashion, is as invisible as the proposed Dark Matter & Energy, that causes alarm bells to ring. |
Only because you're ignoring other context. Like the fact that despite General Relativity failing inside black holes, it works awesomely well outside black holes, and nobody is suggesting that the phenomena we see which is being attributed to Dark Matter is the result of the gravitational action of black holes.
But if you're going to suggest that our best theory of gravity is wrong, you'll have to suggest a replacement which models all of the varied phenomena that we see more accurately than our current models. MOND doesn't do that. Even Hajdukovic plainly stated (in the article you referenced) that his own idea doesn't fit the data as well as Dark Matter does.| To my mind, to put it simply and perhaps crudely, it's as though a group of scientists is saying, "Heck! We don't even know what gravity is, so let's support our inadequate theories of gravity, when we have a serious problem a billion light years away, by inventing a much more elusive force called Dark Energy." |
To your mind, science must be something other than simply descriptive of what we see. It just doesn't matter what "gravity" or "dark energy" really is, because our scientific theories about these things are just descriptions of the phenomena we observe. At the end of the day, we don't know what anything is, we just slap labels on what we see and try to figure out how it behaves.
And right now, cosmological objects we can see and measure appear to be following a set of behaviors which are currently best modeled (thanks to many experimental results) as if they are caused by a whole lot of otherwise invisible mass and energy.
But you, Sebastian, want to ignore all that hard data in favor of your personal incredulity, your misunderstanding of scientific terms and your childish refusal to acknowledge your failures. |
- Dave W. (Private Msg, EMail)
Evidently, I rock!
Why not question something for a change?
Visit Dave's Psoriasis Info, too. |
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Sebastian
New Member
44 Posts |
Posted - 11/03/2011 : 22:30:51 [Permalink]
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Dave W in his recent posts has provided a wealth of fallacious material we can all learn from. Thanks Dave for the examples. Let's examine them.
1. | Sebastian, you are pontificating about a subject you clearly do not understand. |
This is a typical defense used by someone who doesn't himself understand. Rather than help the poor person whom he claims doesn't understand, by providing useful and reliable information to clarify the matter, the attacker attempts to shield himself from his own ignorance by projecting his ignorance upon the other.
One comes across similar responses frequently on internet forums. They tend to take the general form of ad hominem attacks, such as, "You're an idiot. You haven't a clue. What would you know? 10,000 experts can't be wrong. You're a denialist in the same category as those who denied the holocaust, etc etc."
2. | All the evidence we have for electrons is indirect, yet atomic theory has been verified over and over again. |
Dave really has a problem here. He seems to think that because one cannot hold an electron in the palm of one's hand and actually see it using one's eye balls, it's existence is in doubt.
When Dave takes a photo with his digital camera, perhaps he's equally doubtful that photons exist. Perhaps he thinks that digital images appear through magic. Perhaps he thinks that the flow of electricity has nothing to do with electrons and that we just built power stations and tranformers through a process of trial and error which just happened to result in electricity.
3. | No, it seems that you think that indirect evidence isn't evidence at all, and you don't have a clue as to what an inference is. |
Here we have an example of a complete misreading of what I've written so far, plus a repetition of the first point I made, ie."...you don't have a clue.."
It is surely obvious that indirect evidence is inconclusive until it becomes direct. The mistakes of humanity are often attributed to people acting upon indirect evidence. Many wars have been started on the basis of indirect evidence.
An electron microscope produces an image (of a large molecule perhaps) that we can actually see. That's what counts. That's the point. That's the verification of the electron's existence, plus a thousand other processes that depend upon our current understanding of the existence of the electron.
It may well be the case in a hundred years' time that what we now understand about the force we've called an electron is found to be inaccurate. That's progress.
4. | It could still be wrong. That is in no way a basis for measuring the correctness of a scientific theory. Practicality in science isn't the same as practicality on the streets. |
Here, Dave is expressing his confusion most succinctly. The only way of measuring the correctness of any scientific theory is by providing a practical application based upon the theory. Any theory is only as correct, no more and no less, than the success of the products, applications, effects and consequences based upon the theory.
In the absence of a practical application, and that application includes any observable effect in a laboratory which may or may not have an immediate industrial or research utility, any theory is merely hypothesis or conjecture.
5. | So demonstrate that Dark Matter cannot be measured or detected. Show all the scientists who've measured and detected Dark Matter to be wrong. |
Here Dave is engaging in logical absurdity as well as misinformation to make a point. He's stating that Dark Matter actually has already been detected and that I must therefore be some sort of denialist. He's also adopting the fallacious argument used by religious adherents, ie. "if you're an atheist, prove to me that God does not exist".
We should all know by now that no-one can prove there is not green cheese on an unknown planet in an unknown solar system somewhere in the universe. But we may speculate that it is highly unlikely.
Let me quote Tim Thompson here, with whom I certainly agree on many points:
| We now know that if the dark matter we seek by astronomical observation were in fact made of ordinary baryonic matter, we would have seen it. We also know that we have not seen it. |
I will add, we have also not yet seen non-baryonic matter that would be a candidate for that 95% of the mass and energy of the universe, although there may be some unconfirmed and dubious reports of the occasional particle having been detected which some scientists, in their eagerness to achieve fame, claim may be the invisible matter in question.
6. | No, it seems that you think that indirect evidence isn't evidence at all, and you don't have a clue as to what an inference is. One cannot make predictions about the behavior of the universe based on "god" or "intelligent design." One can make predictions of what will be found if Dark Matter theory is correct. Several of those predictions have been verified, providing positive evidence for Dark Matter's existence, even if we have no direct evidence of its composition (although we do have direct evidence for several things it cannot be). |
Here's an excellent example from Dave of logical confusion. He accuses me of thinking that indirect evidence isn't evidence at all. Again he's trying to win an argument by 'dumbing down' his opponent. If anyone were to think that 'indirect evidence' is no evidence at all, then why would he think that a person would use the word evidence in the first place?
I'm a straight-talking person. If I think there's no evidence at all, I say so. Indirect evidence is unconfirmed evidence, hearsay, conjecture, inference, deduction. It can be important in providing leads, but that's all. Without repeated verification, which results in direct evidence, the indirect evidence remains a hypothesis or conjecture.
What's the problem Dave? You seem to have great difficulty in grasping this point.
7. | Asserting something doesn't make it true. You need to support your case regarding Dark Matter with actual evidence and argument. You've done neither to date. |
Again, an extension of the confusion. As in point (4), if one's objection is the lack of evidence in the first instance, one cannot provide evidence for the lack of evidence. Evidence either exists or it doesn't. Evidence for lack of evidence is an oxymoron.
8. | This is a reversal of reality. The proposition of Dark Matter was a change to existing theories. |
Dave, Dave, Dave, how could you get things so wrong? The proposition of Dark Matter is not a change to existing theories, it's a proposition which preserves existing theories.
Still friends?
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Dave W.
Info Junkie
USA
26022 Posts |
Posted - 11/04/2011 : 08:20:39 [Permalink]
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Originally posted by Sebastian
Dave W in his recent posts has provided a wealth of fallacious material we can all learn from. Thanks Dave for the examples. Let's examine them. |
The arrogance and condescension expressed above are incredible, considering how wrong you are.1. | Sebastian, you are pontificating about a subject you clearly do not understand. |
This is a typical defense used by someone who doesn't himself understand. Rather than help the poor person whom he claims doesn't understand, by providing useful and reliable information to clarify the matter, the attacker attempts to shield himself from his own ignorance by projecting his ignorance upon the other. |
Note that to make this accusation, you were forced to ignore the "useful and reliable information" that I provided to try to not only "clarify the matter," but to help you break free of your scientific ignorance.| One comes across similar responses frequently on internet forums. They tend to take the general form of ad hominem attacks, such as, "You're an idiot. You haven't a clue. What would you know? 10,000 experts can't be wrong. You're a denialist in the same category as those who denied the holocaust, etc etc." |
When it can be demonstrated that you are ignorant of a subject on which you choose to opine, it may still be an ad hominem attack, but at least you knew enough to avoid calling it a fallacy. An ad hominem attack certainly isn't fallacious when it is your behavior that is of interest here.2. | All the evidence we have for electrons is indirect, yet atomic theory has been verified over and over again. |
Dave really has a problem here. He seems to think that because one cannot hold an electron in the palm of one's hand and actually see it using one's eye balls, it's existence is in doubt. |
No, that's what you think about Dark Matter. If you, Sebastian, were to apply your standards of evidence consistently, you would be forced to conclude that atomic theory is "over the top" and not credible. Ironically, you are consistent in missing this point.| When Dave takes a photo with his digital camera, perhaps he's equally doubtful that photons exist. Perhaps he thinks that digital images appear through magic. Perhaps he thinks that the flow of electricity has nothing to do with electrons and that we just built power stations and tranformers through a process of trial and error which just happened to result in electricity. |
Now you've built another straw man that you are vigorously attacking, but it's actually a mirror of your own failure. I am not the one doubting a practical scientific model on the basis of the evidence being indirect, you are. Your statement, above, strongly suggests that you think that indirect evidence is no better than claiming that magic happens or that theories based on indirect evidence arise only through trial and error. Nothing could be further from the truth.3. | No, it seems that you think that indirect evidence isn't evidence at all, and you don't have a clue as to what an inference is. |
Here we have an example of a complete misreading of what I've written so far, plus a repetition of the first point I made, ie."...you don't have a clue.."
It is surely obvious that indirect evidence is inconclusive until it becomes direct. |
Indirect evidence never "becomes" direct evidence. Evidence will fall into one vaguely defined category or the other, always. (As I already noted, there is no scientific definition of these terms. Perhaps you, Sebastian, would like to provide a functional definition of the two terms, so that we can all distinguish between them?)| The mistakes of humanity are often attributed to people acting upon indirect evidence. Many wars have been started on the basis of indirect evidence. |
This is a fallacy, arguing from bad consequences. The implication is that because "indirect evidence" has been responsible for bad stuff, an upstanding moral person should avoid it. But neither science nor logic is about morality, which also makes these statements of yours red herrings.| An electron microscope produces an image (of a large molecule perhaps) that we can actually see. That's what counts. That's the point. That's the verification of the electron's existence, plus a thousand other processes that depend upon our current understanding of the existence of the electron. |
No, it only verifies that our model of electrons is good enough to provide useful technologies.| It may well be the case in a hundred years' time that what we now understand about the force we've called an electron is found to be inaccurate. That's progress. |
It would be, if electrons were a force.4. | It could still be wrong. That is in no way a basis for measuring the correctness of a scientific theory. Practicality in science isn't the same as practicality on the streets. |
Here, Dave is expressing his confusion most succinctly. The only way of measuring the correctness of any scientific theory is by providing a practical application based upon the theory. Any theory is only as correct, no more and no less, than the success of the products, applications, effects and consequences based upon the theory. |
Indeed! You finally got this correct by including "effects and consequences" along with "products and applications." Leaving "effects and consequences" out (which you had done until now) would mean that no aspect of cosmological theories could be considered "correct." Successful predictions of mere observations are a hallmark of a good theory, and Dark Matter theory has such predictions and observations.| In the absence of a practical application, and that application includes any observable effect in a laboratory which may or may not have an immediate industrial or research utility, any theory is merely hypothesis or conjecture. |
Then you must agree that Dark Matter theory is not "merely hypothesis or conjecture," because it has practical application as you define it.5. | So demonstrate that Dark Matter cannot be measured or detected. Show all the scientists who've measured and detected Dark Matter to be wrong. |
Here Dave is engaging in logical absurdity as well as misinformation to make a point. He's stating that Dark Matter actually has already been detected and that I must therefore be some sort of denialist. |
No, you made a claim about measurement and detection and neglected to actually apply your claim to the subject at hand. You left us with nothing but an implication, and I invited you to apply your own standards to Dark Matter.| He's also adopting the fallacious argument used by religious adherents, ie. "if you're an atheist, prove to me that God does not exist". |
Nope. Your implication was that Dark Matter is neither measurable nor detectable, and I was challenging you to support your claim.We should all know by now that no-one can prove there is not green cheese on an unknown planet in an unknown solar system somewhere in the universe. But we may speculate that it is highly unlikely.
Let me quote Tim Thompson here, with whom I certainly agree on many points:| We now know that if the dark matter we seek by astronomical observation were in fact made of ordinary baryonic matter, we would have seen it. We also know that we have not seen it. |
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You quote Tim Thompson saying that we can scientifically prove a negative in order to claim that we cannot prove negatives? Did you really think you could pull that off without anyone noticing?| I will add, we have also not yet seen non-baryonic matter that would be a candidate for that 95% of the mass and energy of the universe... |
That's absolutely correct. But not knowing the composition of Dark Matter doesn't mean that it doesn't exist. There are two questions that you continually conflate: "Does Dark Matter exist?" and "What is Dark Matter?" You can't take the "we don't know" answer to the second question and act as though it is a proper answer to the first question. The existence of a thing is not predicated upon our knowledge of its composition.| ...although there may be some unconfirmed and dubious reports of the occasional particle having been detected which some scientists, in their eagerness to achieve fame, claim may be the invisible matter in question. |
Once again, you are attributing motivations to scientists which you have not demonstrated that they have. Your straw man may suffer a bitter defeat through this sort of emotive rhetoric, but reality is unaffected.6. | No, it seems that you think that indirect evidence isn't evidence at all, and you don't have a clue as to what an inference is. One cannot make predictions about the behavior of the universe based on "god" or "intelligent design." One can make predictions of what will be found if Dark Matter theory is correct. Several of those predictions have been verified, providing positive evidence for Dark Matter's existence, even if we have no direct evidence of its composition (although we do have direct evidence for several things it cannot be). |
Here's an excellent example from Dave of logical confusion. He accuses me of thinking that indirect evidence isn't evidence at all. |
Considering that "hypothesis or conjecture" are not forms of evidence, you have proven with your own words (below) that you think that indirect evidence is not evidence.| Again he's trying to win an argument by 'dumbing down' his opponent. |
Thus you demonstrate that you don't know what the idiom "dumbing down" means. It's not a type of attack. One "dumbs down" something to make it more understandable by others.| If anyone were to think that 'indirect evidence' is no evidence at all, then why would he think that a person would use the word evidence in the first place? |
Because you clearly don't understand what "indirect evidence" is at all. You think you understand, but your position on what it is is self-contradictory.| I'm a straight-talking person. |
An appeal to character is an ad hominem argument directed at yourself.| If I think there's no evidence at all, I say so. |
By saying that indirect evidence is "hypothesis or conjecture," you are indeed saying that indirect evidence isn't evidence at all.| Indirect evidence is unconfirmed evidence, hearsay, conjecture, inference, deduction. |
No, indirect evidence is none of those things. Indirect evidence for a theory is evidence that depends upon some other theory also being true. Which is why just about every bit of evidence we have for every theory we have is indirect, which in turn is why a term like "indirect evidence" is not rigorously defined within the scientific establishment (because it is redundant).| It can be important in providing leads, but that's all. |
No, it depends upon context.| Without repeated verification, which results in direct evidence, the indirect evidence remains a hypothesis or conjecture. |
No, indirect evidence never graduates into becoming direct evidence. The idea that repeatedly examining indirect evidence can somehow make it become direct evidence is laughable in principle.Your knowledge of science is woefully deficient for you to be making pronouncements about the status of scientific theories. That's what the problem is.| You seem to have great difficulty in grasping this point. |
You are projecting your own failure onto me, here.7. | Asserting something doesn't make it true. You need to support your case regarding Dark Matter with actual evidence and argument. You've done neither to date. |
Again, an extension of the confusion. As in point (4), if one's objection is the lack of evidence in the first instance, one cannot provide evidence for the lack of evidence. |
Really? One cannot, for example, provide an empty result set from a search of the scientific literature as positive evidence that there is no evidence in favor of some theory or other?| Evidence either exists or it doesn't. |
Correct!| Evidence for lack of evidence is an oxymoron. |
Only if you mangle the English language to the point that "evidence for a lack of evidence for theory X" means the same thing as "lack of evidence for theory X." But they don't mean the same thing at all. Your claim can be supported, but you're just refusing to do the work to do so and trying to cover-up your refusal with weak semantic gambits.8. | This is a reversal of reality. The proposition of Dark Matter was a change to existing theories. |
Dave, Dave, Dave, how could you get things so wrong? The proposition of Dark Matter is not a change to existing theories, it's a proposition which preserves existing theories. |
If that is true, then you should be able to demonstrate that our cosmological theories included Dark Matter and Dark Energy prior to 1934. |
- Dave W. (Private Msg, EMail)
Evidently, I rock!
Why not question something for a change?
Visit Dave's Psoriasis Info, too. |
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Cuneiformist
The Imperfectionist
USA
4955 Posts |
Posted - 11/04/2011 : 22:08:35 [Permalink]
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Just to add to this discussion of dark matter, I was reminded of a press release from some years ago that shows more evidence for it.
I think there are some publications in peer-reviewed journals that I'll be able to access when I'm on campus tomorrow that add more to this story. Point is, people are actually testing these ideas in new ways and the data do seem to point in a positive direction. |
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Dave W.
Info Junkie
USA
26022 Posts |
Posted - 11/04/2011 : 23:07:12 [Permalink]
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Originally posted by Cuneiformist
Just to add to this discussion of dark matter, I was reminded of a press release from some years ago that shows more evidence for it. |
Yeah, the Bullet Cluster is an awesome example of the phenomena we actually see that are explained better by Dark Matter than any competing cosmological theory. Ethan Siegal offers a nice summary of the process, looking at three different galactic collisions and their different configurations of mass and matter.| I think there are some publications in peer-reviewed journals that I'll be able to access when I'm on campus tomorrow that add more to this story. Point is, people are actually testing these ideas in new ways and the data do seem to point in a positive direction. |
Yeah, but you'll notice that Sebastian hasn't addressed any of the evidence presented in this thread (or elsewhere). How could he? He dismisses indirect evidence by labeling it as things that are clearly not evidence at all, so if he were to attempt to criticize it as evidence his arguments would necessarily be incoherent. He refuses to acknowledge that the author of one of his own references states in no uncertain terms that Dark Matter is a better solution to the cosmological puzzles we face than the author's own idea. He thinks that his fabricated motivations for scientists are more profoundly troubling to the enterprise of cosmology than any of the data.
He doesn't even know enough about the words he uses to understand that "hearsay" is a legal term, and not a scientific one. It's like he's trying to be scientific using nothing more than a thesaurus, a press release and his own Dunning-Kruger-addled mind. |
- Dave W. (Private Msg, EMail)
Evidently, I rock!
Why not question something for a change?
Visit Dave's Psoriasis Info, too. |
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Tim Thompson
New Member
USA
36 Posts |
Posted - 11/05/2011 : 12:26:51 [Permalink]
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Tomorrow (yep, Sunday) I go to Los Angeles Valley College to give a talk on dark matter & dark energy.
Originally posted by Sebastian
What is already known (by anyone, expert or layperson) is often simply wrong or at best inaccurate. { ... } Because my general understanding from readings in the history of science is that our theories of gravity have always been problematical. Correct me if I'm wrong. { ... } To my mind, to put it simply and perhaps crudely, it's as though a group of scientists is saying, "Heck! We don't even know what gravity is, so let's support our inadequate theories of gravity, when we have a serious problem a billion light years away, by inventing a much more elusive force called Dark Energy."
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I see this collection of comments as indicative of naive thinking favoring ignorance over knowledge. The first sentence may not be factually incorrect, but is seriously misleading. The second sentence is likely to be factually incorrect, depending on how one chooses to define or interpret the word 'problematical". The last sentence is certainly just plain wrong.
The key to understanding what is really going on is seen in a clash of comments that brings out a fundamental philosophical difference.
Originally posted by Tim Thompson
Inference from observation is a crucial element of the scientific process and should not be discounted as "merely hypothetical". Not all hypotheses are created equal nor should they all be considered on equal footing. In this case, the hypotheses of dark matter & dark energy are both supported by significant observational data. If astrophysical dark matter is baryonic, then where & what is it and how does one explain that it is not visible to instruments which have the capability to see it? That is just as serious an issue as the fact that non-baryonic dark matter has not been directly detected, and in my mind a more serious issue in fact, which gives significant weight to the dark matter hypothesis.
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Originally posted by Sebastian
The only way of measuring the correctness of any scientific theory is by providing a practical application based upon the theory. Any theory is only as correct, no more and no less, than the success of the products, applications, effects and consequences based upon the theory.
In the absence of a practical application, and that application includes any observable effect in a laboratory which may or may not have an immediate industrial or research utility, any theory is merely hypothesis or conjecture.
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Here is how I interpret Sebastian's comment: All theories are merely hypothesis or conjecture, unless the theory can produce a practical application in a controlled laboratory environment. This is a serious departure from any standard philosophy of science, where observations in an uncontrolled natural environment stand on equal footing with observations in a controlled laboratory environment (there are advantages & disadvantages to both).
Query for Sebastian: If my interpretation is incorrect, then please provide a complete & unambiguous statement of what you do think about the relationship between controlled laboratory experiments and observations in an uncontrolled natural environment.
Our past understanding of theories of gravity have been "problematical" only in the sense that those theories lead to the solution of old problems, but the introduction of new problems. I think that Sebastian's understanding of the history & philosophy of science is flawed. A more correct view of the history of theories of gravity goes like this:
Prior to Galileo it was assumed (because Aristotle said so) that heavy objects would fall faster then light objects. Galileo was the first to test the validity of this assumption with real physical observations (carried out by rolling balls down inclined planes since he had no means of accurately timing straight falls). So post Galileo they knew that all objects would fall with the same acceleration regardless of their weight. They did not know why objects fall that way, but they did know how objects fall, and in that Galileo was neither "problematical" nor "wrong". This finding of Galileo about gravity remains accepted as fact today.
Newton used the facts discovered by Galileo to produce the first theory of gravity, and in so doing was able to explain why thing's fall the way Galileo discovered that they do fall. The old problem was answered, and Newtonian gravity is certainly not considered to be "wrong" even today; we still commonly use it in all manner of theoretical & practical applications. Newton's theory of gravity certainly did answer the old question left behind by Galileo, "why do heavy objects fall with the same acceleration as light objects?" But Newton's theory of gravity also, not surprisingly, introduced a serious new question. Newton's theory of gravity requires changes in the force of gravity to be felt instantly over arbitrarily large distances. This is called "instantaneous action at a distance", and Newton himself thought that such a thing could not possibly be correct. So Newton did not fully accept his own theory, but there was no denying that his theory explained every observation available in his day. It worked. But is is critical here to understand that Newton and his contemporaries were well aware of the weakness of the idea of instantaneous action at a distance. They did not accept his theory as any kind of absolute truth, they simply used it because it worked.
The problem of instantaneous action at a distance was not settled until a few hundred years later, when Albert Einstein came up with the theory of general relativity (GR). A strict interpretation of GR reveals that gravity is not a "force" at all, but rather a purely geometric effect. The fact that gravity is simply geometry in GR immediately explains why objects of different mass fall with the same acceleration. However, one can also formulate GR so as to treat gravity as a field, and therefore a classical force, in the same way as Newtonian gravity can be seen as a field. In this case, the force of gravity propagates with the speed of light, not instantaneously, finally solving Newton's problems over instantaneous action at a distance. Of course, Einstein's GR answered the old questions (like the classical problem of the perihelion advance of Mercury), but also introduced myriad new questions, which physicists are working on even as we speak.
The point of all this is that Sebastian's third sentence above is dead wrong. At no time have astronomers ever thought or behaved as he implies (I have worked in the profession myself for decades and have never met anyone who thought that way). Astronomers, and indeed scientists in general, are always on the lookout for new theories and better answers, even when it appears that the answers in hand are good enough. It is precisely because of the constant questioning of the old theories that new theories come along when they do. These are not accidental events, but rather the result of constant and deliberate research.
As I read Sebastian's comments, one would think that one theory of gravity follows on another by some random process. But in fact each theory in succession is an improvement on those that have come previously. So if one assumes that there is some ideal perfect theory of gravity, then each new theory narrows in on the one true theory. There is a clear path towards "perfection", a clear path towards decreasing levels of "problematic" and "inaccurate".
As for dark energy in particular, Sebastian's notion makes no sense to me at all. It all goes back to the fundamental principle of inference from observation. The idea that dark energy is just some arbitrary invention to rescue an otherwise failed theory is quite wrong. It is in fact a direct inference from observation, not an inference from theory.
Originally posted by Sebastian
As I understand, but correct me if I'm wrong, there are currently serious problems using Einstein's theories and equations in describing the behaviour at the Event Horizon of Black Holes.
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There are no "serious problems" that I am aware of. There are of course things that are unknown or very difficult to understand, especially regarding the interiors of black holes. There is also the still vexing problem of reconciling general relativity with quantum mechanics (string theory being the leading candidate in my opinion). But I know of no instance where Einstein's equations should work but do not.
I do know that one can observationally distinguish black holes from all other known or proposed compact objects because only black holes lack a solid surface. Hence, falling stuff that impacts a hard surface flares differently from stuff falling through an event horizon. This observable behavior is consistent with assumptions based in implied mass for astronomical objects that may or may not be black holes (e.g., Paul, et al., 1998; Done & Gierlinski, 2003; Remillard, et al., 2006). Furthermore, GR tells us that black holes should cast a "shadow" as a result of gravitational lensing. We are closing in quickly on the technological ability to observe the shadow of the supermassive black hole at the center of the Milky Way (e.g., Huang, et al., 2007).
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The point of philosophy is to start with something so simple as not to seem worth stating, and to end with something so paradoxical that no one will believe it. -- Bertrand Russell |
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Skepticism about the Big Bang
